Loss of control

Investigation summary

What happened

On 28 March 2025, the Sky Aces formation aerobatics team, which consisted of 4 Pitts‑type aircraft operated by Paul Bennet Airshows, was performing a display at the Avalon Australian International Airshow, at Avalon Airport, Victoria. A Pitts S1-11X, registered VH‑PVX, was one of the 4 aircraft. 

During the aerobatic display, the pilot of VH-PVX entered a triple avalanche manoeuvre, which is a loop with 3 snap rolls at the top. The pilot completed the snap rolls, then attempted to complete the loop. The aircraft collided with the ground resulting in substantial damage to the aircraft and serious injuries to the pilot.

What the ATSB found

The ATSB found that the aircraft had a lower nose attitude during the snap rolls, which was likely a result of starting the first half of the loop 100 ft lower than the previous commencement height of 200 ft. While the snap rolls were commenced at approximately 800 ft, which was similar to comparison flights, the low nose attitude limited the aircraft’s ability to climb and resulted in the pilot finishing the snap rolls at about 200 ft lower. From the lower height, the pilot then completed the final part of the loop, with insufficient height to safely recover from.

The ATSB also identified several factors that increased the emergency response times to reach the pilot. Although it was unlikely that this additional time affected the consequences of the pilot’s injuries, these factors could, however, affect survivability in a similar circumstance.

What has been done as a result

The event organiser is in the process of redesigning the pyrotechnic area for future airshows to provide clearly identified routes of entry for emergency services to safely access the pyrotechnic field if necessary. This will involve updating transport and emergency management plans, as well as providing briefings to all emergency services agencies and onsite personnel. The organiser will also adopt similar requirements for aerobatic displays to those instituted by the United Kingdom Civil Aviation Authority, with exceptions provided on a case-by-case approval. These include minimum height requirements based on aircraft performance and pilots having ‘gate’ parameters or check altitudes set for all critical junctures of an aerobatic manoeuvre. Further, the organiser is proposing to stage an ambulance with the Aviation Rescue Fire Fighting Services to reduce accident response times.

Safety message

The accident highlights that, although the nature of low-level aerobatics is a high-risk activity, those who participate in these activities can reduce risk by using personal minimum safe heights. This may include:

• setting and adhering to minimum safe heights for the commencement of manoeuvres
• confirming the aircraft’s height before commencing a manoeuvre 
• confirming height prior to reaching a point of no return and having an exit strategy if the height is below the pilot’s minimum
• undertaking regular reviews of your own and other team members’ in-flight video recordings and engaging in regular debriefing of these, particularly checking that selected minimum commencement height are adequate.

Additionally, any risks identified that may impact the emergency response, should have appropriate controls put in place to ensure responders can act quickly and effectively.

The investigation

The occurrence

On the afternoon of 28 March 2025, the Sky Aces formation aerobatics team, which consisted of 4 Pitts‑type aircraft operated by Paul Bennet Airshows, were performing a display at the Avalon Australian International Airshow, at Avalon Airport, Victoria. The 4‑ship¹ formation included the Pitts S1‑11X aircraft registered VH‑PVX.

VH-PVX and another aircraft became airborne at about 1710 local time. At about 1715, the pilot of VH‑PVX departed the formation, to start a solo routine. During this solo routine, the pilot planned to complete an aerobatic manoeuvre known as a triple avalanche. The triple avalanche was a combination of a loop with 3 snap rolls² at the top (Figure 1). The snap rolls were entered and exited from an inverted position.

Figure 1: A successful triple avalanche manoeuvre performed by the pilot in VH‑PVX on 26 March 2025

This is a still image extracted from a video recording of the validation flight (see Validation flight). Source: AMDA, annotated by the ATSB

The pilot entered the first half of the loop from approximately 100 ft above ground level (AGL) (see Recorded information). At the top of the loop, while in an inverted position, the altimeter showed that the aircraft was approximately 800 ft. The pilot then initiated 3 snap rolls, during which the aircraft drifted toward the show line (see Air display information). The pilot finished the snap rolls inverted with the aircraft banked away from the show line. They then began the descending part of the loop, however, they had insufficient height to recover. At about 1717, the aircraft collided with terrain, resulting in substantial damage to the aircraft (Figure 2).

The aircraft came to rest upright, west of runway 18/36, within an area that had been designated for fireworks and other pyrotechnics. The pyrotechnic team members were first to arrive at the accident site. They reported a strong smell of fuel and extricated the pilot from the aircraft. The Aviation Rescue Fire Fighting Service (ARFFS)³ arrived a short time later. The pilot was airlifted to hospital and sustained serious injuries. They reported that they had no recollection of conducting the accident manoeuvre.

Figure 2: Aircraft wreckage

Source: ATSB

Context

Pilot information

The pilot held a Commercial Pilot Licence (Aeroplane) issued in 1999, and a current class 2 aviation medical certificate, which was suitable for the operation type. They completed a single-engine private instrument rating in August 2023, which fulfilled the requirements of a single-engine flight review. The pilot’s logbook showed they had approximately 2,248 hours of total flight experience. 

The pilot had a formation aerobatics flight activity rating issued in 2015 and was approved to conduct aerobatics without an altitude restriction. They held design feature endorsements including tailwheel and manual propeller pitch control, which were required to operate the aircraft. 

The pilot had competed in aerobatic championships and reported that they had flown with the lead pilot since approximately 2002. More recently they had flown as a part‑time member of the Sky Aces aerobatic team.

Operator information

The operator, Paul Bennet Airshows, was a specialist in aerobatic flying and vintage aircraft displays. They were commonly invited to take part in airshows across Australia and internationally. The Sky Aces formation team had performed at multiple airshows prior to performing at Avalon. In preparation for the Avalon airshow, the Sky Ace formation group practised their routine and completed the flight validation required by the event organiser (see Validation flight).

Aircraft information

General 

The Pitts S1-11X aircraft was a single-seat aerobatic, amateur-built biplane, modified from the Pitts S1-11B, and constructed in Germany in 2010 by Wulf (Wolf) Aircraft. It was powered by a Ly-Con AEIO-540-EXP experimental engine and fitted with a 3-bladed, MTV-6 constant-speed propeller of laminated wood construction. The wings were predominantly made of timber with a fabric covering. They were externally braced against each other and the fuselage using a series of flying wires, landing wires, interplane struts, cabane struts⁴ and incidence wires. The aircraft type did not have wing flaps fitted and all wings had ailerons. The landing gear consisted of left and right forward main gear and a small tailwheel at the rear. The aircraft was a combination of fabric‑covered wood and metal, as well as composite materials, and was designed for unlimited aerobatics up to +/-10 g.5

VH-PVX (Figure 3) was first registered in Australia in 2015 and issued with a special certificate of airworthiness in the experimental category.⁶ It had been operated by Paul Bennet Airshows since that time. 

Figure 3: VH-PVX at Avalon Airshow prior to the accident

Source: Aircountry

Maintenance

The aircraft was maintained as per Civil Aviation Safety Authority Schedule 5 of the Civil Aviation Regulations and required a periodic inspection every 100 hours or 12 months, whichever came first. The most recent periodic inspection was conducted by an authorised maintenance organisation on 28 February 2025. At the time of the accident, the aircraft had accumulated 303 hours total time in service, about 5 hours of which were since the previous periodic inspection. There were no defects listed on the aircraft maintenance release.⁷

Altimeter accuracy

In February 2025 the aircraft’s altimeter accuracy was checked during a periodic inspection and found to be within allowable limits. Additionally, about 3 minutes before the accident, the onboard camera showed the aircraft’s altimeter reading approximately 1,200 ft, which was consistent with the automatic dependent surveillance‑broadcast⁸ (ADS‑B) altitude of 1,214 ft above mean sea level recorded for another of the formation aircraft operating at a similar altitude as VH‑PVX. Flight data was not available for VH‑PVX on this flight.⁹

Canopy

VH-PVX was fitted with a side‑opening canopy. There were no instructions for opening the canopy visible on the outside of the aircraft (Figure 4 top image). This was contrary to the Civil Aviation Safety Authority Civil Aviation Order 101.28 Airworthiness certification requirements – Amateur-built category aeroplanes, section 3.27 Markings and placards that stated markings were required: 

…on both the outside and inside of each exit door, hatch or canopy, indicating the position of the opening handles with locks fully engaged and also providing essential operating instructions for opening.

An example of such instructions on another aircraft is shown in Figure 4 (bottom image). 

Figure 4: Outside of canopy on VH-PVX (top image) compared with a different aircraft showing opening instructions (bottom image)

Source: ATSB

The operator reported emergency services and pyrotechnicians were provided with extraction details prior to every airshow.

Meteorological information

The Bureau of Meteorology provided automated weather observations taken at 1-minute intervals at Avalon Airport during the aerobatic display. Between 1710 and 1717, the highest recorded windspeed was 5 kt with gusts up to 6 kt. The temperature was 30°C, visibility was greater than 10 km, and the atmospheric pressure ranged from 1015‍‍–‍1014 hPa for the period. 

Recorded information

Flight data was recovered from an onboard accelerometer unit fitted to the aircraft. The unit recorded elapsed time and acceleration g‑forces, but the data was inconsistent with the flight behaviour. Therefore, it was not used in the analysis. Various sources of video that captured the accident flight were available, so video analysis techniques were employed to generate flight path estimates of the aircraft during the accident manoeuvre.

The in-cockpit camera recording was found to be the most suitable source for the video analysis. It recorded a partial view of the instrument panel, the back of the pilot and view of the outside. Various features visible in the video with known locations were analysed using commercial camera tracking software¹⁰ to determine the path of the camera. Specifically, it produced information on the aircraft latitude, longitude and height above ground for each frame, which was used to create an estimated flight path.

The operator also provided the ATSB with 2 videos from the cockpit of VH-PVX that were recorded with the same pilot flying at a previous airshow. These videos were recorded on a GoPro camera in a similar, but not the same, position as the accident flight (over the pilot’s left shoulder). An analysis of these videos and the accident flight is discussed below. 

Aerobatic manoeuvre

Standard process

The pilot described the normal process they would use to complete the triple avalanche manoeuvre, which included the first half of a loop followed by 3 snap rolls and then the final part of the loop (Figure 1). They stated they would normally enter the loop pulling about 4–5 g, then gradually reduce the g toward the top of the loop to start the snap rolls with a slight nose up attitude. Through the process of completing the snap rolls, it was possible for the aircraft to laterally cross the intended show line (see Air display information). In this circumstance, the pilot reported they usually checked the ground position immediately following the completion of the snap rolls and made corrections if they were no longer aligned with the show line. The pilot indicated their personal minimum height for commencing the snap rolls was 1,000 ft AGL. 

Previous flights

In the 2 previous videos provided, the onboard altimeter showed that the pilot began the first half of the loop at 200 ft AGL, began the snap rolls at 800 ft, and finished the snap rolls at 1,200 ft in one instance and at 1,000 ft in the other. In both videos, the pilot completed the final half of the loop and recovered to straight and level flight above 200 ft.

Also, in the first video, the nose attitude of the aircraft appeared to be further above the horizon at the beginning of the snap rolls when compared with the second video. This resulted in more height gained during the snap rolls in the first video. Prior to commencing the snap rolls, the aircraft appeared to be in a nose up attitude. When the pilot commenced the snap rolls the aircraft continued along a similar trajectory in the direction the aircraft’s nose was pointing before the snap rolls were commenced. That is, when the aircraft nose was pointing above the horizon prior to the snap rolls, the aircraft continued in an upward direction while performing the snap rolls. 

Accident flight

Loop entry height

During the accident flight, the onboard altimeter was visible prior to commencing the snap rolls at 800 ft and just prior to the collision with terrain at 100 ft. However, it was not visible during the entry to the loop, or at the completion of the snap rolls.

Therefore, to establish the height the pilot entered the first half of the loop, the ATSB used a combination of the ATSB’s estimated flight path, the aircraft’s altimeter (when in view of the camera) and the height of the aircraft during other low-level passes throughout the display. Table 1 provides this information at various stages of the accident manoeuvre. Figure 5 is a simplified recreation of the path the aircraft flew on the accident flight and the comparison flights. 

Table 1: VH-PVX manoeuvre sequence

There were discrepancies between the estimated height and the onboard altimeter. Such as during the descent, at 0.4 seconds (Figure 5 D) before the collision with terrain, the altimeter showed 100 ft AGL. At that point, the ATSB estimated height was 47 ft. Although, it was possible that the altimeter was lagging the actual height of the aircraft for the short time it was visible due to the descent rate.

However, it was noted that the low-level passes performed during the display and when the altimeter was visible, the aircraft instrument indicated the pilot was flying at approximately 100 ft. Therefore, it was determined that the entry height to the first part of the loop was likely to be about 100 ft. This was 100 ft lower than seen in the comparison flights.

Figure 5: Comparison of the previous and accident flights, showing the nose attitude when reaching 800 ft when starting the first part of the loop at different heights

The reference points A, B, C, D refer to Table 1. Source: ATSB

Snap roll height gain

As seen in the previous flights, the aircraft gained approximately 200–400 ft during the snap rolls. This allowed the pilot to start the recovery (final part of the loop) from no lower than 1,000 ft. However, the estimated flight path showed that in the accident flight, this was not achieved.

While there was some margin of error due to the available data sources, the ATSB recreation of the flight path from the onboard video estimated that only around 14 ft of height was gained during the snap rolls.

Attitude comparison

The ATSB compared the aircraft’s nose attitude during the snap rolls in the accident flight with the comparison flights. As the exact position, orientation and settings of the cameras varied between the 3 videos, the ATSB was unable to make a quantitative assessment of the difference in attitude between each of the flights. However, a visual comparison of the videos indicated a noticeable difference in attitude between the accident and comparison flights (Figure 6, Figure 7). Additionally, when the pilot reviewed the onboard video recording of the accident flight with the ATSB, they identified that the nose was low on the first snap roll. 

Figure 6 shows the accident flight nose attitude is closer to the horizon when starting the snap rolls than seen in the comparison flight. Figure 7 shows that the accident flight finishes the snap rolls with a lower nose attitude than the comparison flight. Although, it is harder to make a comparison in this image due to the bank angle on the accident flight.

Figure 6: Aircraft’s nose attitude when starting the snap rolls for the accident flight (top image) and a comparison flight (bottom image)

Source: Operator, annotated by the ATSB

Figure 7: Aircraft's nose attitude when finishing the snap rolls for the accident flight (top image) and a comparison flight (bottom image)

Source: Operator, annotated by the ATSB

Final loop segment and recovery

To recover from the triple avalanche, the pilot needed to have sufficient height after the snap rolls to complete the final part of the loop without entering an aerodynamic stall or colliding with terrain. The comparison flights showed this height increase could be achieved during the snap rolls.

Summary of comparison flights 

Table 2 provides a summary of the comparisons made across the 3 videos supplied by the operator.

Table 2: Summary of comparison data

Wreckage and impact information 

The aircraft collided with terrain on a grassed area west of runway 18/36, in a location of the airport designated as the pyrotechnic box (seeAir display information). In this area, there were multiple pyrotechnics ready to be used in the Sky Aces show, along with many boxes of fuel that were planned to be ignited during the ‘wall of fire’ display later that evening.

A ground scar, approximately 95 m long, was on a south-south-west heading (Figure 8). The aircraft tumbled around the nose and came to rest upright and oriented toward north, almost opposite the direction of the impact sequence and debris trail. The initial impact point occurred about 10 m from the fuel boxes within the pyrotechnics (Figure 8).

Figure 8: Overview of pyrotechnics and point of VH-PVX collision with terrain

Source: Royal Australian Air Force No 1 Security Forces Squadron, annotated by the ATSB

An image taken from the onboard camera showed that the aircraft was in close proximity to the pyrotechnics before (Figure 9) and at the point of the collision with terrain. 

Figure 9: VH-PVX just prior to collision with terrain showing proximity to pyrotechnics

Source: ATSB

The ATSB conducted a preliminary examination of the aircraft at the accident site, but due to access restrictions for the operational airport and airshow, the wreckage was then relocated to a secure facility for detailed examination. Examination of the wreckage identified:

• There was no evidence of any defects or failures that may have been present before the impact, and which could have contributed to the development of the accident.
• The uppermost section of the canopy windshield was fractured partly from the accident sequence and then from first responders accessing the cockpit.
• The engine mounts had fractured, with the engine remaining tethered by the main fuel line, engine controls and wiring loom. 
• The propeller hub remained attached to the engine and fragmentation of the propeller blades was indicative of the engine providing power at the time of the collision.
• The forward main landing gear had permanently splayed outward, the tailwheel strut exhibited some upward deflection, the engine sump cover had fractured, and the lower fuselage section had sustained compression damage, consistent with a hard landing in an upright orientation.
• The upper wings had separated from the aircraft, with the wing spars fracturing outboard of the cabane strut attachment. The lower wings sustained impact damage but remained secured to the fuselage.
• The rigid lines between the fuel tanks and selector valve were fractured, resulting in post-accident leakage of fuel. However, the fuel tanks remained intact and there was no post-impact fire.

Air display information

General

Held every 2 years over 6 days, the Avalon Australian International Airshow combined Australia’s largest aviation, aerospace and defence industry trade exposition with a 3-day airshow. The event was organised by the AMDA Foundation (AMDA), which was the chosen name to reflect the consolidation of Aerospace Australia Limited and Industry Defence and Security Australia Limited.

AMDA provided a briefing on airshow operations and safety to all airshow pilots prior to the airshow. This included the expected timetable of display events, pilot responsibilities, display area information, manoeuvre limitations, minimum heights, minimum weather conditions and holding areas. It also included a brief of the emergency procedures and airshow terminology that would be used to terminate displays in the event of an emergency.

Event operations centre

AMDA had created an emergency response plan, which stated:

The priority of the EOC [event operations centre] Manager and Chief Warden in an emergency is to support the emergency control agency and provide clear communication to the Area Wardens within each event zone.

The emergency response plan defined a potential or declared emergency as:

An emergency is when there is a potential incident or incident that could be beyond the ability of the normal day to day management structure. An emergency is described as any incident that:

• Has the potential to cause or is causing loss of life and extensive damage to property, infrastructure or the environment.

• Has the potential to have or is having a significant adverse consequence for the Airshow event, guests, staff and aircrews.

• Requires the involvement of two or more emergency control agencies to respond to a class of emergency as defined in the Emergency Management Act 2013.

     - Class 1 Emergency

     - Class 2 Emergency

It further stated the roles and responsibilities of the event operations centre as follows:

The EOC Manager is required to monitor activity across the precinct and deploy additional resources to assist or deal with incidents as they are reported or identified through CCTV or the AMDA Call Centre.

These include managing critical security, medical or safety incidents which may require a higher level of resources, real time monitoring or a significant management focus. These incidents can occur multiple areas and require deployment of specialised or centrally managed resources.

The EOC Manager is responsible for delegating roles and responsibilities within the EOC to ensure appropriate resources are managing each incident and can escalate to Victoria Police as required.

Designated areas

Designated areas were mapped on Avalon Airport to assist in segregating the airshow from spectators. The airshow had several displays that used pyrotechnics, including the Sky Aces routine. The pyrotechnics detonation area was located to the west of runway 18/36 inside the flight display area. Show lines were created to assist aircraft with conducting displays at an appropriate distance from the crowd (150 m, 250 m, 350 m and 500 m). The show line to which a display could be performed to, was determined by the aircraft’s speed during the display. Cameras were placed on each show line and monitored to ensure aircraft were conducting their displays at a safe distance from the spectators (Figure 10).

Figure 10: Avalon Airport designated areas

Source: AMDA, annotated by the ATSB

The display pilot briefing provided by AMDA stated that aircraft with a maximum display speed between 101 kt and 200 kt could conduct their display as close to the crowd as the 150 m show line. At the time of the accident manoeuvre, the pilot was performing at about 160 kt and performing close to the 150 m show line.

During the snap rolls, the aircraft moved towards the 150 m show line. When the pilot reviewed the accident video, they believed they attempted to correct this, which was also evident from the show line video (Figure 11).

Figure 11: VH-PVX reference to 150 m show line, shows the aircraft moving towards the show line, then away from the line

The image is made from several images overlaid on each other to show the sequence of VH-PVX. The VH-PVX label shows the first position of the aircraft in the manoeuvre sequence. Source: AMDA, annotated by the ATSB

Validation flight 

AMDA required that participants in the airshow successfully complete a validation flight prior to the public display. On 26 March 2025, the Sky Aces formation team satisfied this requirement, which involved the pilot completing their solo display including the accident manoeuvre in VH-PVX. The validation report had not noted any concerns about the routine or ability of those involved to successfully perform it on the day of the show. There was no comparison video available as evidence of the heights the manoeuvre was performed at during the validation flight.

Event risk assessment

AMDA conducted a risk assessment for the airshow and identified multiple hazards.  Some of the associated risks identified that were relevant to the accident included:

• pyrotechnic display operator injured/killed by aircraft wreckage and/or flare debris impact into pyrotechnic area during airshow

• aircraft/vehicle malfunction or crash during atypical flying display

• vehicle or aircraft transits across the pyro [pyrotechnic] box bursting or igniting flammable liquid explosives

• blocking ARFF [Aviation Rescue Fire Fighting Services] route out of the fire station (Figure 12) with resultant impact on ARFF emergency response times. 

Risk controls were implemented by AMDA to reduce either the likelihood or consequences of the identified hazards, which included:

• pyrotechnics placed outside the runway strip
• minimising pyrotechnician personnel in the pyrotechnic area during the airshow
• a briefing provided to airshow pilots
• having emergency services in attendance including ARFFS
• AMDA’s emergency response plan
• pilots flying in displays were experienced and were required to complete a validation flight.

To ensure taxiway Foxtrot (Figure 12) remained clear for ARFFS units leaving the southern fire station in an emergency, aircraft movements to/from the southern tarmac were controlled by Airservices Australia air traffic control.

Figure 12: Avalon Airport taxiway and ARFFS southern location 

Source: Airservices Australia and Google Earth, annotated by the ATSB

Furthermore, Ambulance Victoria (AV) was contracted to attend the airshow to perform the following roles:

• to manage the pre-hospital impacts of the event through on-site AV resources and transport capability (if required)

• to mitigate the impact of the event on AV’s service delivery to the surrounding community; and

• to ensure that if an incident occurs at the event which evolves into a major emergency, there is an AV presence on-site to manage the pre-hospital response and emergency medical treatment as required, rapidly and effectively.

Survival aspects

Emergency response

An emergency response was activated at 1717 following the accident. Table 3 shows the sequence of events of the emergency response.

At 1718, the pyrotechnicians were first to arrive onsite. The pyrotechnicians were trained in first aid and were able to extricate the pilot from the aircraft, which they determined was necessary due to the strong smell of fuel and their assessment of a possible subsequent fire.

The pyrotechnicians reported having difficulties in opening the aircraft’s canopy, as the opening mechanism was not obvious from the outside. The onboard video showed that the pyrotechnicians took approximately 50 seconds to forcefully remove the canopy, which appeared to have already been damaged in the accident sequence.

At the same time, the ‘crash alarm’ was activated by the air traffic controller and the ARFFS dispatched 2 tenders¹¹ from the southern fire station and one tender from a temporary northern dispatch area. The northern ARFFS response tender crew reported they were unable to use taxiway Bravo while trying to access the accident site as a departing air transport flight was obstructing the taxiway. Instead, the crew opted to use the airport perimeter track and reached the accident site at approximately the same time as the ARFFS tenders responding from the southern side. The ARFFS reported increased response times due to the accident occurring inside the pyrotechnics area and navigating the associated hazards to ensure the safety of the responders. 

When the accident occurred, AV ambulances were already on location at the airshow. However, AV reported that their response time was impacted due to the need to wait for an escort to the scene as the airport remained active to assist with landing of the other formation aircraft. Avalon Airport and AMDA reported the delay was due to the escort waiting for the ambulance to make safe access. The ATSB could not verify the difference in these accounts, but the first ambulance arrived onsite at 1731.

Table 3: Emergency response sequence

Pilot injuries

The pilot sustained serious head, chest, abdominal, spinal and leg injuries requiring hospitalisation and long-term rehabilitation. The pilot was wearing a 5-point restraint and a cloth flying cap. 

ATSB analysis based on estimates of aircraft speed, impact angle, attitude, and energy absorption, indicated that the vertical acceleration experienced by the pilot would normally result in serious injuries, in addition to moderate to serious injuries from the horizontal component. 

The tail wheel was the initial impact point followed by the main landing gear, underside of the fuselage, fuel control unit and propeller. During that initial impact, the pilot’s seat crushed 5–8 cm into the fuselage, as the main landing gear spread, distorting the lower fuselage and fracturing the airframe. The pilot’s spinal injuries were almost certainly the result of the vertical impact forces. The gascolator (fuel strainer), located directly beneath the pilot’s seat, pierced the seat base and cushion, but its contribution to the pilot’s injuries could not be determined. 

The pilot’s left leg injury was consistent with crushing of the footwell during the impact sequence. 

After the initial impact, the aircraft tumbled around the nose (Figure 13), destroying the wings and propeller. The pilot was effectively retained in their seat by the 5-point restraint, minimising flail injuries, and the space around the pilot in the cockpit was retained. However, the canopy fractured and was associated with a superficial scalp injury. Had the pilot been wearing a hard-shell helmet, that injury would probably have been avoided, but it would unlikely have reduced the severity of other injuries. 

Figure 13: VH-PVX during the accident sequence

Source: David Caird, Herald Sun

Safety analysis

Introduction

The pilot of VH-PVX was conducting low level aerobatics at the Avalon International Airshow when it collided with terrain, resulting in serious injuries to the pilot and substantial damage to the aircraft. 

This analysis will examine the accident flight manoeuvre compared with previous flights. Additionally, the ATSB also reviewed elements of the emergency response, which, although not contributing to the accident, could have resulted in increased severity of injuries in a similar occurrence.

Lower manoeuvre height

The accident pilot had previously completed the triple avalanche manoeuvre (the accident manoeuvre) in VH-PVX. Video evidence showed on at least 2 previous occasions the pilot began the manoeuvre at 200 ft above ground level (AGL), started the snap rolls at approximately 800 ft, gained height during the snap rolls and recovered the aircraft. Conversely, the combined analysis of the accident video and flight path estimated by the ATSB showed that the pilot likely began the manoeuvre at approximately 100 ft, started the snap rolls at about 800 ft, but did not gain height throughout the rolls. Although the pilot stated their minimum was 1,000 ft for starting the snap rolls, all 3 flights showed the manoeuvre starting at 800 ft.

A comparison across the 3 flights indicated that, throughout the snap rolls, the nose attitude was comparatively lower or flatter during the accident flight. This was supported by the pilot’s observations when watching the accident flight onboard video. The lower nose attitude was likely a result of starting the first half of the loop 100 ft lower than the previous commencement height of 200 ft. That is, the extra 100 ft available to the pilot in the first half of the loop meant that the aircraft would have been further through the loop by the time they had reached 800 ft and was therefore in a flatter trajectory. As a result, an estimated 14 ft of height was gained during the snap rolls rather than 200–400 ft as achieved for the previous flights with a higher nose attitude.

As the pilot was unable to recall the events of the accident, it was unclear if they were aware of the reduced height when entering the final part of the loop. However, the onboard video and subsequent collision with terrain showed that the pilot elected to continue the manoeuvre although the aircraft did not gain height during the snap rolls. Consequently, there was insufficient height remaining to complete the manoeuvre before colliding with terrain.

Emergency response

Given the location of the flight display area, it was likely that any accident involving a display aircraft operating to the 150 m, 250 m, or 350 m show lines would occur inside the pyrotechnics area. Therefore, due to the increased risk associated with the pyrotechnics, the emergency crew response times were increased as they navigated the dangerous area while operating on an active airport. 

For example, the Aviation Rescue Fire Fighting Service had to assess the hazards associated with the pyrotechnics to ensure the safety of their personnel and one tender had to use an alternative route to the accident site due to a departing aircraft. Likewise, although ambulances were already in attendance at the airshow, it took approximately 14 minutes for them to arrive at the accident site. Ambulance Victoria reported increased response times due to requiring escorts to reach the accident site, however, it was not clear how long ambulances were stationary waiting for an escort.

In addition, the aircraft did not have instructions on how to unlatch the cockpit canopy from the outside, as required for airworthiness certification. However, first responders managed to pull the canopy open in approximately 50 seconds after they arrived onsite. Instructions for opening the canopy may have reduced this time.

Some of these factors could have reduced the time taken to provide assistance to the pilot. However, on this occasion, the pyrotechnicians extracted the pilot from the cockpit, preventing injuries resulting from a possible fire and ARFFS attended to the pilot within 4 minutes of the accident. Therefore, it was unlikely that the severity of the pilot’s injuries were increased due to the location of the accident.

Findings

From the evidence available, the following findings are made with respect to the collision with terrain involving Wolf Pitts S1-11X, VH-PVX, Avalon Airport, Victoria, on 28 March 2025.

Contributing factors

• The triple avalanche manoeuvre was likely initiated at a lower height than on previous occasions resulting in a lower nose attitude when commencing the snap rolls at 800 ft, which was also lower than the pilot’s designated height. As result, the aircraft did not gain sufficient height during the snap rolls to recover from the loop before colliding with terrain.

Other findings

• While not likely contributing to the severity of the pilot’s injuries, several factors increased the time taken to respond to the accident, including:

- the co‑location of the flight display area with the pyrotechnic detonation area

- the Aviation Rescue Fire Fighting Service had to assess and then safely navigate the pyrotechnics area

- Ambulance Victoria had to wait for safe access to the accident site

- the aircraft did not have visible markings on the outside about how to open the canopy.

Safety actions

Safety action taken by AMDA (the event organiser)

The event organiser reported pyrotechnic area locations that would be fit-for-purpose would still likely result in future possible airshow accidents occurring in the pyrotechnic area. However, it was in the process of redesigning the pyrotechnic area for future airshows to provide clearly identified routes of entry for emergency services to safely access the pyrotechnic field if necessary. This would involve updating transport and emergency management plans, as well as providing briefings to all emergency services agencies and onsite personnel.

The event organiser will adopt similar requirements for aerobatic displays to those instituted by the United Kingdom Civil Aviation Authority with exceptions provided on a case-by-case approval. These include minimum height requirements based on aircraft performance. Additionally, pilots will also be required to have ‘gate’ parameters or check altitudes set for all critical junctures of an aerobatic manoeuvre, such as the apex of a loop and before committing to ‘pulling through the vertical’ to continue the manoeuvre.

Further, AMDA is proposing to stage an ambulance with the ARFFS to reduce response times for any similar future accidents.

Sources and submissions

Sources of information

The sources of information during the investigation included:

• the pilot of the accident aircraft
• the lead pilot of the formation
• the airshow event organiser
• the maintenance organisation for VH-PVX
• accident witnesses
• video footage of the accident flight and other photographs and videos taken on the day of the accident 
• Airservices Australia
• Avalon Airport
• Bureau of Meteorology
• Civil Aviation Safety Authority
• Ambulance Victoria.

References

Civil Aviation Safety Authority. (2004). Civil Aviation Orders 101.28 – Airworthiness certification requirements – Amateur-built category aeroplanes.  https://www.legislation.gov.au/F2005B00951/latest/text

Submissions

Under section 26 of the Transport Safety Investigation Act 2003, the ATSB may provide a draft report, on a confidential basis, to any person whom the ATSB considers appropriate. That section allows a person receiving a draft report to make submissions to the ATSB about the draft report. 

A draft of this report was provided to the following directly involved parties:

• the pilot of the accident aircraft
• the other pilots within the formation team
• the airshow event organiser
• Airservices Australia
• Ambulance Victoria
• Avalon Airport
• Civil Aviation Safety Authority
• the maintenance organisation. 

Submissions were received from:

• another pilot in the formation team
• airshow event organiser
• Ambulance Victoria
• Avalon Airport.

The submission were reviewed and, where considered appropriate, the text of the report was amended accordingly. 

Purpose of safety investigations The objective of a safety investigation is to enhance transport safety. This is done through:  identifying safety issues and facilitating safety action to address those issues providing information about occurrences and their associated safety factors to facilitate learning within the transport industry. It is not a function of the ATSB to apportion blame or provide a means for determining liability. At the same time, an investigation report must include factual material of sufficient weight to support the analysis and findings. At all times the ATSB endeavours to balance the use of material that could imply adverse comment with the need to properly explain what happened, and why, in a fair and unbiased manner. The ATSB does not investigate for the purpose of taking administrative, regulatory or criminal action. About ATSB reports ATSB investigation reports are organised with regard to international standards or instruments, as applicable, and with ATSB procedures and guidelines. Reports must include factual material of sufficient weight to support the analysis and findings. At all times the ATSB endeavours to balance the use of material that could imply adverse comment with the need to properly explain what happened, and why, in a fair and unbiased manner. An explanation of terminology used in ATSB investigation reports is available here. This includes terms such as occurrence, contributing factor, other factor that increased risk, and safety issue. Publishing information Released in accordance with section 25 of the Transport Safety Investigation Act 2003 Published by: Australian Transport Safety Bureau © Commonwealth of Australia 2026 Ownership of intellectual property rights in this publication Unless otherwise noted, copyright (and any other intellectual property rights, if any) in this report publication is owned by the Commonwealth of Australia. Creative Commons licence With the exception of the Commonwealth Coat of Arms, ATSB logo, and photos and graphics in which a third party holds copyright, this report is licensed under a Creative Commons Attribution 4.0 International licence. The CC BY 4.0 licence enables you to distribute, remix, adapt, and build upon our material in any medium or format, so long as attribution is given to the Australian Transport Safety Bureau.  Copyright in material obtained from other agencies, private individuals or organisations, belongs to those agencies, individuals or organisations. Where you wish to use their material, you will need to contact them directly.

1. ^    Ship: refers to multiple aircraft flying in formation together. The preceding number refers to the number of aircraft in the formation.
2. ^    Snap roll: an aerobatic manoeuvre, which results in the aircraft making one revolution about its longitudinal axis with the aircraft aerodynamically stalled. An aerodynamic stall occurs when airflow separates from the wing’s upper surface and becomes turbulent. A stall occurs at high angles of attack, typically 16˚ to 18˚, and results in reduced lift.
3. ^    ARFFS: Aviation Rescue Fire Fighting Service provides rescue and firefighting services at select airports within Australia.
4. ^    The cabane struts connect the upper wings connection to the fuselage and form part of the overall bracing scheme.
5. ^    ‘g’ is an abbreviation for the acceleration due to the earth’s gravity. A positive acceleration equal to 10 times the earth’s gravity is described as +10 g.
6. ^    Experimental category: the Civil Aviation Safety Authority can issue experimental certificates to allow specific operations of aircraft, which are not by their nature type certificated or have modifications incorporated that are not yet approved.
7. ^    Maintenance release: an official document, issued by an authorised person as described in Regulations, which is required to be carried on an aircraft as an ongoing record of its time in service and airworthiness status. Subject to conditions, a maintenance release is valid for a set period, nominally 100 hours time in service or 12 months from issue.
8. ^    Automatic dependent surveillance‑broadcast equipment transmits real-time operational data from an aircraft’s global positioning system and pressure-sensitive altimeter, which enables air traffic service providers to track aircraft. Airservices Australia recorded the transmissions received by its network of ADS-B receivers. That data could also be received by privately-operated equipment used to feed information to flight tracking websites.
9. ^    It is common practice during formation flying for only one aircraft to broadcast its position.
10. ^   SynthEyes is a program for 3D camera tracking, also known as match-moving.
11. ^   Airport tenders are specialised fire engines that carry large amounts of water, foam and other rescue equipment.

Investigation summary

What happened

On 26 February 2025, a Robinson Helicopter Company R22, with an instructor and a student on board, departed Archerfield Airport, Queensland, to conduct advanced emergency training at Pannikin Island in Moreton Bay, Queensland. 

After practising emergency procedures and low-level flying, the student pilot performed several low-level torque turns, a manoeuvre not originally included in the lesson plan. During the final turn, the helicopter entered a low nose attitude and descended rapidly. The instructor attempted to recover, but due to the low height, was unsuccessful. The helicopter impacted the ground and skidded for some distance before rolling and coming to rest on its left side. The instructor sustained serious injuries and the student sustained minor injuries. The helicopter was destroyed.

What the ATSB found

Low‑level torque turns that were not part of the lesson plan, nor a requirement for commercial licence training, were conducted by a student pilot without a formal pre-flight briefing or guidelines. As the manoeuvre fell outside of the syllabus the ad hoc nature of its inclusion and conduct at the end of the lesson relied on an inflight briefing by the instructor to prepare the student for the exercise. Beginning the low-level torque turn exercise at 50 ft AGL rather than starting higher and working down as the student’s capability improved increased operational risk. Due to the low-level conduct of the exercise, this reduced the available safety margin and placed reliance on the instructor as the only risk control to recover from any unexpected mishandling of the sequence. 

Although the instructor immediately identified that the helicopter was descending rapidly, and took the controls, their actions were unable to recover the helicopter before colliding with terrain. Environmental conditions may have further reduced the safety margin and complicated the low-level recovery.

The operator had no formal process for monitoring the return of training flights. This would likely delay any search and rescue response and reduce post-impact survivability of the helicopter occupants in the event of life-threatening injuries.

What has been done as a result

The operator reported that SARTIME procedures for the flying school have been revised.

Safety message

Ensuring and maintaining sufficient height for recovery is vital in a training environment when a student has limited experience to manage unexpected aircraft or helicopter behaviour. 

All aspects of the lesson should be clearly briefed before flight including planned sequence, risks and hazards to ensure an understanding between instructor and student.

Instructors must rely on conservative in-flight decision‑making to manage risk during flight training operations and to anticipate and be ready to intervene quickly, especially during low-level, or elevated risk manoeuvres.

The investigation

The occurrence

On 26 February 2025, an instructor and a pilot under instruction (student) were conducting an advanced emergency training exercise in a Robinson Helicopter Company R22 (R22), registered VH-8BW, operated by Utility Helicopters, leased from Heliflite. The training commenced from the operator’s company base at Archerfield Airport, Queensland.

At about 0700, the student conducted a daily inspection of the helicopter under the supervision of the instructor. The intended training flight formed part of the requirements for a commercial helicopter pilot licence and the lesson plan intended to cover advanced emergency procedures. 

At about 0730 the helicopter, with the student flying, departed Archerfield Airport to the south‑east for a designated training area located in Moreton Bay. After reaching the uninhabited Pannikin Island training area, the emergency training commenced with autorotation[1] and tail rotor failure practise. After about 45 minutes, the student then commenced low-level flying practise, completing several clockwise laps around the island. These were completed between 50–100 ft above ground level (AGL) and at a speed of between 60–70 kt. 

Toward the end of the lesson, the instructor recalled that the student requested to practise some agricultural flying operations, which included torque turns.[2] These manoeuvres were not on the lesson plan for the flight, or part of the commercial flight training syllabus, and there had been no plan to conduct them until this point. The instructor demonstrated the manoeuvre before the student took control and successfully completed 4 torque turns. The instructor reported these were conducted at a height of about 50 ft AGL. 

The instructor stated that the low-level turns were conducted across the island roughly in an east–west direction. The exercise was conducted across the prevailing wind direction to avoid a downwind component on each low-level manoeuvre. Torque turns were performed on the eastern side of the island and procedural turns on the western side, with about 4 turns completed at each location. These were executed at a height of about 50 ft AGL. 

As the lesson neared completion, they elected to do one more torque turn before returning to base. The instructor recalled noticing the wind had increased a little and had started gusting but stated that these were not considered abnormal conditions and that both he and the student had flown in these conditions before.

The instructor described that at the top of the last torque turn, they were at a height of 100–150 ft AGL when they began to descend to build airspeed and return to level flight. During the recovery, the instructor noticed that the nose of the helicopter was pointing slightly down toward the ground at a height of about 20 ft. The instructor recalled that they were about to correct the student when a sudden gust of wind increased the rate of descent. Aware of the ground proximity,the instructor immediately took over the controls and recalled moving the cyclic[3] aft to arrest the rate of descent. The instructor reported the helicopter shuddering, shaking, and experiencing a jolt in the collective but was unable to prevent the helicopter impacting the ground. 

Both occupants recalled that everything happened quickly prior to ground contact and that the estimated speed at impact was about 60–70 kt. The instructor recalled that the helicopter impacted hard in a flared nose high attitude and that the stinger[4] contacted the ground first. The helicopter slid along the ground on its skids for about 40–50 m between mangrove bushes before the left skid dug into the muddy ground and dynamically rolled over.[5] The helicopter came to a stop on its left side after numerous rotations and was destroyed (Figure 1). The instructor recalled that the student remained in the helicopter momentarily after impact and then managed to exit and appeared to have had less injuries than themselves so was able to follow instructions to shut down the machine. 

Figure 1: Accident site

Source: Student

The student turned off the battery master and assisted the instructor to exit the helicopter. The instructor was unsure if any staff would be in the office and recalled asking the student to use their mobile phone to call for help. They stated that calling the office would not be as effective as calling their partner, as they were aware that several of the staff were away on business. The company was contacted and another helicopter from the base at Archerfield Airport was then dispatched to collect both occupants. About 25 minutes later they were rescued by a colleague who arrived in another helicopter. 

Emergency services were contacted, and an ambulance met the retrieval helicopter on arrival back at Archerfield Airport. Post-accident medical assessment determined that the instructor had sustained serious injuries and the student only minor injuries, both were taken to hospital for treatment.

Context

Aircraft information 

The Robinson R22 is a 2-seat, 2-bladed, single-engine, light utility helicopter manufactured by Robinson Helicopter Company in the United States. It has a maximum all up weight of 622 kg. The R22 is powered by a Lycoming O-360 4-cylinder piston engine that is derated to 131 horsepower for take-off and 124 horsepower for cruise at 2,652 RPM. The R22 is mostly used for private operations, rotary wing flight training and agricultural operations. 

The instructor reported that there were no mechanical issues identified with the helicopter during the daily inspection and pre-flight that would have precluded normal operation.

Flight controls 

The helicopter was fitted with conventional light helicopter flight controls, such as dual cyclic controls for each seat, and a centre‑mounted collective.[6] The engine throttle is connected to collective inputs through a mechanical linkage; when the collective is raised, the throttle is opened and when lowered, the throttle is closed.

Pilot information

Instructor 

The instructor held a commercial pilot licence (CPL-H) helicopter and had been an instructor with the operator for 3 years and 3 months. They began as a grade 3 instructor and progressed to a grade 1 instructor during their employment, logging about 2,800 flying hours. The instructor’s last proficiency check was 29 November 2024. The instructor obtained a low-level rating in 2021 and their low-level flight review for the R22 was valid until 13 November 2025. The instructor held a current Class 1 medical certificate.

Student pilot 

The student pilot had been conducting training with the operator for about 3.5 years. Initially training for a private pilot licence (PPL-H) helicopter, they had not finalised the required ground theory or conducted a flight test. Although they did not hold a PPL-H, they continued training to obtain the required flight hours for a CPL-H. 

