Collision with terrain

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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

Time	Temperature (°C)	Wind speed (kt)	Wind gust (kt)	Wind direction (°T)
1745	27.5	6.2	8.0	124
1750	27.3	6.4	12.8	122

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

Bank angle	Load factor (G)	Stall speed (37 kt)	Stall speed (38 kt)	Stall speed (42 kt)
0	1.00	37	38	-
30	1.15	40	41	42
45	1.41	44	45	46
60	2.00	52	54	55
70	2.92	63	65	67
75	3.86	73	75	77

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

Date	Theory exam
31 May 2022	Pre-solo
20 June 2022	Air legislation
29 June 2022	Basic aeronautical knowledge
13 August 2022	Radio
13 August 2022	Human factors
4 December 2022	Navigation theory [includes meteorology theory]
21 May 2023	RAA instructor rating

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.

Contributing factor The aircraft entered an accelerated stall in a steep turn with insufficient height to recover, resulting in a collision with terrain.

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. 

Contributing factor 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.

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.  

Other factor 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.

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. 

Contributing factor 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.

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. 

Contributing factor 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)

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.

Contributing factor 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)

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.

Other factor that increased risk 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.

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.

Other factor that increased risk 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.

Other factor that increased risk 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.

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.

Other factor that increased risk 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.

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.

Other factor that increased risk 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)

Findings

ATSB investigation report findings focus on safety factors (that is, events and conditions that increase risk). Safety factors include ‘contributing factors’ and ‘other factors that increased risk’ (that is, factors that did not meet the definition of a contributing factor for this occurrence but were still considered important to include in the report for the purpose of increasing awareness and enhancing safety). In addition, ‘other findings’ may be included to provide important information about topics other than safety factors.  Safety issues are highlighted in bold to emphasise their importance. A safety issue is a safety factor that (a) can reasonably be regarded as having the potential to adversely affect the safety of future operations, and (b) is a characteristic of an organisation or a system, rather than a characteristic of a specific individual, or characteristic of an operating environment at a specific point in time. These findings should not be read as apportioning blame or liability to any particular organisation or individual.

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

Central to the ATSB’s investigation of transport safety matters is the early identification of safety issues. The ATSB expects relevant organisations will address all safety issues an investigation identifies.  Depending on the level of risk of a safety issue, the extent of corrective action taken by the relevant organisation(s), or the desirability of directing a broad safety message to the aviation industry, the ATSB may issue a formal safety recommendation or safety advisory notice as part of the final report. All of the directly involved parties were invited to provide submissions to this draft report. As part of that process, each organisation was asked to communicate what safety actions, if any, they had carried out or were planning to carry out in relation to each safety issue relevant to their organisation.  Descriptions of each safety issue, and any associated safety recommendations, are detailed below. Click the link to read the full safety issue description, including the issue status and any safety action/s taken. Safety issues and actions are updated on this website when safety issue owners provide further information concerning the implementation of safety action.

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

Whether or not the ATSB identifies safety issues in the course of an investigation, relevant organisations may proactively initiate safety action in order to reduce their safety risk. The ATSB has been advised of the following proactive safety action in response to this occurrence.

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

AC	Advisory circular
ADS-B	Automatic dependent surveillance-broadcast
AGL	Above ground level
AFT	Adventure Flight Training
AMSL	Above mean sea level
CAS	Calibrated airspeed
CASA	Civil Aviation Safety Authority
CASR	Civil Aviation Safety Regulations
CCTV	Closed-circuit television
CEP	Coordinated enforcement process
CFI	Chief flying instructor
FAA	Federal Aviation Administration (United States)
FOM	Flight operations manual
FTS	Flight training school
KDR	Knowledge deficiency report
NTSB	National Transportation Safety Board (United States)
OCHM	Occurrence and complaints handling manual
OCMS	Occurrence and complaints management system
PEXO	Pilot examination office. The CASA online theory examination system.
PI	Performance indicator
POH	Pilot operating handbook
RAAus	Recreational Aviation Australia
RPC	Recreational Pilot Certificate
RPL	Recreational Pilot Licence
SRS	Safety related suspension
US	United States

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 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.

Investigation summary

What happened

On the morning of 26 October 2024, the pilot of a De Havilland Aircraft of Canada DHC‑2 Beaver aircraft, registered VH‑OHU, departed Hamilton Island aerodrome, Queensland, with 4 passengers on board, for a 10-minute scenic flight to Whitehaven Beach, Whitsunday Island. The aircraft touched down on the water with the right main gear not retracted into the float. As a result, the aircraft rapidly yawed to the right, nosed over and became submerged inverted. The pilot self-evacuated and then, when they found no one else on the water surface, promptly returned to help the passengers egress. The pilot and 4 passengers sustained minor injuries, and the aircraft was substantially damaged.

What the ATSB found

The ATSB found that, after departing Hamilton Island, the right main landing gear did not retract and had seized in the extended position, likely due to corrosion. For undetermined reasons, the pilot did not identify that the right main gear had remained extended during their pre-landing checks, either via the landing gear position indication panel, the amphibian gear advisory system (AGAS) annunciation or the wing-mounted mirror. 

In addition, the ATSB noted that the AGAS annunciation alert for an asymmetric configuration, which required immediate pilot action, was similar to a normal gear position advisory. This increased the risk that a pilot would not recognise that the gear was in an unsafe condition for a water landing.

Following the collision with water, and with the aircraft submerged and inverted, the left rear cabin door could not be opened by the pilot or passengers, which delayed their egress. However, the pilot opened the right main door and assisted all passengers to evacuate.

As required by the operator, the pilot had completed helicopter underwater escape training about one month prior to the accident and credited this as a life-saving course.  

Following several floatplane accidents in Canada, the Transportation Safety Board of Canada recommended the fitment of regular and emergency exits that allowed rapid occupant egress following a survivable collision with the water. Viking Air Limited subsequently developed push-out windows and revised more intuitive automotive-style door latches for the rear cabin door on the DHC‑2 aircraft. These modifications were not fitted to VH-OHU nor were they required by regulations. 

What has been done as a result

In response to the accident, Hamilton Island Air advised it has implemented formal initial and refresher training for pilot maintenance tasks, as well as installation of a second mirror on the right wing of its current DHC‑2 aircraft. It has developed a sign-off form to document the daily washdown and preventative maintenance procedures. In addition, it incorporated a minimum weekly systems check flight, including landing gear cycle, where the aircraft had not been recently operated. Further, it introduced annual theory training and 180-day proficiency flight checks, conducted by authorised flight training organisations.

The Civil Aviation Safety Authority has developed airworthiness bulletin AWB 32-029 Issue 1 Supplementary Type Certificated Amphibian Float Main Gear Slide Wear in Marine Environments. The bulletin recommended enhanced vigilance and maintenance actions on the landing gear components to ensure reliability of the landing gear and the actuating system.

Safety message

As shown in this accident, inadvertent water landings in amphibian aircraft with one or more gear extended can rapidly result in the aircraft becoming submerged and inverted. This investigation reinforces the effectiveness of helicopter underwater escape training, not exclusively for helicopter pilots but also for pilots who operate any type of aircraft over water such as floatplanes.

Further, this accident highlights the value of having alternate means of exiting an aircraft post-accident. This is particularly important if the pilot is unable to assist and/or the fuselage is distorted, to increase the occupants’ chance of survival in the event of an impact with water.

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.

The investigation

The ATSB scopes its investigations based on many factors, including the level of safety benefit likely to be obtained from an investigation and the associated resources required. For this occurrence, the ATSB conducted a limited-scope investigation in order to produce a short investigation report, and allow for greater industry awareness of findings that affect safety and potential learning opportunities.

The occurrence

On the morning of 26 October 2024, a De Havilland Aircraft of Canada DHC‑2 Beaver amphibian floatplane, registered VH‑OHU and operated by Whitsunday Air Services (trading as Hamilton Island Air), was being prepared for a scenic flight from Hamilton Island to Whitehaven Beach (Whitehaven), Whitsunday Island, Queensland. The flight would typically be about 10–15 minutes, with about 75 minutes at Whitehaven, before returning to Hamilton Island.

Prior to boarding the aircraft, the 4 passengers viewed a pre-flight safety briefing video and were fitted with a pouch‑style constant wear lifejacket.[1] The pilot then conducted an additional briefing at the rear left cabin door of the aircraft. The passengers recalled this included being demonstrated how to use their seatbelts, don the lifejackets and operate the rear door handle, among other things. The passengers were seated, in pairs, in the middle and rear seat rows, with the seat to the right of the pilot not utilised.

The aircraft departed to the south-east and made a left turn to track toward Chance Bay, Whitsunday Island (Figure 1). The pilot reported that, during initial climb, they set climb power and selected the landing gear to retract (see Landing gear actuation system). The pilot noted the gear was cycling, as evidenced by the illuminated red ‘hydraulic pump’ lamps.  

At about Chance Bay, the pilot spoke with the pilot of a company helicopter that was following, via very high frequency radio transmission, to coordinate with them as they were both heading toward Tongue Point. From this location, the pilot observed the water conditions and location of boats moored along Whitehaven. They described their observation as 7 kt, from the south-east and about 3 or 4 vessels on the water at Whitehaven. They then reported observing 4 blue ‘gear up’ lights on the landing gear panel and they did not see any of the main wheels extended in the mirror mounted on the left wing (see Mirror). The pilot then conducted an orbit over Tongue Point and Hill Inlet, before making a turn and doing a second pass so all passengers could view the beaches and inlets below.

After advising the passengers they would shortly be landing, the pilot commenced the pre-landing cockpit flow checks, including isolating the passengers from the aircraft audio system. The pilot advised they confirmed 4 blue lights, ‘saw no gear visible out the left window’, completed their flow checks and commenced the descent for landing. The pilot broadcast their intent to land at the south end of Whitehaven. They then completed the ‘finals checks’ from memory, which included checking the landing gear position again, before focusing on the landing.

Figure 1: Whitehaven Beach with reference to Hamilton Island, with approximate flight path depicted in yellow

Note: Approximate flight path derived from limited passenger images and video footage. Source: Google Earth, annotated by the ATSB

Upon touching down on the water, the aircraft bounced, then yawed sharply to the right, before nosing over and becoming submerged inverted. With the aircraft quickly filling with water, the pilot released their seatbelt and went to open their door, which they reported required some force. On exiting the aircraft, their leg was caught in the seatbelt, however, they were able to free themselves and swam to the surface. At the same time, 2 of the passengers had released their seatbelts and were both trying to open the left rear cabin door, which was adjacent to where they had both been sitting. They turned the door handle one way, and tried the other way, but could not open the door.

When the pilot did not see any of the passengers on the water surface, they returned to the aircraft to help them. They swam down and attempted to open the rear left door. Despite considerable effort, with their feet positioned on the airframe either side of the door, the door would not open, so they swam over to the right rear cabin door. The right door was able to be opened, again with a degree of force required, and the pilot pulled the nearest person out and took them to the surface. After taking a breath, the pilot returned and retrieved a second person, before assisting the remaining passengers.

One of the passengers, when they realised they could not open the left rear door, and with the cabin now almost completely filled with water, swam to the right side of the aircraft. They saw their partner was still in their seatbelt, so released it and continued to search for the door handle. They then felt their partner being pulled from them and out of the aircraft. They do not recall how they exited the aircraft but found themselves on the surface. The other passenger who was initially attempting to open the left rear door reported observing their partner, but it was very difficult to see. They then recalled being pulled from the aircraft, however, their partner could not remember how they exited the aircraft.

A nearby vessel rendered assistance to the pilot and passengers and transported them to Hamilton Island for medical attention. Once aboard the vessel, the pilot looked at the aircraft and observed the right main gear wheels had not retracted into the float (Figure 2).

Figure 2: VH-OHU underside of floats, showing right main wheels not retracted

Source: Used with permission, annotated by the ATSB

The pilot and passengers sustained minor injuries, and the aircraft was substantially damaged. It was reported that the aircraft sustained further damage during the retrieval from the water, before being transported to Mackay Airport, for storage.

Context

Pilot information

The pilot held a Commercial Pilot Licence (Aeroplane), with single and multi-engine class ratings and design feature endorsements including retractable undercarriage and floatplane. The pilot also held a current class 1 medical certificate with nil restrictions.

Prior to commencement with Whitsunday Air Services (trading as Hamilton Island Air), the pilot had accrued 563 hours total aeronautical experience, with 696 water landings, in a Cessna 182 aircraft on fixed floats. On 3 September 2024, the pilot underwent a familiarisation/transition flight in a fixed float DHC‑2 aircraft with an approved flight training organisation. The pilot was then employed with Hamilton Island Air. On 10 September 2024, the pilot commenced line training through the operator’s in‑command-under-supervision (ICUS) program, operating the DHC‑2 and the GippsAero GA8 Airvan^[2] aircraft under the supervision of the operator’s ‘fixed wing specialist’ training pilot (see Operational information).

The pilot completed ICUS training with a line check on 8 October 2024. The training pilot set a 20 kt wind limitation for operations at Whitehaven for the next 25 flight hours, for the pilot to fine‑tune their skills ‘in the air and on the water’. The aircraft daily flight records indicated the pilot conducted solo flights on 15 and 25 October, consisting of circuit training at Hamilton Island. In addition, on 18 October they conducted a flight to Whitehaven, with 5 Hamilton Island Air staff as passengers, similar to the tour that was the accident flight. The accident flight was the pilot’s first flight with fare-paying passengers. 

As of the morning of 26 October, the pilot had accrued 28 hours and 84 water landings in VH‑OHU. While the pilot had accrued 84 water landings in an amphibian aircraft, typically, the landing gear was not required to be extended and then retracted during training that consisted of multiple water landings in one session. As such, their gear actuation cycle experience was likely lower.

Helicopter underwater escape training (see Helicopter underwater escape training) was a Hamilton Island Air requirement, for all its helicopter and fixed-wing flight crew, to be completed during their induction and followed by recurrent training every 2–3 years. The pilot completed their initial underwater escape training on 24 September 2024.

The pilot self-reported to being well rested and feeling ‘fully alert’ on the morning of 26 October 2024. In addition, they advised they ‘felt comfortable with the aircraft’ and they had no distractions during the preparations for landing at Whitehaven.

Aircraft information

General

VH‑OHU was an amphibian De Havilland of Canada DHC‑2 Beaver, serial number 826, a predominantly all metal high-wing aircraft manufactured in 1956 and first registered in Australia in 2015.

The DHC‑2 was originally designed and manufactured by De Havilland Aircraft of Canada, Limited. Viking Air Limited was the type certificate holder from 2006 until 2024. In August 2024, Viking Air Limited amalgamated with De Havilland Aircraft of Canada Limited, and De Havilland Aircraft of Canada Limited became the type certificate holder.

The aircraft was powered by a Pratt & Whitney ‘Wasp Junior’ R-985 9-cylinder, single row, air‑cooled radial engine, which drove a Hartzell HC B3R30-4B 3‑blade propeller. The aircraft was fitted with Wipline 6100 series amphibious floats, manufactured by Wipaire.

Cockpit and cabin configuration

There were 2 forward cockpit doors and 2 rear cabin doors. The cabin door handle was located along the aft edge of the door and required the row 1 passenger to reach behind the seat to open the door (Figure 3). The front seats were equipped with 3-point lap-sash style restraints and the 3-person cabin bench seats were equipped with 2-point lap-belt restraints.

Figure 3: Seat and door locations

Source: Pilot’s operating handbook, annotated by the ATSB

Maintenance history

The aircraft logbook statement showed the airframe, electrical, engine, instruments and radio were to be maintained in accordance with the Civil Aviation Safety Authority (CASA) Schedule 5.[3] The float system was to be maintained in accordance with Wipaire instructions for continued airworthiness.

On 6 December 2022, VH‑OHU was subject to a forced landing just after take-off from Hamilton Island. The aircraft was subsequently removed from service. The aircraft was partly disassembled and transferred to Mackay in July 2023. Between January and September 2024, the aircraft underwent scheduled maintenance conducted by a CASA‑authorised maintenance organisation. Additional maintenance included treatment of corrosion and replacement of corroded hardware and components. This included inspection of the landing gear carriage assemblies and replacement of both slide tubes and all proximity sensor switches (see Landing gear actuation system). A landing gear system retraction test was also performed at this time.

The current maintenance release was issued on 3 September 2024 and there were no recorded defects at the time of the accident. The aircraft had accrued about 18 hours on the maintenance release, with a total time of 18,342 hours. Landings were recorded on the maintenance release, however, there was no distinction between water or land, nor if the gear had been retracted during water landing training or circuits from Hamilton Island.

Landing gear system

General

The landing gear incorporated within the amphibious floats is a retractable, quadricycle type with 2 free castoring nose (or bow) wheels and 4 (2 sets of dual) main wheels (Figure 4). Steering on the water is accomplished by a water rudder located at the rear of each float, which is cabled into the existing aircraft rudder system. Steering on land is accomplished by differential braking on the main landing gear wheels.

Figure 4: VH-OHU showing the amphibious float components

Source: Maintainer, annotated by the ATSB

Landing gear actuation system

Landing gear operation is initiated by movement of the landing gear handle, with the extension and retraction accomplished by 2 electrically‑driven hydraulic pumps. When the pilot selects the gear handle to UP or DOWN, hydraulic pressure in the system will drop and pressure switches will automatically turn on the hydraulic pump motors to maintain operating pressure in the system. When the gear cycle is completed, pressure in the system will increase to the limit where the pressure switches automatically shut off the pumps. If the pressure in the system drops to a preset value, the pressure switches turn the pump motors back on and build up the pressure to the limit again. Only the main gear system operation will be detailed in this report. 

The main gear is mechanically locked in both up and down positions. When the gear is selected to UP, the main gear down hook unlatches from the rear locking pin. Hydraulic pressure exerted on the actuator piston drives the carriage assembly to move forward along the slide tube, with the wheels moving aft, until the gear up hook latches on the forward locking pin (Figure 5). With no further movement once all 4 gear are retracted into the float, hydraulic pressure will increase until the pumps automatically switch off. 

Figure 5: Main gear assembly diagrams, including VH‑OHU forward locking pin (inset)

Source: Wipaire and the maintainer (inset), annotated by the ATSB

The landing gear indication panel, to the right of the pilot’s seat (at the base of the control column), contained 10 lamps. Four blue to indicate the 2 nose and 2 main gear were up, 2 red to show hydraulic pump operation and 4 amber to indicate the gear was down. In addition to the standard equipment, VH‑OHU was also fitted with a hydraulic pressure gauge for pilot reference (Figure 6). 

Each gear actuation operates independently (no set sequence) and therefore, the main gear UP and DOWN lamps are progressively activated by proximity switches, when the respective latch hook nests over the locking pin. The red hydraulic pump lights should extinguish shortly after all 4 UP or DOWN lamps are illuminated.

The airplane flight manual supplement for the amphibian floats described ‘bulb replacement during flight’. Where a lamp is not illuminated as expected, the pilot can readily remove the lamp and a known functioning lamp can be inserted into that location. This allows the pilot to determine if the non-illumination is a defective bulb, or other system issue. 

Figure 6: Typical landing gear panel

Source: Used with permission, annotated by the ATSB

The airplane flight manual supplement for the amphibian floats included the following:

The supplement further included that, where cycling of the gear does not rectify an asymmetric condition, rather than landing on water, the preferred option is to conduct the landing on a hard surface or grass:

Landings of this sort produce little tendency to nose over when checklist procedures are used, even when conducted on hard surface runways, and will result in little or no damage to the floats.

Mirror

In addition to the landing panel gear position indication, the aircraft was also fitted with an optional mirror, installed on the left wing (Figure 7). Wipaire advised the mirror was not part of its float modification, however, it was aware it was a common addition to float planes. 

This mirror allowed the pilot in the left seat to view the position of all 4 gear. This was particularly effective to confirm if the right main gear was retracted or extended from the underside of the right float, which was not possible without the mirror. The company pilots the ATSB spoke with reported varying opinions on the effectiveness for observing the right main gear via the mirror (see Operational information). However, all reported the mirror on the aircraft was correctly aligned following the recent maintenance and was effective in determining gear position.

Figure 7: Left wing mirror location, with representation of extended gear visible view

Source: Used with permission, annotated by the ATSB

Amphibian gear advisory system

The aircraft was also fitted with a Wipaire-authorised amphibian gear advisory system (AGAS), which provided the pilot with supplementary gear position information. Following departure, once the aircraft increased through a threshold airspeed, the system was armed. Upon slowing down through the threshold airspeed, in preparation for landing, the AGAS ‘Gear Advisory’ amber lamp (Figure 8), positioned on the instrument panel in front of the pilot, would illuminate. In addition, an audio annunciation, heard through the front seat headset/s, would commence. Where all 4 gear were retracted, the annunciation would consist of ‘gear up for water landing’ (female voice). Conversely, where all 4 gear were extended, the annunciation would be ‘gear down for runway landing’ (male voice). The audio annunciation would repeat every few seconds, until silenced by the pilot pressing the gear advisory lamp. The annunciation was a prompt for the pilot to check their gear configuration was correct for the intended landing surface.

Figure 8: Example of location of gear advisory lamp in DHC‑2 instrument panel

Note: the insert is taken from the AGAS airplane flight manual supplement. Source: Used with permission, annotated by the ATSB

The AGAS also had a ‘check gear’ advisory. In this case, when the aircraft slowed through the threshold airspeed, the gear advisory amber lamp would illuminate and the annunciation of ‘check gear’ would be heard in the same female voice and similar tone as that for the ‘gear up for water landing’ advisory. There were no additional tones associated with this alert. Check gear indicated an asymmetric condition in the landing gear, where one or more proximity switches had not closed. This was designed to prompt the pilot to abort the landing and troubleshoot the discrepancy. The airplane flight manual supplement for the AGAS included the warning:

In addition, to ensure the system was functioning prior to flight, the ‘operational checklists’ detailed the ‘before take-off’ checks as:

• annunciator switch – PRESS and HOLD for 2-3 seconds
• test audio – VERIFY message is audible
• annunciator switch – VERIFY annunciator light flashes.

Wipaire advised that the ‘test’ audio check contained the gear up and gear down messages only. That is, the check gear annunciation was not included in the system test audio.

Wipaire maintenance documentation

The Wipaire instructions for continued airworthiness (ICA) described the general servicing of the floats and landing gear. The manual also included the following warnings to ensure corrosion from saltwater operations was kept to a minimum:

…

The ICA 25-hour maintenance requirements for the landing gear included washing the aircraft and floats with fresh water and inspecting surfaces and hardware for signs of corrosion, especially with saltwater use. In addition to specific nose gear maintenance actions, the main wheel bearings and main gear carriages were to be greased. This maintenance on VH‑OHU was typically conducted by the maintainer. The maintenance documentation recorded that a 25-hour float inspection was conducted by the maintainer on 5 October 2024, about 15 hours since the issue of the maintenance release.

The ICA inspection time limits and checklist section did not include a specific check for corrosion on the slide tube. Wipaire advised it was covered in the servicing section for ‘movable parts’, which detailed the inspection:

For lubrication, servicing, security of attachment, binding, excessive wear, safe-tying, proper operation, proper adjustment, correct travel, cracked fittings, security of hinges, defective bearings, cleanliness, corrosion, deformation, sealing and tension.

The 25-hour inspection was conducted with the aircraft on extended landing gear. In this configuration, the forward end of the slide tube could be inspected. However, the carriage assembly was positioned at the aft end of the slide tube, preventing inspection at this location. A gear retraction test, to check for correct operation of the gear up and down lock hooks, was to be conducted at 200-hour intervals. With the gear retracted, this then provided the opportunity to inspect the aft end of the slide tube.

Wipaire published service letter #80 AT-802 Fire Boss Slide Tube Corrosion in 2006. It described reports from operators of ‘sticking main gear actuators due to corrosion on the slide tube’. It noted that the corrosion was partially caused by gravel or debris from the main landing gear tyres eroding through the hard anodised surface of the slide tube, exposing the underlying aluminium, which was more susceptible to corrosion. Part of compliance included inspecting the slide tube for erosion and/or nicks and wiping the slide tube down with a clean rag soaked in lubricant. Wipaire advised there was no specific service letter to address corrosion for the 6000/6100 series floats.

Pilot maintenance

Due to the salt laden environment and exposure to seawater, the operator reported washing the aircraft with fresh water at the end of each operating day. In addition, greasing of the nose and main gear components, and other aircraft care activities, were periodically carried out. These additional tasks were to be carried out by an appropriately trained pilot, however, it was not recorded on the maintenance release or other formal record. It was also noted that there was no practice of washing the aircraft if it had not been operated for several days. 

The maintainer conducted the pilot maintenance training, demonstrating the additional maintenance tasks. The pilot of VH‑OHU had not yet received the formal training prior to the accident but advised that they had been shown these tasks by their training pilots.

Meteorological information

The meteorological conditions reported by the pilot at the time of accident were consistent with the Bureau of Meteorology forecast, with east-south-east winds of about 7–8 kt and good visibility. In addition, the pilot’s report and passenger footage showed the water conditions were ideal for float plane operations and sun glare was not angled into the cockpit and across the instrument panel.

Wreckage information and component examination

The ATSB did not attend the accident site or wreckage examination in Mackay, instead the ATSB liaised with the maintainer and the maintenance organisation that conducted the post-accident examination of the landing gear. The ATSB also reviewed images and video footage taken during these examinations.

Initial examination

The maintainer examined the aircraft, in the presence of the insurance representative, after it was retrieved from the ocean and provided the following observations regarding the landing gear system:

• the aircraft was significantly disrupted during the retrieval from the water, including damage to the landing gear panel, which prevented the landing gear selector position to be definitively established
• the landing gear appeared undamaged
• hydraulic fluid was drained and appeared to be of expected quantity, with no water contamination
• the 4 blue lamps were removed for testing, however, their location prior to removal was not recorded
• one of the blue lamps failed testing, however, it could not be determined if this was from seawater immersion or a pre-existing fault.

The wreckage was then transferred to Mackay for storage and further examination.

About 2 weeks after the accident, the landing gear was examined by the maintainer and an engineer from another CASA-authorised maintenance facility. They provided a report to the ATSB, with following general observations:

• hydraulic pump 1 and 2, AGAS and gear lamps circuit breakers were engaged, indicating the system was operating as expected
• it was not possible to carry out a continuity and functional check of the gear panel indication system due to corrosion and moisture from saltwater ingress
• fuses for pumps 1 and 2 ‘ON’ lamps tested serviceable
• both nose gear assemblies and the left main gear were observed to be up and locked, indicating a complete retraction
• the right main gear was extended
• some corrosion was noted on the forward face of both the left and right carriage assembly to slide tube interface.

The maintainer advised the ATSB that, when they tried to move the left main gear carriage, it initially did not move. However, ‘a small knock with a hammer freed the carriage’, which then moved freely. The carriage was likely held up by the observed minor corrosion at the slide tube interface. Further, there was ‘little to no damage’ on the slide tube, compared to the same location on the right slide tube.

Right main gear examination

Detailed examination and testing of the right main gear assembly was then conducted. The report included the following observations: 

• the down hook was found to be free of the locking pin (unlocked)
• the right main gear was approximately 1.5–2 mm from fully down
• gear position light proximity switches tested for resistance to ground with no issues
• continuity testing of the proximity sensor switches showed UP and DOWN ‘open’, which was correct for the current configuration (gear mid travel).

Hydraulic pressure was then applied to the right main gear using a hand pump and calibrated pressure gauge. With 870 psi applied in the retraction direction, the carriage did not move along the slide tube. This was despite progressively adding oil to the slide tube/carriage interface, supplying grease to the carriage, disconnecting the shock strut and applying mechanical assistance via a pry bar.

The hydraulic pressure supply was then transferred to the extend direction. The carriage and slide tube moved together and closed the 1.5–2 mm gap. With this actuation, the actuator piston moved relative to the carriage assembly and the DOWN lock engaged as per design specifications. Testing of the proximity switch showed it to be closed, correct for the configuration. The direction of hydraulic pressure was reversed to retract and the DOWN lock was observed to disengage freely, with the proximity switch again testing correctly.

The report noted that at no time did the carriage move relative to the slide tube during the testing, establishing that the carriage assembly was seized on the slide tube. When the slide tube was removed from the float, a slide hammer and block of wood was successful in separating the carriage assembly from the slide tube. A significant amount of corrosion was then noted on the slide tube.

The ATSB then requested the left and right slide tubes and carriage assemblies be provided for further examination.

Component examination

The ATSB and Wipaire conducted testing and analysis to try to determine the circumstances that allowed the corrosion to develop. Examination of the left and right slide tubes and carriage assemblies was conducted at the ATSB’s technical facilities in Canberra, Australian Capital Territory.

The right slide tube had 2 bands of corrosion that corresponded with the bushing locations in the carriage, at about the fully extended location (Figure 9). The left slide tube showed no similar damage. Both carriage assemblies exhibited grease around the UP and DOWN hooks and internally. The components were not serialised, so the history of the carriages prior to the aircraft entering Australia could not be determined.[4] 

Figure 9: Comparison of slide tubes, showing corrosion bands on the right slide tube (on the right) and location of bushings examined by the ATSB

Source: ATSB and used with permission, annotated by the ATSB

Detailed examination of the components was then conducted, with reference to the Wipaire-supplied specifications.

The slide tubes were manufactured from aluminium with an anodised coating. The slide tube dimensions were measured to be within specifications and the anodised layer was the correct thickness. The slide tube surface was non-conductive, as expected for an anodised layer.

The bushings were a tri-layer construction, with a base layer of steel, with sintered (porous) bronze and then coated in a PTFE[5] ‘sliding layer’. The bushing could be replaced and therefore, the carriage time in service did not necessarily correspond to the bushing time in service. The bushings of both carriages were examined, with observations including the internal diameters of all bushings were within drawing tolerances and the right bushings were more worn than the left (Figure 10).

Figure 10: Difference in bushing wear with the left (left) showing largely intact PTFE layer (grey) and right (right) showing significant exposure of the sintered bronze layer

Source: ATSB

The right carriage bushing located near the grease nipple was sectioned. Examination identified areas where the PTFE layer was not present, exposing the bronze layer and showing some evidence of scoring (Figure 11). The PTFE layer was non-conductive in contrast to the bronze.

Figure 11: Right carriage bushing surface showing Teflon/lead layer (grey), exposed bronze layer (copper) and some evidence of scoring (bright lines)

Source: ATSB

The slide tube corrosion patterns were consistent with galvanic corrosion between the exposed bushing bronze layer and the aluminium slide tube base metal, in the presence of salt from coastal operations. The difference in wear between the left and right carriage bushings likely influenced the degree of corrosion on the respective slide tubes. The bushings with a higher amount of retained, non-conductive PTFE layer showed significantly less corrosion on the corresponding slide tube.

The ATSB determined that there were no material or manufacturing issues identified with the slide tubes, and therefore the thin, hard anodised coating was likely damaged or worn through in this area, to allow for the dissimilar metal contact. This type of damage was also observed in discrete locations in deeper score marks on the slide tube, away from the main areas of corrosion. 

Damage to the anodise was unlikely to have been directly from the worn bushings, since the bronze is softer than the hard anodise layer, but it was possible for dirt, sand or other abrasive debris to have become entrapped between the bushings and slide tube. While there was no significant entrapped material identified during the ATSB examination, the mechanism was shown to exist, as described in Wipaire service letter #80. 

Operational information

Operator overview

Whitsunday Air Services, trading as Hamilton Island Air, conducted tourist charter flights to various locations in the Whitsundays, Great Barrier Reef and Hamilton Island areas, using a variety of fixed-wing and helicopter types. At the time of the accident, it operated a fleet of 17 helicopters and 3 fixed-wing aircraft: VH‑OHU, a GA8 Airvan and a Cessna 208.

Training pilot observations

The operator had an appointed fixed-wing specialist, who oversighted the fixed-wing operations and pilot training. The fixed-wing specialist (training pilot 1 – TP1) had advised the operator their intention to depart the organisation in September 2024. In August, they commenced correspondence with the accident pilot, in preparation for their employment and training. 

TP1 collected VH‑OHU from the maintenance organisation in Mackay. Due to the aircraft coming out of extended maintenance, and TP1 having not operated it for a period of time, TP1 reported conducting a series of test flights, including water landings near Mackay and then en route to Hamilton Island. TP1 reported that the landing gear and AGAS were operating as expected. In addition, TP1 advised the mirror was correctly oriented to view all 4 gear. TP1 then commenced training the accident pilot on VH‑OHU, between 10 and 20 September 2024, before leaving the organisation. 

Training was then conducted by the current fixed-wing specialist (training pilot 2 – TP2), from 5 October 2024. The training again included land and water landings, with TP2 advising the landing gear and AGAS systems were functioning correctly. TP2 advised the left mirror was correctly oriented, however, the right main gear could sometimes be difficult to distinguish from the background contrast (such as terrain, sky, water). TP2 reported their preference for having an additional right-side mirror, and they were in the process of procuring a second mirror at the time of the accident.

Pilot recollections

Accident day

With regard to the day of the accident, the pilot reported:

• they did not feel any operational or time pressure
• they were comfortable with operating the aircraft solo, and with passengers
• the landing area only contained a few vessels, therefore, workload was not increased
• there were no distractions from the passengers during the approach to land and landing
• while there was a checklist available, the pre-landing checks were completed from memory, which was permitted by the operator’s procedures
• they observed 4 blue lights indicating the gear was up for a water landing
• they checked the mirror
• they did not recall hearing the AGAS annunciator just prior to landing
• during the accident sequence the aircraft flipped ‘within a second and I was underwater, upside down, almost instantly submerged, no air at all’.

Following the aircraft becoming submerged inverted, the pilot advised that, due to their recent helicopter underwater escape training, they ‘came right into action’ and ‘wasted no time’. The pilot advised that they would recommend the training to pilots operating sea planes or ‘any planes over water’.