Nearing completion of the commercial flight training, the student scheduled their lessons to coincide with their work commitments and they were not regular, but rather when time permitted. Their last lesson before the accident was conducted on 29 January 2025, about 4 weeks prior. They had previously completed advanced emergency training and the intention was to use the lesson as a refresher for CPL-H competency elements. The student reported they wanted to consolidate their low-level flying skills with a goal of working in the agricultural sector. 

At the time of the accident the student had accrued 89 hours of pilot training with the operator. The student reported that about two thirds of all the lessons had been taken with the instructor involved in the accident and the remainder with head of operations (HOO) and one other instructor. 

Meteorological information

Minute-by-minute wind data from the Bureau of Meteorology around the time of the accident indicated generally moderate winds with some directional variability.

Brisbane Airport observations recorded winds at 126°–143° with wind speeds of 9–13 kt, gusting to 18 kt. Similarly, Gold Coast Airport recorded winds at 150°– 208° with wind speeds of 9–14 kt, gusting to 18 kt. The accident site which was located between these two reporting stations (Figure 2) was likely subject to similar wind conditions.

Figure 2: Map showing location of weather stations and Pannikin Island

Source: Google Earth, annotated by the ATSB

The instructor stated that they checked the weather conditions before departing, and that the wind direction indicated a south‑easterly wind at about 15 kt. On arrival at Pannikin Island, they recalled that the surface wind was observed to be more southerly in direction and felt slightly stronger than 15 kt. 

Downdraught 

Downdraught is a vertical atmospheric condition where a current of air sinks rapidly, leading to sudden changes in conditions at ground level and can produce strong surface winds. Downdraughts can pose a significant threat to rotary aircraft, particularly while manuevering at low level. The most common causes of downdraught experienced by helicopter pilots are due to irregular terrain when combined with strong surface winds, mechanical turbulence,[7] temperature inversions or thermal convection movements. 

Accident site and wreckage

The operator conducted training over Pannikin Island, a designated training area to the south-east of Archerfield Airport. The island is one of several uninhabited islands located in southern Moreton Bay, about 56 km south-east of Brisbane (Figure 3).

The instructor recalled that the Pannikin Island training area extended from sea level to 3,500 ft. The vegetation on the island is mainly mangrove shrubland, with no buildings or power lines in the vicinity, and for this reason was used for low-level training.

Figure 3: Google Earth image of location of Pannikin Island, Queensland

Source: Google Earth, annotated by the ATSB

The initial ground contact of the helicopter indicated a high‑speed, upright skid contact before further loss of directional control and impact (Figure 4). The student and instructor reported that the speed on touchdown of the helicopter was about 70 kt and was consistent with the skid mark length.

Figure 4: Photograph of impact site

Source: Student

After further impacting mangrove trees, the tail rotor assembly, including tail rotor, gearbox vertical and horizontal stabiliser, separated from the cabin and was reported as being located about 15 m north of the wreckage (Figure 5) and was largely intact. 

Figure 5: Photograph of main and tail rotor wreckage at accident site

Source: Student

Post-accident aircraft examination

The operator’s chief engineer carried out an inspection of the helicopter at the accident site before the wreckage was removed. The engineer reported that their examination found no evidence of mechanical issues that could have led to the accident. 

Recorded data

There was no onboard data recording on the helicopter to determine the flight control inputs and their effect on the helicopter during the accident. 

Recorded radar data was available of the helicopter in the training area, however due to the low-level nature of the operation, this was intermittent.

Helicopter exercises and operator’s procedures 

Helicopter pilots are taught a range of manoeuvres as part of their training and licensing requirements. These are typically categorised as either normal, advanced or emergency procedures and are detailed by the Civil Aviation Safety Authority (CASA) for different licence levels and ratings.

In addition to the standard syllabus for advanced emergencies (e.g. autorotation, tail rotor failure), advanced procedures that are not required for the CPL-H may be introduced by flight instructors to extend a student’s capability and confidence. The approved Civil Aviation Safety Regulation (CASR) Part 141 operator exposition did not include torque turns as a requirement to obtain a CPL-H.

Pre-flight briefing

Briefings prior to a flying lesson are an essential part of flight preparation and represent an opportunity to gather, mentally prepare and organise the structure of the upcoming training flight. It is also an opportunity to assess the potential risks and hazards that might arise during normal and emergency operations. Discussion on the procedures to be used in the case of unexpected events disrupting the planned flight operations are also covered, and this prepares and sets student expectations for the lesson.

While pre-flight briefings were normally conducted before each lesson covering the intended lesson sequences, on this occasion the instructor considered a detailed briefing was unnecessary due to the student’s previous experience. Before departure, the instructor and student recalled a brief discussion focused primarily on the weather, but this did not include a formal briefing covering the planned exercises and potential risks. 

The intent of the lesson was to consolidate the student’s prior training and both pilots recalled that the session was to refresh and consolidate advanced emergency procedures. 

Low-level operations 

A low-level operation is defined by regulation 61.010 of CASR as flight at a height lower than 500 ft AGL, other than when taking off or landing, and is not permitted unless the circumstances outlined in sub regulation 91.267(3) of CASR apply to the flight and the pilot is authorised under Part 61 to conduct the operation. Low‑level operations can introduce increased risk for all pilots as the proximity to terrain and reduced margin for recovery intensify the consequences of any deviation from the expected performance. There is also an increased susceptibility to adverse environmental conditions for students with less experience.

Torque turns 

A torque turn is an advanced manoeuvre to quickly complete a 180° change in direction of flight (Figure 6). The manoeuvre begins with a pitch upwards to reduce forward airspeed followed by an application of power to increase altitude. As airspeed decreases, aerodynamic stability is reduced and the increased torque induces yaw.[8] This yaw is used to initiate the turn which continues until the helicopter is facing the opposite direction. Once the turn is complete, the pilot regains airspeed, eases out of the dive and resumes level flight in the new direction. 

Figure 6: Helicopter torque turn flight sequence

Source: ATSB

The student reported that their request to conduct the torque turn training was driven by their desire to seek employment in the agricultural domain (aerial application and dispensing operations) after obtaining their commercial licence. They recalled completing several turns successfully before the accident turn. 

However, in response to the draft report, CASA stated that torque turns are not common and are actually avoided in rotorcraft aerial application and dispensing operations, in favour of accurately flown and coordinated procedure turns (see below).

No official height for conducting torque turns in training is provided by CASA, however general guidance provided for starting more advanced or complex manoeuvres is to begin at higher altitudes and reduce once competence is gained.

Procedure turns

A procedure turn is a standard course reversal manoeuvre used to change the helicopter’s direction. ICAO defines the manoeuvre as a turn made away from a designated track followed by a turn in the opposite direction to permit the aircraft to intercept and proceed along the reciprocal of the designated track. Procedure turns may be designated as being made either in level flight or while descending, according to the circumstances of each individual approach procedure. To commence the turn the aircraft would turn off track, maintain airspeed, conduct the turn and turn onto the reverse of the original course. They are sometimes referred to as ‘P turns’ as the flight track looks like a ‘P’ from above.

The Part 61 Manual of Standards competency standards for unit AA2 – Helicopter aerial application operation, specifically requires procedure turns in element AA2.6 – Manipulate helicopter at low level:

(a) manoeuvres helicopter at all speeds below 500 ft AGL, up to and not beyond the limits of the flight-manoeuvring envelope, without exceeding the operating limitations of the helicopter; 

(b) conducts coordinated, smooth procedure (P) turns with varying power settings.

Operator low-level training

In line with the CASA requirements, the operator’s exposition stated that procedure turns were required for advanced low-level training and detailed amongst other manoeuvres that the height range for the conduct of these was between 200 ft and 5 ft AGL. However, no specific minimum height was declared for procedure turns.

There was no reference for torque turns in the operator’s exposition.

Search and rescue

Search and rescue time (SARTIME) is the time nominated by a pilot for the initiation of search and rescue action. Any person deemed to be a responsible person can hold SARTIME for a pilot’s safe arrival. 

There was no regulatory requirement for the operator’s local training flights under CASR Part 91 for a SARTIME, however the absence of a formal flight following process during flight training may have implications for the operator’s duty of care during the operation.

The operator’s head of operations (HOO) reported that a range of tracking systems were used across the operator’s fleet, including satellite trackers and transponders. These devices allowed staff to monitor the location of helicopters during flight and, if a helicopter did not return within an expected time, its position could be quickly determined. A television screen located in the operator’s office displayed tracking data, however, no personnel were specifically assigned to monitor return times or to observe the radar feed.

Many of the flight training lessons were conducted from the operator’s base at Archerfield Airport, where staff could maintain direct visual oversight of helicopter movements. However, as the accident flight was early in the morning, there was only one other instructor conducting flight training and the office staff were not yet on duty.

Some helicopters in the fleet were fitted with electronic locator transmitters and others with personal locator beacons. Under CASR regulations these are mandated for flights greater than 50 NM from the departure aerodrome. The accident helicopter was fitted with a manually‑activated personal locator beacon, however the instructor reported that they were dazed immediately after the accident and did not prioritise the activation.

Safety analysis

Introduction

An instructor and a student were conducting advanced emergency training in a Robinson Helicopter Company R22 (R22) helicopter, registered VH-8BW, at Pannikin Island in Moreton Bay, Queensland. Near completion of the commercial helicopter pilot lesson, the instructor and student agreed to conduct torque turns, an advanced helicopter handling manoeuvre that was outside of the training syllabus. After conducting several torque turns, the helicopter entered an increased low nose attitude during recovery at low altitude which resulted in a collision with terrain and dynamic rollover. 

This analysis will consider decision‑making of the instructor and student and the instructor’s recovery as factors in the accident. 

Decision-making

Instructing is a complex task and flight instructors must balance the benefit to the student’s learning and experience with safe margins of operation in a dynamic and sometimes rapidly changing environment. 

The decision to conduct torque turns was only discussed between the instructor and the student during the flight.

Instructors consider several factors such as student performance, recent progress and training objectives when making in‑flight decisions to alter or vary the training flight plan. While instructors can adapt lessons to suit the student’s progress, deviations from planned activities should be underpinned by clear safety considerations, briefings and effective risk management. 

Effective instructional decision-making balances educational value with operational risk. The instructor assessed the student to be capable of performing the manoeuvres based on their recent progress and performance during the lesson and having completed many previous training hours together. However, this assessment was done during the training flight, limiting the time available for the instructor to fully consider the benefits and risks (including height to conduct the training – see below).   

The benefits of conducting a pre-flight brief of the lesson, especially where training operations are conducted in emergencies is well-established. Such a briefing reaffirms standard operating procedures, promotes predictable behaviour, and sets expectations (Sumwalt and others, 2010). 

The torque turns were not part of the syllabus and were not necessary for the lesson. However, if the decision to conduct them had been agreed before flight, this would have allowed for a full ground briefing to establish the torque turn procedures, discuss the conduct of the manoeuvre and ensure a common understanding of how the practise turns would be conducted. 

Manoeuvre height

Torque turns were outside of the advanced emergency lesson for the operator’s commercial pilot training syllabus and consequently no procedure was identified in the training materials for conducting them during training. The absence of a defined procedure places the reliance on the instructor to become the risk control. In this case there was an increase in risk as the manoeuvre was conducted at a height that reduced the available safety margin and limited the opportunity for recovery when the helicopter entered an undesired state. By contrast, if the manoeuvre had been initiated at a higher altitude, the increased height would have provided more time for the student and instructor to identify, intervene and recover from the undesired aircraft state. Increased altitude when practising a high-risk manoeuvre with a student would allow time for corrective control inputs from the instructor to avoid collision with terrain. 

Beginning the low-level torque turn exercise at 50 ft AGL, rather than starting higher and working down as the student’s capability improved, increased operational risk.

Instructor recovery

During the torque turn, the helicopter exited the manoeuvre in a lower than expected nose attitude. Instructor intervention is a critical control in flight training and is often the final opportunity to regain control of the helicopter. Although the instructor took over control as soon as they recognised the rapid descent rate, the low height on exiting the torque turn limited the time available to arrest the descent before ground contact occurred. Environmental conditions may have further reduced the safety margin and complicated the low-level recovery.

Due to the high speed of the helicopter and approaching vegetation, the instructor likely attempted to slow the helicopter using rear cyclic (as would be normal practice when airborne), however, after skid contact with the ground in an upright attitude, this likely resulted in the main rotor disk flexing and making contact with the tail boom. This resulted in the severing of the tail boom by the main rotor blades, loss of torque control and the front left skid digging into soft soil, leading to a dynamic rollover. 

SARTIME 

The operator had no formal process for monitoring the return of training flights. While many operations were conducted within line-of-sight or in close proximity to the operator’s base, this informal system provided limited assurance that an overdue returning training flight outside of the airport vicinity would be identified. In this case, had the crew been more seriously injured or rendered unconcious, the lack of formal SARTIME and flight following would likely have delayed the initiation of search and rescue efforts and substantially reduced survivability. 

Findings

From the evidence available, the following findings are made with respect to the collision with terrain involving Robinson R22 Beta, VH-8BW, 29 km north of Southport Aerodrome, Queensland, on 26 February 2025.

Contributing factors

• While conducting commercial training consolidation for low‑level and emergency procedures, the instructor and student agreed to conduct torque turns, which were outside the lesson plan and training syllabus.
• Without a procedure, the instructor conducted the exercise at an inappropriate low height, which increased risk and did not allow for a margin of error.
• During the torque turn exercise the helicopter exited the turn in a lower than expected attitude. The instructor assumed control but was unable to prevent a collision with terrain.

Other findings

• The operator had no formal process for monitoring the return of training flights. This would delay search and rescue response and reduces post-impact survivability of aircraft occupants in the event of life-threatening injuries.

Safety actions

Safety action addressing SARTIME

The operator has implemented a SARTIME procedure using an application for shared messaging between instructors and staff. For each flight, the instructor records the helicopter registration, flight details and estimated time of arrival back at base. Any delays are communicated through the group and landings are confirmed upon arrival at base or the intended destination. The procedure is documented on the pre-flight board.

Sources and submissions

Sources of information

The sources of information during the investigation included the:

• instructor of the accident flight
• student pilot
• operator CEO and HOO
• Civil Aviation Safety Authority
• Bureau of Meteorology.

References

Sumwalt, R. L. Lemos, K. A., & McKendrick, R. (2019). The accident investigator’s perspective. In Crew resource management (pp. 489-513). Academic Press.

Submissions

Under section 26 of the Transport Safety Investigation Act 2003, the ATSB may provide a draft report, on a confidential basis, to any person whom the ATSB considers appropriate. That section allows a person receiving a draft report to make submissions to the ATSB about the draft report. 

A draft of this report was provided to the following directly involved parties:

• instructor of the accident flight
• student pilot
• operator CEO and HOO
• Civil Aviation Safety Authority.

Submissions were received from:

• instructor of the accident flight
• operator CEO and HOO
• Civil Aviation Safety Authority.

The submissions were reviewed and, where considered appropriate, the text of the report was amended accordingly.

Purpose of safety investigations The objective of a safety investigation is to enhance transport safety. This is done through:  identifying safety issues and facilitating safety action to address those issues providing information about occurrences and their associated safety factors to facilitate learning within the transport industry. It is not a function of the ATSB to apportion blame or provide a means for determining liability. At the same time, an investigation report must include factual material of sufficient weight to support the analysis and findings. At all times the ATSB endeavours to balance the use of material that could imply adverse comment with the need to properly explain what happened, and why, in a fair and unbiased manner. The ATSB does not investigate for the purpose of taking administrative, regulatory or criminal action. About ATSB reports ATSB investigation reports are organised with regard to international standards or instruments, as applicable, and with ATSB procedures and guidelines. Reports must include factual material of sufficient weight to support the analysis and findings. At all times the ATSB endeavours to balance the use of material that could imply adverse comment with the need to properly explain what happened, and why, in a fair and unbiased manner. An explanation of terminology used in ATSB investigation reports is available here. This includes terms such as occurrence, contributing factor, other factor that increased risk, and safety issue. Publishing information Released in accordance with section 25 of the Transport Safety Investigation Act 2003 Published by: Australian Transport Safety Bureau © Commonwealth of Australia 2025 Ownership of intellectual property rights in this publication Unless otherwise noted, copyright (and any other intellectual property rights, if any) in this report publication is owned by the Commonwealth of Australia. Creative Commons licence With the exception of the Commonwealth Coat of Arms, ATSB logo, and photos and graphics in which a third party holds copyright, this report is licensed under a Creative Commons Attribution 4.0 International licence. The CC BY 4.0 licence enables you to distribute, remix, adapt, and build upon our material in any medium or format, so long as attribution is given to the Australian Transport Safety Bureau.  Copyright in material obtained from other agencies, private individuals or organisations, belongs to those agencies, individuals or organisations. Where you wish to use their material, you will need to contact them directly.

The occurrence

Operations from Tullah

On 10 March 2025, a Bell 412EP, registered VH-VJF and operated by Coulson Aviation Australia as HT204, was tasked with ground crew support operations on the Canning Peak fire, a sub‑fire of the West Coast fire complex in Tasmania. 

On the day of the accident Coulson Aviation Australia had 2 Bell 412 helicopters operating on the fireground. The first, HT201, was the designated winching helicopter, while HT204 was one of a mixed fleet of firebombing¹ helicopters. There were 6 helicopters (3 x AS350, 1 x Bell 412 (HT204), 1 x Bell 212, 1 x BK 117) firebombing with buckets (bucketing)² within a 2-km proximity of each other intermittently. The helicopters were distributed across 4 separate circuits, with 5 separate dip points, separate individual and shared targets and some shared ground crew.

In addition, the air attack helicopter, an AS350 designated as Firebird732 (FB732) was on scene overhead. The air attack supervisor (AAS),³ who was in FB732, reported that HT201 was tasked with the insertion of crews into the fireground, return to Tullah and await further instructions. HT204 was tasked to firebomb in support of the crews HT201 had inserted with a 150-ft longline and 910 L bucket.

At about 0830, the Tasmanian Fire Service briefed pilots on the weather and taskings for the day while at Strahan Airport. Prior to departure, the pilot completed a flight risk analysis tool (FRAT) to assess and record operational risk for the flight to Tullah. 

At about 0900, both helicopters departed Strahan Airport for Tullah, which was the designated staging area⁴ for the activities. Approximately 25 minutes later both helicopters arrived at Tullah. The pilot of HT204 reported shutting down the helicopter and waiting until they were required for firebombing operations.

At about 1215, HT204 was tasked with firebombing operations in direct support of ground crew who were undertaking hot and cold trailing.⁵ The pilot reported they did not complete an additional, or update their original, FRAT to reflect this change in task.

At 1226 local time the pilot departed Tullah for hotspots located west of the Murchison River on the south‑east end of the fire. The pilot was the only person on board. The pilot reported that the weather conditions on departure were calm, with a temperature of 22°C and light, variable winds. 

When reaching the designated dip site⁶ area, the pilot completed one fuel cycle, approximately 10 bucket loads, under relatively stable conditions. The pilot described the specific dip site they chose as a narrow section of the Murchison River, approximately 50–60 m wide, with tall trees lining the bank (see Dip site). The drop zone for these was located approximately 1 km west of the dip site. 

The pilot then returned to Tullah to pick up an air crew officer (ACO) at 1400 and continued onto the designated air base in Zeehan, which had a sports oval being used as a refuel base (Figure 1).

Figure 1: First fuel cycle and return to Tullah

Operations from Zeehan and occurrence

During the approach to Zeehan, the pilot noted a significant weather change, with winds shifting to a westerly direction at approximately 30 knots. The pilot reported they did not complete an additional, or update their original, FRAT to reflect this change in condition (see Flight risk analysis tool (FRAT)).

While on the ground, the ACO was dropped off and the helicopter was refuelled for the next cycle. At about 1440 the pilot departed Zeehan and returned to the Canning Peak fireground. 

The pilot recalled that various dip sites along the river looked similar. As indicated by the flight data (Figure 2), the pilot initially conducted a descent into a different dip site, which they were not intending to use and had not used on the days prior, located further south along the river (see Dip site). The pilot recognised this and undertook reconnaissance to find the intended dip area. Once reaching the dip site, the pilot resumed bucketing operations, and 2 bucket loads and drops were conducted. 

Figure 2: Second fuel cycle flight path

The pilot reported that, at about 1525, while filling the third bucket load, the helicopter was in a stable hover at about 150 ft above the dip site with the bucket submerged, when the helicopter unexpectedly sank. The pilot recalled it sinking approximately 50 ft. The pilot reported initially raising the collective before quickly realising the power available would not arrest the descent, then lowering the collective and applying forward cyclic to transition to forward flight and stabilise the helicopter, while aiming to avoid an over‑torque event. 

During this manoeuvre, the pilot reported that they were unable to jettison the longline, which they attributed to pressing on the button’s ring guard instead of its centre, and the longline subsequently became taut. The helicopter came to an abrupt stop and the pilot heard a ‘loud clunking noise’. The pilot reported they recovered the helicopter to a stable hover at about 30 ft (initially reported to Coulson Aviation Australia as 10 ft) above the water when discussing the event with the ATSB. They recalled they initiated rearward flight to release the water and retrieve the bucket from the river. The pilot observed an engine torque split⁷ and once the bucket and longline were recovered they initiated a climb to clear the surrounding trees. 

The pilot reported that once they had cleared the trees, the torque split then returned to even. They conducted a range of tests to assess controllability and engine performance, including minor adjustments to engine torque. The pilot noted that the tail rotor control pedals felt stiff, however they continued to provide adequate input for sufficient helicopter control. 

The pilot contacted the AAS on the fire common traffic advisory frequency (FCTAF) stating they had a bucket issue and a flight control issue. 

The pilot of FB732 (with the AAS on board) oriented the helicopter to view HT204. The AAS recalled HT204 gaining altitude and tracking away from the Murchison River, over the fire, heading on a bearing south‑west uphill and back to Zeehan. They noted the helicopter was ‘climbing slowly and appeared to be flying irregularly’ during this period. They reported they had not seen the occurrence as the dip site HT204 was using was beneath and behind the air attack helicopter. 

The AAS contacted the pilot on the FCTAF. The pilot of HT204 reported issues with the helicopter pedals and when asked what their intention was, the pilot reported they were heading back to Zeehan. The AAS acknowledged this and reported they would follow HT204 back. 

The pilot of HT204 reported they had assessed available landing options but elected to continue toward Zeehan rather than commit to an off-field landing. This decision was influenced by a previous experience where a potential landing site, assessed from approximately 500 ft, had appeared suitable but proved unsuitable upon reaching around 30 ft. The pilot considered that committing to a landing carried the risk of being unable to complete it safely.

The AAS and pilot of FB732 discussed possible landing options nearby. However, given the impaired controllability of HT204 and the smaller prepared landing areas on the fireground, they agreed the best action would be to return to Zeehan. 

The pilot did not jettison the longline and bucket following the recovery, and the load remained attached to the helicopter for the remainder of the flight. The pilot reported that, at the time, they did not consider they needed to release the bucket as the helicopter remained controllable. The AAS also observed that the bucket remained attached as the helicopter departed the area and during the return flight toward Zeehan.

Return flight

The pilot reported continuing the flight toward Zeehan with a plan that, should the situation deteriorate further, they could divert to Strahan Airport as an alternative. During the return flight to Zeehan, the recorded groundspeed was between 65 and 70 kt⁸. This would reduce strain on the tail rotor by operating the helicopter at a lower power setting. Apart from the tail rotor control pedal stiffness, the pilot reported that there were no control difficulties. Pedal inputs were minimised to avoid exacerbating the condition.

The AAS described the helicopter’s flight en route to Zeehan as appearing abnormal. In addition to the notably reduced speed, the AAS stated, HT204 appeared to be yawing from side to side and maintained a lower height than would normally be expected. They reported that due to the pilot sounding stressed they did not contact the pilot further. The HT204 pilot reported the helicopter was in stable flight with no yawing en route to Zeehan.

The AAS recalled contacting the air base manager at Strahan and the air operations manager and advised them of an unknown mechanical malfunction with HT204. They reported that the pilot was still in control, and that they were following HT204 back to Zeehan.

The pilot of HT204 reported that about halfway back to Zeehan, they considered diverting to Strahan if the pedal stiffness worsened. However, as the situation remained unchanged, they continued towards Zeehan.

Landing at Zeehan

The pilot of FB732 made in inbound call for both helicopters on the Zeehan FCTAF. At about 1548, the pilot of HT204 conducted a shallow approach to set up a vertical descent to the oval in Zeehan with the bucket and longline attached. During the landing sequence, the ACO secured the bucket and longline and moved it away and forward of the landing zone. The pilot then released the line and allowed the helicopter to sink, using available power,⁹ which resulted in what they stated ‘appeared to be a satisfactory landing with minimal pedal input required’.

The AAS reported they thought it was strange the pilot had not jettisoned the bucket and longline on approach given the apparent control issues. They described the landing as slow and awkward noting ‘it looked obvious there were control issues.’

After landing, during the shutdown procedure, the pilot was unable to roll the engine throttles back to idle. While disconnecting the longline from the hook, the ACO observed significant damage to the helicopter’s fuselage structure aft of the external hook. 

The AAS directed HT201 to fly to Zeehan, so its crew could debrief and support the pilot of HT204. The pilot of HT201 recalled that they landed and shut down their helicopter in Zeehan. They observed HT204 still running and the pilot underneath the helicopter assessing damage. They discussed the issue of not being able to roll the engines back and the pilot of HT201 suggested pulling the helicopter’s T-handles.¹⁰ The T-handles were then pulled to shut down the engines. 

Examination of the helicopter identified damage to the engine control system, external cargo hook system, fuselage structure, and associated systems. The substantial damage identified is discussed in the Helicopter damage section. 

Context

Pilot information

Qualifications and experience

The pilot held a Commercial Pilot Licence (Helicopter), with a single engine class rating for helicopters. They held type ratings for the Bell 212, 412 and 427. The pilot’s total aeronautical experience was over 3,000 hours of which 120.6 hours were on the Bell 412. In the previous 90 days the pilot had flown 50.3 hours, all on the Bell 412. 

The pilot was qualified to conduct helicopter firefighting operations and had low‑level and sling operation ratings.

The pilot last completed an aerial application proficiency check, which included a low‑level helicopter flight review, on 11 November 2024, which was valid for 12 months. 

Training

The pilot commenced employment with Coulson Aviation Australia in October 2024. As part of their initial training, the pilot completed a 2-week flight training course on the Bell 412 in the United States with FlightSafety International, which included approximately 18 hours of simulator training.

Following their return to Australia, the pilot completed camera training¹¹ on 9 November and subsequently had an aerial application rating proficiency check (APC) conducted on 11 November. The APC was conducted in accordance with the requirements of the Civil Aviation Safety Regulations (CASR) Part 61 and was required to be completed every 12 months. The check was conducted in the context of company firefighting operations and included a type rating flight review, a low-level flight review, and a sling load line check applicable to firefighting bucket operations. The APC also satisfied the requirements of a flight crew operator proficiency check (OPC) for Coulson Aviation Australia.

The pilot reported that the sling load line check was conducted at Kemps Creek and involved completing approximately 4–5 bucket runs, including operations requiring avoidance of a powerline in the area. The pilot stated that the training did not include any scenario-based elements. They also reported that, following completion of the APC, they did not conduct any further bucketing operations until deployment to the fireground in March 2025, having only conducted surveillance and winching operations while working at Coulson Aviation Australia.

Medical information

The pilot held a valid Class 1 aviation medical certificate, valid to July 2025. The certificate specified that the pilot was to wear distance vision correction while flying, which was being worn on the occurrence flight.

Fatigue

The pilot arrived at the fireground on 5 March and commencing flying duties on 6 March. Between 6 and 9 March, the pilot recorded duty periods of approximately 12 hours per day, during which they flew between 5 and 7 hours daily. These duty and flight times were within the operator’s prescribed limits.

On the day of the accident, the pilot stated they awoke at about 0600 and began flight duties at approximately 0800. The pilot reported going to bed at around 2200 the previous evening and described it as a typical night’s sleep. The pilot reported feeling well rested when they woke the following morning. They indicated that the accommodation and meals provided were of a good standard.

The pilot reported taking a break at about 1400, during which they consumed food, and stated that they remained well hydrated throughout the day, with a drink available in the cockpit. While the pilot did not consider themselves fatigued, they noted they did not feel as fresh as they would immediately after waking. The pilot also reported that they did not feel the need to take an additional break, and described their level of mental fatigue as ‘very lively, responsive but not at peak’ on the Samn-Perelli 7 level fatigue scale.

Helicopter information

General information

The Bell Helicopter Company 412EP is a medium‑lift¹² utility helicopter commonly used for firefighting, search and rescue and transport operations. The helicopter had a 4-blade main rotor and 2‑blade tail rotor and was powered by 2 Pratt & Whitney PT6T-3DF turboshaft engines. The helicopter was manufactured in Canada in 2004 and first registered in Australia in 2020. The helicopter was owned by NSW Rural Fire Service (RFS) and operated by Coulson Aviation Australia. 

VH-VJF had accumulated about 4,819 flight hours total time in service and had a current certificate of airworthiness and registration. The helicopter’s technical log indicated no outstanding defects at the time of the accident. 

The helicopter’s multi-role configuration enabled it to be utilised in a range of aerial firefighting tasks, including intelligence, surveillance, and reconnaissance (ISR), winching operations and firebombing using either a belly tank or external bucket system (Figure 3).

Figure 3: NSW RFS Bell 412EP VH-VJF

On the day of the accident, the helicopter was configured for firebombing operations and was fitted with an external load system, a vertical reference door, and a 150‑ft longline attached to a collapsible Bambi bucket (see Bucket and longline). In addition to these items, the helicopter also had a forward looking infrared (FLIR) camera mounted on the left side of the helicopter above the skids.

External load system

VH-VJF was equipped with an Onboard Systems International cargo hook suspension system (Figure 4). The system attached to an existing Bell hard point and hung below the centre of gravity. The hook extended through an opening in the lower fuselage. A protective rubber ring was fitted around the edge of this opening to reduce the risk of damage if the hook contacted the opening during operation.

Figure 4: Onboard Systems International cargo hook suspension system for the Bell 412

The release of the hook could be initiated electrically or mechanically. Normal release was completed by pilot actuation of a push button on the side of the cyclic (Figure 5, left). The button was recessed and guarded by a small ring to prevent inadvertent activation. When this button is pressed the latch of the cargo hook is opened. 

In addition to the electrical release, in an emergency a mechanical release could be completed by pushing a small pedal located between the 2 tail rotor pedals at the pilot’s feet (Figure 5, right). This activated a manual release cable attached to the cargo hook.

Figure 5: Electrical and mechanical external load release systems

The cargo hook suspension system was required to be inspected annually or after 100 hours of external load operations, whichever came first. The system was last inspected on 20 February 2025 and was deemed to be a serviceable condition. 

The cargo hook manual required pilots to test the electrical and manual release system prior to conducting flights for the day. The pilot recalled testing both the electrical and mechanical release the morning of the accident, and both systems were in working order. 

The pilot recalled that when landing at Zeehan after the accident, the electrical release was used to drop the longline and bucket without issue. Coulson Aviation Australia reported that both the electrical and mechanical releases of the hook were tested following the accident. Both were reported as serviceable. 

Vertical reference door

The Bell 412EP helicopters were usually flown from the right‑hand seat. This configuration is used when pilots are conducting either winching or ISR operations. During bucketing operations, pilots operated the helicopter from the left‑hand seat. VH‑VJF was modified with a vertical reference door in accordance with a Transwest vertical reference door supplemental type certificate. This included a bubble window, viewing slot, and instruments and warning lights installed in the door to provide visibility and instrumentation for operations from the left‑hand seat (Figure 6).

Figure 6: Instruments and warning lights installed in the vertical reference door

In addition to the instruments and warning lights, the type certificate required the installation of several systems to be placed on the left side of the helicopter. This included: 

• a force trim switch, cargo release switch and automatic flight control system (AFCS) release switch mounted on the left cyclic
• the torque meter and tachometer from the left instrument panel moved to the vertical reference door
• an additional mechanical cargo release pedal between the left side pedals.

During the occurrence flight and other firebombing operations, the pilot was operating the helicopter from the left‑hand seat, utilising the left cyclic and referencing the flight instruments through the vertical reference door. While conducting the water collection, the torque indicator was visible through the bubble window and could be monitored during the lift. 

Bucket and longline

The bucket was a Bambi Max bucket with a nominal capacity of 240 US gallons (910 L). The empty weight of the bucket was 137 lb (62 kg) and the maximum gross weight was 2,140 lbs (970 kg).

The bucket spoke system consisted of a series of radial support lines (spokes) that connected the upper attachment point of the bucket to the bucket body. The spoke system provided structural support, maintained the bucket shape during flight, and distributed the loads associated with lifting and manoeuvring the bucket. The spoke assembly was connected to the helicopter via the longline, which attaches to the bucket’s upper fitting (Figure 7).

Figure 7: Bambi bucket spoke assembly and longline attachment

The bucket and longline were attached to the external load system via a bow shackle (Figure 8, left). The collapsable bucket was equipped with multiple drop valves to allow pilots to split water loads into multiple drops (Figure 8, right), and the bucket also had the capability to shed the load rapidly.

Figure 8: Longline attachment and Bambi Max bucket split release system

The longline was constructed from high-strength synthetic fibre rope selected for its high tensile strength, low stretch characteristics, light weight, and resistance to heat and abrasion. The line incorporated an electrical cable along the line to control bucket release. 

Forward looking infrared (FLIR) camera

FLIR cameras are used on aerial firefighting aircraft to provide thermal imaging of firegrounds, enabling crews to detect heat sources through smoke, darkness, or challenging terrain. This capability allows operators to identify fire hotspots, monitor fire spread, and support decision-making for resource deployment and suppression strategies.

On VH-VJF, the FLIR camera was mounted on the left side, just above the skids. Coulson Aviation Australia stated that although the cameras could be removed, they would generally be kept on the helicopters throughout all operations, enabling crews to be quickly re-tasked for ISR missions. As described in the next section, some pilots indicated to the ATSB that the camera could partially obscure visibility during bucketing.

Visibility

The ATSB interviewed 7 pilots with experience conducting longline bucketing operations on the Bell 412s at Coulson Aviation Australia, including the occurrence pilot. Five of those pilots reported that the field of view from the cockpit during these operations was poor, with visibility of the suspended load restricted at times. When leaning out of the cockpit to look down along the longline, their view was impeded by both the flight step and, where fitted, the FLIR camera. This visibility issue was noted as recently relevant by one pilot who had operated on the Canning Peak fireground in the week prior to the occurrence, who reported taking a steeper approach into the dip site on that occasion. 

Coulson Aviation Australia’s internal investigation also recorded that multiple flight crew identified the presence of the flight step and FLIR camera during external load operations as a safety concern, as these features could obstruct the pilot’s line of sight to the bucket. Coulson Aviation Australia advised that these concerns had not been previously reported by pilots through the occurrence reporting system or otherwise formally raised through the internal SMS. Similarly, impeded visibility had not been identified or elevated by pilots through the FRAT.

The flight step protruded into the downward field of view, while the FLIR camera extended externally by approximately 50 cm, obstructing the pilot’s downward line of sight from the left seat (Figure 9). This was most pronounced during the approach, when the bucket trailed behind the aircraft and moved underneath as speed reduced, limiting the ability to visually acquire the load. Pilots described the need to adopt modified seating or head positions to maintain sight of the bucket. In addition, pilots reported that flight step length varied based on which aircraft was being flown (see Bell 412 Fleet).

Figure 9: Field of view with both the long flight step (left) and short flight step (right), looking down from the left seat from inside the bubble window

Pilots emphasised that visual contact with the load was important for assessing height, position, and obstacle clearance. They reported that while radar altitude and altimeter indications were used as supplementary references, they did not provide the same level of situational awareness as direct visual observation of the load. Consequently, any degradation or loss of visual cues increased the difficulty of accurately judging the load’s position and clearance from obstacles.

The flight step and FLIR camera configurations were approved and certified through regulatory mechanisms. Coulson Aviation Australia advised there was no limitation or restriction contained within the applicable aircraft flight manual supplement that prohibited or restricted external load operations as a consequence of the downward visibility obstruction associated with these approved configurations.

Helicopter damage

The ATSB did not examine the helicopter or equipment. Coulson Aviation Australia conducted an examination of the helicopter the morning after the occurrence. The following damage was identified:

• The #1 (left) engine control tube had sheared at the lower tube end bell crank, resulting in a complete loss of pilot input to the engine.
• The #2 (right) engine control tube bell crank attachment bracket had detached from the helicopter structure’s securing rib, restricting pilot control of the engine.
• The tail rotor control rod on the right side of the external hook’s bell crank airframe attachment had broken away, with the primary structure also separated.
• The main transmission oil cooler pressure line exhibited significant contact damage, however, no splits or leaks were identified.
• The fuel tank interconnect braided hoses sustained minor contact damage.
• Multiple aft fuselage drain lines were damaged.

Images of the helicopter indicated that the structural fuselage honeycomb aluminium skin, adjacent to and aft of the external hook, was deformed and had separated from the primary structure (Figure 10).

Figure 10: Helicopter aluminium skin damage

Images revealed indications consistent with contact between the longline and the rear cross tubes of the helicopter. In addition, inspection of the cargo hook and associated bumper stop components identified signs of impact damage (Figure 11).

Figure 11: External load system damage

In addition, the ring in the middle of the Bambi bucket spoke assembly was fractured in 4 places (Figure 12).

Figure 12: Damage to bucket spoke assembly

Multiple instances of what was reported as cable ‘bruising’ and stretching were reported to have been observed on the bucket cable wiring and attachment eye ends.  

Weather information

At the time of the helicopter’s departure from Strahan Airport, the meteorological aerodrome report (METAR)¹³ reported wind west‑north-west at 6 kt, visibility greater than 10 km and no cloud cover. 

The Tasmania Fire Service (TFS) incident action plan indicated that weather on the Canning Peak fire would change from north-westerly to west-south‑westerly by mid‑afternoon with winds reaching 10 kt by the afternoon (Table 1).

Table 1: Canning Peak fire forecast

The air attack supervisor (AAS) reported that on the day of the accident the wind was calm, there was no turbulence and ‘great’ visibility. A change in wind direction was noted from mid-morning, changing from northerly to south-westerly, however this was expected based on the forecast. They recalled the area in which the aircraft were working in was protected from south‑westerly winds due to the topography. They reported no feedback from pilots regarding the weather or any other environmental conditions on the day. 

The pilot of HT201 reported there were blue skies and fairly light winds on the day of the accident. They recalled that although they were not bucketing on this day, during previous bucketing operations in the same valley, the wind conditions were variable and the wind would shift ‘back and forth’. 

The Canning Peak fire weather station atop Mt Inglis, approximately 15 km north of the operating area (Figure 13), recorded south‑south-westerly winds at 5.7 kt gusting to 11.4 kt at the time of the accident. 

Figure 13: Canning Peak fire weather station location to dip site

Fireground information

The West Coast fire complex originated from 24 individual ignitions sparked by dry lightning strikes on 3 February 2025, across Tasmania’s remote western and north‑western regions. These separate fires were grouped into a single complex for coordinated management due to their proximity, shared weather influences, and overlapping spread patterns. 

There were 4 primary firegrounds that accounted for the majority of the burnt area, including the Canning Peak fireground. Each represented a distinct sector with unique terrain, vegetation types, and behavioural characteristics. These firegrounds collectively contributed to the complex’s total footprint of nearly 95,000 hectares.

The Canning Peak fireground was located in an elevated and vegetated zone close to the Cradle Mountain area. This sector featured rugged alpine-influenced terrain that complicated direct ground access, leading to heavy reliance on aerial suppression tactics. 

Dip site

The AAS, who was part of the interagency operation (see Tasmania Fire Service), selected and allocated dip areas based on the area of the fireground being worked on the day. Where practicable, more open or isolated dip and drop sites were selected by the AAS to provide pilots with greater circuit flexibility and to reduce operational complexity.

The pilot reported that while the general location for a dip site was provided by TFS prior to commencing operations on the fireground, the selection of the specific section of river within that area was at their discretion. The pilot advised that they chose their dip site location on the river as it was relatively wider than other areas and they had used this section as a dip site on the days preceding the accident.

HT204’s dip site was approximately 700 m from the next nearest dip area being used by other helicopters.¹⁴ The dip site was approximately 1 km south‑east of the drop zone, along the Murchison River. Google Earth images indicate the river width at the dip site was approximately 20 m (Figure 14).

Figure 14: HT204 dip site location and allocated dip area on Murchison River

The pilot described the dip site as a narrow section of river, with tall trees lining the bank and estimated the available operating area to be approximately 50–60m wide. They reported that there were limited locations deep enough to operate the bucket, which constrained where they could dip.

The river contained very little water at the time, allowing clear visibility to the riverbed. The pilot stated that they could not recall whether any tree branches or rocks were present in the riverbed during the operation. Despite the presence of tall trees, the pilot indicated that the area was accessible to the helicopter and considered it one of the better dip sites along the river. They also noted that the turnaround time from the dip site to the fireground was approximately one minute. 

The AAS described the dip site used by HT204 as a section of river with trees approximately 30–60 m tall on either side. They recalled that the pilot was the only one using the dip area and the only helicopter in the circuit. In previous weeks, when different crews had flown the same helicopter on similar missions, no pilots had reported any problems with the dip area. Based on the dips that the AAS pilot observed, the occurrence pilot appeared to be performing them safely and adequately.

Recorded data

Data sources

Multiple independent data sources, including TracPlus satellite-based tracking logs, FlightAware Automatic Dependent Surveillance – Broadcast (ADS-B) derived positions, and OzRunways electronic flight bag recordings, were cross‑referenced and correlated to reconstruct the helicopter’s flights throughout the day and to approximate the entry and exit angles into and out of the bucketing site.

The helicopter was fitted with a TracPlus surveillance system, which provided real-time tracking through a satellite or mobile phone network. It reported position, altitude, and speed at set time periods, in this case every 15 seconds. 

The OzRunways application recorded the helicopter’s position at regular intervals of approximately 5 seconds throughout the day, capturing parameters including latitude, longitude, groundspeed, track, and truncated altitude (in 100 ft increments) where connectivity permitted. However, no position data was recorded during the bucketing operations. This absence of recorded data was likely attributable to the helicopter operating at very low levels, down to around 150 ft above ground level, while conducting repeated drops in mountainous terrain.

The FlightAware flight tracking data captured the helicopter’s en route flight to the bucketing site, as well as the subsequent low-level manoeuvres involving repeated water dips and drops. Position reports were recorded at irregular intervals ranging between approximately 8–40 seconds¹⁵ during these operations.

In addition to the TracPlus data, FlightAware was incorporated into the data analysis. The differing sampling rates and coverage characteristics of the 2 systems together produced a more complete reconstruction of the helicopter’s flight circuit during the second fuel cycle (Figure 15).

Figure 15: Second fuel cycle data from TracPlus and FlightAware

Dip data analysis

A comparison was conducted between the first and second fuel cycles to examine how the aircraft was flown during approaches to the dip site. Data from the first fuel cycle indicated that, on all approaches, the pilot maintained a descent profile not exceeding a rate of 200 ft/min when entering the dip site.

In contrast, data from the second fuel cycle showed variation between individual dips. During the first 2 dips of that cycle, the aircraft descended at rates between approximately 210 and 290 ft/min. However, on the third dip (the accident dip), the recorded descent rate exceeded 400 ft/min and at about 4 kt forward airspeed.

The third dip also exhibited a shallow run-in to the dip site, followed by a steep approach into the site itself. The pilot reported that the shallow run‑in was the result of a longer approach, following a previous drop conducted to the west on an upslope, which necessitated a wider circuit to lose altitude prior to the subsequent approach. The pilot stated that they came in on a shallower approach on this occasion and did not believe the entry into the dip site was any steeper than on the previous dips during that cycle. 

Based on the analysis of the flight data, the ATSB estimated that approximately 8‍–‍10 seconds elapsed between the onset of the uncommanded descent and the pilot’s corrective input being applied. This period likely included the time taken to detect the uncommanded descent, interpret the helicopter’s state, determine an appropriate recovery action, physically input the control response, and the helicopter to respond. 

Vortex ring state and settling with power

In helicopter operations, the terms vortex ring state (VRS) and settling with power (SWP, also known as settling with insufficient power) are sometimes used interchangeably. While the 2 conditions can produce superficially similar symptoms to the pilot, they represent fundamentally different physical scenarios. VRS is an aerodynamic condition in which the rotor system operates within its own recirculating wake. Settling with power, by contrast, is a performance limitation in which the power required to reverse the rate of descent exceeds the power available from the engine(s). 

Vortex ring state (VRS)

VRS is an aerodynamic phenomenon that occurs when a helicopter is descending at low forward airspeed (typically less than 30 kt) while simultaneously experiencing a high rate of descent (typically more than 300‍–‍500 ft/min) with power applied. As the helicopter descends into its own downwash, tip vortices grow into a circulating pattern around the rotor (Figure 16) (Wagtendonk 1996). This leads to a loss of lift and an increasing, uncommand rate of descent.

Figure 16: Established vortex ring state

The susceptibility to VRS is commonly represented using an airspeed–rate of descent diagram, which depicts a region of low forward airspeed and increasing descent rate where entry into VRS becomes more likely. This region, often referred to as the VRS avoidance region, illustrates that the condition is governed by the combined effects of low translational airflow¹⁶ and increasing induced flow through the rotor disc.

The boundaries of this region vary with helicopter type, rotor system design, gross weight, and atmospheric conditions. Manufacturer flight manuals and training guidance emphasise that maintaining either adequate forward airspeed or limiting the rate of descent reduces the likelihood of entering this condition.

The recovery from VRS as described in the US Federal Aviation Administration (FAA) Helicopter Flying Handbook (2019) involves increasing airspeed and/or reducing collective to fly out of the disturbed airflow. An alternative recovery technique, commonly referred to as the Vuichard recovery, uses lateral cyclic input combined with increased power and lateral anti-torque thrust to arrest the rate of descent and translate the helicopter laterally out of VRS (FAA, 2019) Unlike the traditional method, the Vuichard recovery focuses on rapidly stopping the rate of descent rather than exiting the vortex.

Settling with power

Settling with power (SWP) is a performance condition, not an airflow recirculation issue. It occurs when the power required to arrest a descent or maintain altitude/hover exceeds the power available from the helicopter’s engine(s). Prevention centres on strict adherence to performance charts, conservative weight and altitude planning, and maintaining a margin above hover power requirements.

The power margin available to a pilot is influenced by factors including density altitude, aircraft weight, and engine performance relative to its rated output. A reduction in available power, whether due to environmental conditions, aircraft loading, or a shortfall in engine performance, reduces the margin available before the power required exceeds the power available, increasing susceptibility to SWP.

Assuming the helicopter's engines were performing in accordance with published data, ATSB analysis indicated that the helicopter was operating significantly below its published hover out of ground effect (HOGE) ceiling of 8,200 ft under otherwise similar conditions. This indicates an additional power margin would likely have been available before reaching the torque limit. However, this analysis could not account for variables that were not recorded, including engine power setting, rotor RPM, and the actual rate of descent and airspeed at the point of onset. As such, it was not possible to estimate the helicopter's effective thrust margin, and therefore its proximity to a settling with power condition, at the time of the occurrence.

Recovering from settling with power is aided by using forward cyclic to accelerate to a best rate of climb speed¹⁷ which improves the efficiency of the rotor system and reduces the total power required to fly. If there is sufficient available height above terrain, the rate of descent can be arrested or reversed.

Reporting of the occurrence

After the HT204 pilot returned to base, the AAS sought further clarification from the pilot regarding the occurrence and the condition of the aircraft. The pilot and the crew of HT201 advised that the helicopter had sustained minor damage and that an engineer would attend to inspect the helicopter. Based on this information, the AAS formed the view that the damage was not substantial and that the helicopter would likely be unavailable for a short period while repairs were undertaken. 

The AAS also reported being unaware of the circumstances surrounding the occurrence, including the drop in altitude while attempting to collect water, beyond this initial advice. Subsequently, the AAS did not report the incident.

On the day of the accident, Coulson Aviation Australia advised the NSW RFS of the occurrence, and the NSW RFS in turn advised the TFS District Officer for Air Operations (DOAO), indicating that representatives from the NSW RFS and Coulson Aviation Australia would attend the helicopter the following day to assess the damage and determine whether repairs could be conducted at the airbase. As Coulson Aviation Australia had not advised the DOAO of the extent of the damage, they assumed the helicopter would be unavailable for a few days while repairs were undertaken.

On 10 March, Coulson Aviation Australia provided an initial notification to the ATSB with further details of the occurrence being provided on 14 March. 

Following notification that the ATSB would be investigating the accident, TFS made multiple attempts to obtain a report from Coulson Aviation Australia regarding the status and condition of the aircraft, having not previously been advised by Coulson Aviation Australia around the damage and the full extent of the occurrence. The DOAO reported that, in response to those requests, Coulson Aviation Australia advised on multiple occasions that a report would be provided. Coulson Aviation Australia submitted a written report to the TFS detailing the damage to the helicopter approximately 5 weeks after the accident.

Coulson Aviation Australia reported that, immediately following the occurrence, they notified the AAS and the airbase manager that the aircraft had been removed from service. At the time of the initial notification, the full extent and nature of the damage had not been established. Accordingly, they considered that any further information regarding the damage would have been speculative until a detailed maintenance assessment had been completed. Coulson Aviation Australia therefore advised that its approach was to communicate the information confirmed at the time and provide additional information as it became available. 

In addition, Coulson Aviation Australia advised that it provided the NSW RFS with a preliminary occurrence report within 3 days of the incident, documenting the information available following the initial assessment. The same report was subsequently provided to the TFS following NSW RFS review and approval, which was completed approximately 5 weeks after the occurrence.

The TFS DOAO reported to the ATSB that, had the extent of damage and the full circumstances of the occurrence been known at the time, TFS would have initiated an internal investigation to determine the contributing factors and whether any changes were required to the conduct of operations on that fireground, as well as to provide insight to inform future operations on other firegrounds.

Tasmania Fire Service

The response to the 2025 Canning Peak fire was led by the Tasmania Fire Service (TFS) in partnership with the Tasmania Parks and Wildlife Service (PWS). The TFS, as the state’s primary combat agency for bushfires, was responsible for incident control, fire suppression, and coordination of resources across the emergency response. The PWS provided specialist support in managing fires within reserved land, contributing detailed knowledge of terrain, environmental values, and remote-area firefighting capability, including the provision of air attack supervisors.

Use of interstate assets

On 13 February 2025, the TFS requested the deployment of 2 helicopters equipped with winch capability to support remote area firefighting team (RAFT) operations from the NSW Rural Fire Service (RFS). The request formed part of broader aerial support arrangements during the ongoing fire response.

The TFS advised that, under normal arrangements, requests for interstate firefighting aircraft are coordinated through the National Aerial Firefighting Centre (NAFC). However, when sourcing aircraft from New South Wales, requests were communicated directly to air operations personnel.

In addition to the initial tasking for RAFT operations, the TFS reported that there were verbal communications indicating that the 2 helicopters may also be utilised for water‑bucketing activities.                                                                                                         

The air attack supervisor reported that during the course of the fire suppression operations, one of the NSW RFS Bell 412 helicopters was routinely retained in a winch configuration and maintained on standby, and the other in a bucketing configuration. This arrangement reduced the need for reconfiguration between operational roles during active fireground operations. 

Incident reporting procedures (Tasmanian Fire Service)

The TFS standard operating procedures (SOPs) described the process for communicating operational information from personnel on the fireground to the incident management team. The processes for incident reporting are summarised in Figure 17. The SOPs indicated that information relevant to an incident would be initially communicated to the AAS operating over the fireground and then relayed by the AAS to either the air operations manager (AOM) or operations officer, and subsequently to the incident controller (IC). However, there was no documented guidance specifying how information was to be communicated from the pilot to the AAS, including whether it was to be provided verbally or supported by written reporting.

Figure 17: Summary of Tasmanian Fire Service incident reporting requirements 

The TFS SOPs for the reporting of incidents required that any member involved in, or becoming aware of, such an event, report it to the IC as soon as practicable. The IC was then required to notify the state air desk officer (SADO). The SOPs also required ICs and aircraft operators to submit written reports to the SADO, and outlined the minimum information to be included. The SOPs did not specify a timeframe for the submission of written reports.

Coulson Aviation Australia

Coulson Aviation is a Canadian-based aerial firefighting operator with an Australian arm known as Coulson Aviation Australia, which held a long-term contract with the NSW RFS to support bushfire response across New South Wales. In 2024, the company was awarded a 10-year contract to continue its role after already managing much of the RFS aviation fleet for the previous 5 years. Under this agreement, Coulson Aviation Australia was responsible for the management, operation, and maintenance of the entire RFS aerial firefighting fleet, including large air tankers, helicopters, and intelligence aircraft.

Bell 412 fleet

The Bell 412EP fleet consisted of 6 helicopters which had been individually acquired by NSW RFS from multiple providers globally and were each configured differently. The Coulson Aviation Australia rotary wing head of operations (RW HOO) advised that, as Coulson Aviation Australia did not own the helicopters, any configuration changes required NSW RFS approval. While a standardised fleet was preferred, a formal standardisation proposal had not been presented to NSW RFS prior to the occurrence. The RW HOO stated that they considered budgetary constraints would limit the extent to which fleet standardisation could be achieved.

General helicopter configuration

Differences across the fleet, included:

• 4 of the 6 aircraft being fitted with a longer flight step
• cockpit layouts 
• non-standardised GPS units (Coulson Aviation Australia advised that efforts were underway to align these systems)
• external load system release mechanisms 
• location of the water release button, which varied between the cyclic, collective, or both, depending on the aircraft. 

Coulson Aviation Australia advised that these differences introduced operational risk, however mitigation strategies had been implemented including discussions with NSW RFS to identify aircraft specific differences and assess their operational implications. It further reported that, following other incidents, it was in the process of developing formal differences training for pilots and compiling a detailed differences list for NSW RFS to support increased standardisation. 

Asset allocation and configuration for missions

Coulson Aviation Australia stated that all 6 helicopters were considered multi-role aircraft. These aircraft could be configured to undertake ISR, winching, and aerial firefighting operations, including both belly tank and external bucket configurations. They stated that when tasked, aircraft were expected to be capable of performing all available mission types, reflecting their multi-role design and intended operational flexibility.

The allocation of helicopters to tasking locations was determined by NSW RFS and was primarily influenced by proximity to the fireground. Coulson Aviation Australia responds to the tasking issued by the NSW RFS and provides the aircraft assigned to that task in accordance with the operational request. This included the responsibility of the configuration of the aircraft at the time, including whether the FLIR camera system was fitted when ISR capability was required. Coulson Aviation Australia reported that not all aircraft were consistently equipped with cameras, with at least one camera typically undergoing maintenance. As a result, one aircraft was generally unavailable for ISR tasking at any given time.

All 7 pilots interviewed indicated that they were not assigned to a single, fixed task when deployed. Instead, they understood there was a high likelihood of being re-tasked depending on operational requirements. Coulson Aviation Australia further noted that aircraft could be reassigned between taskings without returning to base, reinforcing the expectation that aircraft should remain capable of performing multiple roles throughout a deployment.

Within New South Wales

Within New South Wales, all helicopter taskings were coordinated through the NSW RFS State Air Desk. As the aircraft were owned by the NSW RFS, the State Air Desk was able to allocate them rapidly to firegrounds as required.

The NSW RFS advised that taskings were issued to Coulson Aviation Australia via a dispatch form, which included details of the location and the operational capabilities required. This was supported by verbal coordination between the NSW RFS and Coulson Aviation Australia to ensure that an appropriately configured aircraft, along with a suitable crew, was assigned to meet the operational requirements.

Interstate

When aircraft were requested by other jurisdictions, the requesting state engaged directly with the NSW RFS State Air Desk. The NSW RFS reported that requesting agencies provided detailed tasking information, including:

• required aircraft capabilities (such as winch capability)
• a point of contact
• intended area of operations
• expected deployment duration
• task specialist personnel requirements
• logistical support arrangements such as accommodation and fuel.

Using this information, the NSW RFS generated a booking with dispatch information provided to Coulson Aviation Australia including:

• movement authority
• aircraft registration and call sign
• required configuration
• assigned task specialists
• deployment period
• operational location
• jurisdictional point of contact
• expected operational tasks
• logistical arrangements.

The NSW RFS noted that detailed operational briefings for aircrew were typically provided by the requesting agency upon arrival at the deployment location.

The RW HOO stated that, consistent with operations within New South Wales, aircraft deployed interstate were expected to retain full multi-role capability, even where the requesting jurisdiction had specified only particular mission types. They further advised that they generally contacted the requesting jurisdiction to obtain additional information about the tasking. During these discussions, the requesting jurisdiction would sometimes request additional aircraft capability to support the operation. 

When asked about the removal of the FLIR camera system prior to interstate deployment if ISR wasn’t required, the RW HOO indicated that it was not preferred, as the understanding was that contractually the aircraft were required to remain fully capable of multi-role operations. For removal during interstate deployments, an engineer¹⁸ was required to carry out the task. They also noted that the cameras were fragile and that repeated removal and installation could increase the risk of damage. In addition, the associated transport cases were large and would need to be transported interstate.

Coulson Aviation Australia advised that prior to the occurrence, there was an understanding within the organisation that the NSW RFS contractual requirement for full multi-role capability meant that role equipment, such as the FLIR system, was required to remain fitted to the helicopter for all operations. However, the contract required role‑specific equipment to be readily available and capable of being fitted when required, rather than continuously installed. 

Tasmania Fire Service request

The TFS originally made a capability request for 2 winch-equipped aircraft for the Tasmanian fire situation from the NSW RFS State Air Desk. This requirement was specified on the booking form provided by the NSW RFS to Coulson Aviation Australia and recorded within the NAFC booking system. The RW HOO reported that Coulson Aviation Australia was aware of the TFS requirement for both winching and bucketing capability, based on prior discussions with TFS personnel.

Pilot training

Overview

Coulson Aviation Australia introduced a cohort of new pilots to the Bell 412 through initial type training conducted at FlightSafety International facilities in the United States. This training was delivered entirely in a full-flight simulator and included pre-flight procedures, take-off and departure profiles, flight manoeuvres, approaches and landings, as well as normal, abnormal and emergency procedures. Emergency procedure training included VRS recognition and recovery techniques.

Following completion of simulator-based training, pilots returned to Australia to undertake further training with Coulson Aviation Australia. On return, pilots were required to complete an aerial application proficiency check (APC), which encompassed company firefighting operations and satisfied the requirements for an operator proficiency check (OPC) for Coulson Aviation Australia. It also satisfied the requirements for both a low‑level flight review and a type rating flight review. The APC was required to be completed at 12‑month intervals. While the APC could include a sling load line check, the sling check was only conducted when a firefighting bucket was being used.

In addition to the APC, Coulson Aviation Australia conducted an OPC. The rotary wing training and checking manual stated:

This OPC is used to assess a pilot conducting a typical company operation that is not covered by a proficiency check and may also be used for the purposes of remedial training. 

The OPC was both type‑ and operation‑specific and was intended to ensure competency across the operator’s range of specialised tasks.

Coulson Aviation Australia maintained 8 operation-specific OPC profiles comprising: 

• winching (water and land)
• sling operations
• belly tank operations
• intelligence, surveillance and reconnaissance (ISR)
• aerial ignition
• night vision imaging system (NVIS) firebombing
• NVIS aerial ignition
• NVIS winching.

The training and checking manual listed 3 different intervals for the OPC:

The check is type and operation specific and conducted every 24 months where needed for each operation type…

On induction and 12 monthly thereafter or 6 months after APC where required.

A diagram provided the intervals in Figure 18.

Figure 18: OPC intervals 

Source: Coulson Aviation Australia

The recurrent proficiency check requirements of the Part 138 MOS and the Part 61 of CASR APC currency requirements required operators conduct an OPC on induction, and at 6‑monthly intervals thereafter. It allowed the initial and recurrent OPC to be conducted on the same flight as the APC or as a stand-alone check.

During the Coulson Aviation Australia’s internal investigation, it was identified that while feedback on the overall structure and quality of the training system was positive, there were deficiencies in onboarding and transitional training processes. In particular, although the accident pilot had completed an APC that included a bucketing proficiency component, they had not received formal internal ground or practical training specific to external sling bucket operations. Additionally, pilots had not been assessed in a simulated operational fire suppression environment, instead conducting basic exercises such as water collection from an unobstructed source.

Maintenance of proficiency

Coulson Aviation Australia reported that bucketing was a perishable skill requiring regular practice to maintain proficiency. It reported that pilots had limited exposure to these activities, as the majority of conducted operations were ISR missions. The operator assessed that the reduced frequency of hands-on tasking was likely to degrade pilot proficiency in these roles and increase operational risk.

Several pilots individually interviewed by the ATSB reported that the location used for initial bucketing training did not adequately replicate the operational environments typically encountered during firefighting operations. Of the 7 pilots interviewed, 5 indicated that they had limited exposure to bucketing following their initial training, with some reporting between 10 and 30 hours of bucket operations across at least 2 years of employment. These pilots attributed this to a greater proportion of ISR and winching tasks being allocated internally, while bucketing operations were more commonly conducted by other operators. As a result, pilots noted that significant time gaps between initial training and operational deployment in firefighting environments reduced their familiarity with bucketing operations in the Bell 412 and required a period of re‑adaptation when deployed to conduct that task.

Flight risk analysis tool (FRAT)

Regulatory requirements

The Civil Aviation Safety Authority (CASA) Part 138 Manual of Standards (MOS) specified that a risk assessment must consider, at a minimum:

• the nature of the operation and its specific characteristics
• the location and its particular characteristics
• the aircraft to be used, including its characteristics and performance
• the qualifications and experience of crew members
• and any external hazards likely to be encountered during the operation.

Coulson Aviation Australia requirements

Coulson Aviation Australia utilised a flight risk analysis tool (FRAT) to document and track operational risk exposure associated with individual flights and events. These assessments were completed by flight crew and captured within the safety management system (SMS). 

In a response to the draft ATSB report, Coulson Aviation Australia reported that the FRAT was expected to be used as a structured pre-flight risk assessment and that it is the pilot’s responsibility for continuous dynamic risk assessment throughout a flight. A change in wind conditions, for example, would require a pilot to reassess the suitability of continuing the operation against aircraft limitations, operational requirements and their individual safety thresholds, rather than completing a new FRAT in‑flight. Where conditions exceed an acceptable threshold for continued operations, Coulson Aviation Australia stated that the expected response is to reject, discontinue or modify the task, with a task rejection recorded where further operations cannot be safely conducted.

Coulson Aviation Australia SMS required pilots to complete a FRAT prior to the first flight of the day. The SMS further required the FRAT to be re-evaluated if a maintenance or weather-related event resulted in the stoppage of operations. If the assessment was no longer considered relevant, a new assessment or an update to the existing assessment was to be completed prior to resuming operations. 

The FRATs were completed online and stored in a database. The SMS also stated that the safety manager and head of flying operations (HOFO) would regularly review the risk assessment program through the safety committee.

To support implementation, Coulson Aviation Australia provided induction training to flight crew, maintenance personnel, and safety staff. This training introduced the FRAT program, including its purpose, intended outcomes, and practical application.

Coulson Aviation Australia had a FRAT which was specific to the Bell 412. The FRAT comprised multiple sections, including:

• mission type
• mission planning
• flight crew
• weather
• aircraft airworthiness and equipment
• operating environment
• airspace. 

Each section contained a series of predefined risk factors which contributed to the overall risk score.

Selectable options within the FRAT

Coulson Aviation Australia’s FRATs covered the broad categories required by regulation, as described above. 

The mission type section listed a range of operational activities that flight crew could conduct, including:

• night visual flight rules (NVFR) 
• remote area firefighting team (RAFT)
• fire mission/external load
• intelligence, surveillance, and reconnaissance (ISR)
• search and rescue (SAR)
• state emergency service (SES) flood operations
• winch operations
• maintenance
• NSW RFS training
• Coulson Aviation Australia training. 

Pilots were able to select multiple mission types within a single FRAT. However, the FRAT did not provide a breakdown of the specific hazards or risk components associated with each individual mission type. Instead, each mission type was assigned a predefined risk score.

Pilots could select certain hazards such as low-level operations and limited landing options, and were prompted to evaluate aircraft serviceability. The FRAT did not incorporate detailed consideration of aircraft configuration or other specific aircraft characteristics relevant to different mission types, and did not contain specific assessment items relating to rotor clearance from obstacles or hazards associated with water sources used during aerial firefighting operations.

Pilot’s FRAT on the day of the occurrence

The pilot completed a FRAT prior to the first flight of the day, resulting in a score of 16. The pilot did not include relevant operating environment risk factors associated with low‑level operations, mountainous terrain, or limited landing options.

The pilot reported that the assessment was based on the initial flight to Tullah, which involved operations over relatively flat terrain. The pilot also indicated there was a possibility that tasking may occur at a different fireground closer to the coast. They noted that the FRAT should have been updated once it became clear that operations would occur at the Canning Peak fireground and later when they had observed changes in the weather conditions at Zeehan. 

In relation to the omitted factors, the pilot reported there was no clear guidance on when to select categories such as mountainous terrain or limited landing options, and that these were considered subjective. The pilot stated that low-level operations would normally be selected for activities such as winching or bucketing and acknowledged this omission was an oversight given the potential for those operations. The pilot also considered that, due to the helicopter’s capability, landing was generally possible in most areas, influencing the decision not to select limited landing options.

Inclusion of the omitted operating environment factors would have increased the risk score to 22 (see Scoring below).

FRAT usage by pilots

ATSB interviews with 7 Coulson Aviation Australia pilots indicated variability in how risk assessments were completed and applied. All pilots reported completing a FRAT prior to the first flight of the day. However, they differed in how the FRATs were used during operations, including:

• whether to complete separate FRATs for different mission types, or combining all anticipated missions into a single FRAT 
• whether to complete additional FRATs when tasking changes during the day, or when tasked to a different fireground
• when to select low-level operations
• when to select mountainous terrain
• when to select limited landing options.

For example, some pilots reported selecting the low-level operations option only for specific tasks such as aerial firefighting (including bucketing) or winching activities, where operations were routinely conducted close to the ground. In contrast, other pilots indicated that they selected the low-level option for all flights, irrespective of the planned altitude profile. These pilots reported that they used this approach to account for the possibility of tasking changes during a flight, which may require operations to be conducted at low level, and therefore ensured they were already covered within the risk assessment. Some pilots also reported uncertainty regarding when the low-level category should be applied, noting that there was no clearly defined height threshold or operational criteria to distinguish low-level flight from other operations.

Coulson Aviation Australia reported being unaware of pilots experiencing uncertainty or inconsistency in interpreting elements of the FRAT. It further stated that, as the FRAT had been developed based on prior operational experience, it was expected that pilots would have a common understanding of the terminology and intent, and that the elements would not be subject to misinterpretation.

Scoring

The FRAT allowed the assessment of risk elements through a scoring system. Two thresholds were established: a warning threshold and a critical threshold. 

The warning threshold was defined on the FRAT as a score above 22. In these cases, pilots had the opportunity to apply mitigations to individual risk elements in order to reduce the overall score. Following the introduction of a mitigation, pilots were able to determine and assign a revised score for the affected element. The SMS indicated that, in circumstances where elevated risk existed above the warning threshold, the safety manager was to be informed, and approval required for the flight to proceed without additional mitigation controls.

The critical threshold was defined on the FRAT as a score above 30. The form stated that flights exceeding this threshold were not authorised to proceed and required the pilot to contact the HOFO for further advice. In contrast, the SMS indicated that for high-risk scenarios, the safety manager and the relevant Director of Flight Operations (fixed or rotary wing) were to be notified, and approval required for the flight to proceed. 

The rotary-wing Director of Flight Operations advised that when a FRAT exceeded this threshold, they would generally be notified and would discuss the assessment with the pilot. These discussions typically focused on identifying the elements contributing to the elevated risk score, whether the level of risk was acceptable, and whether additional mitigations could be applied to reduce the risk.

The FRAT assigned predefined risk scores to a number of operational elements, including mission types. Several pilots reported that the relative risk ratings assigned to certain mission types appeared inconsistent. In particular, some activities were perceived as having comparatively low risk scores despite their inherent operational complexity. 

Four of the 7 pilots interviewed by the ATSB reported having recorded risk scores above 22, most commonly associated with NVFR operations. While most reported applying mitigations in these cases, one pilot indicated a preference to treat elevated scores as a ‘no-go’ decision point. Pilots reported that they had received minimal training regarding appropriate mitigation strategies for specific risk elements. Two of the 4 pilots advised that their selection of mitigations was primarily based on their prior operational experience and their judgement of what could reasonably be mitigated in the circumstances.

Coulson Aviation Australia reported that, through ongoing monitoring of FRAT submissions, relatively few risk assessments were noted as exceeding the threshold score of 22, and this number was lower than expected given the nature of the operations being conducted.

Monitoring of FRATs

Coulson Aviation Australia reported that risk assessment data was captured within a centralised system, which provided visibility of submissions from both Australian and United States based pilots.¹⁹ This data was reviewed during monthly safety committee meetings, where the operator tracked the number of completed assessments, as well as those assessed as elevated or requiring mitigation. It advised that, in practice, many pilots appeared to use the risk assessment as a ‘go/no-go’ checklist.

The occurrence pilot had not completed a risk assessment for the 3 days prior to the occurrence. Coulson Aviation Australia stated that, although it expected all pilots to complete a FRAT, there was no mechanism in place to reliably determine whether a pilot had not completed a FRAT prior to commencing operations. It further advised that it was not practicable to review every individual risk assessment for accuracy due to the large volume of FRATs being completed daily.

FRAT development and design

Coulson Aviation Australia’s SMS described a structured approach to risk management based on the development and use of both operational core risk profiles and mission‑specific risk profiles. These profiles were intended to be developed and applied across all departments, including maintenance, fixed-wing, rotary-wing, and business management. The SMS stated that these core and mission risk profiles for flight and maintenance operations would provide the primary inputs into FRATs.

The SMS further outlined that safety information obtained through audits, reports, and inspections was to be captured, assessed and reviewed to determine whether it identified a new hazard, a change in the existing risk context, or a degradation in the effectiveness of existing safety controls. Where applicable, this process was to result in updates to the relevant risk assessments.

Coulson Aviation Australia advised that, while the FRAT was intended to be based on mission-specific risk profiles, these mission risk profiles had not been developed. As such, the existing FRAT was developed based on operational experience.

Review and update of FRATs

The SMS described a structured approach to the continuous improvement of risk assessments through a 4-step feedback loop. Initially, core risk profiles were developed to capture baseline operational hazards. These were then supplemented by mission‑specific risk profiles, tailored to the particular characteristics of individual taskings. Together, these profiles informed the development of operational FRATs completed by flight crews.

Completed FRATs were reviewed monthly by the safety team to identify trends and recurring hazards, which would then inform updates to the process and tools.

At the time of the accident, the operator had not yet developed core risk profiles or mission-specific risk profiles as described within the SMS. The safety manager reported that updates to the risk assessment forms had been made based on insights derived from the monthly reviews. The ATSB pilot interviews indicated that changes to risk assessments did occur, however these updates were not routinely communicated to flight crew. Instead, pilots reported becoming aware of modifications only when completing a new assessment. 

Incident reporting procedures (Coulson)

Coulson Aviation Australia’s occurrence reporting framework was documented within both the operations manual and the SMS, which together outlined the requirements for reporting incidents and accidents during operations.

The rotary-wing operations manual specified that the pilot in command was required to verbally report an incident to the operator within 48 hours. In addition, pilots were required to submit a report through the Coulson Aviation Australia’s internal reporting system (PRISM), which was linked to the SMS. The manual also detailed the minimum information required to be included in these reports, supporting a standardised approach to internal occurrence documentation.

Once an occurrence was reported, the HOFO was responsible for assessing the severity and operational implications. Where necessary, the HOFO was to notify relevant management personnel within Coulson Aviation Australia and coordinate the collation and dissemination of relevant information.

The SMS further outlined requirements for external and statutory reporting, including notifications to the ATSB and CASA. It also stated that, where required, reports would be provided to a ‘client’ by the relevant contract manager. However, the SMS did not define the term ‘client’, nor clarify the circumstances under which such reporting would be required. Under the arrangements for this operation with TFS, no contract manager was appointed.

Neither the operations manual nor the SMS provided guidance on the process or timeframe for disseminating occurrence information to authorities responsible for fireground operations or air attack coordination.

Consistent with the documented procedures, all pilots interviewed by the ATSB indicated that they would report occurrences to Coulson Aviation Australia. However, 2 pilots expressed uncertainty regarding the formal reporting process for fireground incidents, with one indicating that a verbal report to Coulson Aviation Australia may be considered sufficient. All pilots reported that, in the event of an incident on a fireground, they would also advise the AAS.

Pilots consistently indicated an understanding that, once an occurrence had been reported to Coulson Aviation Australia, responsibility for further dissemination rested with Coulson Aviation Australia. This included the assumption that Coulson Aviation Australia would notify any relevant authorities overseeing fireground operations. As a result, pilots did not consider that any additional direct reporting to those authorities was required.

Related occurrences

Collision with water involving a Sikorsky S-64E Skycrane helicopter, N173AC Near Jericho, Victoria, on 28 January 2019 (AO-2019-008)

On 28 January 2019, the crew of a Sikorsky S-64E Skycrane helicopter was conducting firebombing activities when it collided with water at Woods Creek Dam, Victoria. The collision occurred following an approach to the dam to fill an external tank with water. The helicopter was crewed by 2 pilots, and a maintenance crew chief was also on board. Following the collision, all the occupants were able to exit the helicopter and swim to shore. One crewmember was seriously injured and 2 were uninjured. The helicopter was substantially damaged. 

The ATSB found that the helicopter was placed in a steep flare, which contributed to the helicopter entering vortex ring state when on approach to the dam.

Loss of control in flight involving Leonardo Helicopters AW139 helicopter, VH-YHF, near Adelaide River mouth, 38 km ENE of Darwin, NT, on 13 May 2018 (AO-2018-039)

At 2000 Central Standard Time on 13 May 2018, the crew of a Leonardo Helicopters AW139, registered VH-YHF, departed Darwin, Northern Territory, to search for an active emergency position-indicating radio beacon (EPIRB). The crew flew under night visual flight rules with support of a night vision imaging system. 

During an approach to a potential EPIRB target, smoke from nearby bushfires affected visibility and the helicopter developed an uncommanded high rate of descent. During the recovery procedure, the power demand exceeded airframe limitations. This exceedance went undetected, and the helicopter was flown on a second sortie that same evening. 

Safety analysis

Introduction

While conducting longline bucketing operations at a dip site on the Murchison River, the helicopter experienced an uncommanded descent from a hover with the bucket submerged. During the pilot's attempted recovery, the longline contacted the airframe, resulting in substantial damage to the fuselage and flight control systems. The pilot subsequently returned the helicopter to Zeehan and landed without further incident.

This analysis firstly considers the aerodynamic conditions that led to the uncommanded descent, the influence of aircraft configuration on the pilot's approach technique and visibility of the external load, and the resulting damage to the helicopter during the recovery. It also discusses the pilot's decision-making during the return to Zeehan.

The analysis then discusses several other safety factors identified during the investigation related to pilot recency, Coulson Aviation Australia’s flight risk analysis tool, and the reporting of the occurrence. These factors either contributed to the accident, or increased aviation safety risk more generally.

Uncommanded descent

Potential for downdraft

The recorded and forecast weather conditions were mild with winds that were not consistent with those typically associated with strong, localised downdrafts. While the pilot reported stronger winds at Zeehan, there was no evidence to indicate that these conditions extended to the dip area, and the local wind variability observed on previous days was also mild. A downdraft was therefore unlikely to have contributed to the uncommanded descent.

Vortex ring state and settling with power

Aside from a downdraft and in the absence of evidence of an engine or powertrain malfunction, an uncommanded descent could only be attributable to either vortex ring state (VRS) or settling with power (SWP).

During the accident dip, the helicopter was flown with a lower forward airspeed and higher rate of descent than on previous approaches during the second fuel cycle, approaching the dip site with about 4 kt forward airspeed with a rate of descent exceeding 400 ft/min. This combination of low forward airspeed and high rate of descent in a confined operating environment is consistent with a reduction in rotor efficiency associated with either VRS or SWP. Both conditions require the helicopter to be maintaining a descent, not a stable hover, with low forward airspeed and power applied.

This is inconsistent with the pilot's recollection of the helicopter being in a stable hover at about 150 ft before the uncommanded descent began. Although the pilot did not believe the entry into the dip site was any steeper than on the previous dips that cycle, the flight data indicated the third dip involved a steeper approach profile and a descent rate exceeding 400 ft/min, compared with 210–290 ft/min on the 2 preceding dips. This data indicated the helicopter had not been fully established in a hover while entering the dip site, rather continuing to descend. The data was considered sufficiently reliable to inform an understanding of the occurrence, although some details could not be determined with certainty.

It is likely that the pilot's attention was directed toward the bucket during this period. Additionally, the pilot recalled sinking approximately 50 ft before recovering to a stable hover at about 30 ft above the water, having initially reported the recovery height to Coulson Aviation Australia as 10 ft. Measured against the pilot’s reported hover height of 150 ft, this would instead indicate an altitude loss of approximately 120 ft. 

While the pilot did not report airframe vibration typically associated with developed VRS, this does not rule out entry into an incipient VRS condition, and SWP can present with a high rate of descent and reduced climb performance without significant vibration cues. Additionally, it was not possible to determine the helicopter’s position within the VRS envelope at the time, as the available data did not allow reconstruction of the combined descent rate, airspeed, and rotor flow conditions required to establish whether the helicopter was within, approaching, or outside the VRS region. The ATSB’s analysis of the likely power available, which was well above that needed to hover out of ground effect (HOGE) or arrest a descent at the occurrence location, suggests that SWP alone may not fully account for the descent. However, as this calculation did not account for several relevant unrecorded variables, including engine power setting, rotor RPM, and the actual rate of descent and airspeed at the point of onset, it was not possible to rule out SWP as a factor.

Overall, the recorded environmental conditions did not support the presence of a downdraft of sufficient strength to account for the descent. Instead, the combination of low forward airspeed, high rate of descent and a confined operating environment could have resulted in a reduction in rotor efficiency and the subsequent uncommanded descent. While available information suggests a power margin may have existed at the time, the absence of recorded engine and rotor parameters means this cannot be confirmed. It is therefore likely the helicopter was operating in conditions conducive to either incipient VRS or settling with power, or a combination of both, at the time of the occurrence.

Aircraft configuration and its influence on external load operations

VH-VJF was fitted with a FLIR camera and an extended flight step during the occurrence flight, and pilot reports indicated that visibility of the suspended load during external load operations, including bucketing, was often degraded by this type of configuration. In particular, the extended flight step was reported to impede the pilot's downward line of sight, most pronounced during the approach to a dip site as the bucket trailed beneath and behind the helicopter at reduced airspeed, making visual acquisition more difficult. The FLIR camera, which extended approximately 50 cm externally from the helicopter, could similarly obstruct the pilot's view of the bucket as well as their peripheral view of the surrounding area.

Coulson Aviation Australia’s internal investigation had also identified the presence of the extended flight step as a safety concern during external load operations due to its potential to obstruct the pilot’s line of sight. Consistent with this, some pilots reported modifying their approach profiles into dip sites, including adopting steeper approaches, to maintain visual contact with the bucket for longer.

A steeper approach profile reduces translational lift and can result in the helicopter operating at low airspeed with high power applied. If accompanied by a high descent rate, these conditions are conducive to the development of settling with power or VRS as previously mentioned. In the context of this occurrence, it is likely that the pilot’s ability to effectively monitor the bucket was degraded by the restricted field of view from the longer flight step increasing workload. 

Research has shown that increased workload can alter helicopter pilots’ visual scanning behaviour and attention allocation (Cheng and others, 2024), while sustained visual tracking tasks can result in attentional tunnelling, whereby attention becomes concentrated on the tracked object at the expense of other information sources (Van der Burg and others, 2024). In this occurrence, the restricted view of the bucket caused by the flight step and camera likely required the pilot to concentrate visual attention on tracking the bucket, at the expense of other cues. Peripheral vision is used to sense self‑motion and rate of change, including a helicopter's rate of descent. With the FLIR camera obstructing the pilot's peripheral view, this cue would have been further degraded. Collectively, these factors would have reduced the pilot's capacity to detect an excessive or uncommanded descent in a timely manner.

Accordingly, the configuration of the helicopter, specifically the routine fitment of external cameras and, in some cases, extended flight steps, adversely affected pilot visibility during bucketing operations. These modifications not only impeded direct observation of the external load but also influenced pilot technique, including the adoption of steeper approaches into dip sites. It could not be established whether the pilot’s (likely unintentional) steeper approach was made for this reason. In combination, the reduced visibility, increased cognitive workload, and attentional demands associated with visually tracking the bucket likely created conditions that were more conducive to the development of settling with power or VRS and reduced the pilot’s ability to recognise and respond to an increasing rate of descent.

This visibility limitation was not isolated to the occurrence helicopter. The NSW Rural Fire Service (RFS) B412 fleet had been sourced from multiple providers globally and there was variability in aircraft configuration across the fleet, including differences in cockpit layouts, avionics fitment, and external load systems. These included 4 of the 6 helicopters being fitted with an extended flight step, and some aircraft fitted with a FLIR camera. The visibility issue identified in this occurrence therefore reflected a condition present across several helicopters in the fleet.

Further, as the helicopters were not owned by Coulson Aviation Australia, any configuration changes required NSW RFS approval, limiting the extent to which standardisation could be achieved. 

Damage to helicopter

The uncommanded descent gave the pilot a very limited window, likely around 8‍–‍10 seconds based on the recorded flight data, to recognise the developing situation and initiate corrective action, increasing time pressure and workload.

Recovery techniques for both settling with power and VRS generally differ in emphasis, with settling with power recovery typically involving a reduction in collective to reduce induced flow through the rotor system, followed by the establishment of forward airspeed, while VRS recovery similarly relies on breaking the vortex ring by reducing collective and regaining translational airflow through forward cyclic input before re‑establishing climb power. 

In this occurrence, the pilot lowered the collective and forward cyclic in an attempt to accelerate and reduce the power required by the helicopter to regain control. This is consistent with the constraints the pilot was operating under. The rapidly developing nature of the event, the low height above ground level, and the confined dip site of approximately 20 m width (about 1.4 rotor widths) meant the pilot had little margin to respond to the emergency.

When the pilot attempted to activate the electrical cargo release, the load did not jettison, consistent with degraded fine motor control under time pressure (CASA, 2021) resulting in contact with the button's ring guard rather than the button itself. Use of the mechanical release was not a reasonable alternative, as it would have required removing a foot from the tail rotor pedals at low height and in proximity to terrain and obstacles. The requirement to maintain directional control, removing feet from the pedals would have increased the risk of further loss of control.

As the descent continued, the drag associated with the submerged bucket with the continuing forward airspeed would have increased rapidly, acting as an anchor and resisting further forward or upward vertical movement of the helicopter, consistent with the abrupt deceleration reported by the pilot.As the helicopter attempted to move forward while the bucket remained restrained by the water, the longline would have been displaced aft relative to the helicopter.

Under these conditions, the longline contacted the underside and aft fuselage structure of the helicopter, resulting in contact marks on the rear cross tubes and impact damage on the cargo hook and associated bumper stop components. Continued loading of the longline against the airframe may also have resulted in the deformation and separation of the honeycomb aluminium fuselage skin adjacent to and aft of the external cargo hook installation.

Following this, the pilot was able to arrest the descent and stabilise the helicopter in a low hover approximately 10‍–‍30 ft above the water. The pilot then released the water from the bucket and subsequently conducted a climb-out. While this sequence does not reflect a textbook application of VRS or SWP recovery profiles (which is to maintain forward speed), it is consistent with an adaptive recovery strategy in a highly constrained low-altitude external load environment. In such conditions, full execution of ideal recovery steps is often not achievable due to limited height, restricted airspace, and rapidly changing aircraft energy state. 

Return to base

Following the recovery from the uncommanded descent, the pilot climbed the helicopter clear of the surrounding terrain. At that stage, the pilot was faced with a torque split and abnormal primary flight control responses (stiffness in the tail rotor pedals), and advised the air attack supervisor (AAS) of a flight control issue. The longline and bucket remained attached but would have lifted clear of the water and emptied. 

Having regained control of the helicopter, the pilot assessed that retaining the external load did not present an immediate hazard. The extent of the damage sustained during the longline contact would not have been immediately apparent to the pilot, and the decision not to jettison the load was made in the context of the information available to the pilot at the time. Given the confined terrain and limited suitable landing areas nearby, the pilot decided to return to base rather than conduct a forced landing. 

However, the subsequent abnormal primary flight control responses suggested the helicopter had sustained potentially significant mechanical or structural damage, and the pilot could not reasonably have known the nature, extent, or implications of that damage. In these circumstances, removing the longline and bucket would have reduced aircraft loading and operational complexity while flying over terrain unsuitable for a forced landing, thereby improving overall safety margins for the return flight. While the pilot’s decision aligned with their assessment of the situation at the time, continuing the flight with the external load increased exposure to the possibility of any further deterioration of the existing structural damage or flight control system, which could have resulted in a further loss of control or another occurrence.

Recency training

The pilot had completed Coulson Aviation Australia’s initial training in November 2024 and did not conduct any further bucketing operations until deployed to the fireground in March 2025. Skills associated with external load operations, such as bucketing, are perishable and can degrade when not regularly practiced.

Coulson Aviation Australia’s training and checking system included initial qualification and periodic proficiency checks intended to assess competency across a range of operational tasks. However, these checks did not ensure ongoing exposure to all specialised activities.