Further, the pilot reported that, had they observed the extended right wheel, they would not have conducted the water landing, and would have returned the aircraft to Hamilton Island for a runway landing.

Training and aircraft systems

The pilot reported that they were happy with their training from both training pilots. In addition, they did not perceive any difficulties with training on the DHC‑2 and GA8 Airvan concurrently. 

When discussing the mirror, the pilot described its importance in determining gear position. However, they also reported that there might be a blind spot that means the right main gear may be difficult to see.

When asked by the ATSB if the AGAS self-test was successful prior to the accident flight, the pilot reported to not being aware of this procedure. The pilot also reported to not have heard the AGAS ‘check gear’ annunciation during their training.

Seaplane operations guidance

The Seaplane Pilots Association published guidance on amphibious gear management best practices, to ‘enhance safe operations within the seaplane community’.[6] The guidance advocated the use of checklists and described triggers or cues, with each phase of flight, ‘to deter landing with the gear in the wrong position’. The ‘on water-based landing’ section included, in part:

• several gear-position validation checks, during initial flyover, pre-landing operations (1st power reduction, setting flaps et cetera) and establishing on final approach to land
• verbalise each gear position validation while visually confirming
• pay attention to the gear advisory system, if installed.

In addition, the guidance stated, ‘it is very important to crosscheck the surface intended for landing with the gear position selected and where the gear actually is positioned’ and included:

As general guidance, an amphibious aircraft should be considered more vulnerable to a catastrophic accident, which may include serious injury and death, with the gear down. While all efforts should be taken to avoid landing on either a runway or a waterway with the gear in the wrong position, landing on a runway with the gear up tends to be much more benign, with minimal damage and injuries, compared with landing on water with the gear down. Avoiding either scenario is best done by being attentive and not complacent.

Survival aspects

Helicopter underwater escape training (HUET)

HUET has been in use around the world since the 1940s and is considered best practice in the overwater helicopter operating industry. HUET is designed to improve survivability after a helicopter ditches or impacts into water. Fear, anxiety, panic and inaction are the common behavioural responses experienced by occupants during a helicopter accident. In addition to the initial impact, in-rushing water, disorientation, entanglement with debris, unfamiliarity with seatbelt release mechanisms and an inability to reach or open exits have all been cited as problems experienced when attempting to escape from a helicopter following an in-water accident (Rice and Greear, 1973).

The training involves a module (replicate of a helicopter cabin and fuselage) being lowered into a swimming pool to simulate the sinking of a helicopter. The module can rotate upside down and focuses students on bracing for impact, identifying primary and secondary exit points, egressing the wreckage and surfacing.

The ATSB has previously emphasised the importance of HUET for all over-water helicopter operators in other investigations including AO-2018-022, AO-2019-008, AO‑2020-003 and AO-2023-044. Further, HUET is included in the ATSB’s Safety Watch Reducing the severity of injuries in accidents involving small aircraft.

Safety briefing 

The ATSB viewed the safety briefing video and noted it described the operation of door handles from across the operator’s fleet, although the aircraft associated with each handle was not explicitly stated. When the ATSB discussed the briefing process with the passengers, they recalled that the video had a lot of different door handles. One passenger also noted the video seemed to be focused more on helicopters, rather than the floatplane. However, the passengers recalled the pilot briefing them at the aircraft and showing them how the door handles worked on VH‑OHU.

Emergency egress

In this accident, the passengers required assistance from the pilot to egress from the submerged aircraft. Had the pilot been unable to assist, the outcome may have been more severe.

This possibility was reported by the Transportation Safety Board of Canada (TSB) in investigation A09P0397 Loss of control and collision with water involving a DHC‑2 on 29 November 2009. Following the collision with water, the pilot and one passenger survived, however, the other 6 passengers succumbed to injuries from immersion. The report included the following safety issue:

Over the last 20 years, some 70% of fatalities in aircraft that crashed and sank in water were from drowning. Many TSB investigations found that the occupants were conscious and able to move around the cabin before they drowned. In fact, 50% of people who survive a crash cannot exit the aircraft and drown.

The TSB recommended ‘the Department of Transport require that all new and existing commercial seaplanes be fitted with regular and emergency exits that allow rapid egress following a survivable collision with water’ (A11-05).

TSB report A18A0053 Loss of control and collision with water, involving a DHC‑2 on 11 July 2018 noted the aircraft became inverted during the accident sequence. One pilot escaped through the broken front windscreen. The other pilot was unable to open their forward right door nor the cabin door, however, the first pilot was able to open the cabin door from the outside. Neither pilot had undergone emergency egress training, nor was it required. Further, the report included:

Emergency door release mechanisms, better door handles, and push-out windows have been developed for certain types of floatplanes. Some floatplane operators have installed these modifications, but many have not. 

Regulatory requirements for mandatory egress training for commercial floatplane pilots may result in some improvement in emergency egress from commercial seaplanes. However, if the regulator does not mandate or promote voluntary modifications to normal exits, seaplanes will continue to operate with exits that could become unusable following an impact, diminishing the chance occupants have to exit the aircraft following a survivable accident.

Push-out windows

Viking Air Limited (the type certificate holder at that time, now held by De Havilland Aircraft of Canada, see Aircraft information) developed ‘push-out windows’ (Figure 12) and published service bulletin V2/0003 New cabin door windows that incorporate a ‘push-out’ feature in July 2010. The service bulletin noted:

- A series of incidents involving float equipped aircraft has highlighted the need to improve emergency egress from the cabin.

- The Cabin Door Push-Out Window Kits contain a rubber-mounted right-hand and/or left‑hand passenger window which affords additional egress opportunities from the aircraft.

- Viking has designed new windows for the passenger doors that incorporate the same ‘push-out’ feature used for many years on helicopters operating overwater.

- Viking Air Limited strongly recommends that this safety improvement be incorporated on aircraft operating on floats and any wheeled aircraft operating over water, or as directed by the operator’s Regulatory Authority.

Figure 12: Example of main cabin door push-out window

Source: De Havilland Aircraft of Canada and Naomi Lacey (inset), annotated by the ATSB

De Havilland Aircraft of Canada advised it has supplied about 130 kits worldwide, with one kit to Australia. VH‑OHU was not fitted with the push-out windows, nor was it required by regulations.

Revised door latches

Viking Air Limited published service bulletin V2/0004 Installation of an automotive style cabin door latch system in November 2010. The service bulletin cited the reason as ‘the dual automotive (pull) style cabin door latch system provides better egress from the cabin in the event of an emergency’ (Figure 13). The service bulletin also noted:

- Viking Air Limited (Viking) has designed a dual automotive (pull) style cabin door latch system that is more familiar and intuitive to passengers. The existing single latch handle (rotating style) at the rear of the door has been replaced by one pull style latch handle at the same location and a second pull style latch handle in the forward portion of the door. This allows passengers in the forward and rear cabin seats to open the cabin doors in an emergency situation.

- Viking strongly recommends that this safety improvement be incorporated on all DHC‑2 aircraft or as directed by the operator’s Regulatory Authority.

De Havilland Aircraft of Canada advised it had supplied 70 door latch kits to date. VH‑OHU was not fitted with the modified door latch system, nor was it required by regulations.

Figure 13: Representation of revised door latches, with VH‑OHU door in inset

Note: the rotational-style door latch, as was in VH‑OHU, operates in one direction only. Source: De Havilland Aircraft of Canada and the operator, annotated by the ATSB

Similar occurrences

There have been a number of occurrences involving DHC‑2 where one or more wheels were extended during a water landing resulting in the aircraft nosing over and becoming inverted. This has been evidenced in several United States National Transportation Safety Board (NTSB) accident reports as summarised below.

N218RD at Oak Island, Minnesota, on 22 May 2021 (CEN21LA244)

The aircraft departed with a known hydraulic leak in the landing gear system. During the flight, the degraded hydraulic system resulted in the inadvertent extension of the left main gear. This was not identified by the pilot and the aircraft nosed over upon landing on the water and became inverted. The pilot and one passenger were not injured, and one passenger sustained serious injuries.

N9558Q at Stehekin, Washington, on 17 May 2008 (LAX08FA144)

The pilot did not raise the landing gear after take-off. The pilot also reported the flight was turbulent and bumpy, with slow airspeed due to the heavy load. This resulted in numerous AGAS annunciations, until the pilot pulled the circuit breaker to disable the ‘nuisance’ alerts. The pilot intended to reset the AGAS prior to landing but did not do so. When the aircraft landed on the water with the wheels extended, it abruptly nosed over and became inverted. The pilot and 2 passengers survived, and 2 passengers were unable to exit the aircraft and succumbed to immersion. 

N60TF at Sitka, Alaska, on 30 May 2003 (ANC03LA054)

The pilot advised they forgot to raise the landing gear following departure from land. During the water landing, with the wheels extended from the floats, the aircraft nosed down in the water. The pilot was uninjured.

N4478 at Aleknagik, Alaska, on 28 August 2002 (ANC02FA106)

The NTSB found the pilot did not raise the landing gear following departure from land. During the water landing, with the wheels extended from the floats, the aircraft nosed over and became inverted. The 2 passengers escaped with minor injuries and the pilot sustained fatal injuries attributed to immersion.

Safety analysis

Introduction

On the morning of 26 October 2024, the pilot of a De Havilland Aircraft of Canada DHC‑2, registered VH‑OHU, departed Hamilton Island aerodrome, Queensland, with 4 passengers on board for a short scenic flight to Whitehaven Beach, Whitsunday Island. Upon touching down on the water, the aircraft yawed to the right, nosed over and became submerged inverted. The pilot and 4 passengers sustained minor injuries and the aircraft was substantially damaged.

This analysis will discuss the right main gear failing to retract, the unsafe configuration not being identified by the pilot and delayed egress of the passengers. In addition, the analysis will consider why the pilot did not hear the gear annunciation. Further, the pilot’s recent underwater escape training and availability of enhanced egress aircraft modifications will also be discussed.

Right main landing gear failed to retract

Immediately following the accident, the right main gear could be seen extended from the float. Examination of the aircraft found no evidence of leakage, loss or contamination of the hydraulic fluid, and all landing gear circuit breakers were engaged. Further, the nose and left main gear had successfully retracted, indicating the anomaly was likely isolated to the right main gear.

During retraction, the main gear travels aft as it swings up into the float. Had the gear been mid-travel, such as still cycling, the impact with the water would have forced the gear to retract up into the float. Therefore, it was unlikely the right main gear moved during the impact sequence. This was consistent with the post-accident examination, which identified that the right carriage assembly had seized on the slide tube at the almost fully extended position. 

Once removed from the aircraft, forceful removal of the carriage resulted in the identification of advanced corrosion on the right slide tube. The 2 bands of corrosion were coincident with the location of the carriage bushings, near the full gear extension position. This would be expected as the aircraft was predominantly parked on land, with the gear extended.

The investigation considered scenarios conducive to the formation of this corrosion. The maintenance records prior to the aircraft entering Australia in 2015 were not available, as such, the service history of the main gear carriage assemblies, including the bushings, was unknown. While there was a significant difference in the condition of the left and right slide tubes, both tubes were installed at the same time and therefore subject to the same operational and environmental conditions.

The operator advised the aircraft was rinsed with fresh water at the end of the operating day, however, this was not formally recorded and there was no practice for rinsing when the aircraft was not operated for several days. The aircraft records showed the maintainer conducted a 25-hour float inspection on 5 October 2024 and grease was observed on the assemblies during post‑accident examination. However, as there was no requirement to retract the gear for this inspection, the position of the carriage assembly precluded visual examination of the slide tube at the location where the corrosion had developed.

Examination of the carriage bushings identified that the right bushings exhibited more wear and loss of the PTFE ‘sliding layer’, which runs along the slide tube. This had the potential for galvanic corrosion to form, however, required the degradation of the anodised layer on the slide tube to also be present. Insufficient cleaning, inadequate application of grease and/or accumulation of dust or dirt on the slide tube are known contributors to degradation of protective layers. While the extent to which they were contributory in this case was not able to be determined, it was likely that the identified corrosion resulted in the right main gear seizing.

Pilot did not identify extended right main gear

The pilot reported observing 4 blue ‘gear up’ lamps illuminated, at about Tongue Point, and during their pre-landing checks. The passenger footage showed sun glare was not angled in the direction of the landing gear panel and the pilot advised they were able to clearly identify what lamps were illuminated. However, when tested post‑accident, one blue lamp did not illuminate, although it could not be determined if this failure was due to seawater immersion or pre-existing. Further, the location of the failed lamp could not be determined as the lamps were not identified on removal from the landing gear panel. Despite this, failure of any lamp to illuminate requires troubleshooting by the pilot prior to landing. The pilot can readily determine if the lack of illumination of a lamp is due to a failed bulb or other system issue. 

The main right gear UP and DOWN proximity switches tested serviceable during the post-accident examination. The examination also noted the right main gear had unlatched from the DOWN location and moved about 1.5–2 mm in the retract direction before becoming seized. During the landing gear retraction sequence, pressure in the hydraulic system would increase until the pumps automatically switched off and the red ‘in-transit’ lamps would extinguish. In this configuration, with nil movement in the right main gear due to the seizure, it was expected that only 3 blue lamps would have been illuminated. Therefore, the investigation could not reconcile the pilot’s recollection of there being 4 blue lamps illuminated.

The mirror provided an additional method to identify the landing gear configuration. Training pilot 1 advised they could observe all wheels in the mirror following the aircraft repairs. Training pilot 2 reported sometimes experiencing difficulty in observing the right main wheels from the mirror. The accident pilot reported a blind spot, which hindered their ability to see the right main gear in the mirror. However, during the pre‑landing checks, the accident pilot reported they checked the mirror and did not observe any wheels protruding from the floats and continued with the water landing.

Another method to identify the gear position was via the amphibian gear advisory system (AGAS), which provided a visual and audio annunciation as the aircraft slowed for landing. The pilot had been communicating via the radio with the helicopter pilot, thereby showing the audio system in VH‑OHU was operational and that the AGAS annunciation was able to be heard through the headset. However, the pilot reported they could not recall hearing any annunciation prior to landing on the water. Due to disruption of the floats during the accident, the system could not be functionally tested. The pilot advised they were not aware of the pre-flight self-test of the AGAS and therefore this was not conducted prior to the accident flight. While it remained a possibility that the AGAS did not alert the pilot to an asymmetric condition prior to the landing, all 3 pilots reported the AGAS had been functioning correctly in the preceding weeks. Therefore, while it could not be conclusively determined, it was more likely the system was operational.  

The pilot’s 84 water landings in VH‑OHU did not necessarily represent the number of times they had actuated the landing gear, however, they did select the gear to retract after departing Hamilton Island. In addition, the pre-landing checks required the pilot to utilise the aircraft systems to ascertain gear position prior to each landing, regardless if the gear was cycled. Further, the pilot also reported no issues with distractions, workload or experiencing time pressures. 

Therefore, while the aircraft was fitted with multiple systems to confirm the status of the landing gear, for undetermined reasons the pilot did not identify that the configuration was unsuitable for a water landing. This resulted in the aircraft yawing to the right, nosing over and becoming submerged and inverted, a known consequence of water landings with one or more gear extended.

Landing gear annunciator 

The pilot advised the ATSB that they did not recall hearing the AGAS annunciation just prior to the landing. The ATSB’s analysis concluded the AGAS was more likely than not operational at the time of the accident. The investigation therefore considered potential reasons for the audio alert not being heard or being dismissed.

The ‘gear up for water landing’ and ‘gear down for runway landing’ are advisory only and an opportunity for the pilot to check the gear selection matches their intended landing surface. In contrast, the ‘check gear’ annunciation was alerting the pilot that the 4 gear were not all fully up or down and in an unsafe configuration for landing. However, the ‘gear up’ and ‘check gear’ both used a similar female voice and there were no additional tones to indicate the heightened importance of the ‘check gear’ alert. Further, when below the threshold airspeed, the amber ‘gear advisory’ lamp would illuminate, irrespective of the gear configuration. 

The purpose of auditory warnings is to attract attention to a problem (Salvendy & Karwowski, 2021). Ideally, advisory annunciations would sound distinctly different to other alerts to assist pilots to recognise there is problem requiring their action. Making alerts distinctive from other sounds can also inform the pilot of the priority or urgency of the problem (Yeh et al. 2016, FAA, 2016). During approach to land, with the gear in an asymmetric configuration, the AGAS would have enunciated ‘check gear’, indicating an unsafe condition. 

As the pilot would have expected to hear an annunciation with a female voice during landing, there was little to distinguish it from an alert that required action. In addition, the pilot reported they had not heard the ‘check gear’ alert during the training, reinforcing the female annunciation was to be expected and normal. This increased the risk that a pilot would not recognise that the landing gear was in an unsafe condition and removed an opportunity to consider a runway landing, the preferred option in this scenario. However, as the pilot reported not hearing any annunciation prior to landing, there was insufficient evidence to determine if the lack of distinction between the ‘gear up’ and ‘check gear’ annunciations contributed to the accident.