Coulson Aviation Australia’s pilots could complete required checks, including an aerial application proficiency check, without receiving targeted training in sling load or bucketing operations in operationally representative conditions. Training activities were generally conducted in controlled environments and did not replicate the complexity of fireground operations, such as confined dip sites and variable terrain.

Pilot tasking was predominantly focused on other activities, resulting in limited exposure to bucketing operations. Pilot reports to the ATSB indicated that opportunities to conduct bucketing operations were infrequent, with extended periods often elapsing between operations. As a result, pilots reported they required to re-familiarise themselves when returning to bucketing tasks.

Coulson Aviation Australia recognised that bucketing was a perishable skill requiring regular practice to maintain recency, however, as there were no requirements to ensure regular exposure in bucketing operations, there was limited assurance that pilots would maintain recency in high skill degradation tasks.

Flight risk analysis tool

Pilot use and understanding of FRATs

The pilot's FRAT for the day, completed prior to the flight to Tullah, returned a score of 16, and did not include relevant operating environment risk factors associated with low‑level operations, mountainous terrain, or limited landing options. The FRAT was not updated once the pilot reached the Canning Peak fireground, or when the pilot later observed the changing weather at Zeehan. Had these factors been included, the score would have been 22 and at the warning threshold, above which required a notification to the head of flying operations and approval for the flight to proceed without additional mitigation.

The pilot reported there was no clear guidance on when to select categories such as mountainous terrain or limited landing options, and that these were considered subjective. The pilot would normally select low-level operations for activities such as winching or bucketing, and acknowledged the omission of this factor was an oversight given the potential for those operations. The pilot also considered that, due to the helicopter's capability, landing was generally possible in most areas, which influenced the decision not to select limited landing options. Although there was a requirement for daily completion, the pilot had also not completed a FRAT for the 3 days prior to the occurrence. 

ATSB interviews with the wider pilot group indicated that this variability was not isolated to the occurrence pilot. All 7 pilots interviewed reported completing a FRAT prior to the first flight of the day, however, they differed in whether to complete separate FRATs for different mission types or combine all anticipated missions into a single FRAT, and in whether re-tasking during the day warranted a new FRAT. Interpretation of the low-level, mountainous terrain, and limited landing options categories also varied between pilots, from applying them broadly and conservatively across all flights, to applying them only when certain they were warranted, with one pilot indicating that helicopters could land almost anywhere.

This variability in interpretation made the FRAT less reliable as a mechanism for identifying hazards, increasing the likelihood that operational risks were either not identified or not appropriately considered. This inconsistency extended beyond interpretation of individual categories. 

FRAT design

The FRAT provided a structured method for pilots to identify and manage operational risk. The ATSB's review of the FRAT and its application identified limitations in its design that reduced its effectiveness in capturing the risks present during the occurrence.

The CASA Part 138 Manual of Standards (MOS) required operators to ensure that risk assessments considered both the specific mission being conducted and the performance characteristics of the aircraft used. The FRAT did not incorporate aircraft-specific characteristics, including the extended flight step and FLIR camera fitted to VH-VJF. As established earlier in this analysis, these features degraded the pilot's ability to visually track the bucket and to sense the helicopter's rate of descent. Had the FRAT prompted consideration of the aircraft configuration, including known visibility limitations associated with its configuration, the pilot would have been prompted to identify and assess this risk prior to the flight.

A pilot who had operated on the Canning Peak fireground the previous week reported flying a steeper approach into a dip site as a result of similar visibility limitations. A FRAT that incorporated aircraft-specific configuration and its known effect on visibility would have provided a means of formally identifying and managing this risk, regardless of whether it had been shared informally between pilots beforehand. This occurrence illustrates how, without such a mechanism, a known risk may not be fully captured and considered by a pilot.

The FRAT's operating environment prompts, including low-level operations, mountainous terrain, and limited landing options, were applied inconsistently between pilots, reflecting an absence of clear guidance on the interpretation of these categories. In this occurrence, the pilot did not select limited landing options, having assessed that the helicopter's capability meant landing was generally possible in most areas. This assessment did not hold during the occurrence flight. Having sustained damage and assessed available landing options, the pilot elected to continue to Zeehan rather than commit to an off-field landing, reflecting uncertainty as to whether a safe landing site was achievable in the terrain being operated in. As such, the FRAT's landing options prompt did not adequately capture the risk it was intended to address.

The FRAT similarly did not include a prompt for the characteristics of the allocated dip area, such as whether the intended water source was located in a confined area. The pilot described the dip site used during the occurrence as a narrow section of river, with tall trees lining the bank, which constrained the locations available for bucketing. Without a prompt directing pilots to consider this factor, the FRAT did not enable pilots to capture the risk associated with conducting external load operations in a confined water source, despite this being a characteristic of the operating environment directly relevant to the operation.

Had the FRAT incorporated aircraft-specific characteristics, provided clearer guidance on the interpretation of operating environment factors, and captured the risk associated with specific missions (including aircraft and environmental factors that have differing effects depending on the mission type, such as the confined nature of the dip site), it is likely the pilot's risk score would have more accurately reflected the risk present on the day. More significantly, this should have prompted the pilot to consider the helicopter’s known visibility limitations and apply mitigations specific to that risk, including finding another water source, or to enter the flight with greater awareness of how the aircraft’s configuration could affect the approach to the dip site. 

Oversight and assurance of FRAT use

Coulson Aviation Australia reported that, as the FRAT had been developed based on prior operational experience, it was assumed that the interpretation of these elements would be generally understood by pilots and would not be subject to misinterpretation. However, this assumption had not been tested. While FRAT data was captured within a centralised system that provided visibility of submissions across operations in both Australia and the United States, and completed FRATs were reviewed monthly by the safety team to identify trends and recurring hazards, this review process was not structured to identify variability in how individual pilots were interpreting specific elements of the tool. As a result, Coulson Aviation Australia did not identify that, because pilots did not have a shared understanding of what individual FRAT elements meant, they were interpreting and applying those elements differently, resulting in inconsistent completion of the FRAT across the pilot group.

There was also no ongoing verification that individual pilots were completing a FRAT before commencing operations. While the occurrence pilot's non-completion is the only specific instance identified during the investigation, Coulson Aviation Australia's acknowledgement that it had no means of detecting this indicates the underlying gap in oversight was not limited to this instance, and that similar non-completion by other pilots could have occurred without being identified.

The available monitoring data also included an indication that FRAT scores may not have been accurately reflecting operational risk. Coulson Aviation Australia reported that relatively few risk assessments exceeded the warning threshold of 22, and noted that this number was lower than expected given the nature of the operations being conducted. This is consistent with the occurrence pilot's own FRAT, which returned a score of 16 due to omitting operating environment factors that, had they been included, would have raised the score to the warning threshold. Had Coulson Aviation Australia investigated why elevated scores were occurring less often than expected, this pattern of omitted risk factors resulting in artificially low scores may have been identified. No such review was undertaken. 

Collectively, these gaps in oversight limited Coulson Aviation Australia's ability to identify deficiencies in the FRAT's design and use. There was no reliable mechanism to verify completion of the FRAT, to identify inconsistency in its interpretation, or to act on and communicate signals of reduced effectiveness once observed. As a result, opportunities to identify and address deficiencies in the FRAT's design and use, and to implement improvements accordingly, were reduced. In this occurrence, these gaps meant that neither the pilot's non-completion of FRATs in the days prior, nor the omission of relevant risk factors from the FRAT completed on the day, was identified or addressed before the flight, reducing the opportunity for the pilot to receive feedback that may have prompted more complete consideration of the risks present during the occurrence flight. 

Reporting of incidents and accidents

Pilot incident reporting to the air attack supervisor

Following the occurrence, the occurrence pilot advised the interagency air attack supervisor (AAS) of the flight control issue and their intention to return to base. 

However, the account from the pilot did not include the unexpected loss of altitude during the dip. In other words, the information initially provided did not fully convey the nature and severity of the event. Without knowledge of the loss of altitude during the dip, there was reduced opportunity for the AAS to consider whether the dip area or the conditions at that location may have presented a risk to ongoing operations of other aircraft.

Coulson Aviation Australia reporting to the TFS

Following the occurrence, Coulson Aviation Australia notified the AAS, before becoming aware that the helicopter had been taken out of service. Coulson Aviation Australia advised the ATSB that this reflected a deliberate approach of communicating confirmed information as it became available, rather than providing details of the cause of extent of damage before these have been established through a detailed maintenance assessment, which it considered would have otherwise been speculative. 

This initial notification did not include the circumstances of the occurrence, including the helicopter’s loss of altitude during the dip. The TFS was separately advised of the accident by the NSW RFS, and detailed information regarding the event and the condition of the helicopter was not provided by Coulson Aviation Australia until about 5 weeks later, after the TFS sought further information to understand the circumstances and extent of damage.

While Coulson Aviation Australia’s rationale for withholding unconfirmed details of the damage is reasonable, this does not account for the absence of any report to the TFS regarding the circumstances on the occurrence itself, including the loss of altitude during the dip. This information was known by Coulson Aviation Australia at the time and did not depend on the outcome of a maintenance assessment. Its absence limited TFS’s ability to consider whether the occurrence had any implications for the safety of other aircraft operating in the same environment, independent of the helicopter’s own airworthiness. 

Due to the reporting delay after the damage had been assessed, TFS was also unaware that the helicopter had sustained significant damage and would be unavailable for an extended period of time. This reduced its ability to accurately assess the implications for ongoing fireground activities, including whether any immediate changes to operations or risk controls were required.

Coulson Aviation Australia reporting procedures

Coulson Aviation Australia’s occurrence reporting framework, as documented in the operations manual and safety management system (SMS), established processes for internal reporting and assessment of incidents and accidents. These procedures supported the collection of occurrence data and internal evaluation by management personnel. However, the procedures did not include clear requirements for the timely dissemination of occurrence information to external operational authorities involved in the activity (in this case, the TFS). This gap in procedures was reflected in this occurrence, where TFS was not provided with detailed information regarding the extent of the damage until approximately 5 weeks later. In addition, the procedures did not clearly identify who was responsible for providing occurrence information to external organisations involved in the operation.

The SMS assigned responsibility for notifying the ‘client’ to the contract manager. However, it did not define the term ‘client’ or specify when such notification was required. As a result, it was not clear whether the client referred to TFS, as the agency overseeing the aerial firefighting operation, or NSW RFS, as the aircraft owner. In addition, under the arrangements for this operation, no contract manager had been appointed. Consequently, the procedures did not clearly identify who was responsible for notifying TFS of an occurrence.

Tasmanian Fire Service reporting requirements for operators

As the agency responsible for coordinating aerial firefighting operations, TFS established the operational framework under which contracted aircraft operators conducted fireground activities. To support the consistent management of safety occurrences across multiple operators, TFS procedures included a general requirement for accidents and incidents to be reported. However, the procedures did not clearly define how or when detailed occurrence information was to be provided to TFS by pilots or aircraft operators. In particular, there was no defined timeframe for the submission of written accident and incident reports to TFS.

In the absence of clearly defined reporting requirements and timeframes, TFS relied on individual aircraft operators’ procedures to determine how and when occurrence information would be communicated. This increased the potential for delays and inconsistencies in reporting. This would reduce TFS’s ability to promptly assess occurrences, determine whether immediate safety or operational actions were warranted, and identify any broader risks that may affected ongoing aerial firefighting operations.

Findings

From the evidence available, the following findings are made with respect to the loss of control and equipment contact with water involving a Bell 412EP, VH-VJF, 57 km north‑east of Strahan Airport, Tasmania, on 10 March 2025. 

Contributing factors

• The pilot conducted a steep approach at a low forward airspeed and high rate of descent, which likely resulted in the helicopter entering an incipient vortex ring state (VRS) and/or settling with power and entering an uncommanded descent.
• While focused on the recovery, in the compressed time available, the pilot attempted to, but did not successfully, jettison the bucket and longline. The resulting load on the longline led to contact with the helicopter and damage to the airframe and flight control systems.  
• Coulson Aviation Australia's flight risk analysis tool (FRAT) did not:

- incorporate specific mission risk and aircraft-specific characteristics and performance
- fully reflect the operational environment
- include clear guidance on the interpretation of certain items. (Safety issue)

• Coulson Aviation Australia had limited assurance that the flight risk analysis tool (FRAT) was being used consistently and correctly, and had limited effective mechanisms for improvement of the FRAT and, subsequently, operations. (Safety issue)
• NSW Rural Fire Service helicopters operated by Coulson Aviation Australia were routinely configured with external cameras and some had an elongated flight step. During bucketing operations, this impeded the pilot's view and resulted in pilots adopting a steeper approach into a dip site, which increased the helicopter’s susceptibility to settling with power or vortex ring state. (Safety issue)

Other factors that increased risk

• Following the recovery, the pilot did not jettison the longline and bucket prior to returning to base, increasing the risk of further degradation to the helicopter’s controllability.
• Following the occurrence, the pilot did not report the full extent of the event to the air attack supervisor (AAS), resulting in reduced awareness of the circumstances and limiting the opportunity to assess whether the dip area was safe for continued operations.
• Coulson Aviation Australia did not immediately submit an incident report directly to the Tasmania Fire Service (TFS), which limited TFS’s ability to assess the safety of the fireground.
• Coulson Aviation Australia's procedures for the reporting of incidents and accidents did not require immediate reporting to the authority overseeing the current operation, limiting information available to support effective safety management.
• Coulson Aviation Australia pilots were completing the flight risk analysis tool (FRAT) in an inconsistent manner which increased the potential of missions being flown with unidentified and/or unmitigated risk.
• The Tasmania Fire Service’s standard operating procedures did not stipulate the immediate reporting of incidents and accidents by pilots or aircraft operators. (Safety issue)
• Coulson Aviation Australia did not have requirements to ensure pilots had adequate recency in high skill degradation tasks such as aerial firefighting bucketing operations. (Safety issue)

Safety issues and actions

Pilot currency training

Safety issue number: AO-2025-013-SI-01

Safety issue description: Coulson Aviation Australia did not have requirements to ensure pilots had adequate recency in high skill degradation tasks such as aerial firefighting bucketing operations.

Flight risk analysis tool (FRAT) design

Safety issue number: AO-2025-013-SI-02

Safety issue description: Coulson Aviation Australia's flight risk analysis tool (FRAT) did not:
- incorporate specific mission risk and aircraft-specific characteristics and performance
- fully reflect the operational environment
- include clear guidance on the interpretation of certain items.

Helicopter configuration

Safety issue number: AO-2025-013-SI-03

Safety issue description: NSW Rural Fire Service (RFS) helicopters operated by Coulson Aviation Australia were routinely configured with external cameras and some had an elongated flight step. During bucketing operations, this impeded the pilot's view and pilots reported adopting a steeper approach into a dip site, which increased the helicopter’s susceptibility to settling with power or vortex ring state (VRS).

Managing mission risk

Safety issue number: AO-2025-013-SI-04

Safety issue description: Coulson Aviation Australia had limited assurance that the flight risk analysis tool (FRAT) was being used consistently and correctly, and had limited effective mechanisms for improvement of the FRAT and, subsequently, operations.

Reporting procedures to Tasmania Fire Service

Safety issue number: AO-2025-013-SI-05

Safety issue description: The Tasmania Fire Service’s standard operating procedures did not stipulate the immediate reporting of incidents and accidents by pilots or aircraft operators.

Safety action not associated with an identified safety issue

Additional safety action by Coulson Aviation

Coulson Aviation Australia’s safety management system (SMS) manual has been updated to strengthen procedural requirements for customer and agency occurrence reporting, including clearer reporting responsibilities, communication pathways and escalation requirements. These enhancements are intended to establish stronger feedback loops between Coulson Aviation Australia and other agencies.

Glossary

Sources and submissions

Sources of information

The sources of information during the investigation included:

• the pilot of the accident flight and other pilots who conducted flights for the operator
• the air attack supervisor of the fireground
• Coulson Aviation Australia
• Civil Aviation Safety Authority
• NSW Rural Fire Service
• Tasmania Fire Service
• Tasmania Parks and Wildlife Service
• recorded data from the TracPlus unit on the aircraft
• FlightAware
• OzRunways.

References

CASA. (2021). Safety behaviours: Human factors for pilots – Resource booklet 3: Human performance. https://www.casa.gov.au/sites/default/files/2021-06/safety-behaviours-human-factor-for-pilots-3-human-performance.pdf

Cheng, L, Shen, Y-C, He, Q & Zhang, M-J (2024). Spying with a pilot’s eye: Using eye tracking to investigate pilots’ attention allocation and workload during helicopter autorotative gliding. Heliyon, vol. 10, Elsevier, no. 16, p. e35872.

FAA. (2019). Helicopter Flying Handbook (FAA-H-8083-21B). U.S. Department of Transportation, Federal Aviation Administration, Oklahoma City, OK, USA.

Van, E, Ledegang, WD, Kooi, FL, Mark & Groen, EL (2024). Attentional Tunneling in Pilots During a Visual Tracking Task With a Head Mounted Display. The Journal of the Human Factors and Ergonomics Society, vol. 67, SAGE Publishing, no. 1, pp. 63–78.

Wagtendonk, W. J. (1996). Principles of Helicopter Flight. Washington: Aviation Supplies & Academics, Inc.

Submissions

Under section 26 of the Transport Safety Investigation Act 2003, the ATSB may provide a draft report, on a confidential basis, to any person whom the ATSB considers appropriate. That section allows a person receiving a draft report to make submissions to the ATSB about the draft report. 

A draft of this report was provided to the following directly involved parties:

• the pilot of the accident flight
• the air attack supervisor
• Coulson Aviation Australia
• NSW Rural Fire Service
• Tasmania Fire Service
• Civil Aviation Safety Authority.

Submissions were received from:

• the pilot of the accident flight
• Coulson Aviation Australia
• NSW Rural Fire Service
• Tasmania Fire Service
• Civil Aviation Safety Authority.

The submissions were reviewed and, where considered appropriate, the text of the report was amended accordingly.

Purpose of safety investigations The objective of an ATSB safety investigation is to improve transport safety through: identifying safety issues for action by organisations with the responsibility for managing that safety risk influencing safety action through engaging with stakeholders, communicating findings, and fostering awareness of safety issues and concerns.  In accordance with the TSI Act, the ATSB does not investigate for the purpose of taking administrative, regulatory or criminal action, and cannot apportion blame, assist in determining liability, or, as a general rule, assist in court proceedings.  About ATSB reports ATSB safety investigation reports are developed in accordance with ATSB procedures and guidelines, and with regard to applicable international standards and instruments. Reports must include factual material of sufficient weight to support the investigation’s analysis and findings. At all times the ATSB endeavours to balance the use of material that could imply adverse comment with the need to properly explain what happened, and why, in a fair and unbiased manner. An explanation of terminology used in ATSB investigation reports is available here.   Publishing information Released in accordance with section 25 of the Transport Safety Investigation Act 2003 Published by: Australian Transport Safety Bureau © Commonwealth of Australia 2026 Ownership of intellectual property rights in this publication Unless otherwise noted, copyright (and any other intellectual property rights, if any) in this report publication is owned by the Commonwealth of Australia. Creative Commons licence With the exception of the Commonwealth Coat of Arms, ATSB logo, and photos and graphics in which a third party holds copyright, this report is licensed under a Creative Commons Attribution 4.0 International licence. The CC BY 4.0 licence enables you to distribute, remix, adapt, and build upon our material in any medium or format, so long as attribution is given to the Australian Transport Safety Bureau.  Copyright in material obtained from other agencies, private individuals or organisations, belongs to those agencies, individuals or organisations. Where you wish to use their material, you will need to contact them directly.

1. ^    Firebombing: the National Aerial Firefighting Centre states that firebombing is the dropping of fire suppressant or fire retardant from an aircraft to assist with the control or suppression of a fire. 
2. ^    Firebombing with a bucket, often known as ‘bucketing’, requires filling the bucket by lowering it into a water source, and emptying it as required at the flame front. 
3. ^    The air attack supervisor was a tactical command position, controlling the overall firefighting strategy for aircraft at a fireground. They ensured that aerial operations were consistent with procedures and the incident action plan. This included maintaining communications and providing intelligence about the fires to relevant incident management team personnel and organising aircraft at the fireground.
4. ^    A staging area is a designated location where aircraft and crews temporarily assemble and wait for tasking to active fires.
5. ^    Hot and cold trailing is a task requiring identification of hotspots along the fire perimeter, opening these areas/smouldering ground fire up with hand tools and directing pilots to drop buckets atop the burning material to prevent further fire spread.
6. ^    A dip site is a designated water source where helicopters equipped with buckets can collect water for aerial firefighting. These sites can be natural bodies of water, such as lakes, rivers, or ponds, or artificial sources like reservoirs and water tanks. Their key requirements are sufficient water depth, accessibility, and proximity to the fire to maximise efficiency.
7. ^    Engine torque split in a multi-engine helicopter is where there is an unequal proportion of total main rotor torque shared between each engine through the gearbox.
8. ^    The Bell 412EP cruise speed is 122 kt. The Vne (never-exceed speed) for carrying a bucket is 80 kt.
9. ^    A pedal jam may limit the pilot’s ability to increase power, as additional torque requires corresponding pedal input to maintain directional control.
10. ^   The T-handles are red handles which pilots pull in an emergency to shut off fuel, hydraulics, and other systems to an engine while arming the fire extinguishing bottles. 
11. ^   Each Bell 412 aircraft was capable of being fitted with a forward looking infrared (FLIR) camera. Pilots were required to complete FLIR camera training before conducting camera operators for Coulson Aviation. 
12. ^   A medium-lift helicopter is one capable of carrying moderate loads, typically between 2,000 kg and 5,000 kg. 
13. ^   METAR (Meteorological Aerodrome Report) is a routine aerodrome weather report issued at half‑hourly intervals. The report ordinarily covers an area of 8 km radius from the aerodrome reference point.
14. ^   The other dip site was further along the river, which was located closer to another fire area where aerial firefighting operations were being conducted.
15. ^   This update rate arises from the way FlightAware processes ADS-B data: although equipped aircraft transmit position messages nominally every second, the displayed track depends on signals received by a network of ground stations. In remote hilly terrain, at low altitudes down to around 150 ft above ground level (AGL), terrain shadowing, ridges, valleys, and line of sight limitations can prevent some transmissions from being captured reliably. As a result, FlightAware relies on the most consistent available reports, leading to longer effective intervals of 25–40 seconds or more during intermittent low-level reception.
16. ^   Translational airflow is the horizontal movement of air across a rotor disc which occurs when the helicopter transitions from a stationary hover into forward flight, or when it experiences a significant headwind. This horizontal airflow sweeps the turbulent vortices behind the aircraft, replacing them with clean, undisturbed air.
17. ^   Best rate of climb is the airspeed at which a helicopter achieves maximum rate of altitude gain in the shortest time. 
18. ^   For operations involving larger firegrounds, Coulson Aviation advised that an engineer may be deployed with the aircraft to provide maintenance support and assist with configuration changes as required.
19. ^   This visibility reflected the shared nature of the platform used to record FRATs across the operator’s global operations, rather than a specific operational requirement for the Australian business to monitor United States based flights.  

Investigation summary

What happened

On the morning of 25 February 2025, an Agusta A109E helicopter was conducting a marine pilot transfer operation on the inbound bulk carrier Star Coral at Blossom Bank pilot boarding ground, about 200 km north‑east of Mackay, Queensland.

At 0901 local time, during take‑off from the ship with 2 pilots on board, the helicopter developed severe vibrations. The pilots discontinued the take-off but their attempts to recover control of the helicopter were unsuccessful. The helicopter came to rest in an upright position on the helideck, having spun more than 90° counterclockwise from its initial heading, and sustaining substantial damage. The pilots and ship’s crew were unharmed.

What the ATSB found

The investigation did not identify any airworthiness issues with the helicopter and it was considered that the loss of control was not attributable to a mechanical issue. 

The ATSB found that the vibration was likely the result of the helicopter entering ground resonance, a phenomenon that dissipates when airborne, while it was in the process of departing from the ship. The discontinuation of the take‑off, after the onset of the vibration, probably resulted in the loss of control and subsequent damage to the helicopter.

What has been done as a result

The operator has added new guidelines on ground resonance to its procedures. The guidelines include procedures for recognising and recovering from ground resonance and feature case studies and video resources for training purposes. 

The operator has also developed an updated procedure for training and checking flight briefings that will include confirming the roles of each pilot, procedures for transferring aircraft control between pilots, and actions to be followed in the event of an actual emergency.

Safety message

The occurrence highlights the dangers of ground resonance, a potentially catastrophic phenomenon that can occur in helicopters with fully articulated rotor systems. Typically, the onset of ground resonance is sudden and if the pilot does not take immediate corrective action, a loss of control can rapidly occur. 

The occurrence also highlights the importance of proper coordination between a helicopter’s pilots when responding to abnormal or emergency situations. This is particularly pertinent for situations where the pilot flying is not the pilot in command. Ideally, the pilots’ individual roles and responsibilities for emergency response and flying duties should be well established prior to the flight. 

The investigation

The occurrence

At about 0730 local time on 25 February 2025, the 229 m bulk carrier Star Coral arrived at the Blossom Bank pilot boarding ground, about 200 km north‑east of Mackay, Queensland (Figure 1). The ship waited to embark a coastal marine pilot by helicopter for its inbound transit of the Great Barrier Reef via Hydrographers Passage.[1] It was in ballast and bound for Hay Point to load coal. 

Figure 1: Blossom Bank pilot boarding ground and Hydrographers Passage

Source: Australian Hydrographic Office, annotated by the ATSB

Meanwhile, at Mackay Airport, a twin‑engine Agusta A109E helicopter, operated by Flyon Helicopters and registered VH‑XUM (XUM), with 2 pilots on board, embarked the marine pilot scheduled to conduct the ship’s pilotage. The marine pilot transfer (MPT) flight to Star Coral was the first scheduled for the helicopter and its pilots that day. These flights were normally conducted as a single‑pilot operation. However, on this occasion, the pilot flying, a pilot recently engaged by the operator under its ‘in‑command‑under supervision’ (ICUS)[2] program, was under the supervision of a company check pilot (pilot supervising). 

The pilots’ plan was to transfer Star Coral’s marine pilot and then proceed to a nearby outbound ship to collect its marine pilot for return to Mackay.

At 0759, the helicopter departed Mackay Airport under the control of the pilot flying. En route, the pilots established communication with Star Coral’s master via VHF[3] radio. The master advised that the ship was rolling about 3° on its inbound heading due to a 2 m south‑easterly swell. Subsequently, the pilots requested the master to reposition the ship on a heading[4] of 270° to reduce rolling. At 0853, the pilot flying landed the helicopter on the ship’s helideck, situated on the number 5 cargo hold hatch cover (Figure 2). The marine pilot exited the helicopter and proceeded to the ship’s bridge. 

Figure 2: Landing position of VH-XUM aboard Star Coral

This figure is a representation of the helicopter’s orientation relative to the wind during the take‑off. Source: Flyon Helicopters and Star Coral, annotated by the ATSB

Meanwhile, the helicopter remained on the helideck at flight idle[5] while its pilots radioed the outbound ship’s pilot to coordinate the transfer. After some discussion, the pilots elected to keep the helicopter on the deck of Star Coral until the outbound ship had departed the compulsory pilotage area.

After about 5 minutes, as the 2 ships were about to pass each other, the helicopter pilots began conducting their pre‑take‑off checks. The pilots observed a 20 to 28 knot headwind (relative to the helicopter) and noted that the ship was rolling less than 2°. The pilot flying conducted a brief for a performance category 1[6] take‑off, which involved establishing the helicopter in a hover 35 ft above deck height before departing. Both pilots later recalled that everything seemed normal as the take‑off checks were completed. 

At about 0900, the pilot flying raised the collective[7] and observed the engine torques increasing through 50%. The pilot flying recalled the aircraft became light on its oleos as though it was ‘right at the point of lifting off’. Meanwhile, the pilot supervising was observing the outbound ship passing. A few seconds later, both pilots felt a sudden and substantial vibration. 

The pilot supervising immediately looked down at the controls and recalled that the pilot flying was holding the cyclic[8] in an abnormally aft position. Concerned that the main rotor might have struck the tail boom, the pilot supervising decided to assume control of the helicopter and took hold of the cyclic and collective unannounced. Meanwhile, the pilot flying was still attempting to lift off, unaware of the pilot supervising’s decision to take control. The pilot supervising recalled that the pilot flying had centred the cyclic and ‘must have’ lowered the collective by the time the pilot supervising took hold of the controls. In contrast, the pilot flying stated that the pilot supervising rapidly lowered the collective after the vibration started, causing the aircraft to descend from being light on its oleos and bounce heavily on the helideck.

Moments later, the cyclic became uncontrollable as the vibrations suddenly worsened into a violent, vertical oscillation of the airframe. The pilot supervising tried to stabilise the helicopter but was unable to control the cyclic movement. Subsequently, the pilot supervising elected to shut down the engines. 

The pilot supervising initially struggled to reach the engine mode switches (located on the centre console) due to the severe vibrations but subsequently managed to shut down engine number 2. The vibrations slightly eased and moments later, they were able to also shut down engine number 1. The vibration dissipated and the helicopter came to rest in an upright position on the helideck, having spun more than 90° counterclockwise from its initial heading. The sequence, from the attempted take‑off to shut‑down occurred within a period of about one minute.

Soon after, the pilots exited the wreckage and inspected the damage. The tail rotor was separated from the helicopter and had come to rest on the main deck between cargo hatches 4 and 5. Items of debris, including main rotor fragments, laid scattered on the deck along with some hydraulic fluid pooled beneath the substantially damaged fuselage (Figure 3).  

Figure 3: Helicopter wreckage 

Source: Star Coral

Apart from a thumb sprain to the pilot supervising and some bruising to both pilots’ upper leg areas, where they had been struck by the cyclic, neither were significantly injured and no‑one on board Star Coral was injured.

Context

Helicopter information

The helicopter was an Agusta A109 E variant, manufactured in 2006 and issued serial number 11684. It was registered in Australia in 2006 and began services under the operator’s Air Operator’s Certificate (AOC) in 2023. 

The Agusta A109E is a multipurpose helicopter equipped with 2 Pratt & Whitney PW206‑C turbine engines. It has a fully articulated 4‑blade main rotor system, a 2‑blade tail rotor and retractable tricycle landing gear. Able to carry up to 7 occupants, it has a maximum allowable take‑off weight of 2,850 kg. 

The helicopter was able to perform flight performance class 1 operations by adherence to Category A procedures[9]. While the helicopter was normally operated from the right crew seat, it was fitted with dual controls. A left seat‑approved pilot in command (PIC) was permitted to occupy either seat during training flights. Each set of controls could not be operated independent of the other. 

The helicopter’s wreckage was recovered from the ship 2 days after the incident and transported to a secure hangar at Mackay Airport. Prior to its removal, photographs of the wreckage and the accident area were taken. There were no indications that the main rotor or tail rotor had struck any part of the ship during the accident. 

Based on its inspections, the operator advised that no engine faults or exceedance alarms had been recorded by the helicopter’s electronic engine management systems. Additionally, no faults or defects had been reported by any of XUM’s pilots or maintainers leading up to the occurrence flight. 

Post-accident activities

There was no recorded flight data available to determine the flight control inputs and their effect on the motion of the helicopter during the occurrence.[10] The pilots’ accounts, a witness statement from the master of Star Coral and photographs of the wreckage were the main sources of evidence. 

The ATSB also sought the manufacturer’s input for this occurrence. The manufacturer advised that its preliminary assessment of the available evidence suggested that the helicopter damage appeared consistent with a ground resonance phenomenon (see the section titled Ground resonance).

The licenced maintenance organisation for XUM carried out an examination of the wreckage at the Mackay hangar. On advice from the manufacturer, the examination included inspection of specific components commonly associated with ground resonance. These included main rotor dampers, landing gear struts and tyres. The operator advised the ATSB that the inspection did not identify any airworthiness issues that may have contributed to the occurrence. The operator did not provide the inspection report or findings to the manufacturer for its assessment.

Pilot flying 

The pilot flying obtained a New Zealand commercial helicopter licence (CPL) in 2011 and started flying commercially in 2014. They converted their CPL over to an Australian CPL in 2016 and held a grade 2 flight instructor rating and a class 1 aviation medical certificate. They had experience flying both single and twin-engine helicopters in various operations. Prior to joining the operator’s in‑command‑under‑supervision (ICUS) program in September 2024, they had no previous experience on the A109E, or with marine pilot transfers (MPT). 

Under the ICUS program, the pilot was required to accrue 200 hours on the A109E before they could be assessed to fly the helicopter unsupervised on daytime VFR[11] MPT operations. At the time of the occurrence, the pilot had completed the operator’s training requirements and accrued around 50 hours flight time on the A109E. They had also been cleared to conduct unsupervised MPT operations on single‑engine Eurocopter AS350 helicopters.

Pilot supervising

The pilot supervising was the operator’s head of flying operations and held an air transport pilot (helicopter) licence, issued in 2014, and a class 1 aviation medical certificate. They were approved under the operator’s training and checking system to conduct check and supervision flights on the A109E.

The pilot supervising had been flying helicopters for 26 years in various operations and had accumulated over 10,000 hours flying time, including 3,800 hours in the A109E. They first started MPT operations in 2007 and commenced working with the operator in December 2016.   

Star Coral

Star Coral was built in 2009 by Jansu Newyangzi Shipbuilding, China, registered in The Bahamas and classed with Bureau Veritas. The ship was owned by Panormos Shipping, The Bahamas, and managed and operated by Charterwell Maritime, Greece. 

At the time of the occurrence, the 229 m ship had a mean draught of 6.51 m and the helideck height was about 18 m above the waterline.   

In a written witness statement, the master reported that:

• shortly after the helicopter started to take off, it began to pound on the helideck before it spun and the tail rotor separated

• during the sequence, the helicopter became airborne for no more than 2 seconds.

Ground resonance

Ground resonance can be defined as a vibration of large amplitude resulting from a forced or self‑induced vibration of a helicopter in contact with the ground.[12] The phenomenon is normally associated with helicopters equipped with fully articulated main rotor systems consisting of 3 or more rotor blades. It is more common on helicopters with sprung landing gear than those with skids. Typically, ground resonance occurs during landing, take‑off and ground manoeuvres.[13]

In fully articulated rotor systems, drag hinges allow each blade to advance or lag in the plane of rotation to compensate for the stresses caused by the acceleration and deceleration of the rotor hub. Such rotor systems are typically fitted with lead‑lag dampers to limit the extent of this movement and help prevent excessive vibrations. However, if for any reason one or more of the blades assumes a dragged position different to the others, the blades will move out of phase and the rotor will become imbalanced, transmitting an oscillation throughout the entire airframe.[14]

The risk of ground resonance arises when the unbalanced forces in the rotor system cause the fuselage to oscillate on its landing gear at or near its natural frequency. Ground resonance will occur if the helicopter’s damping systems are unable to compensate for the oscillation.[15] Unless corrective action is taken, the amplitude of the oscillation will increase until the helicopter becomes uncontrollable.[16] Ground resonance can also be induced when the helicopter is in light contact with the ground, if the landing gear oscillation frequency is in sympathy with the rotor head vibration.[17]

Ground resonance is commonly precipitated by the helicopter making hard or asymmetric contact with the ground, landing on a slope or sudden control movements by the pilot.[18] It can also result from other factors such as improper blade balancing and tracking, or damage to any of the blades.[19] Hard contact with the ground by some part of the landing gear when the main rotor is in an unbalanced state can further aggravate the condition.[20]

Additionally, improper maintenance of the helicopter’s main rotor and fuselage damping systems, or incorrect tyre pressures, can induce or worsen ground resonance.[21]

Flight control inputs that may induce ground resonance typically involve sudden control movements or a mishandling of the cyclic that causes the fuselage to bounce.[22]

The helicopter manufacturer advised that the application of certain cyclic commands, such as extreme aft cyclic input, could theoretically reduce the main rotor damper effectiveness in respect to the damping action on the blades’ regressive lead‑lag dynamic.

Recovery technique

The onset of ground resonance can be recognised by a rocking motion or oscillation of the fuselage while on the ground.[23] The United States Federal Aviation Administration (FAA) Helicopter Handbook[24] documented 2 widely accepted recovery techniques: 

• if the condition arises when there is insufficient rotor speed for take‑off, the only option is to lower the collective to reduce the pitch of the blades. The rotor rpm[25] should also be reduced as soon as possible.[26]

• If the rotor speed is in the normal operating range for flight, the Helicopter Handbook recommends lifting the helicopter off the ground to allow the rotor blades to rephase themselves automatically. 

Additionally, the FAA cautioned that:

If a pilot lifts off and allows the helicopter to firmly re‑contact the surface before the blades are realigned, a second shock could move the blades again and aggravate the already unbalanced condition. This could lead to a violent, uncontrollable oscillation.  

In practice, a pilot experiencing ground resonance typically has seconds to identify the condition and take corrective action. 

Similar occurrences

The ATSB reviewed several investigation reports relating to previous A109E accidents attributed to ground resonance. The incidents reviewed occurred outside of Australia between 2006 and 2025 and the contributing factors were found to be operational. Technical factors which may have caused or exacerbated ground resonance were not identified. 

Details of the previous incidents bear similarity to the occurrence involving XUM, particularly in respect to subsequent damage to the helicopter (Figure 4). 

Figure 4: Previous occurrences of ground resonance involving the Agusta A109E

Source: Leonardo Helicopters

Flight manual procedures

The A109E rotorcraft flight manual (RFM) listed fault conditions and corrective actions for emergencies and malfunctions that might occur during take‑off.

The RFM included the caution below for ground resonance within the normal flight procedure for take‑off. This was not part of the emergency and malfunction procedures.

The RFM procedure for ground resonance was consistent with recovery techniques published by the FAA. The RFM reference to the helicopter being ‘free of ground resonance’ was intended to indicate  that, like all helicopters, the A109E was designed and certified to applicable standards so that the rotor and fuselage systems do not vibrate at the same frequency under normal conditions.   

Operator procedures

As an AOC holder, the operator maintained a CASA‑approved[27] operations manual/exposition[28] to promulgate general policy and standardised procedures for MPTs on the A109E. The version of the operations manual current at the time of the occurrence was issued by the operator in November 2023.

Ground resonance

The operator’s normal procedures and emergency checklists for the A109E were derived from the RFM and did not contain any procedures related to ground resonance. 

Crew coordination in response to abnormal situations

While MPT flights were predominantly conducted by a single pilot, the helicopter was certified for operations with either a single pilot or 2 pilots. In either case, the normal procedure and emergency checklists remained the same, except that 2‑pilot checklist procedures were to be based on challenge and response. 

Normal handover and takeover procedures provided that:

In the case where the pilot flying (PF) is not the PIC and the PIC determines that the PF is not maintaining adequate control of the aircraft, the PIC may elect to take control, in which case they will signal their intention by saying ‘I have control’ upon which the PF will immediately relinquish control and the roles will reverse.

In abnormal or emergency situations, the PIC was responsible for ensuring the aircraft was flown and kept under control. The operations manual emphasised the importance of cockpit resource management (CRM) standards throughout the situation, in accordance with the below procedure:

Note: In the above procedures PM stands for ‘pilot monitoring’, NR refers to main rotor speed and IAS means indicated airspeed. 

In the context of rapidly escalating emergencies such as ground resonance, pilots have limited time to perform the procedure. 

Pilot in command responsibility during training flights

As the holder of a certificate that authorised air transport and aerial work operations, the operator was required to have in place a training and checking system (TACS). A training and checking manual (TACM) sets out policies and procedures for conducting training flights. It provided that a check pilot supervising ICUS training was to be the PIC. Check pilots were to ensure that pilots involved in training exercises were made aware of who was acting as the PIC through proper handover of control procedures. 

While an ICUS pilot might be considered the PIC for flight‑time logging purposes, the pilot supervising was deemed the PIC and responsible for the safety of the flight. The TACM stated that in the event of an actual emergency during flight training:

If the flight examiner or check pilot deems it necessary to take physical control of the aircraft at any stage after the occurrence of the emergency, then they shall do so in accordance with the hand‑over and take‑over procedures specified in the Operations Manual - Hand over and take‑over procedures.

The flight examiner or check pilot must be prepared and ready to assume physical control of the aircraft at any stage, particularly during critical manoeuvres such as during take‑off and landing.

As such, beyond the normal handover of control procedures, there were no special provisions in the TACM for the allocation of PIC responsibility and PF duties during ICUS flights. 

Briefings

For 2‑pilot operations or training flights, the operator’s procedures did not require pilots to brief who would assume PF duties in the event of an abnormal or emergency situation during critical phases of flight. 

Operational limits

Under the operator’s operations manual, the A109E was permitted to conduct daytime MPT operations up to a wind strength of 30 knots, with a maximum crosswind of 20 knots. The operational limit for ship’s pitch was 4° up and 2° down while the maximum permissible roll was 4°. The manufacturer did not have input into these operator‑defined limits. 

The pilots reported that the conditions at the time of the occurrence (20‍–‍28 knot headwind, 2° roll and minimal pitching) were within the operator’s limits for MPTs.

Safety analysis

Prior to the accident, VH‑XUM (XUM) made an uneventful landing on Star Coral and remained on the deck for several minutes without incident. There was no evidence that the helicopter was operating abnormally or experienced any instability during this period. 

Examination of the accident site did not reveal any evidence to suggest that the occurrence resulted from the main rotor or tail rotor striking the ship. Star Coral’s master reported that the tail rotor separated after the helicopter started contacting on the deck, indicating that contact with the tail boom by the main rotor was a consequential rather than causative factor. 

In that context, it is most likely that the helicopter encountered ground resonance. Assessment of the damage to the helicopter following the occurrence revealed significant similarities to that seen in previous A109E incidents attributed to this phenomenon. 

It is well established that ground resonance only arises when the helicopter is in contact with the ground. Both pilots asserted that the helicopter did not become airborne prior to the vibrations while the master reported that it became airborne for about 2 seconds. However, it is more likely this occurred after the vibration worsened and the helicopter started rebounding on the helideck. 

The exact cause of the vibration could not be determined. The possibility of causative operational factors such as flight control inputs or environmental factors could not be ruled in or out. 

Similarly, while the operator’s post‑accident inspection of the helicopter (including examination of its rotor and fuselage damping systems) did not reveal any apparent defects, causative technical factors could not be discounted.

However, the sudden lowering of the collective after the onset of the vibration likely aggravated the situation. The helicopter was almost certainly light on its oleos when the vibration began. Therefore, a sudden lowering of the collective would have caused the helicopter to come down firmly on the helideck. The United States Federal Aviation Administration (FAA) Helicopter Handbook describes that such an impact when the rotor is already in an unbalanced state can cause the rotor blades to move further out of phase, resulting in violent uncontrollable oscillations. This description is consistent with the occurrence sequence described by the pilots and the master. 

The pilots’ accounts of who lowered the collective differed. The recollection of the pilot flying that their intention was to lift the helicopter off the deck in response to the vibration was not consistent with a lowering of the collective. In contrast, the pilot supervising did not immediately identify the source of the vibration and later shut down the engines, believing the main rotor may have struck the tail boom. In this context, lowering of the collective would be a natural and expected response. Therefore, it is most likely that the pilot supervising lowered the collective while the pilot flying was attempting to lift the helicopter off the helideck.

In isolation, the immediate responses taken by each pilot following the sudden onset of the significant vibration were understandable. However, since the helicopter’s rotor speed was in the normal operating flight range, continuation of the take‑off would probably have resulted in the vibration dissipating (as detailed in the FAA Helicopter Handbook).

The operator had adequate procedures for responding to abnormal and emergency situations. However, the rapidly escalating nature of this occurrence meant that there was virtually no time to implement them. There was no requirement for the pilots to conduct a pre‑flight or pre‑take‑off brief about who would assume flying duties in the event of an emergency on take‑off. Therefore, the normal procedures for handover and takeover of control were assumed to apply.

However, the time between observing the vibrations and the loss of control severely limited the time available for a formal transfer of control between the pilots. As a result, neither of these procedures were followed and each pilot responded to the situation separately. 

Findings

From the evidence available, the following findings are made with respect to the loss of control during marine pilot transfer operations, involving an Agusta A109E, VH‑XUM and bulk carrier Star Coral, about 200 km north‑east of Mackay, Queensland, on 25 February 2025.

Contributing factors

• During take‑off, the helicopter likely experienced ground resonance, resulting in the rapid onset of significant vertical oscillations through the airframe.
• Discontinuing the take‑off after the onset of the vibration, with the rotor speed in the flight range, probably resulted in the loss of control and substantial damage to the helicopter.

Safety actions

Safety action by Flyon Helicopters 

Following this occurrence, the helicopter’s operator, Flyon Helicopters, established ground resonance guidelines for its pilots. Forming part of its exposition, the guidelines were purposed to raise awareness of ground resonance and provide information about how to recognise and respond to the phenomenon. They included response procedures and featured case studies and video resources. The procedures were to be implemented into the operator’s training framework for new and current pilots. 

Flyon Helicopters advised the ATSB that it also planned to implement an additional briefing procedure in its training and checking manual (TACM). The briefing is to be conducted by the training or checking pilot prior to any training or checking flight. It will include:

• the objectives and scope of the flight, including the intended lesson plan or sequence
• the training/checking outcomes
• the roles of each pilot, including the allocation of aircraft command responsibility
• procedures for transferring aircraft control between pilots
• actions to be followed in the event of an actual emergency
• procedures to be used in the simulation of emergencies
• procedures for the conduct of unusual operations
• the method to be used to simulate instrument flight conditions, if required
• human factors/non‑technical stills and threat and error management.

Sources and submissions

Sources of information

The sources of information during the investigation included:

• the pilots and operator of VH-XUM
• the master and manager of Star Coral
• the helicopter manufacturer, Leonardo Helicopters

References

Lemmens Y, Troncone E, Dutré S, Olbrechts T. (2012). Identification of Helicopter Ground Resonance with Multi-body Simulation, 28^th International Congress of the Aeronautical Sciences

United Kingdom Ministry of Defence, AP3456 Central Flying School Manual of Flying Vol 12 - Helicopters

Salini S N, Haradev G S, Ranjith M. (2020). Ground Resonance: Nonlinear Modelling and Analysis, 6th Conference on Advances in Control and Optimization of Dynamical Systems (ACODS), India

United States Federal Aviation Administration. (2019). Helicopter Flying Handbook

Schafer J. (1980). Helicopter Maintenance

Submissions

Under section 26 of the Transport Safety Investigation Act 2003, the ATSB may provide a draft report, on a confidential basis, to any person whom the ATSB considers appropriate. That section allows a person receiving a draft report to make submissions to the ATSB about the draft report. 

A draft of this report was provided to the following directly involved parties:

• the pilots and operator of VH-XUM
• the master and manager of Star Coral
• the ship’s flag State administration, The Bahamas
• the helicopter manufacturer, Leonardo Helicopters
• Agenzia Nazionale per la Sicurezza del Volo (ANSV)
• Civil Aviation Safety Authority
• Australian Maritime Safety Authority 

Submissions were received from:

• the pilots of VH-XUM
• the ship’s flag State administration, The Bahamas
• the helicopter manufacturer, Leonardo Helicopters
• Agenzia Nazionale per la Sicurezza del Volo (ANSV)

The submissions were reviewed and, where considered appropriate, the text of the report was amended accordingly.

Purpose of safety investigations The objective of a safety investigation is to enhance transport safety. This is done through:  identifying safety issues and facilitating safety action to address those issues providing information about occurrences and their associated safety factors to facilitate learning within the transport industry. It is not a function of the ATSB to apportion blame or provide a means for determining liability. At the same time, an investigation report must include factual material of sufficient weight to support the analysis and findings. At all times the ATSB endeavours to balance the use of material that could imply adverse comment with the need to properly explain what happened, and why, in a fair and unbiased manner. The ATSB does not investigate for the purpose of taking administrative, regulatory or criminal action. Terminology An explanation of terminology used in ATSB investigation reports is available here. This includes terms such as occurrence, contributing factor, other factor that increased risk, and safety issue. Publishing information Released in accordance with section 25 of the Transport Safety Investigation Act 2003 Published by: Australian Transport Safety Bureau © Commonwealth of Australia 2025  Ownership of intellectual property rights in this publication Unless otherwise noted, copyright (and any other intellectual property rights, if any) in this report publication is owned by the Commonwealth of Australia. Creative Commons licence With the exception of the Commonwealth Coat of Arms, ATSB logo, and photos and graphics in which a third party holds copyright, this report is licensed under a Creative Commons Attribution 4.0 International licence. The CC BY 4.0 licence enables you to distribute, remix, adapt, and build upon our material in any medium or format, so long as attribution is given to the Australian Transport Safety Bureau.  Copyright in material obtained from other agencies, private individuals or organisations, belongs to those agencies, individuals or organisations. Where you wish to use their material, you will need to contact them directly.

The occurrence

On 22 November 2024, at about 0828 local time, an Aérospatiale (Airbus Helicopters) AS332L1 Super Puma helicopter, registered N368EV, departed Broken Hill Airport, New South Wales for Albury with one pilot and a passenger on board. The flight was the final leg of a repositioning flight from Kuala Lumpur, Malaysia that started on 17 November 2024. The helicopter was being positioned at Albury for use as an aerial firefighting asset over the summer period.

At about 0955, while cruising at about 3,500 ft above mean sea level, the pilot noted a high frequency vibration through the airframe that was also apparent to the passenger. In response, the pilot lowered the collective control[1] and began a descent, noting that Hay aerodrome was about 22 NM (41 km) from their location. Recorded data showed the helicopter was descended at about 1,500 ft/min with an indicated airspeed of about 115 kt.

In interview with the ATSB, the pilot reported that, during the descent, they heard a loud thud, which was immediately followed by an uncommanded yaw[2] to the left. To control the yaw, the pilot established an autorotation[3] then indicated that they reduced the throttles to idle, however, inadvertently reduced the no 2 engine throttle beyond the idle gate position resulting in the engine shutting down. 

With the reduction in power, the uncommanded yaw ceased, and the pilot initiated a straight-in approach towards the open fields below. On approaching the ground, the pilot reported that, during the final flare with reduced airspeed, application of the collective control[4] to cushion the landing resulted in the helicopter yawing again. 

At about 0958, the helicopter landed heavily, initially impacting terrain in an upright attitude but facing in the opposite direction of flight, before rolling onto its right side. The emergency locator transmitter was activated in the impact and there was no post-impact fire. The pilot and passenger survived the impact but were seriously injured. The passenger, who was seated in the forward cabin, succumbed to their injuries. The helicopter was destroyed. 

Context

Pilot information

The pilot held a United States Department of Transportation - Federal Aviation Administration  Airline Transport Pilot Certificate (issued in 2023), with the necessary ratings to fly the helicopter. The pilot also held a Medical Certificate First Class, issued in November 2024.  The pilot also held an Australian-issued Commercial Pilot Licence (issued 2016) with an AS322 type rating.

The pilot completed AS332 type rating training in April 2023 and had about 8,000 hours total aeronautical experience at that time. Since completing the training, the pilot had logged about 400 hours flight time on the AS332. The pilot reported completing annual recurrent training on the AS332 in May 2024.

Helicopter information

General information

The AS332L1 Super Puma is a utility helicopter developed and initially produced by Aérospatiale, and subsequently manufactured by successor companies Eurocopter and Airbus Helicopters. N368EV was manufactured in 1988 by Aérospatiale with the serial number 2179. The helicopter was fitted with 2 Turbomeca Makila 1A1 turboshaft engines. 

The helicopter was registered in the United States and was issued a Certificate of Airworthiness by the Department of Transportation - Federal Aviation Administration in the transport category on 26 January 2011. The type certificate holder was Airbus Helicopters.

At the time of the accident, the helicopter had accrued about 28,323 hours total time in service. 

Tail rotor system

The AS332 tail rotor system comprises a 5-bladed tail rotor assembly that rotates in a counter‑clockwise direction. The tail rotor blades mount to the tail rotor hub and are driven by the tail gearbox via the inclined tail rotor shaft. 

Tail rotor blade pitch control occurs in response to the pilot’s tail rotor pedal inputs via mechanical connection to the servo control. The servo control actuates a pitch change control rod located within the hollow tail rotor shaft and is connected to the pitch change control plate. The pitch change control plate is mounted to and supported by a splined sleeve that slides laterally in a guide located within the tail rotor shaft (Figure 1 and Figure 2).

Figure 1: Tail rotor gearbox and related components

Source: Airbus Helicopters, annotated by the ATSB

Meteorological information

The Bureau of Meteorology’s forecast conditions for Broken Hill and Albury airports were described as CAVOK[5] for the duration of the flight. Recorded weather observations for Hay aerodrome showed the mean wind speed varying between 12 kt and 15 kt from the north around the time of the accident.  

The pilot reported that, following the departure from Broken Hill, and while cruising at about 3,500 ft, they were experiencing smooth flying conditions and had a tailwind of about 10⁠–⁠15 kt. 

Recorded data

The helicopter was not fitted with a cockpit voice recorder or flight data recorder. A recent modification included the installation of a helicopter usage and monitoring system from which preliminary flight data was extracted by the ATSB.            

The helicopter was also equipped with a Tracplus RockAIR portable tracking device. Additional navigational equipment was retained for further examination.

Wreckage and impact information

The helicopter impacted grass covered, flat terrain, in a slight left side down, but generally upright attitude facing about 320° (magnetic). The fuselage and belly sections were heavily compressed during the impact sequence, with the aft fuselage structure collapsing, resulting in the tail boom striking the ground. The tail boom ground strike then resulted in the vertical fin, with the tail gearbox and horizontal stabiliser attached, to separate from the tail boom. Following the ground contact and compression damage to the fuselage and tail boom, the helicopter rolled onto its right side. The wreckage was contained within the immediate area of the impact point and minimal forward projection of debris was noted. 

The landing gear was found in the down position with the nose and left main gear sustaining significant damage. The compression of the belly resulted in considerable release of fuel from the fuselage belly tanks. The cabin‑fitted ferry fuel tanks were dislodged from the floor mounts in the impact but remained intact.

During the impact sequence, fractures occurred on the main and tail rotor systems, including an associated loss of blade material consistent with a ground strike. However, each of the blades remained securely attached to their respective attachment point.

Examination of the wreckage found that the tail rotor pitch change control plate was detached from the tail rotor gearbox assembly and was the likely reason for the uncommanded yaw. Closer examination showed that the splined sleeve supporting the pitch change control plate had fractured at the mounting flange and the pitch change control rod was also fractured (Figure 2).

Figure 2: Tail rotor assembly with separation of pitch change control plate from gearbox

Source: ATSB

Component examination

Introduction

The fractured splined sleeve was examined at the ATSB’s technical facilities in Canberra, in the presence of representatives from the French Bureau d'Enquêtes et d'Analyses and Airbus Helicopters. 

The manufacturer advised that the splined sleeve had no safe life limit,[6] and its serviceability was determined by on-condition maintenance requirements. The continuation in service of the component was contingent on the absence of corrosion or surface scratches as determined by visual inspection at specified intervals. 

Component examination 

Following the removal of its surface protective coating, the splined sleeve was identified as part number AS332A33 0070.20. The sleeve’s serial number was also identified to assist with determining the component manufacturing history. 

Initial examinations of the fracture surface found that a fatigue crack had propagated around the majority of the splined sleeve’s circumference, leading to fracture of the sleeve in the section adjacent to the pitch change control plate mount flange. Further examination is to be conducted to determine the crack origin and identify the factors contributing to the cracking (Figure 3).

Figure 3: Separation of the pitch change control plate mount flange from the splined sleeve

Source: ATSB

Safety action

In response to this accident, Airbus Helicopters published safety related information, which included:

• Safety Information Notice 4082-S-64 on 29 November 2024 that highlighted tail rotor assembly maintenance tasks, specific to inspection and lubrication requirements.
• Alert Service Bulletin ASB AS332-64-20-003 on 23 December 2024 that specified an inspection for defects of the splined sleeve radius area of the control plate mount flange.

Further investigation

To date, the ATSB has:

• examined the wreckage
• collected items of evidence from the accident site
• collected pilot and aircraft records
• conducted interviews with relevant parties
• liaised with Airbus Helicopters and the French Bureau d'Enquêtes et d'Analyses 
• conducted a preliminary examination of the splined sleeve.

The investigation is continuing and will include:

• a further review and detailed examination of the splined sleeve
• examination of the tail gearbox and components
• an assessment of accident survivability aspects
• a review of helicopter records and loading aspects 
• a review of the pilot’s qualifications and experience
• analysis of recorded data.

A final report will be released at the conclusion of the investigation. Should a critical safety issue be identified during the course of the investigation, the ATSB will immediately notify relevant parties so appropriate and timely safety action can be taken. 

Purpose of safety investigations The objective of a safety investigation is to enhance transport safety. This is done through:  identifying safety issues and facilitating safety action to address those issues providing information about occurrences and their associated safety factors to facilitate learning within the transport industry. It is not a function of the ATSB to apportion blame or provide a means for determining liability. At the same time, an investigation report must include factual material of sufficient weight to support the analysis and findings. At all times the ATSB endeavours to balance the use of material that could imply adverse comment with the need to properly explain what happened, and why, in a fair and unbiased manner. The ATSB does not investigate for the purpose of taking administrative, regulatory or criminal action. Terminology An explanation of terminology used in ATSB investigation reports is available here. This includes terms such as occurrence, contributing factor, other factor that increased risk, and safety issue. Publishing information Released in accordance with section 25 of the Transport Safety Investigation Act 2003 Published by: Australian Transport Safety Bureau © Commonwealth of Australia 2025 Ownership of intellectual property rights in this publication Unless otherwise noted, copyright (and any other intellectual property rights, if any) in this report publication is owned by the Commonwealth of Australia. Creative Commons licence With the exception of the Commonwealth Coat of Arms, ATSB logo, and photos and graphics in which a third party holds copyright, this report is licensed under a Creative Commons Attribution 4.0 International licence. The CC BY 4.0 licence enables you to distribute, remix, adapt, and build upon our material in any medium or format, so long as attribution is given to the Australian Transport Safety Bureau.  Copyright in material obtained from other agencies, private individuals or organisations, belongs to those agencies, individuals or organisations. Where you wish to use their material, you will need to contact them directly.

[1]     Collective: a primary helicopter flight control that simultaneously affects the pitch of all blades of a lifting rotor. Collective input is the main control for vertical velocity. Raising or lowering the collective also increases or decreases engine power to maintain rotor RPM as the rotor drag changes.

[2]     Yawing: the motion of an aircraft about its vertical or normal axis.

[3]     Autorotation: Autorotation is a condition of descending flight where, following engine failure or deliberate disengagement, the rotor blades are driven solely by aerodynamic forces resulting from rate of descent airflow through the rotor. The rate of descent determined mainly by airspeed.

[5]     Ceiling and visibility okay (CAVOK): visibility, cloud and present weather are better than prescribed conditions. For an aerodrome weather report, those conditions are visibility 10 km or more, no significant cloud below 5,000 ft, no cumulonimbus cloud and no significant weather.

[6]     Safe life limit: An airworthiness limitation that is applied to life limited parts, which have a predetermined lifespan after which they must be replaced to ensure safety.

Investigation summary

What happened

On 16 November 2024, an amateur-built experimental certificate Morgan Cougar Mk 1 aircraft, registered VH-LDV, with a pilot and 2 passengers on board, departed from West Sale Airport, Victoria for a local area flight. The aircraft collided with terrain in a paddock it was orbiting around, about 19 km north-north-west of West Sale Airport, 17 minutes after departure. The aircraft was destroyed, and the 3 occupants were fatally injured.

The pilot was operating a VH-registered aircraft with a Recreational Pilot Licence (RPL), issued by CASA in recognition of the pilot holding a Recreational Pilot Certificate (RPC), issued by Recreational Aviation Australia (RAAus). 

What the ATSB found

The aircraft entered an accelerated aerodynamic stall while in a steep turn at a low speed and height from which it was too low to recover (about 220 ft above ground level). The pilot had a reported history of conducting steep turns at low heights, and on occasions at low speeds, and had low flying hours in the aircraft and no transition training. Therefore, it was likely that the pilot was not aware of the stall characteristics of the aircraft and that it might depart controlled flight in an abrupt and unexpected manner. 

The pilot’s history also included several counselling sessions they had received from members of the local aviation community in response to risky flying activities. However, no official reports were submitted to authorities and therefore no follow-up action was ever initiated.

A review of the pilot’s examination history revealed several errors about aerodynamic stalling in exams conducted during 2024 and it was concluded that the pilot likely had inadequate knowledge of the relationship between angle of bank, load factor and stall speed. Additionally, the investigation found several instances of irregular practices in training and exams at the Adventure Flight Training (AFT) school, which included the pilot’s exams, and concluded that those management practices likely contributed to the pilot’s inadequate knowledge.

RAAus administered the examination system, and it was found to have inadequate controls to mitigate the practices at AFT. When RAAus uncovered the problems at AFT in 2024, they issued a safety related suspension (SRS) notice against the chief flying instructor of AFT, which resulted in the cessation of operations in August 2024. 

After the accident, RAAus issued another SRS against the AFT graduates for potential knowledge deficiencies. However, when CASA were advised of this action, they did not follow-up to verify if any of those graduates also held a CASA licence granted based on holding an RAAus RPC which had been suspended. It was subsequently found that 2 members held a CASA-issued licence, granted based on their suspended RPCs.

Furthermore, the accident aircraft was found to have design deficiencies, which contributed to the severity of the occupants’ injuries. They included a lack of energy attenuation in the landing gear and seating, and the installation of a fuel tank between the engine and instrument panel that ruptured and caused the post-crash fire. In addition, it was likely that car seatbelts were fitted and the front seatbelts failed in the accident, which resulted in the front seat occupants being ejected from their seats. 

Finally, it was found that the CASA advisory circular for amateur-built experimental certificate aircraft provided recommendations to address some aspects of aircraft crashworthiness, which included seatbelts. However, it did not address energy attenuation or fuel tank installation. In addition, while it provided safety recommendations for pilots conducting flight testing, it did not recommend transition training for new owners of these aircraft.   

What has been done as a result

RAAus commenced a digital systems redevelopment project with scoping of user requirements completed in 2023, which includes their learning management system. This incorporates the implementation of an online exam system. RAAus are also progressing the re-drafting of several key documents in their Exposition, which includes updates to the following:

• flight operations manual to contain greater clarity around the conduct of RAAus examinations
• occurrence and complaints handling manual to include a description of the process for handling a safety related suspension for an individual if their membership has lapsed
• syllabus of flight training to include further development of the stalling element of the syllabus. 

CASA has implemented a more robust process to ensure that all reports received that relate to suspension, variation or cancellation of authorisations issued by an approved self‑administering organisation will include a review of CASA records to determine if the reported individual also holds a ‘same-in-substance’ CASA-issued authorisation. If so, the holder’s qualifications will be subject to review through the CASA Coordinated Enforcement Process.  

Safety message

The investigation revealed a trend in risky flying behaviour by the accident pilot, which was likely compounded by inadequate knowledge from a flight training school that had developed irregular practices in the delivery of training and had inadequate supervision. While many people knew of the pilot’s risky flying behaviour and had attempted to counsel them, there was no evidence that any of the incidents were reported to authorities, and the counselling efforts were ultimately unsuccessful. 

The ATSB has previously advocated for witnesses, particularly those within the aviation industry, to report any concerns regarding unsafe behaviours through mechanisms such as confidential reporting systems (see AO-2019-027). The ATSB re-iterates this previous safety message.

CASA has published recommended guidance for amateur-built experimental certificate aircraft. While this publication is directed at those who design, build and flight test these aircraft, the safety precautions should be read by new owners and considered equally applicable to them.

The ATSB SafetyWatch highlights the broad safety concerns that come out of our investigation findings and from the occurrence data reported to us by industry. One of the safety concerns is reducing the severity of injuries in accidents involving small aircraft. In this accident the lack of energy attenuation and location of the fuel tank in the design of the aircraft and the likely fitment of car seatbelts all increased the risk to occupants in the event of a ground collision. 

Summary video

The occurrence

At 1730 local time on 16 November 2024, an amateur-built Morgan Cougar Mk 1 aircraft, registered VH-LDV, with a pilot and 2 passengers on board, departed from West Sale Airport, Victoria for a local area flight. The pilot was seated in the front left seat, and the passengers were seated in the front and rear right seats. A review of Airservices Australia automatic dependent surveillance-broadcast (ADS-B) data identified that the aircraft conducted a left turn on departure and tracked 15 km north of West Sale Airport to the town of Maffra, where they arrived overhead at about 1736 (Figure 1).

Figure 1: Accident flightpath with key timings and locations

Sources: Airservices Australia and Google Earth, annotated by the ATSB

The aircraft made a series of turns overhead the town of Maffra for about 4 minutes. At 1740, the aircraft departed from overhead Maffra and tracked about 11 km west towards Tinamba West. The aircraft conducted a right-hand turn overhead a property at Tinamba West, which belonged to relatives of the aircraft occupants, before commencing a series of left-hand turns (orbits) around a point about 1 km to the south-east of the property over open paddocks (Figure 2). 

On the second orbit, the aircraft made a low pass along the Macalister River, adjacent to where several witnesses, which included 2 adults, were located. The 2 adults later stated that they had witnessed the aircraft conduct 2 orbits past their location before the accident. They reported the second pass along the river was lower than the first, such that they could both see the occupant in the rear seat, and that the aircraft sounded normal.

Figure 2: Orbits and the location of witnesses

Sources: Airservices Australia and Google Earth, annotated by the ATSB

A closed-circuit television (CCTV) camera, located about 700 m north-north-east of the accident site, captured the aircraft entering a left turn towards the camera on its third orbit (Figure 3 [1]). During the turn the angle of bank increased to a steep turn attitude (Figure 3 [2]) before the nose of the aircraft pitched down and the aircraft descended in the left turn behind trees (Figure 3 [3]). 

Figure 3: CCTV footage of final turn

Images subject to visual distortion (fisheye lens effect). Source: Victoria Police, annotated by the ATSB

One of the witnesses reported that, as the aircraft approached them for a third pass, it did a hard left turn and then appeared to be falling and not gliding towards the ground, as though it did not have enough speed. They reported that the wings levelled after the turn and it landed very hard on its belly and immediately caught fire. The second witness saw it bank hard left and fall out of the sky but did not see the collision. The 3 occupants were fatally injured, and the aircraft was destroyed.

Context

Accident site and wreckage

Overview

The aircraft impacted flat and open terrain at an elevation of about 130 ft and produced a ground scar on a track of 315° T (Figure 4). The length of the wreckage trail was 30.3 m from the first ground scar to the propeller spinner, with the fuselage resting on a heading of 303° T. Impact analysis indicated the aircraft struck the ground in a slight left wing low and close to level pitch attitude, which was consistent with the witness report of the collision.

Figure 4: Accident site

Source: ATSB

There was a delta-shaped fuel spray and debris pattern along the wreckage trail. A fuel‑fed fire occurred after the ground impact, however, most of the fire damage to the aircraft was confined to the fuselage within the area bounded by the firewall,[1] aft bulkhead (behind rear seats) and the inboard sections of the wings (Figure 5). The engine and propeller were also affected by the post‑impact fire, but to a lesser extent than the fuselage. The wings and tailplane (except the rudder) remained attached to the fuselage. The rudder was found in the wreckage trail. 

Figure 5: Fire damage to the aircraft

Source: ATSB

The engine remained attached to the firewall, which had separated from the fuselage, and the 3-bladed propeller hub was attached to the engine. There was considerable disruption between the engine and airframe. One substantially fire-damaged carbon fibre propeller blade was attached to the hub and the other 2 propeller blades, which were not fire‑affected, had separated at their roots and were found fragmented within the debris field.

Aircraft inspection

Engine and propeller

The 2 witnesses to the accident sequence provided different accounts of the noise of the aircraft just prior to the collision. One reported that the aircraft sounded normal before the final turn and then went quiet, whereas the other witness reported no change in the sound of the aircraft during the accident sequence. 

The intake manifolds, carburettors, drive belts, oil hoses, and fuel lines were heavily damaged by the post-impact fire. The left carburettor was damaged beyond assessment, and the right carburettor was found with the throttle valve in the idle position. However, the carburettor throttle valve is spring loaded to idle, so the as-found position was not considered a reliable indicator of its position in flight.

The number 1 cylinder head was removed for inspection and was found to be lubricated and did not exhibit any signs of distress. The other cylinders could not be accessed due to impact damage. The engine oil filter and oil sump magnetic plug were inspected, and no metallic debris was identified.

The turbocharger compressor scroll was found separated from the turbocharger and directly below the turbocharger assembly. The scroll exhibited an overstress failure, with fracture surfaces but no scoring. Several turbocharger compressor vanes exhibited bending in the opposite direction of rotation, which indicated the compressor was running at impact (Figure 6).

Figure 6: Rearward bending of turbocharger compressor vanes

Source: ATSB

The propeller hub was secured to the engine output flange by 6 bolts and concentric locating pins. The hub was removed for inspection and very slight ovalisation of all 6 of the locating pins’ hub-side holes in the direction of rotation was noted. 

Two of the propeller blades fractured at the blade root and separated from the hub, leaving the propeller root sections still clamped in the hub. The carbon fibre remnants on the root sections indicated tearing and separation of the blades in the opposite direction to rotation. 

One of the propeller blade root hubs was relatively unbent and the following blade root hub (in the direction of rotation) exhibited rearward bending. This suggested a loss of propeller energy between consecutive blade ground strikes and the possibility that the first blade to separate was being driven by engine power.

The use of non-metallic propeller blades increased the uncertainty in the engine power assessment. However, in combination with the turbocharger compressor damage it was concluded that the engine was operating at impact, but the power level could not be determined. 

Flight controls

Primary aircraft flight controls were of the direct acting cable, pushrod, and bellcrank type with a dual yoke control installed for elevator and aileron control. The wing flaps were electrically powered and found in the retracted position. The flaps could not be tested due to damage.

Rudder, elevator, and aileron controls were free to move about their full range. Several control cables were found severed and were inspected for signs of pre-impact failure. No wear, bird-caging, fretting, or other indications of damage were noted on the cables, and it was concluded that all these cables failed from overstress during the ground collision.

The rudder separated from the vertical stabiliser and was found in the wreckage trail. The mounting hardware was found, and the fracture surfaces of the flight control attachment points were consistent with an overstress failure.

While ATSB investigators were handling the yoke controls for inspection and photography, the chainring, which was part of the aileron control, separated under gravity from its bearings and support frame (Figure 7). However, given that they were not found separated, and that the aircraft attitude was recovered towards wings-level before the collision, it was concluded that the controls did not separate in-flight. The chainring and bearings were retained for further examination at the ATSB technical facility and details of that examination are provided in Appendix A – Examination of the flight controls.

Figure 7: Chainring separation from bearings and support frame

Source: ATSB

Fuel system

The aircraft fuel system consisted of a 55 L fiberglass tank in each wing, located aft of the main spar, and a 90 L fibreglass main tank between the instrument panel and the firewall. Fuel could be transferred from the wing tanks to the main tank via an electric transfer pump. The engine feed was from the main tank, via a fuel filter and 1 of 2 electric pumps.

The wing fuel tanks were found empty and relatively undamaged. The main tank was completely consumed by the impact and fire, along with significant parts of the surrounding fuselage. This was consistent with the flight fuel carried in the main tank.

Undercarriage

The undercarriage was a fixed tricycle gear, with a single-piece fibreglass strut supporting both main wheels, and a castering, spring lever nose wheel. The main and nose gear were found in the wreckage trail and their separation from the airframe was consistent with multiple overstress failures of the attachments at impact. The main gear assembly exhibited no evidence of permanent deformation or absorption of energy. 

Seats and restraints

The aircraft was designed and built with 2 front seats and a 2-place rear bench-seat arrangement. The front seats were found in the wreckage, and their rear mountings were attached to the fuselage seat frame aluminium angle cross-member. The steel bolts used to mount the rear of the seats to the aluminium angle were present and fastened. The forward steel cross-member for the front seats was bowed forward (Figure 8). The right seat pan was retained by the seat back and appeared to have collapsed onto the main wing spar,[2] located underneath the front seats. The left front seat pan had separated from its seat back and was found in front of the seat frame forward cross-member.

Figure 8: Aircraft seat frame, wing spar and seats

Source: ATSB

Both front seatbelt latch plates were found separated from their buckles and their associated harnesses were destroyed by the fire (Figure 9). The rear seats and seatbelts were destroyed by the post‑impact fire. However, the seatbelt latch plate for the rear seat occupant was found in its buckle.

Figure 9: Aircraft seatbelt latch plates

Source: ATSB

Instruments and avionics

The aircraft was fitted with:

• a Dynon Skyview SV-D1000 avionics unit, which provided a primary flight display with a navigation display and engine instruments display
• a 2-channel autopilot system
• analogue airspeed, oil pressure, altimeter, turn/slip and vertical speed instruments.

The instrument panel and instruments were found together in the wreckage, forward of the front seats and behind the engine firewall. All instruments and the panel were destroyed by the impact and fire. However, the Dynon unit was retained by the ATSB for examination (see the section titled Flight path analysis).

Meteorological information

The Bureau of Meteorology provided 30-minute METAR[3] recordings for the East Sale Airport, located about 30 km south-east of the accident site. At 1730, the temperature was 26°C and the wind was 17 kt from 090° T. The visibility was greater than 10 km and no cloud was detected. Similar conditions were recorded at 1800. A local weather station about 4 km north of the accident site recorded the weather data at 5-minute intervals. Table 1 presents the temperature, mean wind and wind gust data recorded at 1745 and 1750 by the local weather station.

Table 1: Local weather station recordings

Flight path analysis

The aircraft was fitted with a Dynon Skyview SV-D1000 avionics unit, with the capability to record various flight path parameters. The unit was recovered from the accident site and examined at the ATSB facilities. The memory chip was recovered from the internal memory unit and read. However, due to the extensive thermal exposure beyond the specifications of the chip, the data was corrupted and not usable.

Airservices Australia ADS-B data was obtained for the flight path analysis. The data included altitude in 25 ft increments and groundspeed with timings, which were combined with the CCTV camera footage for flight path analysis. A mean wind speed of 6 kt and wind gust speed of 12.8 kt from 124° T were used to calculate a range of estimated calibrated airspeeds (CAS) for each data point.

A trend over the last 3 minutes was noted with the aircraft generally descending from a recorded altitude of 850 ft above mean sea level (AMSL) to 275 ft AMSL, with a low pass at 97 ft above ground level (AGL) during the second left orbit overhead the Macalister River. The groundspeed varied over the last 3 minutes from 103 kt to 71 kt, with a gradual and almost continuous reduction in speed below that recorded during the previous orbit speeds over the last 30 seconds of the flight.

The final turn started at 1746:52 at 64 kt (67–74 kt CAS) and 269 ft AGL. The nose drop observed in the CCTV footage during the final turn, followed by a rapid descent, was indicative of an aerodynamic stall[4] in a steep turn. The stall likely occurred at 1746:59 at 56 kt (59–65 kt CAS) and 221 ft AGL. After the stall there was an abrupt reduction in altitude and increase in speed, consistent with initiation of a stall recovery (Figure 10).

Figure 10: Plot of ADS-B data and CAS calculations

Source: ATSB

The final turn was of a tighter radius than the previous orbits and analysis of the radius of this turn indicated it was consistent with a turn to align with the Macalister River and would have required an average angle of bank of 45° in a steady coordinated turn. The turn radius appeared to reduce during the turn at a relatively constant speed, which would have required an increase in the angle of bank and load factor. For about the last minute of flight, the aircraft was operating below a height of 500 ft, which was the minimum height applicable to this portion of the flight, as prescribed in Civil Aviation Safety Regulation (CASR) 91.267. Further description of each orbit is provided in Appendix B – Flight path description.

Aircraft information

General information

The aircraft was an amateur-built Morgan Cougar Mk 1, registered VH-LDV, issued with a special certificate of airworthiness under the designation: experimental certificate. It was a 4-seat, piston-engine aircraft with a maximum take-off weight of 800 kg. The aircraft was fitted with a Rotax 912 ULS 4-cylinder turbocharged engine and 3-bladed composite (carbon fibre) propeller. The aircraft’s builder sold it to a syndicate of 3 pilots, which included the accident pilot, on 5 November 2024, with its manufacture date recorded as 2013 and with 136.9 airframe hours.

The aircraft build started in May 2013 and the experimental certificate for Phase 1 flight testing was issued by a Civil Aviation Safety Authority (CASA) delegate in December 2015. The experimental certificate for Phase 2, completion of the test flying phase, was issued by the same CASA delegate in April 2017. 

Amateur-built experimental aircraft

According to the CASA advisory circular (AC) 21-10 v4.3: Experimental certificates, an experimental certificate may be issued for the purpose of operating amateur-built aircraft, and it does not attest to the airworthiness of the aircraft. CASA AC 21.4(2): Amateur-built experimental aircraft – certification (published in 2000) stated:

An amateur-built aircraft is an aircraft, the major portion of which has been fabricated and assembled by a person or persons who undertook the construction project solely for their own education or recreation. 

Amateur builders should call upon persons having experience with aircraft construction techniques…to inspect particular components…prior to closure and to conduct other inspections as necessary.

The AC required an authorised person, or CASA, to only inspect the aircraft once prior to the initial test flight and the inspection should establish that:

• the aircraft is registered and marked in accordance with the requirements

• the aircraft meets the major portion rule

• the weight and balance data is available and the aircraft has been correctly weighed

• the engine(s) and flight controls operate properly

• the pitot static system and associated instruments operate properly.

• Note: The person carrying out the inspection is not responsible for the integrity of the design or construction of the amateur-built experimental aircraft, nor for the identification of any structural design or construction deficiencies — responsibility for the design, construction and integrity of the aircraft rests with the amateur builder. 

In accordance with CASA AC 21.4(2), the builder maintained a build-log that detailed the progressive build of the aircraft with photographs and notes. The builder consulted with the designer during the initial build and with both the designer and the CASA delegate for subsequent modifications. The designer of the aircraft was deceased prior to the accident. 

Weight and balance

The maximum take-off weight published in the aircraft logbook was 800 kg and the centre of gravity limits were between 2,263 mm and 2,537 mm aft of the datum. The aircraft was reweighed 2 days prior to the accident, which involved transferring all fuel remaining in the wing tanks into the main tank. The transfer process resulted in empty wing tanks and a full main tank.

The weight and balance for start-up and at the time of the accident were calculated and found to be within the published limits. 

Builder modifications to the design

The aircraft builder reported to the ATSB that they made several modifications to the original design, consulting with the CASA delegate and designer about the changes. They reported that under the original design, aileron and elevator control was via a stick, with a linear relationship between stick and control surface movement across the full range. However, the stick control required large inputs for small movements of the control surfaces, felt sloppy and was designed with components bolted to the floor in a manner that exposed them to interference from the occupants. 

After a taxiing accident in 2019, the builder incorporated modifications, which included a new engine (Rotax) and propeller, yoke controls and roller bearings to eliminate lateral movement (play) in the horizontal stabilator control tube. The builder noted improved climb and cruise performance after the modifications, but reported the greatest improvement was in flight handling. 

Following the modifications, the roll, pitch and yaw motions were described as ‘smooth, linear and predictable… There was no slop in the control system and this resulted in the aircraft being responsive without being twitchy.’ The autopilot actuators provided additional resistance and a heavier feel to the original design. The builder reported no noticeable changes to the stall speed or aircraft reaction during a stall after these modifications but recovery from a stall was reported to be quicker than previous. 

Aircraft stall warning and characteristics

Stall warning

While not published in the pilot operating handbook (POH), the aircraft was fitted with a stall warning system incorporated into the Dynon avionics unit. The documentation for the unit stated that it provided an audio alert as the angle of attack increased, which started as an intermittent tone and increased in frequency as the angle of attack increased, until it became a continuous tone at the critical angle of attack.[5]

There were 3 options in the settings for how early the intermittent tone activated. The ATSB could not determine what was set or if a calibration flight was conducted. The builder reported that they believed it was factory set and one of the new owners reported they believed there was an angle of attack indicator but no audible stall warning. They further stated that they had not conducted any of their own verification/calibration flights before the accident.

Stall characteristics

The stall characteristics were described in the POH as having about a 10 kt buffet warning before a slow nose drop at the stall until flying speed was regained. The POH’s published ‘straight and level’ clean indicated stall speed was 37 kt. However, after construction, the aircraft was subject to 40 hours of restricted flying operations under Phase 1 of its experimental certificate, which included stall testing. The results from Phase 1 testing were recorded in the aircraft logbook, which indicated the stall speed was found to be 38 kt. 

The builder described the aircraft handling characteristics approaching the straight and level clean stall as ‘a mush’ with no sudden nose‑down pitching moment. However, they reported that during a 30° angle of bank left turn, the aircraft started to stall at about 42 kt and then suddenly pitched nose-down with a left yaw. The aircraft was quickly recovered but the builder was reportedly surprised by the different response to a stall in a turn to what was experienced in straight and level flight and hypothesised that a greater angle of bank might exacerbate the response.

The following table presents the indicated stall speeds and load factors in level coordinated turns from wings level to 75° angle of bank and up to a load factor[6] of 3.86, noting the published manoeuvring limit for the aircraft was 4G. The manoeuvring stall speed was calculated by multiplying the 1G stall speed by the square root of the load factor.

Table 2: Calculated stall speeds for increasing angle of bank and load factor

The builder recalled discussing various types of stalls, including accelerated stalls, with the aircraft designer. However, the designer recommended against the builder testing these characteristics unless accompanied by either the designer or an experienced instructor. The builder did not conduct any stall testing additional to that detailed above.

Stall testing for amateur-built aircraft

In AC 21.4(2), CASA ‘strongly urged’ builders to ‘make detailed reference to the U.S. FAA [Federal Aviation Administration] Advisory Circular AC 90-89, “Amateur-Built Aircraft Flight Testing Handbook”, prior to their flight programs commencing, and follow the guidance provided.’ In accordance with the FAA AC, for straight and level stall testing, the aircraft should be slowed towards the expected stall speed at 1 kt per second and the stall warning should occur about 5 kt before the stall. 

The FAA AC stated that a sharp wing drop during stall testing could be regarded as the onset of spin autorotation, and the recommended corrective action is reducing power, full opposite rudder, and lowering the nose to the horizon or below. The guidance for flight testing of accelerated stalls provided the following description:

An accelerated stall is not a stall reached after a rapid deceleration. It is an in-flight stall at more than 1 G, similar to what is experienced in a steep turn or a pull up.

The accelerated stall is based on a closure rate between the aircraft speed and stall speed. Standards for type certified aircraft have historically[7] used a closure rate of 3‍–‍5 kt per second for testing accelerated stall characteristics or required a minimum load factor for the test conditions (Gratton, 2015). 

A turning manoeuvre is often used for the accelerated stall testing, which can affect the aircraft response. According to Gratton (2015), low wing aircraft tend to roll into the turn during a turning stall and high wing aircraft tend to roll out of the turn. Consequently, certification authorities have historically placed roll limits on the acceptable response of an aircraft during a turning or accelerated stall (Gratton, 2015). Therefore, accelerated stall flight testing may not be recommended for an amateur-built aircraft and the notes within the accelerated stall section of the FAA AC contained the following advice:

Do not attempt this or any other extreme maneuver unless the designer or kit manufacturer has performed similar tests on a prototype aircraft identical to the amateur-builder’s aircraft.

Of note, the reference from Gratton (2015) that low wing aircraft tend to roll into the turn during a turning stall, will, in combination with a nose down pitch, produce a nose low unusual attitude to the pilot. While the correct recovery technique from a conventional stall is to apply power as soon as the wings are unstalled, the standard recovery technique from a nose low unusual attitude is to close the throttle, roll wings level and then pull up (CASA, 2007).

Transition training

Purchase of the aircraft

The builder sold the aircraft due to medical issues that made it difficult for them to inspect and operate the aircraft and inhibited their ability to egress from the aircraft in an emergency. Consequently, the builder did not accompany any potential buyers on their trial flights. The inspections and trial flights of the aircraft occurred at Whyalla Airport, South Australia, and the syndicate that purchased the aircraft were the second interested buyers.

The builder reported that the first interested buyer had about 800 hours experience on slower aircraft, which included experimental kit-built aircraft. The buyer conducted a trial flight accompanied by a more experienced pilot who advised them against the purchase due to the performance difference from their previous aircraft. The accompanying pilot reported to the builder that the buyer was used to flying 80 kt aircraft, not 130 kt aircraft.

The syndicate that purchased the aircraft consisted of a recreational pilot certificate (RPC) holder and 2 Recreational Aviation Australia (RAAus) instructors. The instructors each held a CASA-issued recreational pilot licence (RPL) with navigation endorsement, and one of them was the accident pilot. They arrived together at Whyalla Airport in another light aircraft as the second prospective buyers. 

The syndicate conducted several trial flights at Whyalla, and the builder briefed them on the aircraft logbook and the POH but could not recall the specific details of what was covered. The builder believed the syndicate members were going to study the POH the night before their departure from Whyalla and the builder made themselves available the following day to answer any questions but could not recall if any were asked. The syndicate members signed the sale agreement on 5 November 2024 and departed from Whyalla with the aircraft on 6 November. 

The builder had no recollection of discussing the aircraft’s banked stall characteristics with them and had never received such a brief themselves in the past when introduced to a new aircraft. They did not advise the syndicate to seek transition training or recommend aerial work exercises as part of their familiarisation process. The builder was aware that 2 of the syndicate members held instructor qualifications with RAAus in addition to CASA licences. Therefore, the builder (who was not an instructor themself) did not think it was necessary to advise them about flight training matters.