Passengers’ delayed egress

During the accident sequence, the aircraft rapidly filled with water, giving all on board little time to react. Despite being temporarily tangled in their seatbelt, the pilot readily exited the aircraft and swam to the surface. When no passengers appeared, the pilot swam back to the aircraft.

The 2 passengers seated next to the left rear cabin door reported they quickly released their seatbelts, and both attempted to open the door. The pilot was trying to open this door at the same time, without success. The 2 passengers recalled they attempted to locate the right rear cabin door, which was about coincident with the pilot’s decision to also try this door. The pilot managed to open the right rear door and assisted the passengers to the surface. 

The ATSB considered the circumstances that prevented the left rear door from being easily opened following the accident. It was possible that water pressure from the outside was greater than inside the cabin, until equalising as the cabin filled with water. Alternatively, distortion to the airframe during the impact sequence could have prevented door operation. While the reason could not be determined, this contributed to the delayed evacuation from the submerged aircraft.

Underwater escape training

The pilot had completed operator-required helicopter underwater escape training about one month prior to the accident. They attributed this training to their prompt escape from the inverted and submerged aircraft, and subsequent assistance to the passengers. As evidenced in previous ATSB investigations, this training has been shown to significantly increase the chances of survival in the event of a collision with water.

Enhanced egress aircraft modifications

Following multiple similar accidents where occupants initially survived but were subsequently fatally injured from immersion, the Transportation Safety Board of Canada recommended the fitment of regular and emergency exits that allowed rapid egress in the event of a collision with water. Consequently, Viking Air Limited developed push-out windows and more intuitive automotive-style door latches for the main cabin door. These modifications were not fitted to VH‑OHU nor were they required by regulations. 

In this accident, 2 of the passengers were actively searching for a means of escape, but ultimately required the pilot to open the door. However, if the pilot had been unable to assist, the accident could have resulted in dire consequences. Acknowledging that people behave differently in emergency situations, providing an alternative means of escape where one or more doors cannot be opened, increases the chance of survival. This is most relevant with submerged aircraft, yet can also expediate egress for land‑based accidents, particularly those involving a post-accident fire. 

Findings

ATSB investigation report findings focus on safety factors (that is, events and conditions that increase risk). Safety factors include ‘contributing factors’ and ‘other factors that increased risk’ (that is, factors that did not meet the definition of a contributing factor for this occurrence but were still considered important to include in the report for the purpose of increasing awareness and enhancing safety). In addition ‘other findings’ may be included to provide important information about topics other than safety factors.  These findings should not be read as apportioning blame or liability to any particular organisation or individual.

From the evidence available, the following findings are made with respect to the landing gear malfunction and collision with water involving De Havilland Aircraft of Canada DHC‑2 Beaver, VH‑OHU, near Whitehaven Beach, Whitsunday Island, Queensland, on 26 October 2024. 

Contributing factors

• Likely due to corrosion, the right main landing gear assembly seized near the fully extended position, which prevented retraction after take-off from Hamilton Island.
• During preparations for a water landing, for undetermined reasons, the pilot did not identify the landing gear was in an unsafe condition. As a result, the aircraft landed with the right main wheels extended and then yawed to the right, nosed over and became submerged inverted.

Other factors that increased risk

• The cautionary 'check gear' annunciation was very similar to the advisory annunciation for a normal water landing, increasing the risk that a pilot would not recognise that the landing gear was in an unsafe condition.
• Following the impact, and with the aircraft submerged, the rear left door was unable to be opened by either the pilot or the passengers. As a result, the evacuation of the passengers was delayed.

Other findings

• As required by the operator, the pilot had recently completed helicopter underwater escape training, which aided with their prompt underwater egress and subsequent rescue of the passengers from the inverted and submerged aircraft.
• Push-out windows and door handles designed to expedite egress in an evacuation were available for retrofit on the DHC‑2 Beaver aircraft. VH‑OHU did not have either fitted and nor were they required to by regulation. 

Safety actions

Whether or not the ATSB identifies safety issues in the course of an investigation, relevant organisations may proactively initiate safety action in order to reduce their safety risk. The ATSB has been advised of the following proactive safety action in response to this occurrence.

Safety action by Hamilton Island Air

Hamilton Island Air advised the following safety action was undertaken:

• installation of a second mirror on the right wing of its current DHC‑2 aircraft
• formal initial and refresher training on the pilot maintenance tasks
• implementation of a daily washdown and preventative maintenance procedure checklist, which included a sign-off section to formally record when the activities were completed and by whom
• implementation of a minimum weekly systems check flight, including landing gear cycle, where the aircraft had not been recently operated
• implemented initial and annual theory ground school training, flight characteristics training and 180-day proficiency flight checks for all floatplane pilots, conducted by authorised flight training organisations.

Safety action by the Civil Aviation Safety Authority

Following review of the draft investigation report, the Civil Aviation Safety Authority advised it was intending to release airworthiness bulletin AWB 32-029 Issue 1 Supplementary Type Certificated Amphibian Float Main Gear Slide Wear in Marine Environments. Reflecting the information contained in the ATSB’s investigation report, the bulletin contains advice to operators and maintainers highlighting the importance of inspection and preventative maintenance aspects for retractable landing gear carriages fitted to amphibious aircraft when operated in a marine environment. The bulletin recommended that:

• during scheduled maintenance of the landing gear, particular attention should be applied during a visual inspection for evidence of corrosion or mechanical damage to the hard anodized surface of the slide tubes
• during periods of extended non-service, the landing gear slide tubes are lubricated and visually inspected for damage along their full length prior to the aircraft returning to service
• during approved pilot maintenance. the main gear slide tubes are wiped clean and lubricated and the gear carriages are completely refreshed with clean grease. 

Sources and submissions

Sources of information

The sources of information during the investigation included:

• the pilot and passengers of the accident flight
• the operator and training pilots
• the Civil Aviation Safety Authority
• De Havilland Aircraft of Canada
• Wipaire
• the maintenance organisation for VH‑OHU
• the maintenance facility that conducted the post-accident aircraft examination
• Bureau of Meteorology
• video footage from the accident flight and other photographs taken on the day of the accident.

References

Federal Aviation Administration. (2016). Human factors design standards. US Department of Transportation, United Sates Government.

Rice, E,V., & Greear, J.F. (1973). Underwater escape from helicopters. In Proceedings of the Eleventh Annual Symposium, Phoenix, AZ: Survival and Flight Equipment Association, 59-60. Cited in Brooks C. (1989) The Human Factors relating to escape and survival from helicopters ditching in water, AGRAD.

Salvendy, G., & Karwowski, W. (2021). Handbook of human factors and ergonomics (5th ed.). John Wiley & Sons, Inc, doi: 10.1002/9781119636113.

Yeh, M., Swider, C., Jin Jo, Y., & Donovan, C. (2016). Human factors considerations in the design and evaluation of flight deck displays and controls. Federal Aviation Administration, United States Government.

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 operator and training pilots
• the maintainer of VH‑OHU
• Civil Aviation Safety Authority
• De Havilland Aircraft of Canada
• Transportation Safety Board of Canada
• Wipaire
• United States National Transportation Safety Board.

Submissions were received from:

• the operator
• De Havilland Aircraft of Canada
• 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 investigation

Decisions regarding the scope of an investigation are based on many factors, including the level of safety benefit likely to be obtained from an investigation and the associated resources required. For this occurrence, a limited-scope investigation was conducted in order to produce a short investigation report, and allow for greater industry awareness of findings that affect safety and potential learning opportunities.

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

Report	Time (local)	Bearing ° T	Wind speed (kt)	Time before accident
METAR	1000	010	22	74 minutes
SPECI	1007	020	21, gusting to 32	67 minutes
METAR	1030	020	20	44 minutes
METAR	1100	010	20	14 minutes

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

Report	Time (local)	Bearing ° T	Wind speed (kt)	Time before accident
METAR	1000	360	13	74 minutes
METAR	1030	360	13	44 minutes
METAR	1100	360	10	14 minutes
METAR	1130	360	14	-16 minutes

Source: Bureau of Meteorology 

Windsock indication

Figure 6 shows VH-EYU taxiing to the runway threshold in the opposite direction but parallel to the take‑off direction. The visible opening of the orange windsock in the background indicates headwind and crosswind components for take‑off.

Figure 6: VH-EYU taxiing prior to second take‑off

Source: Supplied

Witness observations of the weather

A number of witnesses described the temperature to be ‘very hot’ (27°C) with strong and gusting winds at the time of the accident. The winds were changing in strength (15–30 kt) and direction (between runways 27 and 01) (Figure 7). A flight instructor, who was an eyewitness to the accident stated that they had cancelled a student’s flight which was to occur later in the day due to the gusty conditions. 

FlySto data from a Cessna 172

A Cessna 172 was flying nearby at the time of the accident and landed at Bacchus Marsh ALA 10 minutes after the accident. Data from the aircraft was uploaded to FlySto.[13] This data recorded the average wind from ground level up to 3,600 ft over a 40‑minute period. The wind direction varied between 262° T and 335° T and at speeds from 6–32 kt. At the time of the accident, this aircraft was located 14 km (8 NM) to the south of Bacchus Marsh ALA and had recorded a 27 kt wind from 290° T while on descent. The temperature recorded upon landing was 29°C.

A component of this data will be normal changes in wind speed and direction due to changes in altitude. For this reason, the average winds referenced in FlySto cannot be used to determine exact conditions at ground level at the time of the accident. 

Figure 7: Witness observation (red arc) and recorded data from FlySto (orange arc), showing approximate wind directions and speeds around time of VH‑EYU take‑off

Source: Google Earth, annotated by the ATSB

CCTV and witness video

CCTV recorded the pilot’s arrival at the airport, refuelling, engine run‑up and control checks, and both take‑off runs. All videos showed evidence of strong and gusting winds creating movement in nearby trees and grass. Pitot cover flags on parked aircraft and clothing of people on the apron were observed flapping in the wind. The videos also captured wind noise varying with gusts.

A gliding club located to the east of the ALA had erected a small windsock, which was observed to be moving erratically with the varying wind strength and directions. The witness video provided, showed this windsock to be a smaller commercially available item. Due to its design, it did not meet the standards[14] for wind direction indicators and therefore was not able to provide any information of wind speed. 

Recorded information

CTAF recording

CTAF recordings provided the standard radio transmissions made by the pilot. The recordings also captured the engine sounds each time a transmission was made and showed that the engine sounded normal throughout the duration of the recordings. 

The pilot sounded calm during transmission and voiced no concern with the engine or aircraft after the first rejected take‑off and subsequent return for the second take‑off. 

Aircraft data

The aircraft was not equipped with either a cockpit voice recorder or a flight data recorder, nor was it required to be. Further, there was no active flight tracking equipment or other devices fitted to the aircraft to provide parameters from the accident flight. 

CCTV

The ATSB conducted frame‑by‑frame analysis of the CCTV of the second take‑off. This analysis showed that the groundspeed of the aircraft was 42 kt when the aircraft became airborne.

Related occurrences

AO-2014-023: Cessna 150G, VH-RXM, Loss of control during initial climb, 18 February 2014, Moorabbin Airport

An instructor and student pilot were conducting a trial instructional flight. The aircraft departed with a 3‍–‍4 kt tailwind. The student was operating the aileron and elevator controls, with the instructor operating the rudder. During the initial climb, the student continued to apply back pressure to the control column resulting in a reduction in optimal airspeed, and a higher‑than‑normal aircraft nose attitude. As the instructor attempted to rectify the aircraft’s profile, the right wing dropped, and the aircraft began to descend. 

The instructor’s efforts to recover the aircraft to a normal climb attitude were not successful, and the right side of the aircraft struck the ground. The aircraft bounced, then came to a halt on its left side. The instructor and student egressed through the right door, and both sustained minor injuries. The aircraft was substantially damaged.

NTSB Docket WPR21LA255 Cessna 150L, N1972L, Collision during take‑off, 30 June 2021, Mud Lake Airport (1U2), Terreton, Jefferson County, Idaho, United States

The pilot reported that, upon landing, they saw a crop duster aircraft descending for a short base for landing on the opposite runway. The pilot initiated a go around with the flaps still extended and with a high-density altitude. The aeroplane attained an altitude of about 50 to 100 ft above ground level when the aeroplane stalled, and the left wing dropped. The pilot attempted to recover but did not have enough height before the aeroplane collided with the ground. The aeroplane nosed over and came to rest inverted. The wings and fuselage were substantially damaged. The pilot and passenger sustained serious injuries.

Safety analysis

While there was no evidence that the pilot accessed official weather forecasts on the day of the accident, the pilot may have consulted informal sources, and they were able to experience the weather at Bacchus Marsh prior to departure. Through the movement of the distant windsock, vegetation, pitot covers on parked aircraft and the clothing of people in view of CCTV and video, it was evident that strong gusting winds were present. Noise on the audio track of CCTV also showed gusts were occurring. 

This supported observations of witnesses at the airfield of the conditions throughout the day and at the time of the accident. It is almost certain the wind conditions would have also been evident to the pilot at the time of take‑off. While no weather recording equipment was available at Bacchus Marsh, the evidence available allowed for an estimate of wind varying from west to north at speeds from around 10 kt gusting to 30 kt.  

There was no evidence of problems with the aircraft. The CCTV showed the pilot conducting pre‑take‑off run-up and control checks prior to the first take‑off. Witnesses and analysis of engine sound from CTAF broadcasts from VH‑EYU confirmed that the engine sounded normal. Additionally, post‑accident examination of the aircraft found no evidence of pre‑accident damage which would have affected the flight. 

There was no stated or discernible reason for the first rejected take‑off. The pilot gave no indication of an aircraft serviceability issue in their radio calls. They did not conduct any additional engine run‑up checks or stop the aircraft to perform any exterior airframe inspection. After exiting the runway, the aircraft was taxied without delay to runway 27 for the second take‑off.

On the second take‑off, CCTV analysis showed the groundspeed of the aircraft was 42 kt when the aircraft became airborne. Based on witness observation and the Cessna 150 measurements, the ATSB estimates the aircraft likely had an airspeed of over 50 kt, marginally faster than the 48 kt stall speed of the aircraft. At that time, crosswind was likely to be around 15 kt. 

Witnesses identified and CCTV footage showed that the aircraft’s attitude was unstable after becoming airborne. This indicates that the aircraft was affected by the strong, variable and gusting headwind and crosswind components as the pilot attempted the second take‑off. These uncommanded wind‑driven movements would require constant aircraft attitude adjustments by the pilot.

The flight instructor’s observation of the steep pitch‑up and controlled lowering of the nose which occurred at around 50 ft is consistent with the pilot manipulating the controls to avoid the aircraft descending back onto the runway and to maintain a suitable airspeed and take-off profile. The second uncorrected steep pitch‑up which occurred at around 150 ft, and the subsequent dropping of the left wing and nose resulting in entry into a left incipient spin, was consistent with a fully developed stall and loss of control in flight. This, in turn, was consistent with evidence of the accident site, in which the aircraft wreckage was confined to a small area, with evidence of a high vertical impact and low forward speed. 

In this accident, it is almost certain that, after take‑off and at low level, the aircraft was subjected to a strong and gusting wind. The nature of the prevailing winds increased the likelihood of a drop in airspeed during a phase of flight where the aircraft was flown at a high angle of attack, leading to an impending stall condition. 

It is possible that the impending stall period was very short due to gust strength and the pitch‑up movement created conditions for aerodynamic stall. Further, as the airspeed at take‑off was likely only a few knots higher than the stall speed, there was minimal buffer to account for any sudden drop of wind strength. The evidence indicates that the angle of attack of the wings increased beyond the critical angle, the left wing of the aircraft aerodynamically stalled, and the aircraft entered the incipient phase of a spin. The stalling of the left wing indicates that the angle of attack on the left wing was higher than that on the right. This is likely due to control inputs to counteract a crosswind from the right.

The actions that take place when the aircraft enters a spin require the pilot to retard the throttle. The throttle position in the aircraft was found in a low power setting, which was likely due to the pilot responding to the aircraft entering the incipient phase of a spin. Because the aircraft stalled at a height of about 150 ft, there was insufficient height to recover before the aircraft collided with terrain. 

Findings

ATSB investigation report findings focus on safety factors (that is, events and conditions that increase risk). Safety factors include ‘contributing factors’ and ‘other factors that increased risk’ (that is, factors that did not meet the definition of a contributing factor for this occurrence but were still considered important to include in the report for the purpose of increasing awareness and enhancing safety). In addition ‘other findings’ may be included to provide important information about topics other than safety factors.  These findings should not be read as apportioning blame or liability to any particular organisation or individual.

From the evidence available, the following finding is made with respect to the loss of control and collision with terrain involving Cessna 150L, VH-EYU, at Bacchus Marsh aircraft landing area, Victoria, on 22 October 2024. 

Contributing factors

• It is probable that the aircraft was too slow on take‑off for the strong and gusty wind conditions and significant crosswind, meaning there was minimal buffer to manage an impending stall.  Shortly after take‑off, the aircraft stalled at a height too low to recover, resulting in a collision with terrain. 