One of the syndicate members was concerned about the aircraft’s centre of gravity with rear seat passengers and they agreed to have it reweighed before conducting any of their own verification flights. This was done at West Sale Airport on 14 November 2024, and no significant changes were recorded by the weight and balance organisation.

As the aircraft was in the single-engine class rating of less than 1,500 kg, the syndicate’s RPL-qualified pilots were able to fly the aircraft without additional flying training or qualifications. The ADS-B data history for the aircraft revealed about 7.7 hours were flown by the syndicate from 4 November 2024 until the accident flight, which included 4.5 hours of ferry flights from Whyalla to Moama, New South Wales, and from Moama to West Sale. There were also several check flights associated with rectifying a blocked fuel strainer. While the accident pilot had received dual transition training for other aircraft, which included the Bristell and Pitts Special, this was not undertaken on the accident aircraft.

One of the syndicate members reported that they didn’t think the pilot had the opportunity to do any aerial work exercises in the aircraft before the accident and they suspected that the pilot may not have appreciated the heavier aircraft, in which they had low flying hours. The other syndicate member reported that the pilot had limited flying experience in the aircraft and suspected that the pilot did not understand the risks of what they were doing with respect to steep turns, load factor and the associated effect on stall speed.

CASA flight testing and training advice

CASA AC 21.4(2) included recommended safety precautions for the flight-testing phase, emphasising that:

• a graduated process of familiarisation should be followed, starting with the ground handling characteristics of the aircraft before attempting flight operations
• emergency equipment and personnel should be available before the first flight
• ‘Violent or aerobatic manoeuvres should not be attempted until sufficient flight experience has been gained to establish that the aircraft is satisfactorily controllable throughout its normal range of speeds and manoeuvres.’

The minimum qualifications required for the Phase 1 flight testing was a CASA-issued private pilot licence (PPL) with the appropriate endorsements.

CASA AC 21.4(2) also stated that ‘Flight training will be permitted under certain circumstances, i.e. type endorsement training and training given in the aircraft to its owner.’ A separate section addressed the maintenance aspects for new owners, which prohibited them from certifying for maintenance, and that it must be certified by a Licenced Aircraft Maintenance Engineer (LAME) when no longer owned by the builder. However, there was no recommendation for new owners to seek transition training or for designers or builders to recommend buyers conduct transition training.

ATSB aviation research investigation

The ATSB aviation research report 

Amateur-built aircraft Part 2: Analysis of accidents involving VH-registered non-factory-built aeroplanes 1988-2010, was published in 2013. It included findings related to the accident and injury rates (with implications for the crashworthiness of these aircraft) and the experience of pilots involved in these accidents, as follows:

Amateur-built aircraft had an accident rate three times higher than comparable factory-built certified aircraft conducting similar flight operations between 1988 and 2010. The fatal and serious injury accident rate was over five times higher in amateur-built aircraft, in particular due to relatively more serious injury accidents. 

The pilots of amateur-built aircraft involved in accidents were significantly more experienced overall than factory-built aircraft accident pilots. However, they were significantly less experienced on the aircraft type that they were flying at the time of the accident.

A quarter of accidents were from loss of aircraft control.

The safety action section of the report included initiatives from the Sport Aircraft Association of Australia (SAAA), as follows:

Working with the Civil Aviation Safety Authority (CASA) to provide a legal framework for better training in amateur-built aircraft.

Working with CASA to allow a legal framework for suitably qualified pilots to give instruction in amateur-built aircraft both for the aeroplane flight review (AFR) and transition training for pilots (post-phase one).

The SAAA subsequently produced a Flight Training and Safety Manual supported by their Flight Safety Advisor program. However, a pilot operating an experimental aircraft needed to be a member of SAAA to access these resources.

Federal Aviation Administration advisory circular

In 2012, the United States National Transportation Safety Board published a safety study on The Safety of Experimental Amateur-Built Aircraft (NTSB/SS-12/01). Their study found that pilots who did not seek training were over‑represented in accidents, and that accidents involving loss of control could be reduced with transition training. This led to a recommendation for the FAA to develop resources for transition training and encourage builders and new owners to complete the training.

In 2015, the FAA published AC 90-109(A) Transition to unfamiliar aircraft. The purpose of the FAA AC was ‘to help plan the transition to any unfamiliar fixed-wing airplanes, including type-certificated (TC) and/or experimental airplanes.’ The AC stated that ‘accidents resulting from loss of aircraft control or situational awareness frequently result from pilot unpreparedness for challenges presented by the aircraft’ and provided recommendations for training experience based on aircraft performance and handling characteristics. It contained an extensive section on stall characteristics, which included the following points:

There are no rules for stall behavior with experimental airplanes.

Some experimental airplanes can be flown in a carefree manner with the stick all the way back, while others can depart controlled flight dramatically without any perceptible warning.

Since amateur-built airplanes are built by individuals, there can be a wide variation in the stall behavior of identical models.

Receive training in your airplane on stall avoidance and recovery from a qualified instructor, preferably with recent experience in the make and model.

Periodically practice stall avoidance, entry, and recovery at a safe altitude after you have received enough instruction to feel comfortable. Stall recognition and recovery should not be self-taught. Your first experience should not come from an inadvertent stall that catches you by surprise.

The appendices of the FAA AC provided a list of families of aircraft, based on their characteristics, with examples of experimental aircraft within each family. The accident aircraft was described to the ATSB as being responsive by the builder and very responsive by one of the syndicate members. Appendix 3 of the FAA AC was for aircraft with rapid flight control response, and it included the following information:

There are many more experimental airplanes that may look more like type-certificated (TC) airplanes, but they actually have light control forces and/or very quick maneuvering response. The hazard of light forces and rapid response is that without some level of training, the pilot may over-control the airplane.

Best Training. The best training is accomplished in the specific airplane the pilot intends to fly with a well-qualified instructor who has recent experience in the specific make and model.

In this case, the accident pilot had conducted transition training on the Pitts Special aircraft with an instructor who also had experience with the Morgan Cougar Mk 1 aircraft, though not the accident aircraft. The instructor’s experience with the Morgan Cougar included flying them and modifying them to improve their handling qualities. This offered the accident pilot an opportunity to undertake transition training for the Morgan Cougar Mk 1 that would have been consistent with the ‘best training’ model recommended in FAA AC 90-109(A).

Crashworthiness and survivability

Occupant positions and injuries

The seating configuration during the flight was the pilot in the front left seat, a passenger in the front right seat and a second passenger in the rear right seat. A full autopsy was conducted on the pilot, and a computed tomography scan and external examination was conducted on the 2 passengers at the Victorian Institute of Forensic Medicine. Toxicology analysis of blood was conducted for all occupants.

The examinations for all occupants revealed extensive non-survivable blunt force trauma injuries to the head, chest and lumbar spine. Examination of the pilot indicated that they were deceased prior to the fire. Toxicology results found no ethanol, common drugs or poisons, and carboxyhaemoglobin (an indicator of carbon monoxide exposure) was not detected.

CREEP methodology

The CREEP methodology used for analysing the crashworthiness and survivability of aircraft accidents is based on:

• Container – maintain a liveable volume
• Restraint – retain the occupants in their seats and the seats to the airframe
• Energy attenuation – minimise the transmission of forces to the occupants
• Environment (local) – minimise the lethality of the cockpit and cabin to flailing injuries
• Post-crash factors – egress and minimise the risk of drowning, fire and fumes.

Container

The occupied cabin area of the aircraft was visible, though significantly damaged from fire and the underside compromised from the ground impact. The outline of the cabin was discernible and displayed dynamic deformation of the structure supporting the front seats and the main spar located underneath the front seats, which is discussed further in the following sections.

Restraint

The pilot and front right seat passenger were ejected from their seats during the accident, and their seatbelt latch plates were found separated from their respective buckles. The rear seat occupant appeared to have remained restrained and was found in the rear right seat location with their seatbelt latch plate attached to the buckle. The pilot was seen wearing a 3-point harness in videos taken during the accident flight. Therefore, it was considered very likely that all 3 occupants were wearing their seatbelts.

According to the build log, the front seats were from a Toyota Prado motor vehicle, and the seatbelts were connected to the seat mounts and airframe with their shoulder straps extending from centre to outboard, where the buckles were located. Regarding seatbelts, AC 21-4(2) para 7.3 stated:

It is strongly recommended that US [United States] FAA [Federal Aviation Administration] Technical Standard Order (TSO) approved or equivalent seat belts be installed along with approved shoulder harnesses. 

According to the build log, the builder conducted load testing of the seat belts in accordance with FAA AC 23-4 Static strength substantiation of attachment points for occupant restraint system installations. This involved the application of a simulated 4G load (400 kg) downwards and forwards to test the seats and seatbelt attachments, which they passed. The TSO specified the minimum performance standards were those in the Society of Automotive Engineers Aerospace Standard AS 8043 (1986), which included the following information:

Pelvic Restraint: A torso restraint system shall provide pelvic restraint whether or not an upper torso restraint is used. Pelvic restraint shall not incorporate emergency locking retractors (inertia reels).

Release: A torso restraint system shall be provided with a single buckle having a single motion release which is readily accessible to the occupant to permit easy and rapid egress by the occupant from the assembly. The buckle release mechanism shall be designed to minimize the possibility of inadvertent release.

A review of car and aircraft seatbelt images revealed a general difference between the design. Car seatbelt latch plates are threaded through the strap connected from the shoulder to the pelvic anchor point on the shoulder strap side. The inertia reel applies the tension, and emergency locking under acceleration, when the latch plate is inserted in the buckle on the opposite side. Therefore, the pelvic restraint (lap belt) incorporates an inertia reel because it is part of the upper torso restraint mechanism. 

The aircraft builder confirmed that this was the design of the front seatbelts fitted to the aircraft and that they were probably car seatbelts. The inertia reel was located at the shoulder anchor point on the inboard side of the seats and the shoulder strap extended down to the inboard pelvic anchor point with the latch plate threaded through the strap. The inertia reels at the shoulder anchor points provided the tension and emergency locking under acceleration for the front seat occupants.  

Seatbelts can fail due to overload, which is why strength tests are conducted, and they can also fail to perform a required function, such as restrain the occupant during a collision. Roberts et al. (2007) described 3 known failure modes associated with car seatbelt design as follows:

• inadvertent unlatching when the buckle is unlatched due to occupant flailing contact with the release button during an accident
• false latching when the buckle fails to engage completely, but gives the user the impression that it is properly fastened due to its partial engagement
• inertial unlatching when the buckle unlatches due to inertial forces resulting from impacts and the associated impulse accelerations during planar collisions and rollovers, which is an example of a component failing to perform a required action.

Energy attenuation

All 3 occupants had fractures of the lumbar spine and the 2 front seat occupants both had crush fractures of the fifth lumbar (L5) vertebra. According to Shanahan (2004) light fixed‑wing aircraft provide little crushable structure to attenuate collision forces. However, 2 areas where energy attenuation can be incorporated into the design are the landing gear and seating. The main landing gear for the Morgan Cougar aircraft was a rigid single-piece structure with the wheel axles attached to the structure. It separated on impact and there were no oleos for energy attenuation incorporated into the design. 

The rear seats were upholstered 4 mm plywood mounted to the cross-members. The front seats were car seats, which were attached to cross-members and had the main wing spar underneath them. The front right seat pan was found collapsed onto the wing spar and the left seat pan had separated and was found forward of the front seat frame structure. None of the seats incorporated any recognisable form of energy attenuation.

According to Stech and Payne (1969), the G-loading strength of the L5 vertebra for a 160 lb (72.6 kg) male is around 25G. The 25G limit was acknowledged by Shanahan (2004) with the following caveat:

However, poorly designed seats can produce spinal fracture in impacts as low as 8-10G. Typically, spinal fractures in low to moderate velocity crashes are caused by mounting seats above rigid panels or other non-frangible objects such as batteries and from mounting relatively rigid seats directly on bulkheads or over beams. In the first case, seats collapse onto unyielding objects causing the occupants to experience excessive vertical accelerations. In the latter case, rigid bulkheads or structural members transmit excessive forces from the ground directly to the seat occupants. 

According to Taylor and Moorcroft (2023) from the FAA Civil Aerospace Medical Institute, special energy attenuating seats are used to provide a controlled deceleration over a vertical stroking distance to keep aircraft crash loads within human tolerance. While there are many methods to achieve a controlled deceleration, some of the simplest and lightest methods include collapsible sheet metal boxes for the seat pan structure and/or the use of rate sensitive foams for the seat pan cushion.

CASA AC 21.4(2) para 7.3 recommended safety considerations for the design of the cockpit and seatbelts to reduce injuries to the pilot and passengers in the event of an accident. It also strongly recommended the use of FAA TSO seatbelts and shoulder harnesses. However, there was no recommendation for the designer or builder to consider energy attenuation for the occupants, specifically the energy attenuation of seating.

Environment (local)

The local environment was not considered to be a significant contributing factor in this accident due to the severity of the occupants’ spinal injuries (indicative of excessive vertical forces) and because the front seat occupants were ejected from their seats. In addition, CASA AC 21-4(2) para 7.3 recommended the ‘delethalization’ of the cockpit as follows:

The design of the cockpit or cabin of the aircraft should avoid, or provide for padding on, sharp corners or edges, protrusions, knobs and similar objects which may cause injury to the pilot or passengers in the event of an accident.

Post-crash factors

The aircraft was designed with a main fuel tank located between the engine firewall and the instrument panel. This made it susceptible to crushing forces in an impact and presented a risk of fuel spray onto the occupants and onto the engine as an ignition source, which occurred in the accident. The fire damage to the aircraft was centred on the cabin and engine area with die-back of the grass evident in a diamond pattern from the initial impact to the point of rest.

The builder modified the original design to incorporate wing fuel tanks in the design, located aft of the main wing spar. The modified wing tanks were not compromised by the collision. The importance of fuel tank location on post-crash survival was described in Johnson et al. (1980 and 1989) Aircraft Crash Survival Design Guide Volume V – Aircraft Postcrash Survival as follows:

The location of the flammable fluid-carrying tank in an aircraft is of considerable importance in minimizing the postcrash fire hazard from a tank installation. The location must be considered with respect to occupants, ignition sources, and probable impact areas.

Greater distance between occupants and fuel supply tends to increase escape time in the event of a fire because it reduces the likelihood of fuel entering the occupied area. Also, the tank should be kept away from probable ignition sources… Another important consideration is the location of tanks with respect to probable impact damage. Accident histories show repeated tank ruptures and consequent fires…, indicating the tank’s high degree of vulnerability to damage from surrounding structures.

As much aircraft structure as possible should be allowed to crush before the tanks themselves are exposed to direct contact with obstructions.

CASA AC 21.4(2) para 7.4 recommended reducing the risk of fire hazard, and the inclusion of a fireproof firewall between the engine compartment and the cabin. However, it did not recommend or advise on how to incorporate crashworthiness into the design of the fuel system.

Pilot information

Qualifications

The pilot held a:

• Recreational Pilot Licence (Aeroplane) (RPL-A), issued by CASA on 6 August 2024, with a single-engine aeroplane class rating and manual propeller pitch control endorsement
• Class 2 aviation medical certificate, issued in June 2024.

The RPL licence was granted in recognition of the pilot holding a recreational pilot certificate (RPC) with RAAus in accordance with Civil Aviation Safety Regulation (CASR) 61.480. In addition, the pilot held an RAAus-issued instructor rating and had accumulated 506.8 hours according to their last logbook entry, dated 7 August 2024. 

Flight training

Recreational aviation flight training

The pilot started flying training with RAAus at Adventure Flight Training (AFT) school in Moama, New South Wales, on 11 April 2022 for their RPC. The pilot passed their RPC flight test on 20 September 2022, and was endorsed with passenger carriage later in 2022, and with navigation and formation in 2023. All flight tests and endorsements were conducted and certified by the AFT chief flying instructor (CFI).[8] 

On 8 May 2023, the pilot started their RAAus instructor training at AFT and passed their instructor flight test at Bendigo, Victoria, on 7 July with an external testing officer. The pilot started delivering instructional flights at AFT on 16 July 2023.

On 19 December 2023, the pilot passed their senior instructor flight test with the AFT CFI and on 3 January 2024, the CFI endorsed the pilot’s logbook with the entry ‘meets the requirements for senior instructor rating iaw RAAus syllabus of flight.’ However, the pilot had not completed the theory exam requirement to be a senior instructor and their rating for senior instructor was not issued by RAAus.

General aviation flight training

The pilot’s logbook had entries for the following general aviation training flights in 2024:

• On 5 June, the pilot started dual flying training in the Pitts Special aerobatic biplane at Latrobe Valley and recorded 0.7 hours.
• On 6 June, the pilot successfully completed a flight review of 2.5 hours duration with a controlled airspace/aerodrome endorsement in a Cessna 152 (a flight review was required to exercise the privileges of a CASA RPL, which was issued in August).
• On 6 June, the pilot recorded a further 0.5 hours of dual flight training in the Pitts Special.
• On 1 July, the pilot recorded 3.1 hours of dual aerobatics training in the Pitts Special.

While the ATSB was informed that the pilot’s flying in the Pitts Special was for the purpose of an aerobatics endorsement, the flight training school (FTS) where the pilot conducted their RPL flight review did not have them enrolled for an aerobatics endorsement. In addition, CASA reported that they did not have an aerobatics endorsement record for the pilot. The ATSB reviewed the pilot’s flight training records for the Pitts Special and concluded that the activities were consistent with transition training onto the Pitts Special, which included stalls and spins, and not an aerobatics course.

The ATSB spoke to a member of a local aerobatics team, who knew the accident pilot, and they confirmed there had been discussions about the possible use of the accident pilot to ferry their Pitts Special aircraft to an airshow at the end of August 2024. However, the pilot did not meet the minimum experience requirements for insurance purposes and the plan was cancelled.

On 9 November 2024, a general aviation flight instructor and RAAus CFI conducted a check flight with the accident pilot at the Echuca Aero Club in the club’s Piper Archer aircraft. This was a requirement to be able to hire the aircraft. The instructor conducted a standard aerial work check flight with the pilot and did not identify any deficiencies in flying skills. 

Theory examinations

Recreational aviation theory examinations

The pilot’s logbook had a record of aviation theory examinations (exams) in accordance with the following table:

Table 3: Pilot's theory exams

The AFT CFI was recorded as the delegate for all of the pilot’s theory exams in their logbook. Another AFT instructor reviewed the exams recorded in the pilot’s logbook and reported that:

• the theory exams were conducted online and unsupervised
• the correct answers to all questions were revealed after the first attempt so that any incorrect answers could be corrected with a second attempt
• no knowledge deficiency reports were provided. 

The ATSB reviewed the software used by AFT to conduct the theory exams and found that the settings allowed multiple attempts and revealed all the correct answers in a report provided to the candidate.

PPL(A)-equivalent examination

To become a senior RAAus instructor, a candidate must pass either the RAAus PPL(A) (aeroplane) equivalent exam, or the CASA PPL(A) exam. The RAAus PPL(A)-equivalent exam was a multi-choice exam in which each question had 4 options to select from. 

On 3 January 2024, RAAus received the pilot’s application for upgrade to senior instructor, certified by the AFT CFI as the examiner, with a copy of the pilot’s instructor exam from 21 May 2023 attached. This exam was completed using the AFT online system. The ATSB did not find a record of the initial response to this application but based on the available evidence, it is likely that RAAus staff identified that the incorrect exam had been submitted in support of the application and reported this to the AFT CFI.

On 12 January 2024, the pilot completed the RAAus PPL(A)-equivalent exam using the AFT online system and a pass mark of 94% was recorded. However, the marking rubric for this exam had not been provided to AFT as this exam was marked by RAAus staff. As no marking rubric was provided, the AFT exam software provider had set answer ‘A’ as the default correct answer to all questions for this exam and notified the AFT CFI of this action. The accident pilot had selected answer ‘A’ to 47/50 questions.

When a copy of the pilot’s exam was provided to RAAus and re-marked it was identified that the actual result for the accident pilot’s exam was 26% (13/50).

On 29 January 2024, RAAus sent an email to the AFT CFI to report the result and express their concern about the result and the process used to mark the exam. They also notified the CFI that the pilot’s application for senior instructor would not be processed and that the pilot would:

• need to complete another PPL(A)-equivalent exam
• continue to require direct supervision (in-person) when instructing.

Re-attempt of PPL(A)-equivalent exam

On 24 February 2024, an external CFI[9] supervised the pilot’s re-attempt of the RAAus PPL(A)-equivalent exam at Moama Airfield. This CFI reported that the pilot arrived with a copy of the exam paper questions and that after the exam was completed, the CFI submitted it to RAAus for marking. They did not follow up as to how the pilot obtained a copy of the exam paper. Instead, they passed the information on to RAAus, who also did not enquire how the pilot had obtained the exam questions.

The AFT CFI reported that they believed the pilot had taken a blank answer sheet and not a copy of the exam paper to the exam. The answer sheet is a document with a table for the candidate to annotate the answer to each question. However, the pilot annotated their answer to each question on a copy of the exam paper, not an answer sheet, and it was this exam paper that was certified by the supervising external CFI and submitted to RAAus for marking.

The second exam result, marked by RAAus, was 76% (37/50), which was less than the required pass mark of 80%. This was the same exam paper, with the same questions and answers, that the pilot had previously attempted in January.

Pilot exam outcomes

The RAAus PPL(A)-equivalent exam included 3 questions about aerodynamic stalling, including about factors that change the 1G level flight stalling speed. For the pilot’s attempt on 12 January 2024, the pilot selected answer A to all 3 questions and they were all marked correct. However, 2 were correct and 1 was incorrect according to the RAAus marking rubric. 

For the pilot’s re-attempt on 24 February 2024, the pilot changed all 3 answers with the result that 1 was correct and 2 were incorrect. While the pilot correctly answered one question that the stall speed increases in a steep turn, they incorrectly answered another question about the relationship between angle of bank, load factor and stall speed.

On 29 February 2024, RAAus sent an email to the AFT CFI to report the failed second exam attempt by the pilot. On this occasion they stated:

Of more concern is the type of errors made, which include several stalling questions and poor Part 91 regulatory understanding among other items. I understand you have already spoken to [the pilot] and advised [them] of this, but I will call [them] to discuss as well.

RAAus expressed concern about the reported preparation process of reviewing current exam papers which ‘could be considered an attempt at rote learning of questions rather than developing a deeper understanding of the underpinning knowledge required of a RAAus Senior Instructor.’ RAAus reiterated previous comments they had made, that the pilot should re-attempt the exam ‘only after appropriate study of aviation textbooks and regulatory references.’ 

The ATSB noted other incorrect questions of concern for an instructor, in addition to the questions about stalling and Part 91 regulations identified by RAAus. They included knowledge of the instruments affected by a blocked static pressure system and the interpretation of an aerodrome weather forecast. The questions about stalling and pressure instruments were in the RPC syllabus, and knowledge of weather forecasts and reports were in the navigation endorsement syllabus. At the time they were attempting the PPL(A)‑equivalent exam, the pilot was delivering instruction for both syllabi. 

The ATSB queried RAAus as to whether they had considered imposing any restrictions or limitations on the pilot’s instructor rating after the second exam result, noting their concern about the pilot’s knowledge deficiencies. RAAus responded that by not processing the pilot’s upgrade to senior instructor, the pilot was required to remain under the direct supervision of a CFI, which was their risk management strategy until the pilot’s knowledge deficiencies could be addressed.

A copy of the 29 February 2024 email sent from RAAus to the AFT CFI appeared on the accident pilot’s RAAus member file. However, the pilot’s member file did not include any record of a follow-up about the exam result or progress towards completing any further attempts. Phone call records indicated that a follow-up from RAAus to the pilot did occur on 29 February 2024, but the details of the call could not be recollected. 

Commercial pilot theory examinations

Instead of studying the CASA PPL theory, the pilot started studying for their CASA aeroplane commercial pilot licence (CPL-A) theory component, which consisted of 7 exams. The pilot attempted and passed their first CPL-A exam on the subject of aircraft general knowledge (CSYA) with a result of 93% on 10 July 2024. The knowledge deficiency report (KDR) had 3 items listed, which indicated a score of 37/40 questions answered correctly. 

On 25 July 2024, the pilot attempted, and failed, the CPL-A aerodynamics exam (CADA) with a result of 63%. The KDR had 15 items listed, which indicated a score of 25/40. The incorrect answers were from a range of topics that included 2 questions on stalling. The 2 incorrect answers on stalling included the effect of using ailerons when approaching and during the stall, and the effect of manoeuvring on the level flight stall indicated airspeed.

On 7 August 2024, the pilot re-attempted the CPL-A aerodynamics exam and passed with a result of 75%. There were 10 items in the KDR, which indicated a score of 30/40. The 2 CPL-A aerodynamics exam KDRs included 3 errors in each of the topics of stalling, stability and control (longitudinal, lateral and directional), and control surface feature. Other items on the KDRs included:

• the lift and drag formulae
• dynamic pressure
• basic forces on an aircraft in level flight
• factors affecting turn performance
• angle of attack required for various flight situations.

Risky flying behaviour and counselling

Background

During the investigation the ATSB interviewed the AFT CFI and associates of the pilot, including:

• 2 other instructors from AFT
• 3 AFT RPC graduates from Moama
• the airport operator, who was also a local aerobatic pilot
• a local general aviation instructor and RAAus CFI. 

Each of them recalled experiencing instances of risky flying behaviour involving the accident pilot, or knowledge of this behaviour and counselling. The ATSB also interviewed RAAus staff to determine if they had received any reports of the pilot engaged in risky flying behaviour.

Risky flying behaviour

A fellow AFT instructor from Moama, who was also a syndicate member in the purchase of the aircraft, reported that the accident pilot had a history of conducting low and slow steep turns. While they had steep turn flying training experience themselves, they were accustomed to entering a steep turn from cruise airspeed and were concerned about the pilot’s practice of entering steep turns at slow speed. They had experienced this personally as a passenger with the pilot, as they were co-owners of a Jabiru aircraft, and were aware of reports of similar instances from the pilot’s students. 

The instructor had also witnessed the pilot conduct dumbbell turns in the circuit with students in light wind conditions. This involved the pilot conducting a reversal turn shortly after take-off to land on the reciprocal runway for student landing practice, rather than completing a full circuit between landings. They suspected the pilot had learned this from the AFT CFI as they had previously witnessed the CFI conduct this same manoeuvre in light wind conditions.

The other member of the syndicate in the purchase of the aircraft was an AFT RPC graduate from Moama in 2024. While they had conducted their RPC at AFT, they did not fly with the pilot until near the end of their flying training, at which point they were doing most of the flying. They did not observe any risky flying behaviour from the pilot but were advised by others at the school that the pilot had previously received counselling for risky flying behaviour.

Another fellow AFT instructor reported that the pilot could fly an aircraft well but ‘pushed the limits’. They recalled an example of a private flight in the pilot’s Jabiru, in which the pilot held the aircraft on the runway as it accelerated significantly beyond the take-off speed and then performed a pull-up into a steep climb. They stated that they immediately asked the pilot to lower the nose.

During the same flight, the pilot reportedly conducted low-level steep turns and a swooping manoeuvre over a friend on the ground. The instructor reported that they repeatedly verbally intervened throughout the flight, and that they didn’t like how the pilot was flying and asked them to stop and return to the airport after about 30 minutes.

Another AFT RPC graduate from Moama reported that during a local recreational flight on 1 November 2024 in the pilot’s Jabiru, which had a stall airspeed of 45 kt, the pilot conducted a low-speed steep turn overhead a friend driving a tractor. The combination of low speed and steep angle of bank made them feel uncomfortable and they assessed that the aircraft did not have sufficient lift for the manoeuvre. The pilot reportedly noticed their discomfort and told them not to worry as they were still at 60 kt (airspeed). ADS-B data recorded a minimum groundspeed of 57 kt during this turn. 

The AFT graduate had previously conducted their RPC pre-check flight with the pilot in August 2023, which included stalls and steep turns in a Topaz aircraft with a stall speed of 44 kt. They reported that the steep turns demonstrated by the pilot then were at least 60° angle of bank, which made them feel uncomfortable and they noted that the pilot appeared to be pushing the aircraft to its limits in a confident manner.

Another RPC graduate interviewed by the ATSB had transferred from the CASA-issued PPL system to the RAAus-issued RPC system and completed their flying training with AFT at Moama. Three days prior to the accident, the pilot invited them on a local area private flight in the accident aircraft. During the flight, the pilot reportedly turned off the transponder and conducted a low-level, high-speed pass over a friend’s house, followed by a wingover.[10] The pilot then demonstrated the responsiveness of the aircraft by conducting a series of level steep turns. The witness reported that the angle of bank was more than 60° and felt like 70–75°, which they described as ‘knife-edge stuff’.

Counselling

The Moama Airfield operator and local aerobatic pilot knew the accident pilot from the AFT school at Moama. The operator had taken the pilot flying in their own aerobatic aircraft and found them to be a very enthusiastic young aviator. Their impression was that the pilot was attracted to the sport aviation side of the industry. In September 2024, the operator was contacted by the AFT CFI about reports of unsafe flying, which included instances of low-level flying and manoeuvring overhead a local football match. 

The airfield operator investigated the reports and found that it was likely the accident pilot who had been conducting steep turns overhead the Moama football ground during a match. They approached the pilot in late September and stressed the need for them to fly respectfully and emphasised staying above the minimum requirements and not to orbit overhead properties. They thought that the pilot accepted the counselling in a positive manner.

A local general aviation instructor and RAAus CFI, who was involved in establishing an FTS near Moama, also received a report that the pilot had been observed conducting aerobatics overhead a local football match. They responded to the reporter that the pilot would not be allowed to instruct for the school with that flying behaviour. The pilot subsequently contacted the CFI and visited them on the afternoon of 1 November 2024 to discuss the reported incident. The pilot was reportedly adamant that they had not conducted aerobatics overhead the football match but acknowledged that they had conducted steep turns overhead the match. 

At the time of the visit, the CFI had also heard reports that the pilot had been conducting dumbbell turns in the circuit with students. Consequently, they used the visit from the pilot as a counselling opportunity, specifically pointing out that a solo student might try to imitate the pilot’s flying and lose control of the aircraft. The CFI thought that the pilot accepted the counselling in a positive manner. 

The AFT CFI reported to the ATSB that prior to the cessation of AFT operations in August 2024, they had regularly engaged in coaching and counselling sessions with the pilot. However, after they ceased AFT operations, they received multiple calls from members of the local community raising concerns about a Jabiru aircraft flying in a manner perceived to be unsafe. While the pilot was not confirmed, the context of the reports led them to believe that the flights were operated by the accident pilot.

The AFT CFI reported that several weeks prior to the accident they had a candid conversation with the pilot and urged them to continue flying safely and responsibly. They stressed that the pilot needed to be even more alert and disciplined without direct oversight. However, as they were no longer responsible for formal oversight of the pilot, they elected to contact others who could potentially mentor the pilot. This included the Moama Airfield operator.

RAAus advised the ATSB that, prior to the accident, they had not received any reports or complaints about the pilot’s flying behaviour, nor were they aware of the pilot receiving any counselling. However, following the accident, they received a report from the AFT CFI that they had been managing the pilot’s behaviour. 

RAAus interrogated their occurrence management system for any complaints involving unidentified aircraft and/or pilots in the Moama region and found none. They stated that if they had received a report of an instructor involved in risky flying behaviour, there would have been a ‘fairly swift response’ because they would not want the individual working as an instructor, and potentially indoctrinating students to that behaviour.

Recreational Aviation Australia

Structure

Recreational Aviation Australia (RAAus) is a CASR (Civil Aviation Safety Regulation) Part 149 approved self-administering aviation organisation (ASAO). In 2025, RAAus had 14–15 full time employees in the following areas:

• flight operations
• maintenance and airworthiness
• safety
• finance
• information technology
• administration. 

According to the RAAus website, they had 10,000+ members in 2025, and were the largest administrator of pilots, maintainers and aircraft in Australia.

RAAus were authorised by CASA to conduct their activities in accordance with their approval certificate, the Part 149 Manual of Standards and their approved Part 149 Exposition. As a sport aviation organisation, RAAus was oversighted by the CASA Sport and Recreation Aviation Branch (CASA Sport). 

The structure of RAAus, with their key personnel in accordance with their Exposition, is depicted in Figure 11.

Figure 11: Recreational Aviation Australia structure

Source: Recreational Aviation Australia

The RAAus Part 149 approval certificate authorised RAAus to administer several aviation administration functions and their sub-functions. The function of relevance to the ATSB’s investigation was Part 149 Flight Training Organisations:

Administer a person that conducts flight training, or flight tests, in relation to a Part 149 aircraft.

The sub-functions were listed as follows:

1. Assessing a person’s organisation, and its procedures, practices, personnel and facilities to determine whether the person is capable of conducting flight training, or flight tests, in relation to the aircraft

2. If satisfied as mentioned in paragraph 1, issuing an authorisation to the person to conduct the activities specified in the authorisation

3. Assessing whether a person to whom the ASAO has issued an authorisation continues to be capable of conducting the activities covered by the authorisation

4. Approving aeronautical examinations that may be conducted by a Part 149 flight training organisation to assess candidates undertaking flight training.

Flight training schools 

In 2025, there were about 160 RAAus flight training schools (FTSs). Student pilots, converting pilots and pilot certificate holders could only undertake flight training with an RAAus FTS approved by the RAAus Head of Flight Operations (HFO). An FTS could only operate when a CFI was approved in accordance with the RAAus flight operations manual (FOM). The FOM also required FTS instructors to be directly supervised by the CFI, or another senior instructor approved by RAAus, with indirect (remote) supervision of senior instructors permitted.

In February 2022, RAAus published version 1.1 of their Recreational Aviation Advisory Publication on instructor supervision requirements. This was published to address the enquiries RAAus had received from their members about the instructions in the FOM. Direct supervision of instructors was in-person and was required to be provided by the CFI or approved senior instructor. The intention of the direct supervision requirement was to ensure the supervisor was physically present at the location where the training was conducted to provide continuing mentoring and development for their instructors.

The CFI oversight responsibilities included 90-day check flights of their instructors and 12‑monthly check flights of their senior instructors, which were called standards and proficiency checks. To become a CFI, an individual was required to progress through the qualifications of RPC, instructor and senior instructor. A senior instructor could be appointed to supervise an FTS in the CFI’s absence if they met the requirements of the RAAus FOM and were approved by the HFO. 

Flight training school exams

Each RAAus FTS qualification had a flight test and one or more associated theory exams. The theory exams were written by RAAus and sent to the FTS CFIs via email. For each exam, answer sheets were provided for the candidates to record their answers to a selection of multiple-choice exam questions. The syllabi for the theory exams were published in the RAAus syllabus of flight training. 

Before accessing the exams, each CFI was required to sign a declaration acknowledging that they had read the conditions of use and would ensure the necessary processes had been implemented at their FTS. The declaration included:

Multiple Choice Examinations. These are not to be distributed and/or reproduced electronically and must be stored securely. 

The FTSs were provided with the marking rubric for each exam and were responsible for marking, filing and recording of the results of each exam. The exception to this was the upgrade from instructor to senior instructor for which the exam requirement was either the CASA PPL(A) exam or the RAAus PPL(A)-equivalent exam. RAAus marked the PPL(A)-equivalent exam and did not provide the FTSs with the marking rubric for it. Prior to 2023, RAAus did not require proof of completion of any exams. In 2023, the RAAus instructor upgrade form was amended to require proof of exam completion for the upgrade to senior instructor only. 

Flight training school oversight 

The RAAus Exposition included an audit program to fulfill sub-functions 1 and 3 of their Part 149 Flight Training Organisations function. Sub-function 1 was for the assessment to issue FTS status while sub-function 3 was for the monitoring of the FTS, which was required to be conducted at least once in every 2-year period.

The RAAus audit activities included:

• desktop
• onsite
• special purpose audits
• health checks
• periodic reviews
• renewals.

The CFI was the only individual from the FTS who was required to be in attendance for an onsite audit and was interviewed as part of the audit process. Other staff members could be interviewed on an opportunity basis, but students were not interviewed as part of a routine audit. 

Given the large number of FTSs and the limited number of RAAus staff available for oversight, RAAus developed a risk and audit matrix to determine the type and frequency of audit activity. The matrix produced a performance indicator (PI) score for each authorisation holder. The RAAus audit manual provided the following statement for FTSs assessed as higher risk:

Where resourcing permits, authorisation holders who fall within the highest 10 PI [performance indicator] scores shall only be eligible for an on-site audit and should be scheduled within the following 6 months. 

When an authorisation holder within the highest 10 PI scores was scheduled for an onsite audit, the audit team would identify other authorisation holders within the local area who would also be audited during the visit.

Occurrence management system 

RAAus had an occurrence and complaints management system (OCMS) database supported by an occurrence and complaints handling manual (OCHM). According to the OCHM:

Any person may report a safety concern or confidential complaint relating to an RAAus member and aircraft. A confidential occurrence may be lodged through the RAAus Occurrence and Complaint Management System (OCMS).

Apart from those OC [occurrences] that are resolved immediately by front line staff, all OC will trigger an informal assessment.

An informal assessment will be made to obtain and assess sufficient information to determine the most appropriate course of action, including the possibility of a Safety Related Suspension [SRS] if a serious safety situation is indicated.

The OCHM described the SRS as follows:

Temporary suspension of a member’s privileges, through imposing an SRS, is a risk management strategy that will be considered if:

a. the potential risk (to self, other RAAus members, members of the public, the organisation or the effective conduct of the investigation) posed by the member continuing to fly, or maintain aircraft, is significant; and/or

b. the potential risk to others posed by the member cannot reasonably be managed in any other manner.

The AM [Accountable Manager], HAM [Head of Airworthiness and maintenance] or HFO may decide to impose an SRS on a member.

The OCHM provided the following examples of an SRS:

a. enhanced supervision requirements

b. temporary suspension of certificates

c. temporary revocation or restriction of privileges.

In accordance with CASR 149.425 and the RAAus Exposition, RAAus was required to submit a written report to CASA within 7 days of taking formal compliance or enforcement action. This was described in the RAAus formal inquiry process.

RAAus advised that mandatory notification to CASA was not required following an SRS because it was part of their informal assessment process and not their formal inquiry process. However, they could notify CASA of an SRS at their own discretion if they considered it prudent, although there was no continuing reporting requirement associated with this.

The outcome from an informal assessment could include a requirement for remedial action to be completed prior to lifting an SRS. If an individual’s membership lapsed with an active SRS, the requirements remained in place, flagged in their RAAus member profile, and were to be completed prior to exercising the privileges of their RPC if they decided to reactivate their RAAus membership.

Adventure Flight Training

Background

The AFT CFI became a member of RAAus in December 2008 and was issued with an RPC in December 2009, instructor rating in April 2017 and senior instructor rating in July 2018. On their senior instructor upgrade submission to RAAus, the examiner certified that the ground theory component was satisfactorily completed, although proof of completion of the ground theory was not required and not provided. Proof of a current medical certificate was required and provided. 

As previously described, the theory component for the upgrade to senior instructor could be met by either passing the CASA PPL(A) exam or submitting the RAAus PPL(A)‑equivalent exam for marking by RAAus. In the case of the AFT CFI’s senior instructor upgrade, RAAus reported that the answer sheet for the PPL(A)-equivalent exam was not received with the upgrade submission and that it was likely their administration staff believed that the CASA PPL(A) exam had been completed instead. The CFI reported to the ATSB that for their senior instructor upgrade, the RAAus PPL(A)‑equivalent exam was done, submitted and approved.

The CFI was issued with a certificate of approval for their FTS on 11 June 2019. This followed an FTS inspection report in May 2019 at the nominated location of Riddell Airfield (Riddell), Victoria, and was initially to provide training for the issue of an RPC. The first 3 RPC candidates were required to be independently assessed by an RAAus‑nominated examiner. 

In October 2021, RAAus issued the CFI with temporary approval for instructor training IT(T). This required the first 3 candidates for their instructor rating to be independently assessed by an RAAus-nominated examiner before the temporary approval could be lifted. In May 2022, RAAus conducted an onsite audit of AFT at Riddell. 

RAAus records indicated that on 6 March 2023, the primary location for AFT became Moama. In August 2024, RAAus imposed an SRS on the CFI, which suspended their CFI approval and senior instructor qualification. Subsequently, the CFI elected to cease the FTS operations and later sold AFT. 

Practices at Riddell Airfield 

As part of the investigation, the ATSB interviewed the AFT CFI, 2 AFT instructors who were peers of the accident pilot, and several AFT RPC graduates from Riddell and Moama Airfields, all of whom knew the CFI and the accident pilot. 

The interviews with those who had trained at Riddell indicated that AFT operations appeared to be consistent with the RAAus Exposition for an FTS, which was the situation when AFT was audited by RAAus in May 2022. One RPC graduate from Riddell reported that it was a more positive learning environment than they had previously experienced in general aviation.

The CFI would deliver the theory during the classroom lesson, then demonstrate the manoeuvre in-flight before handing over control and directing them how to fly the manoeuvre. Theory exams were paper-based using the exam papers provided by RAAus, which were supervised, marked and debriefed by the CFI. 

However, what also emerged from the interviews was a difference in the FTS practices between Riddell in the period 2019–2023 and Moama in the period 2022–2024.

Onsite audits 

In May 2019, RAAus conducted an initial FTS inspection at Riddell, and an FTS inspection report was completed by the RAAus delegate. No non‑compliances or rectifications were recorded on the report. At the time, there were no satellite flight training facilities and therefore the requirement for inspections of these facilities was recorded as not applicable on the report. 

The next onsite audit of AFT was conducted at Riddell by RAAus in May 2022, at which time Moama was recorded as a satellite facility. That audit only occurred by virtue of AFT being at the same airfield as another FTS at Riddell being audited due to their PI being in the top 10. RAAus reported that, prior to that audit, AFT was ranked about 20 based on their PI score. 

RAAus reported that during the 2022 audit they checked the records of student exam results but would not have checked the exam papers (answer sheets) themselves. One member of the audit team recalled a discussion with the CFI about the use of an online exam system as part of a broader discussion about how to improve the administration of the FTS. They did not believe an online exam system was in use, and they did not review or approve one. 

The 2022 audit report included a reference to checking exam results but no reference to the use, or discussion, of an online exam system. RAAus reported that they had declined requests by FTSs to use online systems because it conflicted with the CFI declaration to not distribute the exams in either electronic or paper form.

On review of the draft report, the CFI maintained that RAAus did approve their online exam system and that they demonstrated it to 2 of the auditors during the 2022 audit. They further reported that during the audit they reported that exams were completed and stored electronically and demonstrated this in accordance with the respective audit checklist item. However, the auditor’s annotation on the 2022 audit report next to this item indicated ‘Cloud based (Google Drive)’ and did not include reference to the online exam software platform.

The audit resulted in 2 required corrective actions and 5 observations with associated recommendations. The AFT CFI responded to the corrective actions required and observations, which were accepted by RAAus. A copy of the audit closure report with the accepted supporting evidence was sent to the CFI in August 2022. 

RAAus reported that, depending on findings, an FTS did not automatically move to the bottom of the PI score list after an audit. In this instance, because of the structure of AFT and the non-compliances identified during the audit, their rank moved from about 20 to approximately 100 (of about 160 FTSs at the time).

Chief flying instructor conduct

In May 2020, RAAus investigated a close proximity event involving the AFT CFI, which their risk matrix indicated was a potentially catastrophic event. The CFI denied involvement in the event and reportedly provided RAAus with a copy of their flight path history for the day of the incident. However, the RAAus investigation confirmed it was the CFI’s aircraft and that they were aboard at the time. RAAus subsequently issued a formal letter of reprimand to the CFI for not reporting the event and denying their involvement.

In August 2020, the initial cadre of AFT RPC candidates were ready for assessment, and an independent examiner was nominated by RAAus. The examiner assessed the first candidate and reported to RAAus that the flight component of the test went smoothly but the candidate’s theory knowledge was ‘not as good as it could have been’. The examiner recommended the candidate do further theory practice exercises. 

RAAus correspondence indicated that following the independent assessment of the first AFT RPC candidate, the CFI conducted the flight tests for the 2 other RPC candidates, instead of having them assessed by the nominated examiner as required. When RAAus challenged the CFI about this matter, they alleged that the examiner had lost control of the aircraft during the flight test with their candidate. This allegation was later challenged by the examiner and the CFI provided RAAus and the examiner with a retraction.

On review of the draft report, the CFI denied that they had made this allegation and reported that the student had told them the examiner was flying out of balance. Therefore, the CFI decided to request another examiner with experience on that aircraft type conduct the checks. 

In December 2020, RAAus lifted the RPC testing restriction on the CFI with an administrative assessment in place. This allowed them to conduct the flight tests for the recommendation of an RPC but required them to provide RAAus with each candidate’s completed training records when the RPC recommendation paperwork was submitted.

In November 2021, about a month after RAAus issued the CFI with their instructor training temporary approval (IT(T)), the CFI advised RAAus they were starting a full-time IT course at Moama Airfield. Like the first 3 RPC candidates, the first 3 candidates for the instructor rating were required to be independently assessed.

In April 2023, the CFI reported to RAAus that their first 3 instructor candidates had been independently assessed and requested removal of their temporary IT status. However, the examiner on this occasion (different from the previous RPC examiner discussed above) reported that the candidates were not prepared for their instructor briefing session despite the preparation advice the examiner had provided to the CFI for their candidates. 

The examiner also reported that there were additional administration preparation deficiencies, which led them to conclude that the CFI had not taken the time to check the process requirements. Consequently, in May 2023, RAAus notified the CFI that they would need to remain under a temporary IT approval status until a further 2 candidates could be assessed by the same examiner. The RAAus records indicate that the temporary IT approval was never lifted. 

Practices at Moama Airfield

Pre-flight video briefs

The accident pilot started flight training with AFT at Moama in April 2022 with operations temporarily moving to Echuca, Victoria, during the flooding of Moama in late 2022. Staff and students interviewed by the ATSB who attended Moama from late 2022 through to the closure in August 2024 reported that no pre-flight briefings or post-flight debriefings were delivered for RPC candidates. Instead, the CFI had produced a short in-flight video for each of the RPC flight training elements, which demonstrated how the manoeuvres were to be flown, and candidates reported they had to pay a subscription fee to access AFT flight training videos for pre-flight briefing material. 

On review of the draft report, the CFI reported that the videos were gradually introduced from 12 July 2023 to 22 July 2024. Therefore, the videos were not used for the delivery of training to the accident pilot, which they reported was delivered in-person.

The CFI reported that the videos were only introductory material and not the pre-flight briefing material. However, the CFI’s position was contradicted by the Moama AFT instructor staff and students interviewed by the ATSB. Additionally, the ATSB noted that the syllabus used by AFT staff included the following items:

Confirm student has watched the relevant video briefing and understood the concepts

Remind students to login to AFT members page and watch next video

According to RAAus, their Exposition did not prohibit an FTS from implementing pre-flight video briefings in lieu of in-person pre-flight briefs. However, RAAus advised being unaware of the videos prior to suspending the CFI in August 2024. RAAus learnt about the videos from interviews with AFT members about the practices at the FTS. However, they were then told by the CFI that access to the videos was no longer available and therefore, RAAus reported they were unable to assess whether the content of the videos was adequate. 

The ATSB interviewed an RAAus CFI, who was also a CASA flight instructor, and who had reviewed one of the videos. They reported that they didn’t think the video met the quality required for a pre-flight brief. Another RAAus CFI, who had reviewed several of the videos for the AFT CFI, reported to the ATSB that they had been led to believe that they were the pre-flight briefing material and that they were inadequate due to deficiencies in the quality of instruction presented.

They noted that, while the AFT CFI was projecting a friendly demeanour in the videos, it was often at the expense of technical errors and an adequate demonstration. For example, the reviewer noted the stalling video did not include any reference to the effect of load factor on stall speed and reference to checks and limits were often omitted in the various videos. 

The ATSB obtained copies of 12 of the AFT videos from elements of the RPC syllabus, one produced in 2020 and the remainder in 2023. This evidence was consistent with a report the ATSB received from a Moama AFT instructor that they were already receiving video briefs when they started flying training in late 2022. They ranged in length from 2 minutes and 15 seconds to 7 minutes and 30 seconds. Of specific interest to the ATSB investigation was the aerodynamic stalling video, which was of 6 minutes duration.

In that video, the CFI demonstrated the reduced effectiveness of flight controls near the stall by applying full left then full right rudder and instructed the use of rudder to level the aircraft if a wing drop occurred. The risk of inducing a spin from large rudder applications near the stall was not mentioned. By contrast, the CASA flight instructor manual for aeroplanes explained these points in its chapters on stalling and spinning as follows:

Emphasize that if a wing drops, rudder is used to prevent yaw into the direction of the lowered wing. The wing is raised with aileron when it is un-stalled.

An aeroplane is made to spin, whether accidentally or deliberately, by faulty use of the controls particularly the rudder.

During the stalling video, the CFI explained that lowering the flap for the configured stall demonstration would ‘thicken’ the wing, and that the thicker the wing, the slower they could fly. The manufacturer’s website for the demonstration aircraft stated that it had a slotted flap. A slotted flap is a design feature used to control the boundary airflow layer and increase the camber of the wing. Lowering the flap increases the maximum coefficient of lift (and drag) for the wing, thereby allowing the aircraft to fly and stall at a lower airspeed and is part of the basic lift formula. 

At the start of the video, and in accordance with the RAAus syllabus of flight element of stalling, the CFI demonstrated the pre-manoeuvre checks. However, there was no reference to flap limiting speeds for the configured stall and no demonstration of post loss of control checks after recovery from any of the stalls. The RAAus syllabus of flight included ‘airframe limitations’ as a competency requirement within the element of stalling.

Demonstration of stall at greater than 1G

For the RAAus RPC syllabus, stall exercises were limited to straight and level, clean and configured stalls, with and without wing drops, which were covered in the AFT video. However, the RPC theory syllabus did require a thorough understanding of the relationship between load factor and stall speed and the instructor syllabus included demonstration of stall entry at greater than 1G (critical angle of attack exceeded at a higher airspeed). In the AFT stalling video, the CFI directed the viewer’s attention to the lower stall speed when the flap was lowered for a configured stall, but a higher stall speed, and what contributes to a higher stall speed, was not demonstrated or discussed. 

The CFI reported that the demonstration of stall entry greater than 1G was conducted in training, but the 2 AFT instructors interviewed by the ATSB reported they did not conduct this manoeuvre during their training. One of the instructors reported that they were unaware of the effect of load factor on stall speed at the time of the accident and that both themself and the accident pilot were trained in stalling by the AFT CFI for their instructor course. Therefore, they believed the accident pilot would not have covered this topic either. Their main concern with the load factor applied by the accident pilot during steep turn manoeuvres was the potential for a structural failure.

While the CFI reported that the ‘greater than 1G stall manoeuvre’ was taught as a turning stall during training, they were unable to recall the parameters used for the demonstration. The AFT records for their instructor training courses included comments about clean stalls, configured stalls and wing drops. However, there were no references to a stall at greater than 1G.

The AFT RPC student records indicated that the element ‘critical angle of attack exceeded at a higher airspeed’, was assigned a competency code on 46 out of 55 occasions. This was despite it not being in the RPC syllabus and the AFT instructors interviewed by the ATSB reporting that they had never done it in training themselves or with a student. One instructor explained that the competencies for each flight were accessed during the flight with a portable electronic device, such as a smartphone, and that on a small screen, instructors might have only registered the start of the competency, which stated ‘critical angle of attack exceeded…’, without either registering or understanding the meaning of the rest of the competency, which stated ‘…at a higher airspeed’. 

Online exams

The AFT instructor interviewed by the ATSB, who started flying training with AFT at Riddell Airfield, reported that they followed the RAAus paper-based exam system, as previously described, and that they had no experience with an online exam system. However, the other instructor interviewed by the ATSB, who started at Moama Airfield (Echuca during the floods), conducted their exams at home, unsupervised using their own login to the AFT online exam system. This was the same process described by the AFT RPC graduates from Moama interviewed by the ATSB. 

The CFI reported that the online exam system was set up in response to the COVID lockdown period and was approved by RAAus. The setup of the system entailed the CFI providing a copy of each exam paper and marking rubric to the software platform provider for loading onto their platform. The exception was the RAAus PPL(A)-equivalent exam, which was marked by RAAus and therefore no marking rubric was provided. The CFI reported that the software provider loaded answer A as the default correct response to all questions for the PPL(A)-equivalent exam and notified them of this action.

The AFT cohort who used the online exam system paid a subscription to access the exams and were notified by the CFI or their instructor when they were due to complete an exam. The CFI was the administrator for the online system and reported that the security protocols prevented anyone else from downloading or printing a copy of an exam paper. As the administrator, the CFI included settings which allowed 2 attempts at each exam and revealed the correct answers to all questions in the exam report, provided after the first attempt. 

One of the Moama RPC graduates reported there was no study direction before an online exam and that the staff expected they would pass each exam on a second attempt if required. This graduate reported there were no classroom lessons, in addition to no in‑person pre-flight briefs, and the lack of theory education caused them progression problems and learning difficulties with some of the technical aspects. 

Another Moama RPC graduate, who had prior non-aviation teaching experience, believed the online exams were open-book as they were unsupervised. Consequently, they used their flight training reference books during exams, supported by online searches for any questions they could not find the answer to in their books.

They did not pass their first attempt at the basic aeronautical knowledge exam but received all the correct answers in their exam report, which they photographed and used for their second attempt. They did not receive any classroom lessons or pre-flight briefings at AFT and reported that they felt the learning experience was substandard.

The RPC graduate had 2 attempts at the basic aeronautical knowledge exam on the same day recorded in the AFT exam records, with a score of 100% for both attempts. One of the AFT instructors reported to the ATSB that the exam scores were manually entered and might not have represented the actual results. Of the 146 entries in the AFT exam records, from April 2021 to July 2024, there were no failures.

Deficient instructor supervision

As previously described, on 19 December 2023, the AFT CFI conducted the senior instructor flight test for the accident pilot and incorrectly submitted the upgrade application to RAAus with a copy of the pilot’s May 2023 instructor exam, which had been conducted online. On 3 January 2024, the CFI certified in the pilot’s logbook that they met the requirements for the senior instructor rating in accordance with the RAAus syllabus of flight. The pilot subsequently took the RAAus PPL(A)-equivalent exam online on 12 January 2024. 

The pilot scored 94% (47/50), noting answer A was the default correct answer for all questions, and which the CFI reported that they were aware of. The CFI then submitted a copy of this exam to RAAus, noting that they reported that they were the only one who could download the exams from their online platform. 

In late January, RAAus notified the CFI of the pilot’s failure assessment for the PPL(A)‑equivalent exam, that the pilot’s upgrade to senior instructor would not be processed and that the pilot would continue to require direct supervision as an instructor. However, in January 2024, the CFI left the FTS for extended travel around Australia throughout the calendar year 2024. 

Prior to leaving, the CFI enquired with another RAAus CFI if that person could hold a temporary CFI position for them while they were away. However, they were told by that person that they could not attend the FTS in Moama and were therefore unable to comply with the direct supervision requirements for the AFT instructors. There was no reference in the AFT CFI’s RAAus member record of their absence from their FTS and RAAus reported they had no knowledge that the CFI had departed from the area and left their instructors without direct supervision.

The accident pilot’s last logbook entry was an AFT instructional flight on 7 August 2024 and their last check flight with the CFI was their senior instructor flight test on 19 December 2023. There were no entries in 2024 for a standards and proficiency check from the CFI, which was required every 90 days. 

The AFT training records indicated that the CFI was at the FTS until at least 11 January 2024 and returned to deliver training for several days in February, May and June of 2024. One of the AFT instructors reported they didn’t get a check flight from the CFI during one of the visits, which concerned them as they considered themself and the other instructors at AFT to be relatively ‘green’.

The other AFT instructor reported that the flights they conducted with the CFI during this period were ferry flights between Melbourne and Moama when the CFI visited the FTS to deliver training. The 3 AFT instructors all qualified in 2023_; one in early 2023, the accident pilot in mid-2023 and the third in late 2023.

Examination conduct

As previously described, the accident pilot unsuccessfully re-attempted the PPL(A)‑equivalent exam on 24 February 2024. At the end of February, RAAus emailed the CFI the result from the pilot’s second attempt at the exam and their concern about the type of errors made. They also advised the CFI that it was critical for the CFI to also complete the PPL(A) exam as they had delivered the instructor training for the accident pilot and RAAus could not confirm that the CFI had previously completed the PPL(A) exam. 

In response, the CFI reported to RAAus that it was their intent to complete a PPL(A) course and the CASA PPL(A) exam. RAAus noted this but also committed to revising their PPL(A)‑equivalent exam by the end of March as an alternative pathway. In late March, RAAus requested an update from the CFI on their progress towards attempting the PPL(A) exam. The CFI reported that both they and the accident pilot were enrolled in a course but could not provide an estimated completion date. 

On 2 July the CFI submitted a completed exam paper to RAAus for the same version of the PPL(A)-equivalent exam that the accident pilot had failed in February (2022 version). However, RAAus noted that their policy for exam conduct, published at the front of the exam paper, was not followed. Specifically, a supervisor for the exam was required to be appointed by RAAus, the exam answer sheet should have been used instead of the exam paper, and the supervisor should have submitted the exam to RAAus for marking, rather than the candidate (the CFI themself). 

RAAus communicated the problems they identified to the CFI, and they subsequently received a copy of the exam answer sheet, with a supervisor’s signature dated 4 July. The answer sheet provided was marked by RAAus and scored as a pass (88%). RAAus prepared a knowledge deficiency report with the pass result for the CFI and annotated the exam location as ‘Supervised via zoom (possibly at Moama)’. 

On 8 July, RAAus followed up with the certifying supervisor on several points, which included:

Their instructor approval had lapsed in January and therefore their supervisory privileges had also lapsed.

How were they given approval to supervise the exam as the policy document states that the RAAus HFO makes these arrangements?

Exams require direct supervision, which is in-person, whereas the use of Zoom indicated indirect supervision.

The supervisor’s certification date of 4 July was 2 days after the exam paper was submitted to RAAus.

There was no record of answers to these queries, but RAAus subsequently concluded that the CFI’s exam result was invalid. At the end of July, they communicated to the CFI that either the CASA PPL(A) or a new RAAus PPL(A)-equivalent exam needed to be taken prior to 16 August 2024. 

The CFI notified RAAus on 7 August that they would attempt the PPL(A)-equivalent exam if it could be facilitated for them in Far North Queensland. This was arranged for 8 August with a copy of a new RAAus PPL(A)-equivalent exam (2024 version). The 2024 exam paper comprised 60 questions, of which 50 were the same, or similar, to the 2022 version. The CFI scored 77% (46/60), which was below the required pass mark of 80%. 

The CFI reported to the ATSB that other CFIs had told them that they too could not pass the 2024 version exam paper, and the CFI did not believe the exam had been validated and therefore should not have been used. They provided a specific example of a navigation question they believed was marked as incorrect because they used a protractor rather than the ‘1-in-60’ rule to calculate their answer to a heading correction question. However, the ATSB identified that it was possible to derive the correct answer using either method. 

The ATSB also noted that the CFI provided the same incorrect answer as the accident pilot to a question about the relationship between angle of bank, load factor and stall speed. They had both selected the answer with the correct stall speed but the incorrect load factor. The RAAus syllabus of flight training contained the references for the navigation and stall speed questions.

The marking of the CFI’s answer sheet revealed there were 13 incorrect answers in the first 50 questions (7 in common with the accident pilot) and 1 incorrect answer in the 10 additional questions. Consequently, if only the 50 questions from the 2022 version exam were marked, the score would have been 74% (37/50) and remained below the pass mark. 

Safety related suspensions

On 9 August, RAAus notified the CFI of the failed exam result and that the exam had been crosschecked by 2 independent staff. They then issued an immediate SRS, suspending the CFI’s senior instructor rating, which was required for a CFI approval. To remove the SRS, the CFI was required to supply RAAus with evidence of a pass result for the CASA PPL(A) exam. RAAus reported to the ATSB that they were prepared to arrange for a temporary CFI for AFT in the interim, but the CFI decided to cease FTS operations and later sold AFT.

On 13 August, RAAus notified CASA of their implementation of the SRS for the AFT CFI and that the matter was currently under review. The notification to CASA included:

• RAAus identification of incorrect marking of a PPL(A)-equivalent exam for a senior instructor candidate, which raised questions about the CFI’s theoretical knowledge
• advice of the CFI’s failed attempt at the PPL(A)-equivalent exam, with a conclusion that they therefore did not meet the theoretical knowledge requirement for the senior instructor rating and would need to provide evidence of a pass for the CASA PPL(A) exam. 

On 11 November, RAAus notified the AFT CFI that they had completed an informal assessment as per the OCHM and did not believe a formal inquiry was necessary. They reiterated that the remedial action required was the completion of the CASA PPL(A) exam. However, by that time the CFI’s membership had lapsed. RAAus reported to the ATSB that the remedial action requirement would remain flagged in the system in the event that the CFI elected to re-activate their membership and have their senior instructor rating reinstated.

Following the accident, on 19 December 2024, RAAus issued an SRS notice to all RPC graduates from AFT who did not hold a CASA PPL(A) licence or higher. This was due to non-compliances with the conduct and supervision of exams, which meant they could not verify that former students met the theoretical knowledge requirements for the issue of an RPC. 

Civil Aviation Safety Authority

Surveillance events

The CASA Sport and Recreation Branch (CASA Sport) conducted a Level 1 surveillance event of RAAus at their premises between 12–14 April 2023, and a Level 2 surveillance event at their premises between 3–5 September 2024. Prior to 2023, the previous audit was a Level 1 surveillance event on 4 May 2019. The ATSB obtained a copy of the previous 2 audit reports (2023 and 2024) of RAAus by CASA.

The May 2019 audit resulted in 1 finding and 6 observations. The April 2023 audit resulted in 4 findings and 7 observations. The 4 findings related to the elements of airworthiness and listing of aircraft and were not relevant to the ATSB’s investigation. However, one observation of relevance from the 2023 audit was for the element of Evaluation of Authorisation Holders, as follows:

The processes for the regular evaluation of holders of certain authorisations to ensure compliance with the requirements set out in the ASAO’s policies and procedures require additional development. 

As this was an observation, no response was required from, or provided by, RAAus. The September 2024 audit of RAAus followed their notification to CASA Sport of the SRS issued against the AFT CFI and the introduction to the audit report stated:

The auditors sampled the systems and elements relating to RAAus' oversight of flight training schools with the respective key personnel and the RAAus Accountable Manager. Emphasis was placed on reviewing:

• the integrity of their training/testing system which leads to the granting of pilot authorisations,

• governance and process including consistency,

• oversight of training and examining,

• safety assurance including the reliability of information provided by examiners.

CASA Sport raised 2 observations from the audit for competency-based training, and interpretation of manuals, which were both against the element of Flight Operations (Pilot Authorisations). No responses were required or provided to the observations. The observation about competency-based training had a similar theme to the 2023 audit observation about compliance issues and stated:

Current updates to the Flight Operations Manual (Version 8) places significant reliance on CFIs and Examiners applying competency-based training and testing outcomes. However, one of the highest individual non-compliances identified from the RAAus Risk and Audit Matrix Occurrence Tracker records has been deficiencies in the FTS applying and recording competency-based training outcomes (assessing and recording competence and rectifying deficiencies). 

The non-compliances found by RAAus auditors during the audits of FTSs - with more than 30% of the RAAus FTS surveillance events (conducted between Dec 2021 and August 2024) showing a non-compliance in relation to assessing and recording competencies - may suggest a level of guidance regarding competency-based training for FTS may be required.

Pilot examination office 

The CASA pilot online examination system is called the pilot examination office (PEXO). The key personnel in the daily operations of an examination centre are the registrar and invigilator. A registrar is responsible for making the booking of exams for candidates and an invigilator is responsible for the direct supervision of the candidates for their exams. An individual may hold both the registrar and invigilator positions.

Registrars, invigilators and examination centres must be authorised by CASA and the approval for FTSs to conduct exams is limited to PPL and the private instrument flight rating (PIFR). Therefore, a candidate for a commercial pilot licence, which is a requirement to instruct for the issue of a pilot licence, would need to pass their higher‑level theory exams at an examination centre independent of their FTS.[11]

The registrar, invigilator and candidate each have their own unique password, which limits their access within the system to their specific functions. CASA records access and usage of the PEXO system and provides an e-learning module for the system users (registrars, invigilators and candidates). They also undertake surveillance of examination centres, which may, or may not, be conducted with advance notice. 

The exams are accessed by connection to the CASA server during an examination. When an exam is started, the questions and associated answers will be generated from a database of questions, and a timer will count down. The program will automatically close the exam when the time has expired or if the candidate selects ‘End’ exam and ‘logout’. After the candidate selects ‘End’ exam, it will be automatically submitted for marking and the result recorded against the candidate. The invigilator login is needed to recover the result and the associated knowledge deficiency report for the candidate. 

Granting of a Recreational Pilot Licence

Under CASR Part 61.480, CASA can grant an RPL to an individual on the basis of them holding a pilot certificate, granted from certain organisations, which included RAAus. In this scenario, the applicant is taken to have passed the aeronautical knowledge examination and flight test for the licence and associated aircraft category rating issued.

The applicant is also taken to have met the requirements for the aircraft class rating and design feature endorsements for which the applicant is permitted by their pilot certificate to act as the pilot in command. However, they must successfully complete a flight review for their class rating in order to exercise the privileges of their rating. In the case of the accident pilot, this was a single-engine aeroplane class rating.

Mandatory reporting and enforcement process

Background 

Under CASR Part 149.425, RAAus have mandatory reporting requirements to CASA Sport in accordance with their Exposition and the circumstances prescribed by 149.425. If RAAus reported to CASA Sport that they had revoked or suspended a member’s qualification(s), then the matter could be referred by CASA Sport to the CASA Coordinated Enforcement Process (CEP), which is described in the CASA Enforcement Manual.

Under the CEP, the matter is referred to the Coordinated Enforcement Meeting (CEM) where it is allocated to an investigator to investigate and provide a report to the CEM for discussion on whether to proceed with action. The participants in the CEM have a range of options, which include, but are not limited to, the following:

• no action
• education
• counselling
• direct the person to undertake examinations
• suspend authorisations pending completion of a practical or theoretical examination
• varying, suspending or revoking a licence, endorsement or rating.   

Response to RAAus safety related suspension notices 

On 19 December 2024, RAAus issued an SRS notice to all RPC graduates from AFT who did not hold a CASA PPL(A) licence or higher. The notice explanation included the following:

RAAus has identified non-compliance with respect to the conduct and supervision of exams conducted by students at Adventure Flight Training. Based on the evidence available, RAAus is unable to verify that all former students of Adventure Flight Training met the required theoretical knowledge standards required for the issue of a Recreational Pilot Certificate with RAAus. 

Due to the potential for this finding to result in a risk to aviation safety, RAAus has implemented a safety related suspension (SRS) on your Recreational Pilot Certificate (RPC), effective immediately, pending the conduct of an assessment to confirm that your theoretical knowledge meets the expected standard required to maintain an RPC.

On 20 December, RAAus notified CASA Sport of the implementation of the SRS following their ongoing investigation into how AFT was being managed. Their notification to CASA did not include the names of the affected members, but did include the following explanation:

It has been identified that some students undertook RAAus exams using an online system from their home address without the supervision of an instructor. Further, it has been identified that the system used to sit exams online allowed the student to update incorrect answers and resubmit the exam to achieve a successful pass mark.

The process for the affected members to remove their SRS included passing the RAAus converting pilot exam (a requirement for a pilot licence holder applying for an RAAus RPC) under the supervision of an FTS CFI or senior instructor. The exam supervisor also had the discretion to require additional theoretical assessments and one of the AFT instructors subject to the SRS reported to the ATSB that in addition to the converting pilot exam, they were also required to complete the RAAus instructor exam. The instructor also reported to the ATSB that they held a CASA-issued RPL (issued in recognition of their RPC) but CASA had not contacted them about continued exercising of the privileges of their CASA-issued licence.

CASA reported that they recorded all information provided by RAAus in their records management system but no follow‑up was conducted with RAAus to identify the specific members affected. RAAus reported that they elected to voluntarily provide the initial SRS (August 2024) about the AFT CFI to CASA as it involved a higher approval holder. When the AFT graduates’ SRS was implemented in December, RAAus considered that it would be prudent to notify CASA due to the number of pilot certificate holders involved.  

The ATSB obtained a list of the affected members from RAAus, about 7 months after the SRSs were issued, and requested CASA review it against their RPL records. It was identified that 3 affected members held a CASA-issued RPL, granted based on their RAAus RPC, which included 2 at the time the SRS was issued.

Two of those 3 members addressed the SRS within a month of its issue. The third had not addressed it and their RAAus membership had lapsed, which meant that they continued to hold a CASA RPL without restrictions, while their RPC was suspended and would not be lifted unless they re-activated their membership. 

Safety analysis

Introduction

On 16 November 2024, an amateur-built experimental certificate Morgan Cougar Mk 1 aircraft, registered VH-LDV, with a pilot and 2 passengers on board, departed from West Sale Airport, Victoria, for a local area flight. The aircraft collided with terrain in a paddock 19 km north-north-west of West Sale Airport about 17 minutes after departure and shortly after commencing a series of orbits. The aircraft was destroyed and the 3 occupants fatally injured. 

This analysis will discuss the factors that contributed to the accident sequence, including the loss of control and the pilot’s knowledge deficiencies and history of risky flying behaviour. It will also discuss the management of the Adventure Flight Training (AFT) school and the Recreational Aviation Australia (RAAus) examination system. 

In addition, the analysis will examine the aircraft’s occupant restraints, aircraft design and guidance material from the Civil Aviation Safety Authority (CASA) advisory circular for amateur-built experimental certificate aircraft and transition training guidance for buyers of these aircraft. Finally, it will discuss the CASA Sport and Recreation Aviation Branch management of suspension notices received from RAAus.

Accident sequence

Loss of control

Analysis of the final 3 minutes of the flightpath revealed the aircraft’s speed and height were decreasing as it flew a series of turns and orbits. When the aircraft commenced the final turn, the groundspeed and height above the ground had reduced from 103 kt and 716 ft, to 64 kt and 269 ft. Using the recorded local mean and gust wind, the estimated calibrated airspeed was in the region of 67–74 kt at the start of the final turn. The groundspeed reduced to 56 kt during the final turn as the turn radius tightened and analysis of this turn indicated a steep turn with an average 45° angle of bank required for the observed flight path.

A closed-circuit television camera at a nearby farm recorded the aircraft enter the final turn with an angle of bank consistent with a steep turn manoeuvre. The aircraft then pitched nose down at an estimated airspeed of 59–65 kt and height of about 220 ft. Witnesses reported that the aircraft appeared to fall from the sky, and the recorded data indicated an abrupt reduction in altitude and increase in speed. The witness accounts, recorded data, and camera footage were consistent with a loss of control due to an aerodynamic stall.

Wreckage examination found the aircraft attitude was recovering towards straight and level just prior to impact and that the engine was operating at impact. This indicated that it was very unlikely that a mechanical fault contributed to the accident. The amount of engine power at impact could not be determined and the ATSB could not rule out the possibility that the pilot retarded the power lever towards idle in response to the loss of control, which would be the expected response to a nose-low unusual attitude.

The final turn started 7 seconds prior to the stall, at which time the aircraft was estimated to be 29–36 kt above the flight test recorded stall speed of 38 kt in straight and level flight. For a stall to occur in 7 seconds after starting the turn, it required a closure rate of 4–5 kt per second to the stall speed, which was consistent with an accelerated stall at a load factor of 2.5–3G. 

The ATSB could not determine the stall warning system settings, or if an audible stall warning would have been activated prior to the stall event. However, the stall occurred in a steep turn at a height that was insufficient for recovery.

Knowledge deficiencies

Shortly after the accident, the ATSB was contacted by an AFT instructor who was a colleague of the accident pilot. They advised being unaware of the effect of angle of bank and load factor on stall speed. The accident pilot was trained at the same flight training school (FTS) as the reporting pilot for their recreational pilot certificate (RPC) and instructor rating, prompting an examination of the accident pilot’s knowledge of aerodynamics. 

On review of the accident pilot’s last RAAus exam, the ATSB found that they failed the exam on 2 consecutive attempts. On the pilot’s second attempt, the incorrect answers included 2 questions about stalling, one of which included the relationship between angle of bank, load factor and stall speed. While the pilot’s answer had the correct stall speed for the nominated angle of bank, they had the incorrect load factor. However, it is the load factor generated by manoeuvring flight that affects the stall speed and not the angle of bank. Therefore, the pilot was missing the critical link in the relationship – how the load factor is derived from the angle of bank in a level turn, and how the stall speed is derived from that load factor.

The pilot’s incorrect answers resulted in RAAus expressing their concern about the pilot’s knowledge of aerodynamic stalling when they notified the AFT chief flying instructor (CFI) of the result. The question about load factor and stall speed in a turn was listed in the RAAus syllabus of flight as an item that required a thorough understanding at the RPC level and the exam had been submitted for the pilot’s upgrade from instructor to senior instructor. As the pilot had failed this exam twice, a new exam was required to be completed, and the pilot started a CASA commercial pilot licence theory course. 

From early June to early July 2024, the pilot conducted flight training in a Pitts Special aerobatic aircraft. Several parties reported to the ATSB that this was for the purpose of an aerobatics endorsement. The syllabus for an aerobatics endorsement included the effect of load factor on stall speed. However, the flight training records indicated it was transition training and not training for an aerobatics endorsement. While an aerobatics endorsement included a list of underpinning knowledge requirements, which included the relationship between load factor and stall speed, it was not required to be taught for transition training.

In late July, the pilot failed their first attempt at the CASA commercial pilot licence aerodynamics exam, which included an incorrect answer to the effect of manoeuvring on stall speed. This indicated the pilot’s previous misunderstanding of this topic had not been corrected. However, only the knowledge deficiency reports were retrievable by CASA and not the exam questions and answers, which limited the analysis of these exams. A comparison of the 2 subjects the pilot completed revealed they achieved a high pass result for aircraft general knowledge, but a fail result followed by a low pass result for aerodynamics. This indicated that the pilot found learning the aerodynamic aspects of flight challenging, which was consistent with the concerns previously expressed by RAAus.

The RAAus syllabus for an instructor included demonstrating a stall entry at greater than 1G (critical angle of attack is exceeded at a higher airspeed), which could have addressed the misunderstandings that the pilot held from their RPC theory. While the AFT CFI reported that this training was conducted, the 2 AFT instructors interviewed by the ATSB reported that it was not done and the ATSB found no comments in any of the AFT instructor training records to indicate that it was completed. Therefore, the ATSB concluded that it likely was not done and that the pilot’s knowledge of the relationship between load factor and stall speed was likely deficient at the time of the accident, which contributed to them manoeuvring the aircraft close to the stall speed. 

Pilot flying history and aircraft characteristics

The ATSB interviewed several pilots from AFT who were either colleagues of the accident pilot (fellow instructors) or were RPC graduates from the FTS. They all had experience flying with the accident pilot and 2 of them were syndicate members with the pilot in the purchase of the accident aircraft. One of the syndicate members reported they did not experience any risky flying practices with the pilot but was aware that the pilot had received counselling for such flying.

The ATSB identified that several people, including pilots, fellow instructors and CFIs had been counselling the pilot leading up to the accident, including 3 counselling sessions in the 2 months prior to the accident.

In between the counselling sessions in the last 2 months, there were 3 reported instances of risky flying activities by the pilot. It was therefore likely that no individual involved in counselling the pilot had full knowledge of their behaviour and the counselling sessions did not achieve their intended purpose.

While the safety concerns were discussed with the pilot, no reports were submitted to RAAus and therefore no official action was ever taken. It is possible that there was a reluctance to submit official reports after providing counselling, as this action could make the reporter identifiable and result in a loss of trust between the reporter and their community.  

Two fellow AFT instructors each had experiences with the pilot conducting low level steep turns at high and low speeds and had both advocated to the pilot to manoeuvre their aircraft less aggressively. One of the RPC graduates also experienced the pilot manoeuvring the aircraft aggressively during their pre-RPC check flight in 2023 and conducting a slow speed steep turn overhead a tractor during a private flight in November 2024, 15 days prior to the accident. These reports related to RAAus Topaz and Jabiru aircraft, which both had higher published stall speeds than the Morgan Cougar aircraft. This likely led to an expectation by the pilot that similar manoeuvres could be safely conducted in the Morgan Cougar.

The Morgan Cougar was an amateur-built experimental certificate aircraft, which was subject to a 40-hour flight testing period that included stall testing. However, the stall testing was predominantly limited to 1G clean and configured stalls. The builder was able to recollect one instance of a left turn stall at 30° angle of bank. In this case, the aircraft stalled in a sudden and unexpected manner compared with the 1G stall response, and the builder hypothesised that a stall at a greater angle of bank could exaggerate this effect.

The description provided by the builder was consistent with the warning from the United States (US) Federal Aviation Administration (FAA) that there are no rules for the stall behaviour of an experimental aircraft, and that they can depart controlled flight dramatically without any perceptible warning.

The designer of the Morgan Cougar recommended the builder not attempt accelerated stall testing alone, and this was not done, so the responsiveness of the aircraft to this scenario was unknown. However, the accident pilot invited an AFT RPC graduate for a familiarisation flight in the Morgan Cougar 3 days prior to the accident flight, which the passenger described to the ATSB as for the purpose of demonstrating the responsiveness of the aircraft. During the flight, the pilot demonstrated manoeuvring the aircraft at 70–75° angle of bank, which the passenger described as ‘knife-edge stuff’ and would have required a load factor in the region of 3–4G.

According to the FAA, aircraft with light control forces and/or rapid response are susceptible to overcontrolling by pilots who have not received any type-specific training. Furthermore, low wing aircraft tend to roll into the turn during a turning stall. A stall in a turn will increase the height loss during recovery, as the recovery requires a rolling motion followed by a pitching motion, and therefore, the further the aircraft has to be rolled to restore wings level flight, the greater the height loss.

The syndicate members signed the sale agreement on 5 November, 11 days prior to the accident. However, the builder was unable to accompany them on any familiarisation flights and did not discuss the turning stall behaviour of the aircraft with them. Furthermore, it was concluded from interviews and review of ADS-B data that none of the members had completed any transition training on the aircraft. Therefore, it was very unlikely that the pilot was aware of the specific response of the aircraft in a turning and/or accelerated stall scenario, which was very likely different to the 1G stall and different to the approach to stall and post-stall response of aircraft the pilot had delivered RPC training in at AFT. 

Adventure Flight Training school management

Demonstration of stall at greater than 1G

The RAAus instructor syllabus module for aerodynamic stalling included a stall entry at greater than 1G sequence. This was for the instructor candidate to demonstrate exceeding the aircraft’s critical angle of attack at a higher speed than the 1G stall speed. While this was not part of the RPC syllabus, the instructor syllabus required the demonstration to be performed by the instructor to a high degree of accuracy. However, the AFT instructors interviewed by the ATSB reported that this manoeuvre was not taught on their instructor course and their training records did not include any instructor comments to indicate that it had been completed.

The AFT CFI reported that the stall entry at greater than 1G was taught as a turning stall manoeuvre but could not recall any of the performance parameters for it. Furthermore, the AFT records indicated that a competency code was routinely assigned to their RPC candidates for this manoeuvre as part of their stalling training. Once again, there were no comments within the instructor remarks to indicate that it was taught to those members who had a competency code assigned.

Based on this evidence, the ATSB concluded that this competency was likely not taught at AFT and that the competency code was probably misunderstood.

Instructor supervision

Within the RAAus FTS system, instructors required direct supervision from either their CFI or an approved senior instructor. The purpose of this was to provide continuing mentoring and development of the FTS instructors. The level of supervision could be reduced to indirect (remote) for a senior instructor. However, except for the CFI, none of the AFT instructional staff had progressed to senior instructor. The accident pilot attempted to upgrade to senior instructor in early 2024 but failed the required theory exam component.

When RAAus communicated the pilot’s exam result to the AFT CFI on 29 February 2024, they included their concern about the pilot’s knowledge of aerodynamic stalling and the requirement that the pilot remain under direct supervision. However, the AFT instructors reported to the ATSB that their CFI left the FTS for a trip around Australia in early 2024, with occasional return visits. This was supported by another CFI who had been asked, but declined, to supervise the FTS by the AFT CFI in their absence.

RAAus reported to the ATSB that they were not aware of the AFT CFI’s extended absence from their FTS.

Consequently, the AFT instructors were not under direct supervision for the majority of 2024, even though they had all only received their instructor ratings in 2023. Of note, the instructor who had qualified first, in early 2023, reported to the ATSB that they were all relatively inexperienced as instructors and they did not always conduct a check flight with the CFI during their return visits. This was supported by the accident pilot’s logbook, in which there were no check flights with the AFT CFI recorded in 2024. The fact that the AFT CFI had asked an external CFI to supervise the FTS indicated they were aware of their supervision requirements but ultimately did not comply with them.

Pre-flight video briefings

The RPC graduates from AFT Moama in 2023 and 2024 reported that they did not receive any classroom tutorials or in-person pre-flight briefs. Instead, they had to pay a subscription fee to access a series of flight training videos in which the CFI demonstrated the manoeuvres to be flown for each element of the RPC syllabus. While the CFI stated that the videos were not the pre-flight briefing, the AFT instructors reported that they represented the entirety of the pre-flight briefing, with no in-person pre-flight briefs delivered. 

The use of this medium was not prohibited by the RAAus Exposition, but RAAus had not reviewed the material and therefore had no knowledge of the adequacy of instruction presented. Two RAAus CFIs who had reviewed the videos reported that the quality of instruction in these videos was inadequate as the sole source of pre-flight briefing material.

Within the video sequence for stalling, the AFT CFI demonstrated large rudder inputs near the stall speed and instructed the use of the rudder to level the attitude if a wing drop occurred. The risk of inducing a spin, as described in the CASA flight instructor manual for aeroplanes, was not acknowledged.

Additionally, during the stall demonstrations, the CFI omitted flap limiting speeds for the configured stall and did not demonstrate post-loss of control checks to confirm there was no overspeed or overstress of the flap. If flap is subjected to damage from an overspeed or overstress, further damage and control problems can occur if an attempt is made to retract the flap. In the case of an aircraft with a retractable landing gear, the landing gear could become stuck if an attempt to retract it is made after overspeed damage has occurred.

The stalling video also revealed incorrect terminology by the CFI for their explanation of the effect of lowering flap. This related to the basic lift formula, which should have been taught and reinforced throughout the syllabus. 

While all these discrepancies may have been low risk in the demonstration aircraft, they introduced the potential for negative learning[12] in the lesson, which could be later applied in other aircraft types. The report from one of the AFT instructors, that they believed the accident pilot had copied the CFI in performing dumbbell reversal turns upwind in the circuit to expedite practice landings with students, indicated that negative learning was likely occurring at AFT. 

A component of the instructor assessment was the in-person delivery of a pre-flight brief and post-flight debrief. However, this was not practiced by the staff at Moama after they passed their instructor rating because of the use of pre-flight video. The Moama RPC graduates reported that the lack of access to in-person tutorials and pre-flight briefs contributed to learning difficulties for their flight training and theory exams. The delivery of pre-flight briefs is also important for instructor development because the practice requires them to explain how the theory of flight will be applied in the lesson, check their student’s knowledge, and answer impromptu questions about the topic. It is also the time to discuss any hazards associated with the flight and ensure the student and instructor have a shared understanding of how the lesson will be conducted.

The report from one of the instructors after the accident that they were not aware of the relationship between angle of bank, load factor and stall speed, which is part of the RPC syllabus, may have been the result of knowledge decay because they were not required to deliver briefings. The substitution of video briefs for in-person pre-flight briefs was likely at the expense of both student and instructor development.

Online exams

The AFT CFI introduced an online exam platform used at the Moama Airfield school, for which their students and staff were provided with a login. The ATSB discussed the use of online exams with an instructor and RPC graduate who completed their exams at Riddell Airfield, and they both reported they followed the RAAus paper-based exam process and had no knowledge of the online platform.

The RPC graduates from Moama were prompted by the CFI or staff when they needed to complete a theory exam, which was done online and without supervision. The CFI setup the exams so that 2 attempts could be made and the correct answers to all questions were revealed in the exam report after the first attempt. Consequently, one of the graduates who failed the basic aeronautical knowledge exam on their first attempt photographed all the questions with the correct answers identified and passed the exam on their second attempt. More generally, the online exam setup likely created an attitude from the staff at AFT that candidates would naturally pass the exam on a second attempt if needed. Significantly, there were no failure results from 146 exams in the AFT exam records over a 3-year period.

The accident pilot’s first attempt at the RAAus private pilot licence (aeroplane) (PPL(A)) equivalent exam was completed using the AFT online platform. The software provider had informed the CFI that answer ‘A’ was set as the default correct answer to all questions as they were not provided with the marking rubric. The pilot had used this platform previously for their instructor exam in May 2023 and, given that the other instructor from Moama was aware of how the system was setup, it was very likely that the pilot was also aware of the settings. Consequently, the pilot’s selection of answer ‘A’ to 47/50 questions, the majority of which were technically incorrect, indicated that they were answering to the marking system and not the questions. 

The pilot’s selection of answers may have resulted from the exam report providing the correct answers after a failed first attempt or from the CFI informing the pilot of the default correct response. In either case, the CFI reported that as the administrator, they were the only person who could download a copy of the exam. Therefore, they would have known the result for the exam they submitted to RAAus was almost certainly incorrect based on the default marking. 