Sources and submissions

Sources of information

The sources of information during the investigation included:

• Bacchus Marsh Aero Club
• Civil Aviation Safety Authority
• Victoria Police
• the maintenance organisation for VH-EYU
• Airservices Australia
• Bureau of Meteorology
• Peninsula Aero Club
• Oxford Aviation Academy
• TVSA Pilot Training
• witnesses
• video footage of the accident flight and other videos taken on the day of the accident
• recorded CTAF communications. 

References

Civil Aviation Safety Authority 2019, Strong and gusty winds, Civil Aviation Safety Authority, Canberra, ACT Strong and gusty winds | Flight Safety Australia

Civil Aviation Safety Authority 2020, Advisory Circular AC 61-16v1.0, Civil Aviation Safety Authority, Canberra, ACT, https://www.casa.gov.au/spin-avoidance-and-stall-recovery-training

Civil Aviation Safety Authority 2020, Part 139 (Aerodromes) Manual of Standards 2019, Civil Aviation Safety Authority, Canberra, ACT, Part139_(Aerodrome)_MOS.pdf pp 196-198.

Civil Aviation Safety Authority 2019, Rudder, ailerons, stalls and spins, Civil Aviation Safety Authority, Canberra, ACT Rudder, ailerons, stalls and spins | Flight Safety Australia

Civil Aviation Safety Authority 2022, Stalls in the circuit, Civil Aviation Safety Authority, Canberra, ACT Stalls in the circuit | Flight Safety Australia 

Civil Aviation Safety Authority 2022, Advisory Circular AC 91-02v1.2, Civil Aviation Safety Authority, Canberra, ACT https://www.casa.gov.au/guidelines-aeroplanes-mtow-not-exceeding-5-700-kg-suitable-places-take-and-land pp21-22.

Civil Aviation Safety Authority 2024, AvSafety: Preventing a stall at low level, Civil Aviation Safety Authority, Canberra, ACT, Preventing a stall at low level

Federal Aviation Administration 2021, Airplane Flying Handbook (FAA-H-8083-3C), Federal Aviation Administration, Washington DC Airplane Flying Handbook 

National Transportation Safety Board 2015, NTSB Safety Alert 19 / Prevent Aerodynamic Stalls at Low Altitude, National Transportation Safety Board, Washington DC NTSB Safety Alert 19 / Prevent Aerodynamic Stalls at Low Altitude

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 Civil Aviation Safety Authority
• the Bacchus Marsh Aero Club
• the National Transportation Safety Board.

Any submissions from those parties were reviewed and, where considered appropriate, the text of the draft 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 

The day before the accident

On 31 August 2024, the pilot of a Cessna U206F, registered VH-TDQ and operated by Fly Esperance, departed Esperance Airport, Western Australia (WA). The aircraft was ferried to a private aircraft landing area (ALA), 50 NM (93 km) north‑west of Esperance to conduct a non‑scheduled air transport flight to a private ALA about 21 NM (39 km) south‑east of Moora. The 3 passengers and pilot would spend the night at the property with the intention of returning the following day. 

On the first arrival at the destination ALA, the pilot made an approach to the westerly runway and configured the aircraft with 20° flap[1] for landing. During the first landing attempt, the aircraft bounced and the pilot conducted a go-around.[2] On the second landing attempt, the pilot configured the aircraft in a 40° full-flap configuration and landed without incident.

Accident flight

On the morning of 1 September 2024, the customers requested two 15-minute local flights for the family members they had been visiting. The pilot consulted the operator’s chief pilot by phone who approved the flights. The pilot then collected the passenger’s weights and assigned them to each flight.

The pilot gathered the passengers of both flights together and conducted a group safety briefing before the passengers on the first flight boarded the aircraft. With 5 passengers on board, the pilot took off on the western runway and departed about 1050 local time, tracked to the north before returning to the ALA a short time later (Figure 1). About 2 NM (3.7 km) north and within sight of the ALA, the pilot assessed that the aircraft was too high and conducted a left orbit to reduce height. 

The pilot reported they were advised the previous day by the local agricultural pilots to utilise the uphill slope for landing using the easterly runway and recalled, as there were no other aircraft in the vicinity, directly joining the base leg of the circuit for the easterly runway. They observed a 75 kt airspeed on final approach before configuring the aircraft for a full flap final approach for landing.

Figure 1: VH-TDQ flight track 

Source: Google Earth, annotated by the ATSB

The pilot landed the aircraft about 80 m (Figure 2) past the end of the easterly runway and bounced twice before they applied full power and commenced a go-around. The pilot was unable to recall their airspeed at the time of the flap reduction, however reported that the aircraft had probably dissipated a considerable amount of speed during the bounces prior to initiating a go‑around. As the aircraft began the initial climb the pilot reduced the flap setting, unknowingly mis-selecting the 10° setting.

Figure 2: Aircraft landing area

Source: Google Earth, annotated by the ATSB

As the flap retracted, the aircraft lost height and the pilot was unable to maintain control. The aircraft dropped the right wing and the right wingtip grazed the ground in the adjacent field. 

The right wingtip then raised above the crop height, however the propeller and landing gear remained partially in the crop (Figure 3) increasing drag and reducing speed. Shortly after, the aircraft touched down on its landing gear with the propeller making full contact with the crop and stopping the engine. The aircraft came to a stop upright, about 250 m from the runway, with the flaps extended in the 10° position. The pilot recalled at this point they switched off the aircraft’s fuel and electrics.

Figure 3: Aircraft landing gear marks in field adjacent to the runway

Source: Fly WA Group, annotated by the ATSB

The pilot then checked on the welfare of the passengers and as a precaution, instructed them to evacuate the aircraft.

The pilot successfully egressed the front seat and middle-row passengers through the forward left cabin door. They then proceeded to the right side of the aircraft to assist the 2 passengers in the rear seats egress through the right-side cargo doors. 

On approaching the rear of the aircraft, the pilot observed that the extended flap had blocked the forward half of the cargo door and therefore believed they would not be able to open the rear half of the cargo emergency exit. After an unsuccessful attempt to retract the flaps, the pilot reported they were no longer operational. They did not attempt to open the rear cargo door further and instructed the rear seat passengers, an older person and young child, to egress over the middle row seat and then through the pilot’s forward left cabin door. 

The aircraft received minor damage to the right fibreglass wingtip and aileron. No injuries were reported, and all passengers successfully evacuated the aircraft. 

Context

Pilot information

The pilot held a commercial pilot licence (aeroplane), issued in August 2016. At the time of the accident, the pilot had about 390 hours of total flying experience, with 134.4 hours as pilot in command and about 30 hours on the Cessna 206. The pilot had operated for 49.4 hours in the last 90 days and held a current class 1 medical certificate that was valid until 29 July 2025.

The pilot was employed by the operator in June 2024 and had flown scenic flights from Jandakot, Western Australia (WA), before gaining full time employment with the same operator to conduct flights from the operator’s Esperance base, where the pilot had been located since August 2024.

During their initial employment with the operator, the pilot received about 13 hours of line training. The training included: 

• emergency procedures
• remote airfields
• short fields
• maximum all-up weight flight. 

The pilot’s logbook indicated a check flight was conducted by the operator’s chief pilot on 19 July 2024. They then began commercial flights for the operator about 1 week later. 

Although they had held a commercial licence since 2016, this was the pilot’s first aviation employment, having completed training and private flying before gaining employment with the operator. The logbook also indicated that prior to the pilot’s employment with the operator, limited flying was conducted, with a total of 4.2 hours flown in the 12 months before commencing with the operator.

Aircraft information

General information

The Cessna U206F is a single piston engine, high winged, 6-seat, unpressurised aircraft with fixed landing gear. The aircraft was powered by a Teledyne Continental IO-520 engine. 

VH-TDQ was manufactured in the United States in 1975 and first registered in Australia in August 1975. Fly Esperance became the registration holder on 29 April 2023. 

Cessna 206 variants

The Cessna 206 was produced between 1963 and 1986. In 1998, Cessna restarted production of the Cessna 206 and the aircraft remains in production.

The original model, named the Cessna 206 Super Skywagon, was produced between 1963 and 1965 and featured the rear right side double cargo doors. Subsequent models (Table 1) were also manufactured with the double cargo doors and included numerous different models between 1963 and 1986. Cessna aircraft company halted production of 206 aircraft between 1987 and 1997. Production resumed in 1998 with the current model 206H.

Table 1: Cessna 206 models manufactured with the double cargo doors

Year	Cessna 206 model name
1963/65	206 Super Skywagon
1966*	U206A 206 Super Skywagon
1967*	U206B Super Skywagon
1968*	U206C Super Skywagon
1969*	U206D Super Skywagon
1970/71*	U206E Skywagon 206/Stationair
1972-76*	U206F Stationair
1977-86*	U206G Stationair
1998-current*	206H Stationair

* Indicates model was also manufactured with a turbo variation

Aircraft flaps

The Cessna 206 has an electrically‑controlled flap system. This requires the battery master[3] to be on and also requires the cargo doors to be completely closed. Closed cargo doors trigger a micro‑switch, located in the doorframe, which completes the electrical circuit and then allows flap movement. As the Cessna 206 flaps extend across the closed forward cargo door (see Cabin layout and exits), this provides a protection so the flaps cannot be inadvertantly extended into an open cargo door and damage the aircraft. 

The flap control lever in the Cessna U206F is located on the pilot’s right side (Figure 4) and is clearly visible from the pilot’s seat. The lever allows the flaps to be set in any position between 0° (flaps fully retracted) and 40° (full-flap extension) with an adjacent placard marking the flap position. 

The pilot described on numerous occasions during an interview with the ATSB ‘hitting or flicking’ the flap selector lever, identifying that the flap selection was sometimes made without the time taken to confirm the flap selection was in the correct position. 

The operator’s chief pilot reported they had not observed the pilot manipulating the lever like this during the 13 hours of in command under supervision (ICUS) flying they completed with the pilot.

Figure 4: Cessna U206F cockpit

Source: Pilot, annotated by the ATSB

Cabin layout and exits

VH-TDQ was operated in a 6-person configuration with 2 front row (pilot) seats, 2 middle row seats and 2 rear seats (Figure 5).

Figure 5: Cessna 206 standard cabin seating configuration 

Source: TSB investigation report A18W0129, adapted by ATSB to match occurrence aircraft 

VH-TDQ included 2 emergency exits, the pilot’s forward left cabin door and a double ‘clam shell’ style cargo door located at the rear right of the aircraft cabin. Passengers seated in the middle row seats are able to access the pilot’s forward left door when the pilot’s seat is moved into a forward position. The forward part of the cargo door overlaps the rear cargo door as a preventative measure to stop the rear door (rear hinged) from opening in flight and damaging the aircraft. The rear cargo door cannot be opened independently of the front cargo door.

Wing flap extension greater than 10° results in the flap blocking the forward part of the cargo door (Figure 6) and restricts the opening to about 8 cm. When the aircraft wing flaps remain extended, the forward cargo door must be opened as far as possible to then allow the rear door to be opened. Further detail is discussed below in Cessna 206 rear passenger emergency egress.

Figure 6: Cessna 206H showing extended flap blocking forward cargo door

Source: ATSB

Meteorological information

The pilot reported that they assessed the local weather conditions via their NAIPS[4] account on the morning of the occurrence flight and recalled that the predicted wind at the aircraft landing area (ALA) was calm.

Bureau of Meteorology data from the nearest recorded locations at the time of the occurrence indicated local winds between 12–14 kt in a south-westerly direction (Figure 7).

Figure 7: Weather reporting locations in relation to the private aircraft landing area

Source: Google Earth, annotated by the ATSB

Aeroplane landing area information

The ALA was on privately‑owned farming land and was regularly used by agricultural pilots to conduct spraying of crops in the local area. The elevation of the ALA was about 800 ft above mean sea level (AMSL) and the runway orientation was about 120/300°[5] and had a gradual slope that increased towards the east, rising about 40 ft over the length of the runway. It was surrounded by waist-high crops, had a gravel surface and a useable length of about 570 m. The ALA did not have a windsock, nor was there a wind indicating device located nearby.

Prior to operating at the ALA, the operator spoke with the landowners to gain understanding of the recent landing area conditions, as they had not flown to the location previously. They were put in contact with the agricultural pilots who had been recently operating from the field and received a landing area condition report. The operator assessed that the area was suitable for the Cessna 206.

Standard circuit pattern

A circuit is the specified path to be flown by aircraft operating in the vicinity of an aerodrome (Figure 8). It comprises of upwind, crosswind, downwind, base and final approach legs.

Figure 8: Standard left-hand circuit pattern

Source: SKYbrary, modified by the ATSB

The Civil Aviation Safety Authority (CASA) Advisory Circular AC 91-10v1.3 advised pilots that joining a base leg of a circuit is not a standard procedure. Stating:

CASA recommends that pilots join the circuit on either the crosswind (midfield) or downwind leg. However, pilots who choose to join on base leg should only do so if they have familiarised themselves with the weather conditions to be expected and aerodrome serviceability.

The AC advised that pilots who join the base leg of the circuit increase the risk of a downwind landing and may conflict with other traffic using the into-wind runway. It also stated that late go‑around decisions and landings on a closed runway were more common.

Recorded data

Flight Radar 24 data[6] indicated that when the pilot commenced the left-hand orbit approaching the ALA, that the aircraft was about 2,000 ft AMSL and at the conclusion of the orbit, as the aircraft joined the base leg, it remained at about 2,000 ft AMSL, about 1,200 ft above the ALA. As the aircraft became established on final approach for the easterly runway, the aircraft height was recorded as 1,500 ft AMSL, 700 ft above the ALA and 1.6 NM from the runway threshold.

Flight Radar 24 showed that the aircraft’s ground speed had slowed to around 75 kt on the base leg of the approach to landing. As the aircraft turned onto final approach the ground speed increased, reaching 92 kt and indicated about 85 kt ground speed at the last data recording on short final for the easterly runway.

Video footage from a passenger seated in the rear left seat was obtained by the ATSB. Video footage showed that the initial touchdown point (Figure 2) was about 80 m past the runway threshold, reducing the remaining runway length to about 490 m. The footage also showed that during the go-round, the aircraft began to lose height shortly after the flaps were retracted and that this was followed by a roll to the right.

Operator’s internal review

On the day of the accident, the operator’s chief pilot attended the accident site, gathered images, reviewed the aircraft damage and debriefed with the pilot.

The chief pilot advised that post‑accident aircraft testing was carried out later that day and the flaps were tested and found to be operational.

From the pilot’s report, flight data and images gathered, the operator completed a detailed internal review of the accident. A summary of the findings included:

• the aircraft’s approach became unstable due to the excess speed

• the speed was more appropriate for a 20° flap setting

• the excess speed likely resulted in the aircraft ‘floating’ and landing long on the runway

• after an initial bounce on landing the pilot continued the approach to land before a second bounce

• inadvertent incorrect flap setting reduced the aircraft climb performance.

Cessna 206 procedures

Unstable approach procedure

The Cessna 206F aircraft flight manual (AFM) advised pilots that the approach speed for a full‑flap, short field landing should be 75 mph (65 kt).

The operator’s exposition stated that the airspeed for the stabilised approach criteria below 1,000 ft is not more than VREF[7] (65 kt) + 5 kt.

Data from Flight Radar 24 showed the aircraft ground speed had slowed to 75 kt on the base leg of the circuit, before increasing to 92 kt ground speed on final approach. The pilot reported the airspeed on final was 75 kt prior to selecting full flap for the landing. 

Go-around procedure 

The Cessna 206F AFM emergency section provided the balked landing (go-around) procedure:

Power – Full throttle and 2850 RPM

Wing Flaps – Retract to 20°

Airspeed 90 MPH (78 kt)

Wing flaps – Retract slowly

Cowl flaps – Open.

Additionally, the AFM provided further detail when conducting a go-around:

In a go-around climb, the wing flap setting should be reduced to 20° immediately after full power is applied. After all obstacles are cleared and once a safe altitude and airspeed are obtained, the wing flaps should only then be retracted further.

On initiating the go-around the pilot inadvertently reduced flap to the 10° setting resulting in a reduction of lift produced by the wing.

Ditching and forced landing procedure

The Cessna 206 ditching and forced landing procedure described in the AFM instructed pilots to configure the aircraft to the full-flap position so as to impact with water or terrain at the slowest possible speed. This procedure did not mention the retraction of the flaps on completion of the ditching or forced landing

Operator’s passenger safety briefing 

The operator’s exposition stated that pilots shall brief passengers about the following matters and confirm they have an understanding:

• the pilot in command is responsible for passenger safety

• safety instructions and directions from the pilot in command must be followed

• smoking tobacco, electronic cigarettes or any other substance on the aircraft is prohibited

• when seatbelts are to be worn, and how to use them

• seat backs are to be upright during take-off and landing

• how and when to adopt the brace position

• how to approach and move away from the aircraft

• entry and egress from the aircraft, including in emergency situations

• where and how to stow baggage and personal effects

• use of survival equipment / ELT as appropriate

• use of life jackets and life rafts (if carried for the operation) and that life jackets must not be inflated inside the aircraft

• restriction on the use of PEDs (personal electronic devices) and when they can be used

• communications and headset use

• if the passenger is in a flight crew seat, the requirement to ensure controls are not manipulated or interfered with

• the location of the Safety Briefing Card located at each seat.