Recreational Aviation Australia examination system

The RAAus Exposition, approved by CASA under CASR Part 149, provided a basic overview of their examination system. Multiple-choice exams were provided and the FTSs were to store them securely and not reproduce or distribute them. The exams were distributed to the FTSs via email after each respective CFI had signed a declaration that the exams would be stored securely and not be reproduced or distributed. Candidates for theory exams were provided with an exam answer sheet on which they recorded their answer to each question. All exams were required to be supervised, marked, debriefed and the results recorded and retained by the FTS, with the exception that the RAAus PPL(A)-equivalent exam was to be marked by RAAus. There was no documented exam failure management process.

The RAAus instructor application form indicated that the upgrade to senior instructor was the only time that proof of successful exam completion was required to be provided, which was a change introduced in 2023. Prior to 2023, RAAus did not require proof of completion of any exams for the issue of a qualification or endorsement. In each case they accepted the certification from the examiner that the theory component was met. However, this did not necessarily confirm the examiner had sighted the exam and their certification could be based on the record of result provided by the FTS. The RAAus Exposition required the FTSs to be able to provide exam results on request and RAAus reported that it was the record of exam results that they inspected at audit and not the exam answer sheets. 

Consequently, the AFT CFI was able to progress through their instructor and senior instructor upgrade to CFI approval and the establishment of the AFT FTS, all without providing proof to RAAus that they had completed the associated theory exams. After the FTS was established, the CFI setup a system for online exams that could be completed by AFT members as open-book assessments without supervision. Further, all correct answers were revealed after the first attempt, and the exam could be immediately retaken. This non-compliant system likely existed throughout 2023, unnoticed by RAAus, as AFT’s use of an online platform only came to their attention in January 2024. The accident pilot had used the platform for their instructor exam in May 2023, but proof of completion of the instructor exam was not required to be provided to RAAus. 

The CFI’s upgrade to senior instructor was investigated by RAAus in early 2024 after they discovered the accident pilot’s PPL(A)-equivalent exam failure. They were unable to confirm with the examiner for the CFI’s senior instructor upgrade that the associated exam was done. The setup of the AFT online exam system, and the CFI’s subsequent submission of an exam and certification of remote supervision by a former instructor 2 days after the exam was submitted, all suggested a cultural malaise towards the theory examination requirements. 

The ATSB’s review of the RAAus examination system and the situation that unfolded at AFT, indicated that the only risk control evident in the theory examination system was the CFI declaration to not reproduce or distribute exams. The only effective oversight of exams by RAAus was the marking of the PPL(A)-equivalent exam, as the other oversight activities appeared to be limited to the records of exam results. 

The situation at RAAus contrasted with the CASA examination system, which had multiple controls in place for the access to and conduct of exams, supported by surveillance of the examination centres, which could be unannounced. CASA also had restrictions in place for the exams that could be hosted by an FTS, such that a candidate for an instructor rating would have to conduct some of their theory exams at an examination centre independent of their FTS. 

In 2025, there were a significant number of RAAus FTSs and members, estimated at 160 and 10,000+ respectively based on information from their website. This presented a significant risk management challenge for the integrity of their pilot examination system, particularly noting that their pilots could use their RPC to obtain a CASA licence. Considering the size and complexity of their operation, and what unfolded at AFT as described previously, the ATSB concluded that the RAAus examination system, as described in their Exposition, did not include sufficient controls to prevent the system from being exploited.

Restraint failure

The front seat occupants were ejected from their seats in the accident and the ATSB found the seatbelt latch plates separated from their buckles. However, no evidence was found to indicate the seatbelts were susceptible to false latching, and they were subjected to load testing by the builder. Other mechanisms by which a car seatbelt can fail to perform its function include inadvertent unlatching from occupant flailing in an accident and inertial unlatching. Inertial unlatching is a known phenomenon with car seatbelts in rollover accidents, when they are subjected to vertical accelerations.

The CASA advisory circular guidance for amateur-built experimental certificate aircraft (AC 21.4(2)) recommended that seatbelts comply with the US FAA Technical Standard Order approval for seatbelts. However, the builder did not believe they complied with the recommended standard and that the design was consistent with car seatbelts.

The ATSB reviewed pre-accident photographs of the interior of the aircraft and found the design of the seatbelts was consistent with car seatbelts and inconsistent with aircraft seatbelts. While the release of the front seatbelts would have contributed to the injuries sustained by the front seat occupants, the fatal injuries were likely the result of the ground impact.

Aircraft design and guidance

Energy attenuation

The pathologist reported that all occupants experienced non-survivable, blunt-force trauma injuries. However, the front seat occupants had a common vertebral crushing injury that was not found on the rear seat occupant. A likely source of the discrepancy between the front and rear seat occupant injuries was the location of the front seats above the main wing spar, as per the original design.

There are different mechanisms in which energy attenuation can be incorporated into design, but light aircraft are generally limited to the landing gear and seating. Poorly designed seats can produce spinal fractures in ground impacts as low as 8–10 G. In this situation, an unyielding structure, such as a main wing spar, can transmit a force to the occupant of the seat in excess of the ground impact force and the occupant will suffer injuries greater than those expected from the impact. 

Neither the landing gear nor seating of the accident aircraft appeared to include consideration of crashworthiness in the design. The landing gear separated at impact and did not incorporate any stroking mechanism to absorb vertical energy, and the seating did not incorporate energy attenuation into the design. These 2 design deficiencies contributed to the severity of injuries to the occupants. However, the injuries indicated a minimum force experienced by the occupants and not the actual force they experienced. Therefore, it could not be concluded if a design change would have reduced the forces experienced to a survivable level. Despite that, the ATSB noted that similar accident scenarios in type-certified aircraft have been survivable.

Energy attenuating seat designs, such as stroking mechanisms, deforming box structures and rate-sensitive seat bottom cushions can all play a role in reducing the lumbar load experienced by the occupant in an accident. While there is no requirement for amateur-built aircraft to address this issue, it may be feasible for energy absorbing features to be incorporated into the design of some aircraft. 

The CASA advisory circular guidance for amateur-built experimental certificate aircraft (AC 21.4(2)) recommended the delethalization of the cockpit and installing approved seatbelts but was silent on the issue of energy attenuation for the landing gear and seating. However, a 2013 ATSB aviation research report on amateur-built aircraft accidents found they resulted in a higher rate of fatal and serious injuries than factory‑built and certified aircraft. This indicated that the amateur-built industry could benefit from additional guidance in this area. However, as the CASA AC is guidance material and the recommendations may not be practicable for all builders to implement, it has not been raised as a safety issue. 

Crashworthiness of the fuel system

The pathologist’s examination of the pilot indicated they were deceased prior to the post‑crash fire. However, the wreckage examination revealed a near total destruction of the cabin area by fire, while the extremities of the aircraft were relatively undamaged by fire. This was despite the collision occurring in a relatively level attitude in an open paddock with no penetrating objects. 

The main fuel tank was carrying the flight fuel, and it was installed between the instrument panel and the engine firewall, as designed. This made it susceptible to rupturing in a collision and spraying fuel over the engine and occupants, which occurred in the accident. However, the wing fuel tanks installed aft of the main spar, which were a builder modification, were found intact and provided greater separation of the fuel load from the engine and occupants than the main tank. 

The susceptibility of fuel tanks to rupturing in an accident is not new and there have been published recommended design standards to address this for light aircraft since at least 1980 (Johnson et al. 1980 and 1989). They included guidance for the location of fuel tanks, which should consider the location of occupants, ignition sources and probable impact areas. They recommended fuel tanks be located such that as much aircraft structure as possible can crush before the tanks are exposed to direct contact with obstructions.  

The CASA advisory circular guidance for amateur-built experimental certificate aircraft (AC 21.4(2)) recommended reducing the risk of fire hazard. However, the specific design recommendations were limited to the inclusion of a fireproof firewall between the engine compartment and the cabin. It did not recommend or discuss how to incorporate crashworthiness into the design of the fuel system, and specifically the considerations for the location of fuel tanks. 

Given the susceptibility of aircraft fuel tanks to rupturing and the detrimental effect that it can have on post-crash survival, the ATSB concluded that the amateur-built industry could benefit from additional guidance in this area. However, as discussed previously, the CASA AC for amateur-built experimental certificate aircraft is guidance material and the recommendations may not be practicable for all builders to implement. Therefore, it has not been raised as a safety issue.

Transition training guidance

The accident pilot was a member of a syndicate of 3 pilots who purchased the aircraft on 5 November 2024, 11 days before the accident. While the pilot and another member of the syndicate held instructor ratings, they were for RAAus-registered aircraft, which were 2‑seat aircraft with a maximum take‑off weight of 600 kg. The accident aircraft was a 4‑seat amateur-built experimental certificate aircraft on the CASA register with a maximum take‑off weight of 800 kg.

None of the syndicate pilots were qualified to instruct on this aircraft and none of them met the minimum licence requirements to conduct Phase 1 flight testing, which required a PPL(A) as a minimum. However, they could pilot the aircraft with an RPL as the Phase 1 flight testing of the aircraft was completed by the builder before they purchased it.

In the 11 days after the syndicate purchased the aircraft, ADS-B data recorded 7.7 hours of flying, the majority of which were ferry flights. While the accident pilot likely did most of the flying in the aircraft, the other syndicate members reported that it was unlikely that any aerial work training flights were conducted. One of the syndicate members was concerned about the weight and balance of the aircraft and they had agreed not to conduct any verification flights before the aircraft could be reweighed, which occurred 2 days prior to the accident. In addition, the builder had not conducted any familiarisation flights with them and had not recommended any aerial work exercises for them. Therefore, the ATSB concluded that the pilot had not received any transition training in the aircraft.

A 2013 ATSB aviation research report on amateur-built aircraft accidents found the pilots involved in accidents were significantly more experienced overall than factory-built aircraft accident pilots. However, they were significantly less experienced on the aircraft type that they were flying at the time of the accident, and a quarter of the accidents were from loss of control. 

Previously, in 2012, the US National Transportation Safety Board published a report, which found that pilots who did not seek training for their experimental amateur-built aircraft were overrepresented in accidents. They reported that accidents involving loss of control could be reduced with transition training, which led to a recommendation to the FAA to develop resources for transition training and encourage builders and new owners to complete the training.

The FAA published AC 90-109(A) Transition to unfamiliar aircraft, in 2015. The AC stated that ‘accidents resulting from loss of aircraft control or situational awareness frequently result from pilot unpreparedness for challenges presented by the aircraft’ and provided recommendations for training experience based on aircraft performance and handling characteristics. The AC included an extensive discussion about the variety of stall characteristics that amateur-built aircraft can exhibit and recommended stall avoidance and recovery training from a qualified instructor. 

The FAA AC included a ‘Best Training’ recommendation, which is accomplished in the specific aircraft the pilot intends to fly with a qualified instructor who has recent experience in the same make and model. The accident pilot had previously conducted transition training on the Pitts Special aircraft with an instructor who also had experience with the Morgan Cougar Mk 1 aircraft. Therefore, the ‘best training’ model recommended by the FAA in their AC was an option the syndicate could have pursued.

The CASA advisory circular guidance for amateur-built experimental certificate aircraft (AC 21.4(2)), included recommended safety precautions for the flight-testing phase, which emphasised a graduated process. The purpose of this was for the pilot to learn the behaviour of the aircraft near the centre of the flight envelope before pushing the aircraft out towards the predicted boundary of the envelope. As stated in the AC, ‘Violent or aerobatic manoeuvres should not be attempted until sufficient flight experience has been gained to establish that the aircraft is satisfactorily controllable throughout its normal range of speeds and manoeuvres.’ Despite these recommended precautions for pilots in the flight-testing phase, there were no recommendations for new owners to seek transition training or for sellers to recommend buyers conduct transition training.

The recommended precautionary approach to the flight testing in Phase 1 could equally apply to a new owner of an amateur-built experimental certificate aircraft. Therefore, the ATSB concluded that the amateur-built industry could benefit from further guidance in this area. However, the CASA AC for amateur-built experimental certificate aircraft is guidance material, which may not be practicable to follow in all circumstances, such as a single-seat unique design aircraft. Therefore, it has not been raised as a safety issue.

Civil Aviation Safety Authority management of suspension notices

An individual must be a member of RAAus to exercise the privileges of their RPC. Pilots can then use their RPC, issued by RAAus, to obtain a CASA-issued RPL without completing either a CASA pilot exam or flight test, although a CASA flight review was required to exercise the privileges of the RPL. RAAus is an approved self-administering aviation organisation under Civil Aviation Safety Regulation (CASR) 149, which imposes reporting requirements to CASA under CASR 149.425. The reporting line is from RAAus to the CASA Sport and Recreation Aviation Branch (CASA Sport).

The RAAus mandatory reporting requirements to CASA are detailed in their Exposition, specifically in their occurrence and complaints handling manual (OCHM) under the Formal Inquiry process. However, the RAAus Exposition has a safety related suspension (SRS) notice as a risk management tool within the Informal Assessment process. As the SRS sits within the Informal Assessment process, and is not enforcement action, it does not require notification to CASA. However, RAAus, at their own discretion, can notify CASA that they have issued an SRS where they believe the circumstances warrant such notification. 

In August 2024, RAAus elected to notify CASA of the SRS issued against the AFT CFI because of the position the person held within RAAus. In December 2024, they notified CASA that an SRS was issued against the graduates of AFT because of the number of pilot certificate holders involved. However, the accident pilot had never been issued with an SRS despite their previous exam failures and flying history, and therefore, there was never any cause for CASA to receive a notification about the pilot.

On receipt of the RAAus AFT SRS notifications, CASA Sport entered the details into the CASA records management system, but no further action was taken. CASA had a process for follow-up of notifications, which was their Coordinated Enforcement Process (CEP), detailed in their enforcement manual. Within the CEP an investigator could be appointed to make preliminary enquiries and report findings to the Coordinated Enforcement Meeting for consideration. 

After the ATSB received the details of the persons affected by the SRS issued to the graduates of AFT and their CASA licence status, it was found that 2 members also held RPLs at the time their SRSs were issued. In both cases, their RPL was granted based on their RPC which was subsequently suspended by the SRS. The ATSB spoke to one of those individuals, who reported that nobody from CASA had contacted them, but they had acted immediately to complete the remedial actions to have their SRS lifted. However, the second individual’s membership with RAAus had lapsed and they had not had their SRS lifted when the ATSB received the list of affected persons about 7 months after the SRSs were issued. RAAus confirmed that in this case the individual’s membership profile is flagged to address the remedial action if they re-activate their membership and that there were no continuing reporting requirements to CASA beyond the initial notification.

Consequently, an individual could continue to exercise the privileges of a licence issued by CASA based on holding an RPC while their RPC was suspended. This revealed a missing link within CASA’s internal process for handling the notification of an SRS, with no mechanism in place to ensure CASA Sport forwarded relevant information from the SRS to the CASA CEP for review.

Findings

From the evidence available, the following findings are made with respect to the loss of control and collision with terrain involving a Morgan Cougar Mk1 aircraft, registered VH‑LDV, 19 km NNW from West Sale Airport, Victoria, on 16 November 2024. 

Contributing factors

• The aircraft entered an accelerated stall in a steep turn with insufficient height to recover, resulting in a collision with terrain.
• It was likely that the pilot had an inadequate understanding of the relationship between angle of bank, load factor and stall speed, which contributed to the pilot not fully understanding the risk of conducting slow steep turns.
• The pilot had a reported history of conducting low flying and slow steep turns and was likely unaware that, while the accelerated stall characteristics of the accident aircraft were unknown, there were indications that it would be abrupt.
• The Adventure Flight Training school management practices did not provide the required level of supervision, training and assurance that their graduates had achieved the required level of aeronautical knowledge and understanding for the qualifications they received. (Safety issue)
• The Recreational Aviation Australia pilot theory examination system did not incorporate sufficient risk controls to ensure that their examination processes were followed as intended and their members had achieved the minimum required knowledge in accordance with the syllabus of flight training. (Safety issue)

Other factors that increased risk

• The pilot was counselled about unsafe flying practices but was not reported to any authority and therefore no official follow-up action was ever initiated.
• The aircraft design did not incorporate energy attenuation in the landing gear and seating and located the fuel tank between the engine firewall and instrument panel, which resulted in a post-crash fire. While these factors increased the severity of the injuries to the occupants, it could not be determined if design changes would have made them non-fatal.
• The aircraft’s front seats were likely fitted with car seatbelts, which unlatched in the accident and resulted in the front seat occupants being ejected from their seats. While this exposed them to additional injuries, the fatal injuries were likely from the aircraft‑ground impact.
• The Civil Aviation Safety Authority guidance material for amateur-built experimental aircraft did not recommend consideration of the crashworthiness of seating and fuel tank installation. These characteristics within the design of the aircraft increased the risk of occupant injuries in an accident.
• The pilot had not conducted transition training and the Civil Aviation Safety Authority guidance material for amateur-built experimental aircraft did not include a recommendation for new owners to receive transition training.
• The Civil Aviation Safety Authority (CASA) Sport and Recreation Aviation Branch did not have a process in place to verify if individuals subject to a suspension from a self-administering organisation held a CASA licence and to ensure the information was provided to the CASA Coordinated Enforcement Process for review. (Safety issue)

Safety issues and actions

Adventure Flight Training school management

Safety issue number: AO-2024-058-SI-01

Safety issue description: The Adventure Flight Training school management practices did not provide the required level of supervision, training and assurance that their graduates had achieved the required level of aeronautical knowledge and understanding for the qualifications they received.

Recreational Aviation Australia examination system

Safety issue number: AO-2024-058-SI-02

Safety issue description: The Recreational Aviation Australia pilot theory examination system did not incorporate sufficient risk controls to ensure that their examination processes were followed as intended and their members had achieved the minimum required knowledge in accordance with the syllabus of flight training.

Civil Aviation Safety Authority management of suspension notices

Safety issue number: AO-2024-058-SI-03

Safety issue description: The Civil Aviation Safety Authority (CASA) Sport and Recreation Aviation Branch did not have a process in place to verify if individuals subject to a suspension from a self‑administering organisation held a CASA licence and to ensure the information was provided to the CASA Coordinated Enforcement Process for review.

Safety action not associated with an identified safety issue

Additional safety action by Recreational Aviation Australia

• The draft rewrite of the Recreational Aviation Australia (RAAus) occurrence and complaints handling manual (OCHM) has been updated to include a description of the process for handling a safety related suspension (SRS) for an individual whose membership has lapsed.
• The draft rewrite of the Recreational Aviation Australia (RAAus) syllabus of flight training has been updated to include further development of the stalling element of the syllabus.

Glossary

Sources and submissions

Sources of information

The sources of information during the investigation included:

• accident witnesses
• the aircraft builder
• Airservices Australia
• Bureau of Meteorology
• chief flying instructors from Recreational Aviation Australia
• Civil Aviation Safety Authority
• the former chief flying instructor from Adventure Flight Training
• former instructors and pilot graduates from Adventure Flight Training
• Recreational Aviation Australia
• Victorian Institute of Forensic Medicine
• Victoria Police
• video footage of the accident flight.

References

Australian Transport Safety Bureau (2013) 

(AR-2007-043(2)), accessed 30 May 2025.

Civil Aviation Safety Authority (2000) Amateur-built experimental aircraft – certification (Advisory Circular 21.4(2)), accessed 13 May 2025.

Civil Aviation Safety Authority (2007) Flight instructor manual: aeroplane, accessed 26 March 2025.

Civil Aviation Safety Authority (2022) Experimental certificates (Advisory Circular 21-10 v4.3), accessed 13 May 2025.

Federal Aviation Administration (1986) Static strength substantiation of attachment points for occupant restraint system installations (Advisory Circular 23-4), accessed 24 June 2025.

Federal Aviation Administration (1993) Technical Standard Order: C22g, safety belts (TSO C22g), accessed 24 June 2025.

Federal Aviation Administration (2015) Amateur-built aircraft and ultralight flight testing handbook (Advisory Circular AC 90-89B), accessed 20 May 2025.

Federal Aviation Administration (2015) Transition to unfamiliar aircraft(Advisory Circular 90-109(A)), accessed 3 July 2025.

Society of Automotive Engineers (1986) Aerospace standards: Torso restraint systems (SAE AS 8043), accessed 24 June 2025.

Taylor AM and Moorcroft DM (2023) Seat and occupant response in energy absorbing seats (Civil Aerospace Medical Institute DOT/FAA/AM-23/17), accessed 22 May 2025.

Gratton G (2015) Initial airworthiness: determining the acceptability of new airborne systems, Springer, London.

Johnson NB et al. (1989) Aircraft Crash Survival Design Guide Volume V – Aircraft Postcrash Survival (USAAVSCOM TR 89-D-22E), accessed 3 July 2025.

National Transportation Safety Board (2012) The Safety of Experimental Amateur-Built Aircraft (NTSB/SS-12/01), accessed 28 March 2025.

Payne R and Stech E (1969) Dynamic models of the human body (Aerospace Medical Research Laboratory AMRL-TR-66-157), accessed 3 July 2025.

Roberts et al. (2007) ‘Failure analysis of seat belt buckle inertial release’, Engineering failure analysis, 14(6):1135-1143.

Shanahan DF (28-29 October 2004) Basic Principles of Crashworthiness: Pathological Aspects and Associated Biodynamics in Aircraft Accident Investigation. Madrid, Spain: RTO-EN-HFM-113, accessed 3 July 2025.

Submissions

Under section 26 of the Transport Safety Investigation Act 2003, the ATSB may provide a draft report, on a confidential basis, to any person whom the ATSB considers appropriate. That section allows a person receiving a draft report to make submissions to the ATSB about the draft report. 

A draft of this report was provided to the following directly involved parties:

• the aircraft builder
• Civil Aviation Safety Authority
• the former chief flying instructor from Adventure Flight Training
• Recreational Aviation Australia. 

Submissions were received from:

• Civil Aviation Safety Authority
• the former chief flying instructor from Adventure Flight Training
• Recreational Aviation Australia. 

The submissions were reviewed and, where considered appropriate, the text of the report was amended accordingly.

Appendices

Appendix A – Examination of the flight controls

Introduction

Examination of the flight control system chainring and bearings included a photographic review of the chainring at the wreckage site and as installed in the aircraft pre-accident, which was behind the instrument panel (Figure 12). 

Figure 12: Location and movement of chainring

Source: ATSB

The part that transmitted roll control from either yoke to the ailerons consisted of 2 chainrings welded together around a hexagonal nut to form one part, hereafter referred to as the ‘chainring’ (Figure 13). The chainring was supported by an inner and outer bearing attached to a support frame. Two grub screws located in threaded holes through the nut were present to secure the chainring to a bearing. 

Figure 13: Front chainring facing pilot (left) and rear chainring facing engine (right)

Source: ATSB

Examination and findings

It was noted that the chainring hexagonal nut appeared to be centrally located on the bearings (Figure 14 left) before the controls were disturbed for onsite examination and that the chainring only separated from the bearings when it was disturbed. Pre- and post‑accident photographs of the flight controls and measurement of the clearance between the chainring and the support frame indicated that the 2 grub screws could only have engaged with the outer bearing (Figure 14 right). 

Figure 14: Location of bolt relative to hexagonal nut (left) and bearings (right)

Source: ATSB

The examination found that the 2 grub screws were not proud of the hexagonal nut inner diameter (Figure 15 [1, 2]) and they had an angular separation of 117° (Figure 15 [3]). The inner bearing and the outer bearing (Figure 15 [4]) were examined, cleaned and re‑examined. No witness marks from the grub screws were identified. The grub screws (Figure 15 [5, 6]) were examined, cleaned and re-examined and no bearing witness marks were identified. Therefore, ATSB examination could not confirm that the grub screws retained the chainring to either bearing.

Figure 15: Condition of grub screws and outer bearing

Source: ATSB

Appendix B – Flight path description

Introduction

The end-of-flight analysis was divided into sections based on the manoeuvring of the aircraft, which have been annotated on the supporting figures. It started with a right turn, followed by a reversal into a left turn followed by 2 full orbits. A third left orbit commenced inside of the second orbit, which led to the stall and collision with terrain. Airservices Australia ADS-B data was used, and altitudes are recorded in 25 ft increments. The last 3 data points, considered unreliable, were inconsistent with the observed CCTV and were potentially predicted points that were not updated prior to the collision.[13] The calibrated airspeed (CAS) range was calculated by the ATSB using a 6 kt mean wind and 12.8 kt wind gust from 124° T recorded at a local weather station 4 km north of the accident site. 

End of flight description

With reference to Figure 16:

• At the start of the right turn (RH turn – yellow) at 1744:17, the aircraft recorded a groundspeed of 98 kt (87‍–‍91 kt CAS) and an altitude of 825 ft (683 ft AGL). Altitude was maintained through the turn, but groundspeed (and estimated CAS) reduced.
• The first orbit (First orbit – blue) started at 75 kt groundspeed (78‍–‍85 kt CAS) and an altitude of 825 ft (689 ft AGL) and the aircraft descended about 250 ft during the orbit.
• The second orbit (Second orbit – orange) started at 82 kt groundspeed (84‍–‍89 kt CAS) and an altitude of 575 ft (442 ft AGL). During the orbit, the aircraft descended and conducted a low pass (Low pass) at 97 kt groundspeed (89‍–‍92 kt CAS) and an altitude of 225 ft (97 ft AGL).
• A brief straight section (cyan) started at 69 kt groundspeed (72‍–‍79 kt CAS) and an altitude of 400 ft (267 ft AGL) and reduced to 64 kt groundspeed (67‍–‍74 kt CAS) at the start of the final turn (Turn – magenta) at 1746:52.
• In the final turn at 1746:59 (Stall), the groundspeed reached a minimum of 56 kt (59‍–‍65 kt CAS) at an altitude of 350 ft (221 ft AGL) as the turn radius tightened and an average of 45° angle of bank was required for this turn radius.
• The last reliable data point was recorded at 1747:02 and indicated a groundspeed of 71 kt (69 kt CAS) at an altitude of 275 ft (143 ft AGL). The abrupt descent and increase in speed were consistent with a conventional stall response.

In the accompanying Figure 17, the start of the right turn (RH turn), start of the first orbit (First orbit), start of the second orbit (Second orbit), low pass (Low pass), start of the final turn (Turn) and stall (Stall) are annotated. The lowest speeds were recorded on the segment from the final turn to the stall, which was also the segment with the smallest turn radius. 

Figure 16: Accident flight path

Source: Airservices Australia, annotated by the ATSB

Figure 17: Plot of ADS-B data and CAS calculations with the start of each orbit

Source: ATSB

Purpose of safety investigations The objective of a safety investigation is to enhance transport safety. This is done through:  identifying safety issues and facilitating safety action to address those issues providing information about occurrences and their associated safety factors to facilitate learning within the transport industry. It is not a function of the ATSB to apportion blame or provide a means for determining liability. At the same time, an investigation report must include factual material of sufficient weight to support the analysis and findings. At all times the ATSB endeavours to balance the use of material that could imply adverse comment with the need to properly explain what happened, and why, in a fair and unbiased manner. The ATSB does not investigate for the purpose of taking administrative, regulatory or criminal action. About ATSB reports ATSB investigation reports are organised with regard to international standards or instruments, as applicable, and with ATSB procedures and guidelines. Reports must include factual material of sufficient weight to support the analysis and findings. At all times the ATSB endeavours to balance the use of material that could imply adverse comment with the need to properly explain what happened, and why, in a fair and unbiased manner. An explanation of terminology used in ATSB investigation reports is available here. This includes terms such as occurrence, contributing factor, other factor that increased risk, and safety issue. Publishing information Released in accordance with section 25 of the Transport Safety Investigation Act 2003 Published by: Australian Transport Safety Bureau © Commonwealth of Australia 2026   Ownership of intellectual property rights in this publication Unless otherwise noted, copyright (and any other intellectual property rights, if any) in this report publication is owned by the Commonwealth of Australia. Creative Commons licence With the exception of the Commonwealth Coat of Arms, ATSB logo, and photos and graphics in which a third party holds copyright, this report is licensed under a Creative Commons Attribution 4.0 International licence. The CC BY 4.0 licence enables you to distribute, remix, adapt, and build upon our material in any medium or format, so long as attribution is given to the Australian Transport Safety Bureau.  Copyright in material obtained from other agencies, private individuals or organisations, belongs to those agencies, individuals or organisations. Where you wish to use their material, you will need to contact them directly.

Investigation summary

What happened

On the morning of 22 October 2024, the pilot of a Cessna Aircraft Company 150L, registered VH‑EYU, was conducting a private flight from Bacchus Marsh aircraft landing area, Victoria. Strong and gusting winds were present. After commencing a take-off roll, the pilot rejected the take-off, before taxiing back to the same runway for a second take‑off.

On the second take-off, the aircraft became airborne and climbed to about 150 ft above the runway, before it pitched steeply nose-up, then the nose dropped suddenly, followed by the left wing dropping. The aircraft then entered a vertical descent, rotating approximately 270° before colliding with terrain. The pilot, who was the sole occupant of the aircraft, was fatally injured, and the aircraft was destroyed. 

What the ATSB found

The ATSB found that shortly after take-off, in strong and gusty wind conditions, the aircraft stalled at a height too low to recover before colliding with terrain. It is probable that the aircraft was too slow on take-off into those conditions, and that inputs made to counteract the crosswind increased the angle of attack of the left wing. These factors, combined with the wind conditions, increased the risk of a quick and unrecoverable stall.

Safety message

While an aerodynamic stall can occur at any airspeed, at any altitude, and with any engine power setting, it is most hazardous during take-off and landing when the aircraft is close to the ground. When gusting conditions are present, pilots should consider waiting for more benign conditions. Guidance advises pilots to conduct their own testing in progressively higher winds to determine both their own capability and that of the aircraft. 

Maintaining the aircraft’s attitude and correcting any change in attitude due to wind gusts during climb, is vital to ensure the critical angle of attack is not exceeded. Reducing the angle of attack by lowering the aircraft nose at the first indication of a stall is the most important immediate response for stall avoidance and recovery. 

Pilots must understand and recognise the conditions which make stall more likely and the symptoms of an approaching stall so they can act to prevent a stall before an unrecoverable condition develops. If pilots judge the weather to be suitable, they should consider climbing out at a higher airspeed to provide a buffer above their aircraft’s stall speed for detection and correction of an impending stall. 

The investigation

The occurrence

On the morning of 22 October 2024, at the Bacchus Marsh aircraft landing area (ALA), Victoria, a Cessna Aircraft Company 150L aircraft, registered VH‑EYU, was being prepared for a private flight under visual flight rules[1] to Lethbridge ALA, Victoria, about 35 km to the southwest. The weather conditions at the time were described as having strong, variable and gusty winds with a temperature of about 27°C.

Closed circuit television (CCTV) showed the pilot arriving for their flight at about 1000. Later, at about 1047, another CCTV camera located at a flying school, recorded the aircraft taxiing to the fuel bowser. After fuelling, the pilot drained a fuel sample from the aircraft fuel tanks and checked the sample. The pilot, who was the sole occupant, climbed in, then started the aircraft and taxied to a run‑up area[2] and performed engine run-up and flight control checks. They then taxied toward runway 27[3] for take‑off (Figure 1).

At about 1110 local time, a common traffic advisory frequency[4] (CTAF) recording captured the pilot stating that they were commencing their take‑off roll. Shortly after, the pilot transmitted another radio call stating that they were rejecting the take‑off. There was no further information provided by the pilot to explain why the take‑off was rejected. 

The rejected take-off attracted the attention of witnesses who were now observing VH‑EYU. The pilot taxied the aircraft off the runway and returned to the end of runway 27. At 1114, the pilot commenced a second take‑off roll.

The witnesses included a flight instructor. They identified that the aircraft appeared unstable after take-off. The CCTV showed the right wing dipping twice during this take‑off, with the pilot levelling the aircraft each time. The flight instructor stated that at about 50 ft, the aircraft pitched up quickly, before the nose was pushed down again.

After the aircraft had passed the runway intersection and reached an altitude of about 150 ft, it pitched steeply upward, before the nose and then the left wing rapidly dropped. The aircraft entered a nose down vertical descent to the left, rotating approximately 270° before colliding heavily with terrain. After the collision, personnel from the flying school attended the accident site and found the pilot fatally injured. The aircraft was destroyed. 

Figure 1: Bacchus Marsh ALA and VH‑EYU approximate flight path (yellow) and accident site

Source: Google Earth, annotated by the ATSB

Context

Pilot information

The pilot commenced their flight training in July 2019 and held a recreational pilot licence (aeroplane), which was issued on 14 November 2023. They held a single engine aeroplane class rating. The pilot also held navigation, controlled aerodrome, controlled airspace and flight radio endorsements which were issued on 19 April 2024. 

Overall, the pilot had accumulated about 184 hours total aeronautical experience, of which 71.9 hours were in the Cessna 152 and 3.8 hours in the Cessna 150.

The pilot joined Bacchus Marsh Aero Club on 19 August 2024 and had completed 3 club check flights with an independent instructor during September and October 2024. Since joining the club, the pilot had flown a total of 20.1 hours in Cessna 172, Cessna 152 and Cessna 150 aircraft. They had also flown 3.3 hours in a Cessna 152 the previous day. 

The pilot held a Class 2 aviation medical certificate issued by the Civil Aviation Safety Authority, without medical restrictions, which was valid until 19 March 2026.

Post-mortem examination 

The post-mortem and toxicology examinations did not identify any indication of incapacitation or substances that could have affected the pilot’s capacity to perform the flight.

Aircraft information

The Cessna 150L is a high wing, all-metal, 2‑place, single‑engine aircraft with a fixed tricycle landing gear. It is powered by a 4‑cylinder Teledyne‑Continental O‑200‑A engine, driving a 2‑blade fixed‑pitch propeller. VH‑EYU (Figure 2) was manufactured in the United States in 1974 and first registered in Australia in May 1974. It had been owned by the Bacchus Marsh Aero Club since December 2023. 

The aircraft was fitted with a stall warning horn on the left wing, which produces an audible signal to the pilot when the wing is approaching its critical angle of attack (AoA). The Cessna 150L’s stated stall speed in take‑off configuration with wings level was 48 kt.[5]

No crosswind limitation was published in the C150 L model owner’s manual. There was only a need for the manufacturer to demonstrate crosswind capability up to 8.5 kt (20% of the stall speed in a landing configuration). While it is possible that the aircraft may be capable of meeting the controllability standard in higher winds, this had not been established by the manufacturer.

Figure 2: VH-EYU

Source: Bacchus Marsh Aero Club

Recent maintenance history

The last 100‑hour periodic maintenance inspection was conducted on 19 January 2024. At the time of the accident, VH‑EYU had accrued a total time in service of 8,962.3 hours. Maintenance records also showed that since January, the following maintenance had been performed:

• a 50-hour/6-month oil and filter change
• the left brake was serviced
• the flap position indicator spring was replaced.

The aircraft had flown about 36.3 hours since the last scheduled maintenance which was conducted on 21 April 2024. There were no open defects recorded on the maintenance release and no outstanding or overdue maintenance was noted. 

Aerodrome information

Bacchus Marsh aircraft landing area (ALA) was located about 6.5 km south of Bacchus Marsh, Victoria. It consisted of 2 sealed runways, 01/19 in a north‑south direction and 09/27 in the east‑west direction. The ALA was home to the Bacchus Marsh Aero Club, a pilot training school and several gliding clubs, as well as several privately owned aircraft. 

The ALA was in non‑controlled Class G airspace. Aircraft operating in the area did not require clearance and a common traffic advisory frequency (CTAF) was available for pilot‑to‑pilot communication. 

Bacchus Marsh Aero Club

Bacchus Marsh Aero Club operated several single-engine aircraft that were available to hire for approved club members, including the Cessna 150, 152, 172 and 182 models. Due to its status of being a private flying club and to satisfy insurance purposes, the club had a procedure in place for an independent flight instructor to conduct flight checks on new members prior to them being approved to fly club aircraft. 

Site information 

The accident site was in a barley field, 205 m south of the runway 27 centreline and to the west of runway 19/01 (Figure 1). The fuselage was orientated to the north. Ground impact marks were directly under the wreckage indicating no forward momentum. The damage signatures showed that the aircraft had impacted the field in a steep nose down attitude with the initial ground contact at the leading edge of the left wing. Severe disruption of the cockpit area, wing assembly and rear fuselage had occurred from the impact (Figure 3).

Figure 3: VH-EYU at the accident site

Source: ATSB

Wreckage examination

The ATSB’s examination of the wreckage did not identify any evidence of pre‑existing faults, flight control issues or engine issues and there was no evidence of birdstrike. 

All components were accounted for at the accident site. The right fuel tank had ruptured, while the left tank remained intact. A quantity of fuel was removed from the aircraft fuel tank for onsite testing and was found to be clean and clear of contaminants. Fuel was removed from the carburettor, which was also tested with no water or contaminants found.

The wings and centre fuselage roof section had separated and moved forwards as a result of the impact. Portions of the airframe were removed by first responders prior to ATSB examination, and these were photographed prior to removal. The stall warning horn on the left wing was damaged in the accident sequence and could not be tested for functionality. The flaps were noted to be retracted, which is the position required in the normal take‑off checklist. 

An examination of the seat rails showed that the pilot seat was locked into position and had not moved prior to the accident.

The engine and propeller displayed no pre‑existing damage. The engine was externally examined, and all components were accounted for. The engine was able to be rotated which indicated no significant internal damage had occurred. 

The propeller and flange had fractured from the engine crankshaft and there was evidence of rotation on the fracture surfaces. The propeller displayed minor rotational scoring and rearward bending which was indicative of low rotational energy at the time of impact. 

The throttle control in the cockpit was set at a low power position and had been bent upwards during the impact sequence. 

Survival aspects

The pilot had been wearing a lap/sash seat belt during the accident flight. The extent of the damage to the occupiable space of the aircraft cabin meant that the impact was not considered survivable.

Aircraft stall and spin behaviour 

Aerodynamic stalls

An aerodynamic stall is a rapid decrease in lift and increase in drag caused by the separation of airflow from the wing’s upper surface. A stall occurs when the angle of attack^[6] exceeds the wing’s critical angle of attack,^[7] resulting in the disruption to the smooth airflow over the wing. This can ordinarily occur at angles of around 16° (Figure 4). Due to the sudden reduction in lift from the wing and rearward movement of the centre of lift, an uncommanded nose‑down pitch ensues. 

The US Federal Aviation Administration (FAA) Airplane Flying Handbook (2021) states that:

• Impending Stall—an impending stall occurs when the AOA causes a stall warning but has not yet reached the critical AOA. Indications of an impending stall can include buffeting… or aural warning.

• Full Stall—a full stall occurs when the critical AOA is exceeded. Indications of a full stall are typically that an uncommanded nose down pitch cannot be readily arrested and may be accompanied by an uncommanded rolling motion... 

The FAA Airplane Flying Handbook (2021) also states that for an impending stall the pilot should:

…immediately reduce AOA once the stall warning device goes off, if installed, or recognizes other cues such as buffeting. The pilot should hold the nose down control input as required to eliminate the stall warning. Then level the wings maintain coordinated flight, and then apply whatever additional power is necessary to return to the desired flightpath.

Figure 4: Effect of increasing angle of attack leading to a stall condition

Source: CASA AvSafety, annotated by the ATSB

Aerodynamic spins

A spin can result when an aircraft simultaneously stalls and yaws.[8] The yaw can be initiated by rudder application (through manipulation of the rudder pedals) or by yaw effects from a range of factors that include aileron deflection, torque, wind and engine/propeller effects. A spin is characterised by the aircraft following a downward, corkscrew path and requires significantly more altitude for recovery compared to a wings level stall.

The spin recovery procedure stated in the Cessna 150L handbook was:

For recovery from an inadvertent or intentional spin, the following procedure should be used.

• retard the throttle to idle position

• apply full rudder opposite to the direction of rotation

• after one-fourth turn, move the control wheel forward of neutral in a brisk motion

• as rotation stops, neutralize rudder and make a smooth recovery from the resulting dive. 

Application of aileron in the direction of the spin will greatly increase the rotation rate and delay the recovery. Ailerons should be held in a neutral position throughout the spin and the recovery. Intentional spins with flaps extended are prohibited.

To recover from the spin, the pilot requires sufficient height to conduct the procedure and fly away. During the initial stages of a take‑off, there is insufficient height to perform these actions. 

Control input in a crosswind

In a crosswind, to prevent uncommanded roll, the pilot must turn the control yoke into wind. This will move the ailerons to change the relative angle of attack of each wing (Figure 5). The aileron on the into‑wind wing (right in this case) will move up, create a lower angle of attack and produce less lift. The aileron on the downwind wing (left in this case) will move down, creating a higher angle of attack and more lift. Therefore, resisting the rolling moment created by the crosswind.

Figure 5: Effect of aileron use on angle of attack

Source: Flight Safety Australia

Guidance

The FAA Airplane Flying Handbook (2021) states for take‑off in gusty conditions that:

During take-offs in a strong, gusty wind, it is advisable that an extra margin of speed be obtained before the airplane is allowed to leave the ground. A take-off at the normal take-off speed may result in a lack of positive control, or a stall, when the airplane encounters a sudden lull in strong, gusty wind, or other turbulent air currents. In this case, the pilot should allow the airplane to stay on the ground longer to attain more speed, then make a smooth, positive rotation to leave the ground.

A Civil Aviation Safety Authority publication AC 91‑02 v1.2 – Suitable places to take‑off and land, and the FAA publication Personal minimums for wind both identify that is the responsibility of the pilot in command to consider the winds and determine if the aircraft can be operated safely in the prevailing conditions. The FAA publication advises pilots to conduct their own testing in progressively higher winds to determine both their own capability and that of the airframe.

Meteorological information

Forecast weather

The planned flight from Bacchus Marsh to Lethbridge was within the Victoria graphical area forecast (GAF)[9] region. The Bureau of Meteorology issued a GAF which included the Bacchus Marsh area, at 0900 on 22 October 2024, and was valid from 1000‍–‍1600. The forecast indicated visibility greater than 10 km and no cloud. A Grid Point Wind and Temperature Forecast was issued by the Bureau of Meteorology at 0525 on 22 October 2024. No wind and temperature was available in the Bacchus Marsh area below 5,000 ft. 

The Bureau of Meteorology issued aerodrome forecasts (TAF)[10] and meteorological aerodrome reports (METAR)[11] for Melbourne, Essendon, Avalon and Ballarat airports. A special meteorological report (SPECI)[12] was also issued, which highlighted that a significant wind gust had been recorded. 

There was no record that the pilot had used any personal login to access weather forecasts prior to their flight, from any official sources. It is unknown if the pilot had checked a forecast via other sources which did not require accounts for access.

Nearby airport weather

The actual weather at Bacchus Marsh ALA was not recorded and not available. However, forecasts and observation reports were available for nearby airports. Table 1 shows the recorded winds at Melbourne Airport leading up to the accident. Melbourne Airport is about 38 km on a bearing of 78° True (° T) from Bacchus Marsh. 

Table 1: Wind speed and direction recorded at Melbourne Airport

Source: Bureau of Meteorology 

Table 2 shows the recorded winds at Ballarat Airport leading up to the accident. Ballarat Airport is about 59 km on a bearing of 293° T from Bacchus Marsh.

Table 2: Wind speed and direction recorded at Ballarat Airport