The pilot recalled that they conducted a group briefing of the passengers prior to the first planned local area flight, with the intention of providing the passengers for the second flight an additional briefing before they boarded. 

The pilot reported they briefed the passengers on the aircraft’s seatbelts, location of the fire extinguisher, life jackets, first-aid kit and provided instruction to the front seat passenger regarding remaining clear of the flight controls. They also explained the use of both the forward left cabin door and the double cargo emergency exit doors, highlighting the red handle to open the rear cargo door. The pilot did not indicate that the passengers were briefed on actions in the event of the emergency exit being obstructed.

The adult passenger seated in the rear seat recalled seeing the handle for the forward cargo door, however they were unsure if the rear cargo door had a handle. As discussed (see Cessna 206 rear passenger emergency egress), the emergency handle is not readily visible from the rear seats in older Cessna 206 aircraft when the cargo doors are closed.

Regulatory information on emergency egress

The Cessna 206 was first certified in 1963 by the United States (US) Federal Aviation Administration (FAA). FAA regulation 14 CFR 23.2315 stated that an aeroplane is designed to: 

(a)(2) Have means of egress (openings, exits, or emergency exits), that can be readily located and opened from the inside and outside. The means of opening must be simple and obvious and marked inside and outside the airplane.

There have been a number of revisions made to this FAA design standard over the years. However, once an aircraft has been certified, the design standard under which it was certified continues to apply.

Part 90 of Civil Aviation Safety Regulations (CASR) 1998 - Additional airworthiness requirements Subpart 90.005 sets out the airworthiness requirements for an aircraft that are in addition to the type certification basis for the aircraft.

Under regulation 90.020 of CASR 1998, the Manual of Standards (MOS) sets out the additional airworthiness standards required for CASR Part 90 including, access to emergency exits.

Part 90 of the MOS stated that the minimum opening of an emergency exit must be unobstructed at all times. 

CASR 90.135 stated that each passenger must have access to at least one exit that meets the requirements prescribed by Part 90 of the MOS.

Cessna 206 rear passenger emergency egress

Background

When configured as a 6 seat-passenger aircraft, the cargo door provided the closest emergency exit for passengers seated in the rear seats and an alternate exit if the pilot’s left front cabin door became obstructed.

As discussed above in Aircraft information, when the flaps are extended, they physically block the forward cargo door from being opened beyond about 8 cm, not enabling egress.

The internal forward cargo door handle has 3 positions:

• when the lever is horizontal (with the lever facing forward), the door is locked
• turned clockwise 90° to the vertical position, the door is closed
• turned clockwise another 30°, the door is opened.

With the forward door handle in the locked position the door is unable to be opened from the outside. The pilot reported that the rear seat passengers attempted to open the forward cargo door, however due to the extended flap were unable to push the door open. As the passengers were unaware of the location of the rear door handle (see Operator’s passenger safety briefing), no attempt was made to open the rear cargo door.

For the earlier models (pre-H model), including VH-TDQ, the rear door handle is a red lever (Figure 9) located in the leading edge of the rear door, which is rotated forward (to horizontal position) to open. When the forward cargo door is blocked by the flaps and the rear door handle is in the horizontal position, the rear door can only be partly opened as the horizontal handle cannot pass the forward door. The handle must then be re-stowed in the vertical position to allow the rear cargo door to pass the obstructed forward cargo door. In an emergency situation, this can and has delayed or prevented egress from the aircraft. Once the forward cargo door is slightly opened, it is possible to access the rear door handle from outside the aircraft and open the door using this process.

The pilot advised the ATSB they were aware that the forward cargo door became blocked with the flaps in an extended position. They also advised that they were aware of the requirement to open the forward cargo door before the rear door could be opened and understood the operation of both the cargo door handles. However, the pilot believed that when the flaps remained extended and blocked the forward cargo door, that the rear cargo door was unable to be opened. 

The operator’s chief pilot also reported that if the forward cargo door was blocked by the flap that passengers would be forced to egress the aircraft via the pilot’s forward left cabin door, which would be difficult for passengers seated in the rear seats.

Figure 9: Cessna U206G Cargo door

Source: TSB investigation report A18W0129, annotated by the ATSB

Cessna 206F aircraft flight manual

The emergency section of the aircraft’s flight manual contained instructions for the operation of the cargo door emergency exit which stated:

If it is necessary to use the cargo door as an emergency exit and the wing flaps are not extended, open the forward door and exit. If the wing flaps are extended, open the door in accordance with the instructions on the placard [see Figure 10] which is located on the forward cargo door.

Cessna cargo door latch service bulletin

In 1991, to assist in operating the rear cargo door from inside the aeroplane during night operations, Cessna issued Service Bulletin SEB 91-4 Cargo door latch improvement. The service bulletin recommended the installation of a return spring in the rear cargo door handle, automatically returning the handle to the closed position after opening. This assisted the rear cargo door to move freely past the blocked forward cargo door.

The service bulletin was not mandatory and was not installed on VH-TDQ.

Placard alternative

Prior to the service bulletin, due to demonstrated difficulties opening the cargo doors when the aircraft flaps remained extended during emergency situations in both Australia and overseas, the Civil Aviation Authority (CAA)[8] issued Airworthiness Directive 206/47 in 1988 that required the improvement of existing emergency exit placards for Cessna 206 aircraft in Australia (Figure 10). The placard drew attention via bold letters to step 3, to ensure the rear door handle was returned to the original position (vertical) before attempting to open the rear door (step 4). 

In 1991, when Cessna issued Service Bulletin SEB 91-4, the CAA issued Airworthiness Directive Cessna 206/47 amendment 2, which allowed SEB 91-4 to be an alternate means of compliance to the CAA emergency exit placarding. 

In 2011, CASA subsequently issued Airworthiness Directive Cessna 206/47 amendment 3, which clarified which Cessna 206 models the airworthiness directive applied to. This was due to SEB 91‑4 being incorporated by the manufacturer in some newer models, and because other models did not have the cargo door. SEB 91-4 remained as an alternate means of compliance. 

The placard was installed on VH-TDQ.

Figure 10: Forward cargo door placard 

Source: CASA Airworthiness Directive 206/47 Amendment 3

Canadian type certificate and airworthiness directive

In 1998, Cessna resumed manufacturing the 206 model aircraft with the 206H. The H model featured larger and more visible cargo door handles and incorporated SEB 91-4 for the return spring in the rear cargo door handle into the design. The forward cargo door remained blocked with flaps extended on this variant.

The 206H was certified under the US Federal Aviation Regulations 23.807. Transport Canada (TC) disagreed with the certification, stating that:

The design of the doors did not satisfy the (FAA) certification requirements that the method of opening the doors be simple and obvious and the door be readily opened, even in darkness.

As a result, in 2000 TC issued a type certificate reducing the Cessna 206H occupancy to 5 passengers.

In 2019, the Transport Safety Board of Canada issued safety advisory A18W0129-D1-A1 that stated that between 1999 and 2003, TC, the FAA and Cessna, had worked together in an effort to come up with a design change that could be applied to the Cessna 206H, which could also be used to retrofit older models of the Cessna 206 fleet. However, the matter remained unresolved and no acceptable solution was found.

In 2020 TC issued Airworthiness Directive CF-2020-10, applicable to Cessna 206 models that featured the double cargo door, stating that:

Earlier versions of the model 206 registered in Canada that feature the cargo doors have not been subject to occupancy limits, other limitations or corrective action requirements related to the cargo doors. These earlier versions of the model 206 have continued to operate in Canada without corrective or mitigating action despite the fact that the method of opening the cargo doors is essentially the same as the method for the 206H and T206H models. There is objective evidence that difficulty opening the cargo doors has contributed to fatalities during accidents in Canada involving the model 206.

The AD CF-2020-10 limited earlier model Cessna 206 to 5 occupants and required the removal of one of the middle row seats if either rear seat was to be occupied. The removal of a middle row seat provided access for passengers seated in the rear seats to the pilot’s forward left cabin door (Figure 11) for evacuation in the event the rear cargo door could not be opened quickly enough for egress. The AD also clearly stated that the vacant space left by the removal of a middle row seat must not be used for storage of cargo or baggage. 

Figure 11: Seating configuration for Canadian Cessna 206  

Source: TSB investigation report A18W0129, adapted to indicate seat removal, annotated by the ATSB

The AD also provided an alternative means of compliance through a supplemental type certificate (STC),[9] STC SA1470GL, for the installation of an additional door, on the forward right side of the cabin and was applicable to all models of the Cessna 206. This commercially available alternative means of compliance allowed Canadian registered aircraft to remain in the original 6‑seat configuration. If installed, the additional door provided immediate egress option for the passenger in the front right seat and an additional emergency egress for passengers seated in the middle row.

Australian acceptance of type certificate and supplemental type certificates

Since 1990 CASA has provided for the automatic acceptance of foreign aircraft type certificates and STC’s issued by a national aviation authority of recognised countries[10] including European Union Aviation Safety Agency (EASA).

CASA has accepted the type certificate of the national aviation authority issuing state (United States), for the following models of the Cessna 206: 206, P206, P206A, P206B, P206C, P206E, U206, U206A, 206H, U206B, U206C, U206D, U206E, U206F, U206G, T206H, TU206A, TU206C and TU206G (P206 models are not manufactured with the double cargo door).

ATSB safety recommendation

In 2020, after ATSB investigation (

), into an accident involving a Cessna U206G on Fraser Island, Queensland, the ATSB issued CASA with safety recommendation AO-2020-010-SR-018 recommending that CASA take safety action to address the certification basis for the design of the cabin doors in the Cessna 206, as wing extension beyond 10° will block the forward portion of the rear double cargo door, significantly hampering emergency egress.

In response CASA issued Airworthiness Bulletin 52‑006 in 2021, with a subsequent reissue in 2025. The bulletin advised pilots and operators of the impeded access from the cargo door emergency exit with the flaps extended and made recommendations that:

• Pilots should be aware that lowering the flaps may obstruct this exit and significantly increase the difficulty of opening the forward door section of the rear cargo door. All passenger pre-flight briefings should include a practical demonstration of how to open and egress the aircraft through a flap obstructed cargo door. This will require a demonstration with flaps lowered to at least 20 degrees to demonstrate the condition. Care should be taken to not damage the flap or door during this demonstration.

• Additionally, in the event that an emergency landing or water ditching is required, pilots should consider retracting the flaps if possible after the emergency landing or if operationally feasible, limit the amount of flap extension to a maximum of 10 degrees. This would of course be a judgement made by the pilot in command based on operational factors, severity of the emergency/damage to aircraft and if there are occupants seated in the rear of the aircraft.

• It is strongly recommended that registered operators and operators of affected Cessna 206, T206, TU206 and U206 aircraft series, review TC AD CF-2020-10 and give due consideration to compliance with the intent of this document, however compliance is not mandatory under CASR Part 39, because the AD is not from the state of design.

The ATSB investigation also issued Cessna a safety recommendation AO-2020-010-SR-017. The safety recommendation was to address the concern that although the Cessna 206 AFM ditching procedure required pilots to extend the flaps to the full-flap position, which resulted in a slower landing speed, this significantly impeded the emergency egress via the cargo door emergency exit and there was no warning in the AFM of the additional risk. In response, Cessna provided a temporary revision to only the Cessna 206H model AFM, providing a warning stating:

FLAP POSITIONS OF 10 DEGREES OR GREATER MAY IMPEDE EVACUATION FROM THE CARGO DOOR. FAILURE TO ADHERE TO ALL SAFETY INSTRUCTIONS CAN RESULT IN BODILY INJURY OR DEATH. 

Cessna advised the warning would be incorporated into the next revision of the Cessna 206H AFM and a placard, with the same warning would be produced for older Cessna 206 models that featured the double cargo doors. In November 2024, mandatory service bulletin SEB-11-05 was released for all Cessna 206, and U206 models prior to the 206H, for the installation of the placard on the cockpit instrument panel or another location directly visible to the pilot. The service bulletin had not been released at the time of the occurrence. 

Cessna 206 modifications to allow cargo door to open with flaps extended

Since the release of AD CF-2020-10, in 2020 TC also approved STC SA20-34 which allows the forward cargo door corner to be hinged (Figure 12). This allows the door to fold on a hinge and fully open with flap extended in any position and therefore creating no restriction to the rear cargo door.

Figure 12: Cessna split cargo door

Source: Coast Dog Aviation, annotated by the ATSB

Additionally, on 2 May 2023, TC approved STC SA23-21 to provide an additional handle that is installed internally on the forward cargo door. The handle is accessible to the rear seat passengers, which, when activated jettisons the front cargo door from the aircraft. The removal of the door provided egress to the middle row occupants when flaps remained extended. The release of the door from the aircraft also improved visibility of the rear cargo door handle and simplified opening the rear cargo door for occupants seated in the rear seats.

Both STC SA20-34 and STC SA23-21 are approved as alternative means of compliance to TC CF-2020-10 and allowed Canadian registered aircraft to retain the 6 seat configuration.

VH-TDQ was not modified with the approved STC’s for the cargo door and a second forward right side door was not fitted (STC SA1470GL) and the aircraft remained in the original 6 seat configuration.

Related occurrences 

ATSB conducted a search of aviation investigation databases and other sources to identify accidents involving Cessna 206 aircraft (Appendix 1 – Cessna 206 occurrences). This search specifically looked at accidents where the impact was considered likely survivable, however where difficulties opening the cargo door resulted in significant delays during the emergency egress, or the cargo door had not been opened. 

The ATSB identified 10 occurrences that included 23 fatalities between 1985 and 2020 globally. Highlighted during the search were multiple occurrences of Cessna 206 accidents that involved fatalities when Cessna 206 aircraft were equipped with floats and operated on water. 

In March 1999, near Pitt Island, New Zealand, a Cessna 206 had an engine failure and ditched in the sea. The pilot was aware of the issue with the extended flap blocking the cargo doors and ditched the aircraft with the flaps retracted. Consequently, all the occupants escaped from the aircraft and swam to shore (New Zealand Transport Accident Investigation Commission, investigation report 99‑001) .

In January 2020, during a landing at a beach landing area on Fraser Island, Queensland, the Cessna U206G aircraft veered significantly to the left. Once airborne it was identified that the rudder was jammed in the full‑left position and the pilot had to apply full opposite aileron to maintain control. Shortly after, possibly due to fuel starvation the aircraft collided with water. Unable to open the pilot’s door the trainee pilot kicked the cargo door to force it open past the extended flap (ATSB investigation AO-2020-010).

Safety analysis

Introduction

On the morning of 1 September 2024, the pilot of a Cessna U206F, registered VH-TDQ, departed a private aircraft landing area (ALA), 21 NM (39 km) southeast of Moora, Western Australia (WA) with 5 passengers on board for a 15-minute local area flight. On return to the ALA the pilot conducted a full flap landing on the easterly runway and bounced twice. The pilot then commenced a go-around, however as the aircraft began the initial climb, the pilot inadvertently reduced the flap setting 10°. The aircraft lost height and the right wing dropped, making contact with terrain, removing the right wing tip and damaging the right aileron. The aircraft then lost speed and landed upright in a field adjacent to the runway. 

Unstable approach

As the pilot approached the ALA and was about 2 NM (3.7 km) north, they assessed that the aircraft was too high and elected to conduct a left orbit with the intention of reducing the aircraft’s height. However, no reduction in height was recorded during the orbit. 

The pilot conducted a non-standard approach to the easterly runway by joining the circuit on a base leg. This resulted in a reduction of available time for the pilot to assess the vertical descent profile effectively and likely contributed to the pilot mis-managing the short field landing with additional speed and height on the final approach.

Contributing factor The pilot conducted a non-standard base leg join to the circuit for landing. This reduced the time available for the pilot to configure the aircraft, reduce the airspeed and prepare for a short field landing.

A combination of additional speed on final approach, the effects of a tailwind and the aircraft in the full-flap landing configuration, likely extended the aircraft’s flare. This resulted in the aircraft landing past the intended touchdown point. This also contributed to the aircraft bouncing on landing and further reduced the runway available to safely stop and likely resulted in the pilot‘s decision to go-around.

Contributing factor Due to excessive speed on approach for a full flap, short field landing, the aircraft landed long and bounced twice.

Go-around

After the aircraft bounced a second time, the pilot commenced a go-around and applied full power to climb away. As the aircraft increased speed and began the climb out, the pilot intended to reduce the flap setting to 20° to reduce drag, but inadvertently reduced the flap setting to 10°. This resulted in a flap configuration below the prescribed setting for the aircraft’s balked landing (go‑around) procedure. 

The aircraft had not achieved the required airspeed for the lower than intended flap setting and this developed into a lack of sufficient lift and a loss of climb performance. This resulted in the aircraft losing height and directional control which caused right wingtip contact with the ground. 

Contributing factor The pilot mis-selected the flap setting during the attempted go-around. As a result, the aircraft could not achieve adequate climb performance.

Passenger evacuation

After the aircraft came to a stop, the pilot instructed the passengers to evacuate. The front seat passenger and middle row passengers were able to egress through the pilot’s forward left cabin door. However, due to the flaps remaining extended in the 10° position, the forward half of the right-side cargo door (emergency exit) could not be fully opened. While the rear cargo door could have been opened (either from the inside or the outside), the blocking of the forward door increased the difficulty of opening the rear cargo door and caused confusion about how to evacuate the rear seat passengers.

From the inside, the rear door handle was not easily visible to passengers in the rear seats due to its obscured position and location relative to the middle row seats and the forward cargo door only able to be partially opened. Although the pilot reported providing a safety briefing to the passengers, and an aircraft placard provided instructions for the operation of the cargo door emergency exit when the flaps remained in an extended position, the adult rear seat passenger was not fully aware of the location of the rear cargo door handle.

Due to the forward cargo door being blocked by the extended wing flaps, and a rear door handle that was not easily accessible to the pilot outside the aircraft and not easily visible to passengers in the rear seats, the 2 rear seat passengers could not enact the opening of the rear emergency exit, and ultimately were required to climb over the middle row seats and egressed via the pilot’s forward left cabin door.

While this delayed a timely evacuation, in this case the rear passengers were an older adult and a young child but both capable of climbing over seats, and the pilot was able to assist from outside the aircraft. However, in emergency situations where the passengers may be less able-bodied or the pilot is incapacitated or unable to assist, the functioning of aircraft emergency exit systems must be quickly apparent and passengers must have enough awareness of their operation to ensure timely and unassisted evacuation.

Other factor that increased risk With the flaps extended in the 10° position when the aircraft came to rest blocking the full opening of the forward cargo door, the rear seat passengers were unable to open the rear cargo door to enable an emergency exit.

In this case, there was an additional chance to evacuate via the rear emergency exit as the pilot could walk around to the outside of that exit.

As pilots of small passenger aircraft are responsible for the emergency egress of passengers, it is essential that the pilot has a full understanding of the operation of the emergency exits. Instructions for the operation of cargo door emergency exit when the flaps remained in an extended position were available on an aircraft placard.

The pilot understood that the operation of the rear cargo door was reliant on the forward door being open, and was also aware that extended flaps may block the forward cargo door. However, the pilot was unaware the rear cargo door could be opened after the forward cargo door had been made ajar (blocked by flaps). As a result, the pilot first tried (unsuccessfully) to retract the flaps, even though this was not required to open the rear cargo door. When that failed, likely due to the door remaining ajar preventing the micro‑switch activation of power to the flap system as designed, the pilot instructed the occupants to egress via the forward cargo doors over the middle row seats.

In this case, as the aircraft was not on fire nor floating on water, this lack of knowledge did not result in a worse consequence. However, in other circumstances, the inability to egress rear seat passengers from the rear emergency exit could have serious consequences.

Other factor that increased risk The pilot was unaware that the rear cargo door on the Cessna 206 could be opened from the outside when the front cargo door was blocked by the extended flaps.

Previous ATSB and international investigations have highlighted the difficulty occupants of the Cessna 206 face egressing via the cargo door emergency exit when the aircraft flaps remain extended. While it is possible to open the rear cargo door from outside the aircraft when the forward door is blocked by the extended flaps, without training or demonstration the process is not simple or obvious. The pilot had limited experience on the aircraft type and was unaware of the process. 

Although CASA Airworthiness Bulletin 52-006 advised operators to brief passengers on emergency egress with flaps blocking the forward cargo emergency exit, the chief pilot also was unaware it was possible to open the rear cargo door when the forward cargo door was blocked by the flaps. This meant that they were unable to educate company pilots on the additional complexity operating the rear cargo door with flaps extended.

Although the company operations manual stated that pilots were required to brief passengers entry and egress from the aircraft, including in emergency situations, the operator did not provide further documentation to pilots that the passenger briefing should also demonstrate the cargo door operation with the flaps extended as recommended by CASA Airworthiness Bulletin 52-006.

The knowledge involved to demonstrate this would have provided the pilot with the correct understanding of the operation of those doors as was needed in this case. Further, had such a demonstration been conducted, it is likely that passengers seated in the rear of the aircraft would have also been aware of the location of the rear cargo door handle and process when the flaps remained extended. 

Passenger briefings therefore lacked in this regard, and in an emergency event where passengers were required to open the rear cargo/emergency doors quickly with the flaps extended, this increased the risk that the rear seat passengers would not be able to egress at all or quickly enough to escape injury.

Other factor that increased risk The operator’s pre-flight passenger briefing did not include the demonstration of, and pilots were not trained how to operate, the emergency exit via the cargo door with the flaps extended.  (Safety Issue)

Safety advisory notice The Australian Transport Safety Bureau advises Cessna 206 pilots and operators that due to the difficulties occupants have encountered egressing the rear cargo door as identified in several transport safety investigations, to ensure they are familiar with CASA‑issued Airworthiness Bulletin 52‑006, and ensure passengers are provided with a thorough safety briefing demonstrating the cargo door emergency egress when the wing flaps remain in the extended position.

Cessna 206 emergency egress

The Cessna 206 cargo door emergency exit has featured in numerous transport safety investigations across the world. To date, Transport Canada remains the only regulatory body that has made significant changes that improve the ease of use during an emergency. 

Transport Canada’s decision to issue an amended type certificate for the Cessna 206H when production was restarted, limited the aircraft to 5 occupants, with the required removal of a middle row seat if either rear seat was to be occupied. The subsequent release of the airworthiness directive CF-2020-10 mandated the same limitations and meant that occupants of older model Cessna 206 aircraft, particularly those seated in the rear seats, had improved access to the pilot’s forward left cabin door emergency exit. The removal of the middle row seat also improved the visibility and access to both cargo door handles for middle and rear seat occupants. 

The Civil Aviation Safety Authority (CASA) required that the aircraft emergency exits remain unobstructed at all times. Passengers seated in the rear seats of the Cessna 206 with the double cargo door are obstructed by either: 

• the middle row seats, when attempting to access the pilots forward left cabin door
• the flap blocking the forward cargo door when the flaps remain extended.

The majority of aircraft accidents happen during take-off or approach and landing phases of flight. During normal operation, these phases of flight usually require an amount of flap extension, therefore it becomes likely that, in the event of an accident or incident, the flaps would remain extended and hinder the use of the cargo door emergency exit. 

Previous investigations into the Cessna 206 that included fatalities of pilots who had a required knowledge of the use of an emergency exit, have found that the extended flaps blocking the cargo door contributed to the occupant’s inability to exit the aircraft during emergency egress.

The successful ditching of a Cessna 206 in New Zealand in 1999 indicated the increased occupant survivability potential when both emergency exits are clear of any obstruction.

Transport Canada has approved several modifications that provided an exemption to the occupancy limitations set out by the type certificate and airworthiness directive. This allowed the aircraft to maintain its intended 6 passenger configuration. The modifications are commercially available and improve the functionality of the emergency exits and provide access to an alternative or unobstructed emergency exit with the flaps extended.  

The extended flap blocking the forward cargo door has contributed to fatalities in previous accidents. The Cessna 206 ditching and forced landing procedure both prescribe a full-flap landing. However, unless the pilot is able to retract the flaps after the ditching or landing, the flaps would remain extended blocking the forward cargo door.

Transport Canada’s required restriction of the Cessna 206 occupancy, or the approved emergency exit modifications, reduces the risk created by the extended flaps preventing the immediate and unobstructed use of the rear cargo door emergency exit. This significantly improves the occupant’s likelihood of successful egress, during an emergency.

In Australia, CASA has provided warnings regarding the obstruction of the emergency exit and strongly recommended operators to comply with the changes that Transport Canada made. However, the aircraft’s certifying state (United States) has not mandated these changes. 

The ATSB and international transport safety investigations have highlighted the increased difficulty faced by occupants attempting to egress the Cessna 206 when the flaps remain extended. Existing approved emergency exit modifications are available to reduce the risk created by the extended flap preventing the immediate and unobstructed use of the rear cargo emergency exit. 

The approved modifications for the cargo door emergency exit would likely have resulted in occupants of the rear seats successfully opening the forward cargo door and therefore improving the ease of operation of the rear cargo door handle for the occupants or pilot. Alternatively, with a middle row seat removed, rear seat occupants’ path to the forward left cabin door would have been unobstructed.

Other factor that increased risk The aircraft did not have the modifications detailed by CASA for Cessna 206 emergency exits, increasing the likelihood of impeded egress during emergency situations. (Safety Issue)

Safety advisory notice The Australian Transport Safety Bureau strongly encourages operators and owners review Transport Canada Airworthiness DirectiveCF-2020-10, and consider either the removal of a middle row seat to improve rear seat occupants’ access to the pilot’s forward left cabin door or the fitment of approved Cessna 206 emergency exit modifications to reduce the risk created by the extended flap preventing the immediate and unobstructed use of the rear cargo doors during an emergency exit.

Findings

ATSB investigation report findings focus on safety factors (that is, events and conditions that increase risk). Safety factors include ‘contributing factors’ and ‘other factors that increased risk’ (that is, factors that did not meet the definition of a contributing factor for this occurrence but were still considered important to include in the report for the purpose of increasing awareness and enhancing safety). In addition ‘other findings’ may be included to provide important information about topics other than safety factors.  Safety issues are highlighted in bold to emphasise their importance. A safety issue is a safety factor that (a) can reasonably be regarded as having the potential to adversely affect the safety of future operations, and (b) is a characteristic of an organisation or a system, rather than a characteristic of a specific individual, or characteristic of an operating environment at a specific point in time. These findings should not be read as apportioning blame or liability to any particular organisation or individual.

From the evidence available, the following findings are made with respect to the collision with terrain during go‑around involving Cessna U206F, VH-TDQ, 39 km south-east of Moora, Western Australia, on 1 September 2024. 

Contributing factors

• Due to excessive speed on approach for a full flap, short field landing, with a tail wind component, the aircraft landed long and bounced twice.
• The pilot conducted a non-standard approach to the landing area by conducting a base leg join to the easterly runway which had a gradual upslope. This reduced the time available for the pilot to configure the aircraft, reduce airspeed and prepare for a short field landing.
• The pilot mis-selected the flap setting during the attempted go-around. However, the aircraft could not achieve adequate climb performance.

Other factors that increased risk

• The aircraft did not have the modifications recommended by CASA for Cessna 206 emergency exits, increasing the likelihood of impeded egress during emergency situations. (Safety issue)
• The operator’s pre-flight passenger briefing did not include the demonstration of, and pilots were not trained how to operate, the emergency exit via the cargo door with the flaps extended. (Safety issue)
• The pilot was unaware that the rear cargo door on the Cessna 206 could be opened from the outside when the front cargo door was blocked by the extended flaps.
• With the flaps extended in the 10° position when the aircraft came to rest blocking the full opening of the forward cargo door, the rear seat passengers were unable to open the rear cargo door to enable an emergency exit.

Safety issues and actions

Central to the ATSB’s investigation of transport safety matters is the early identification of safety issues. The ATSB expects relevant organisations will address all safety issues an investigation identifies.  Depending on the level of risk of a safety issue, the extent of corrective action taken by the relevant organisation(s), or the desirability of directing a broad safety message to the Aviation industry, the ATSB may issue a formal safety recommendation or safety advisory notice as part of the final report. All of the directly involved parties are invited to provide submissions to this draft report. As part of that process, each organisation is asked to communicate what safety actions, if any, they have carried out or are planning to carry out in relation to each safety issue relevant to their organisation.  Descriptions of each safety issue, and any associated safety recommendations, are detailed below. Click the link to read the full safety issue description, including the issue status and any safety action/s taken. Safety issues and actions are updated on this website when safety issue owners provide further information concerning the implementation of safety action.

The operator’s pre-flight passenger briefing

Safety issue number: AO-2024-049-SI-01

Safety issue description: The operator’s pre-flight passenger briefing did not include the demonstration of, and pilots were not trained how to operate, the emergency exit via the cargo door with the flaps extended.

Safety advisory notice to operators and pilots of Cessna 206

SAN number:

AO-2024-049-SAN-001

The Australian Transport Safety Bureau advises Cessna 206 pilots and operators that due to the difficulties occupants have encountered egressing the rear cargo door as identified in several transport safety investigations, to ensure they are familiar with CASA issued Airworthiness Bulletin 52‑006, and ensure passengers are provided with a thorough safety briefing demonstrating the cargo door emergency egress when the wing flaps remain in the extended position. 

Cessna 206 emergency exit modifications

Safety issue number: AO-2024-049-SI-02

Safety issue description: The aircraft did not have the modifications recommended by CASA for Cessna 206 emergency exits, increasing the likelihood of impeded egress during emergency situations

Safety advisory notice to operators and pilots of Cessna 206

SAN number:

AO-2024-049-SAN-002

The Australian Transport Safety Bureau strongly encourages operators and owners review Transport Canada Airworthiness Directive CF-2020-10, and consider either the removal of a middle row seat to improve rear seat occupants access to the pilots forward left cabin door or the fitment of approved Cessna 206 emergency exit modifications to reduce the risk created by the extended flap preventing the immediate and unobstructed use of the rear cargo doors during an emergency exit.

Safety action not associated with an identified safety issue

Whether or not the ATSB identifies safety issues in the course of an investigation, relevant organisations may proactively initiate safety action in order to reduce their safety risk. The ATSB has been advised of the following proactive safety action in response to this occurrence.

Safety action by Fly Esperance Pty Ltd

Following the occurrence Fly Esperance has made the following amendments to its operations manual: 

• Added CASA pictorial publication ‘non-controlled aerodrome circuit procedures’ to its Circuit and landing procedures and uncontrolled aerodromes section to better clarify the process.
• Added a table to show the recommended aircraft speed and landing weight with the flaps retracted and extended.
• Pilots will now carry portable GPS aircraft tracking devices to improve aircraft tracking when outside ADSB coverage.
• Greater emphasis on training including ICUS training, highlighting what can happen when standard procedures are not followed.   

The changes to the company operations manual are part of a larger amendment that will be under review by CASA in due course.

Glossary

AD	Airworthiness Directive
AFM	Aircraft flight manual
ALA	Aircraft landing area
AMSL	Above mean seal level
ATSB	Australian Transport Safety Bureau
AWB	Airworthiness Bulletin
CAA	Civil Aviation Authority (Australia)
CASA	Civil Aviation Safety Authority
CASR	Civil Aviation Safety Regulations
FAA	Federal Aviation Association
ft	Feet
kt	Knots
MOS	Manual of Standards
NAIPS	National Aeronautical Information Processing System
NM	Nautical miles
SEB	Service Bulletin
STC	Supplemental type certificate
VREF	Landing reference speed

Sources and submissions

Sources of information

The sources of information during the investigation included:

• the pilot of the accident flight
• Fly WA Group
• the chief pilot of Fly WA Group
• Civil Aviation Safety Authority
• passengers of the accident flight
• Textron Aviation
• Bureau of Meterology
• Flight Radar 24
• accident witnesses
• video footage of the accident flight and other photographs and videos taken on the day of the accident
• United States Federal Aviation Administration
• Transport Canada
• Transport Safety Board of Canada

References

Australian Transport Safety Bureau. (2021). Collision with water involving Textron Aviation Inc. (Cessna) 206, VH-AEE, near Happy Valley, Fraser Island, Queensland, on 29 January 2020. Retrieved from /publications/investigation_reports/2020/aair/ao-2020-010#safetysummary0

Canada, T. (2020, April). Airworthiness Driective CF-2020-10. Retrieved from https://wwwapps.tc.gc.ca/Saf-Sec-Sur/2/cawis-swimn/AD_dl.aspx?ad=CF-202…

Canada, T. (2024, June). https://www.bst-tsb.gc.ca/eng/enquetes-investigations/aviation/2024/a24…. Retrieved from https://www.bst-tsb.gc.ca/eng/enquetes-investigations/aviation/2024/a24…

Civil Aviation Safety Authority. (2009). Advisory Circular AC21-30(2). Retrieved from https://www.casa.gov.au/sites/default/files/2021-08/advisory-circular-2…

Civil Aviation Safety Authority. (2017). Manual of Standards. Retrieved from Part 90: https://www.legislation.gov.au/F2010L03095/latest/text

Civil Aviation Safety Authority. (2024). Civil Aviation Safety Regulations. Retrieved from Part 90: https://www.legislation.gov.au/F1998B00220/latest/text/2

Civil Aviation Safety Authority. (2025, January). Advisory Circular AC 91-10 v1.3. Retrieved from Operations in the vicnity of non-controlled aerdromes: https://www.casa.gov.au/operations-vicinity-non-controlled-aerodromes

Civil Aviation Safety Authority. (2025). Airworthiness Bulletin 52-006. Retrieved from https://www.casa.gov.au/sites/default/files/2025-01/awb_52-006_issue_2_…

Civil Aviation Safey Authority. (2011). AIRWORTHINESS DIRECTIVE AD 206/47 amndt 3. Retrieved from https://services.casa.gov.au/airworth/airwd/ADfiles/under/cessna206/CES…

Federal Aviation Administration. (1990). Supplemental Type Ceretificates. Retrieved from SA1470GL: https://drs.faa.gov/browse/STC/doctypeDetails?modalOpened=true

Federal Aviation Administration. (2024). Delegated Organisations. Retrieved from https://www.faa.gov/other_visit/aviation_industry/designees_delegations…

Federal Aviation Administration. (2024, July 29). Federal Aviation Administration Current Regulations. Retrieved from Federal Aviation Administration: https://www.faa.gov/other_visit/aviation_industry/designees_delegations…

Transport Accident Investigation Commission, N. Z. (1999). Accident Investigation 99-001. Retrieved from https://www.taic.org.nz/sites/default/files/inquiry/documents/99-001.pdf

Wikipedia. (n.d.). Cessna. Retrieved from Wikipedia: https://en.wikipedia.org/wiki/Cessna

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
• Fly Esperance chief pilot
• Textron Aviation
• Civil Aviation Safety Authority.

Submissions were received from:

• the pilot of the accident flight
• Fly Esperance chief pilot
• Civil Aviation Safety Authority.

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

Appendices

Appendix 1 – Cessna 206 occurrences

Year	Injuries	Summary	Link	Country of Occurrence
2020	2 Persons on board (pob) 2 minor injuries	During a landing at a beach landing area on Fraser Island, Queensland, the Cessna U206G aircraft veered significantly to the left. Once airborne it was identified that the rudder was jammed in the full‑left position and the pilot had to apply full opposite aileron to maintain control. The engine subsequently stopped, possibly due to fuel starvation and the aircraft collided with water. Unable to open the pilots door the trainee pilot kicked the cargo door to force it open past the extended flap.AO-2020-010	ATSB AO-2020-010	Australia
2018	5 pob 3 fatalities	During a landing on water, a float equipped U206G nosed over. The pilot and one passenger survived. The three remaining passengers, who received no injuries during the accident, were unable to escape the fuselage and drowned. The passengers were found with their seatbelts unfastened but had not opened the cargo door, which was blocked by 20˚ flap.	TSB A180129	Canada
2012	5 pob 1 fatality	During a landing on water, the float equipped 206 nosed over. The flaps were extended blocking the cargo door. The pilot and three passengers escaped by bending the cargo door. The fourth passenger, found in her seat with the seatbelt on, likely died through injuries caused by the accident.	NTSB ANC12FA073	United States
2010	5 pob 4 fatalities	During cruise, the engine failed, and the pilot conducted a ditching into Lake Michigan. The pilot did not lower the flap; however, the cargo door had not been opened. The pilot survived. Two passengers were found outside the aircraft however, their life jackets had failed. Of the two passengers found inside the cabin, one had removed their seatbelt.	NTSB  CEN10FA465	United States
2003	2 pob 1 fatality	During the landing on water, the float equipped 206 flipped over. Contrary to instructions provided by the pilot, the passenger made their way to the rear of the aircraft, was unable to exit, and drowned.	TSB aviation occurrence A03Q0083	Canada
2001	5 pob 1 fatality	During the landing, the aircraft collided with a hole in the runway, nosed over and slid into a river. The pilot and three passengers escaped with minor injuries, however, one of the passengers drowned trying to escape the aircraft.	Aviation Safety Network Wikibase Occurrence 45813	Venezuela
1999	6 pob	During an aerial surveillance air transport flight around Pitt Island, New Zealand the aircraft had a sudden engine failure and ditched in the sea. The pilot and four passengers escaped from the aircraft and swam to shore without the aid of life-jackets. Aircraft flaps were not extended during the ditching.	Transport Accident Investigation Commission, New Zealand 99-001	New Zealand
1997	3 pob 2 fatalities	During the landing on water, the float‑equipped aircraft flipped as the landing gear had not been retracted. Two passengers were unable to exit the aircraft and drowned. The door handle was found in the upright closed position.	TSB Aviation investigation report A97C0090	Canada
1996	6 pob 4 fatalities	During the take-off on water, the aircraft capsized. The pilot and three passengers drowned in the rear of the aircraft, when the pilot could not open the cargo door. Two passengers escaped through the pilot door. There was evidence that an adult had attempted to open the cargo door.	TSB Aviation investigation report A96Q0114	Canada
1989	5 pob 4 fatalities	During the landing on a dam, the float‑equipped 206 nosed over as the landing gear had not been retracted. The pilot and one passenger survived, but three passengers were fatally injured.	Aircraft Accident Investigation Board – Norway 06/99	Norway
1985	5 pob 3 fatalities	During the landing on a dam, the float‑equipped 206 nosed over as the landing gear had not been retracted. The pilot and one passenger survived, but three passengers were fatally injured.	ATSB  198503550	Australia

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.

Investigation summary

What happened

On 13 October 2024, an Extra EA 300-LT aircraft, registered VH‑XKW, with a single pilot on board, departed from Bathurst Airport to conduct a trophy delivery at the annual Bathurst 1000 motor race, at the Mount Panorama circuit, about 10 km west‑south‑west of the airport. After landing on Mountain Straight (the location of the trophy handover), the aircraft collided with a concrete barrier. Following the trophy handover, the aircraft departed overhead spectator stands with a damaged tailplane.

What the ATSB found

The ATSB found that in preparing for the event, the pilot planned to land and take-off over a designated NO FLY AREA occupied by spectators, which did not comply with the Civil Aviation Safety Authority’s (CASA) required spectator safety heights and distances for an air display. The aircraft struck a barrier after landing on Mountain Straight during a reversal turn resulting in damage to the tailplane. However, following advice of the impact from a media helicopter, the pilot did not conduct an external inspection and subsequently departed overhead a spectator NO FLY AREA.

The ATSB also found that the CASA inspector approved the pilot’s application to land and take‑off from Mountain Straight, despite limited information from the applicant and the published safety constraints of the NO FLY AREAs surrounding the planned landing area.

Safety message

The CASA‑published Advisory Circular 91-21 describes the safety requirements for air displays and provides the guidance for completing air display applications. As expressed in AC 91-21, while the level of risk for air display participants may be elevated, the displays must be planned and conducted such that they do not increase the level of risk for spectators and other uninvolved parties.

All air display personnel, such as the organiser, air/ground coordinator(s) and participant(s), should ensure that air displays are not only planned to be in compliance with those requirements, but that they are also conducted in a way that is consistent with the approved arrangements. 

The investigation

Decisions regarding the scope of an investigation are based on many factors, including the level of safety benefit likely to be obtained from an investigation and the associated resources required. For this occurrence, a limited-scope investigation was conducted in order to produce a short investigation report, and allow for greater industry awareness of findings that affect safety and potential learning opportunities.

The occurrence

At 0953 local time on 13 October 2024, an Extra EA 300-LT aircraft, registered VH-XKW, with a single pilot on board, departed from Bathurst Airport to conduct a trophy delivery at the annual Bathurst 1000 car race. Recorded data indicated that after take-off, the aircraft proceeded to a holding area where it arrived at 0956. After completing a left and right orbit, the aircraft left the holding area in the company of a media helicopter filming the trophy delivery event. The aircraft then commenced a left hand circuit to line‑up for a landing in the southerly direction on the Mountain Straight section of the Mount Panorama motor racing circuit, about 10 km west‑south‑west of the airport, where the trophy was to be delivered (Figure 1).

Figure 1: Landing and take-off of incident flight between Bathurst Airport and Mount Panorama

Source: Pilot’s OzRunways data and Google Earth, annotated by the ATSB

At 1003, the aircraft lined up on a 1 NM final approach at an altitude of about 2,900 ft. At this time, Bathurst Airport recorded a wind velocity of 7 kt from 071° True (T) after a peak of 13 kt from 048° T at 0959. The pilot reported there was a crosswind from the left and a small tailwind component on final, but that they were within the aircraft limits and there were no wind gusts. The aircraft arrived overhead the start of Mountain Straight at an altitude of about 2,402 ft (50 ft above ground level) with a groundspeed of 89 kt, after passing overhead spectators on short final, before landing on the grass to the left of the bitumen. The pilot then manoeuvred the aircraft to the right from the grass onto the bitumen as it continued to slow while travelling uphill along the straight.

The racetrack barriers on either side of Mountain Straight narrowed in the southerly direction and the pilot reported that in the narrower section the aircraft would need the additional space of a driveway entrance to turn around.[1] After manoeuvring the aircraft onto the bitumen, the pilot decided to turn the aircraft around before the narrow section and attempted what they described as an ‘aggressive’ turn, which was a right turn followed by a left reversal turn.

Footage and recorded data of the landing indicated that the left wheel moved off the left edge of the bitumen at a groundspeed of about 27 kt just before the aircraft veered right and traversed the bitumen track from left to right. The aircraft slowed to about 13 kt groundspeed when the right wheel exited the bitumen onto the grass on the right side of the track. The aircraft then spun around about 90° to the left before the right rear corner of the tailplane impacted the concrete track barrier and stopped the aircraft. At the time, the aircraft was about 530 m along the straight from the 50 ft threshold height. Engine power then increased, and the aircraft moved away from the barricade, completed the left reversal turn and taxied down the straight, in the opposite direction to the landing, to the location of the trophy delivery, with damage to the right rear corner of the tailplane (Figure 2).

Figure 2: Tailplane damage after collision

Source: YouTube, modified and annotated by the ATSB

The camera operator in the media helicopter saw the aircraft’s tail impact the barrier during the turn and immediately reported this to the media helicopter pilot. The media helicopter pilot in turn immediately informed the incident pilot of the collision over the radio and recommended the pilot check the aircraft’s tail before take-off. The pilot contacted their team member at the track via radio, but reported at interview that the team member could not observe the collision. The pilot also reported that they did not feel the contact with the barrier, and that after the trophy was delivered, a full control check was conducted on the ground as well as a visual check of the tail from their cockpit seated position, with no control problems or visible damage identified.

The pilot then taxied the aircraft back uphill along Mountain Straight, turned around to line‑up in the northerly direction (opposite to the landing direction), and departed overhead the spectators to return to Bathurst Airport. After arrival at the airport, the pilot saw the damage to the tailplane and contacted the Civil Aviation Safety Authority (CASA) in response to a request for information about the incident.

Context

Pilot information

The pilot held a recreational pilot licence (aeroplane), issued by CASA in January 2019, with the required ratings and endorsements to operate the Extra EA 300‑LT and a current class 2 aviation medical certificate. The pilot’s last flight review in May 2023 included an activity endorsement to conduct aerobatics to a lower limit of 500 ft above ground level. The pilot reported that they had accumulated about 800 hours of flying experience, which included 320 hours operating the Extra. The pilot provided a fatigue self-assessment score of ‘1 – fully alert’ for the time of the accident. 

Meteorological information

The 1000 METAR[2] for Bathurst Airport, which has an elevation of 2,435 ft, provided a wind velocity of 10 kt from 050° T, visibility greater than 10 km, cloud base broken at 2,900 ft above the airport elevation, temperature of 15°C and QNH[3] of 1026 hPa. This resulted in a pressure altitude of 2,001 ft and density altitude of 2,476 ft for the start of Mountain Straight. The 1‑minute wind data recordings for the period 0945–1015 indicated the wind direction varied from 016°–077° T, and the speed varied from 7–13 kt. At the time of the aircraft’s final approach and landing between 1003 and 1004, the recorded wind velocities at Bathurst Airport were 071° at 7 kt (1003) and 050° at 7 kt (1004).

Mountain Straight

Mountain Straight is oriented 190° T / 010° T and is about 1,111 m in length from the northern end at Hell Corner, just after Pit Straight, to the first turn at Griffins Bend.[4] It climbs in a southerly direction towards Griffins Bend, with an average gradient of about 5.4% (Figure 3). The northern (lower) half of the straight is about 20 m wide between the western edge of the bitumen track and the barriers on the eastern side of the track. The width reduces to about 8–10 m for the southern (upper) half of the straight, starting about 585 m from the northern end, where there is trackside tree coverage and co-located infrastructure leading to Griffins Bend.

Figure 3: View of Mountain Straight looking to the south with VH-XKW on approach

Source: YouTube, annotated by the ATSB

Aircraft information

General information

The Extra Flugzeugproduktions – und Vertriebs EA 300-LT aircraft was a tandem, 2-seat aerobatic monoplane with the rear seat instrumented for the pilot. It was built with a steel-tube construction and composite material for the wings, empennage and landing gear, designed for unlimited acrobatics up to +/-10 G and was operated under a special certificate of airworthiness in the experimental category. 

Performance information

The pilot operating handbook indicated that the aircraft’s final approach speed in the lower weight category of 820 kg (single-pilot using centre fuel tank) was 79 kt indicated airspeed. The calculated landing distance over a 50 ft obstacle at 79 kt on a concrete runway with maximum braking was 591 m at 2,000 ft pressure altitude and a temperature of 15°C, with a 193 m landing roll. The landing roll increased by 15% on dry grass due to the reduced braking efficiency, which increased the landing distance to 620 m.

The performance tables did not provide a correction factor for an upslope landing or a tailwind and therefore, the actual landing distance required on the day could not be determined. The performance tables also did not provide a correction factor for a downslope landing. However, an increase of 5% to the landing distance for each 1% of the average slope (5.4%) would result in a downslope landing distance of 751 m with maximum braking on bitumen.[5]

Practice day

The pilot was provided a practice opportunity for the air display on 10 October, which included a practice landing and take-off from Mountain Straight. The pilot conducted the practice landing onto the bitumen, which required an approach over a tree on the western side of the track, near the northern end of the straight, and a rollout along the upper narrow section of track to a driveway for the turnaround. On 12 October, the pilot re-inspected Mountain Straight on the ground and decided to modify the approach and touchdown to land on the grass on the eastern side of the bitumen to be closer to the northern end of the straight and the location of the trophy handover.

Air display applications and approvals

Applications

Prior to conducting an air display, the organiser, who can be the pilot conducting the display, must apply to CASA with supporting attachments (CASR form 91.180) for approval to conduct the display. To assist in the preparation of the supporting attachments, CASA published advisory circular AC 91-21 Air displays in November 2022 and the circular was referenced in CASR form 91.180 wherever an attachment was required. Several sections of AC 91-21 were relevant to the pilot’s application for Bathurst including:

3.4 Events that organisers are planning for the first time

3.4.4 For an air display approval, CASA's test of safety is that the display will result in the preservation of a level of aviation safety that is at least acceptable given the circumstances. CASA acknowledges that the level of risk for some air displays, for the persons onboard the aircraft, is elevated compared to more routine private operations. However, air displays are to be planned to not increase the level of risk for uninvolved parties, such as spectators, compared to routine private operations.

5.3 Display Coordinator

5.3.1 The display coordinator is appointed by, and responsible to, the display organiser. The display coordinator controls the actual flying program and assumes overall responsibility for the airborne component and safety of the display event.

5.3.2 The documentation submitted to CASA for an air display approval must include the details of the display coordinator.

5.6 Ground Control Coordinator

5.6.1 The ground control coordinator is an essential component of a fly-in, competition or air display. The ground control coordinator should have a considerable and verifiable aviation background, commensurate with the planned event, that enables them to identify aviation ground-based hazards and their impact on persons and property during the event and are responsible to the Display Organiser.

9.3 Manoeuvring limitations

9.3.1 Aircraft used in an air display are subject to the following manoeuvring limitations:

• except where specifically requested as part of the program of events and then part of the approval, an aircraft in flight below 1 500 ft AGL must not:

     ◦ track or manoeuvre towards spectators within a horizontal distance of 500 m; or

     ◦ pass within 200 m horizontal distance from spectators. 

9.7 Weather minima

9.7.1 Minimum weather conditions must be determined by the display organiser in advance of the air display, published in the display instructions and strictly observed. This makes the decision to cancel the display in the event of bad weather less subjective and minimises pressure on the display organiser to proceed with the display in less than favourable conditions.

Approvals

The CASA air display application form CASR 91.180 (with any applicable attachments) was to be submitted to CASA Regulatory Services, who allocated assessment of the application to a CASA team in the region where the air display was planned to occur. The task was then allocated to a Flight Operations Inspector (FOI) who had completed the CASA training course for air displays. The FOI was required to assess the application guided by a CASA worksheet (OPS.25) and to communicate with the applicant to seek more information if required or to challenge the application’s compliance with the requirements of AC 91-21. The FOI was required to record the answers to the worksheet’s questions as well as their assessment decision with their reasoning. If the FOI recommended approval of the air display application, CASA subsequently sent the applicant their instrument to conduct the air display.

Pilot’s air display applications

Prior to the Bathurst event, the pilot submitted 2 air display applications in 2024 for motor racing events, with a planned landing and take-off on the racetrack for events in Perth in May (Barbagallo racetrack) and Melbourne in September (Sandown racetrack).

Perth SuperSprint – May 2024

The initial application for the Perth event was submitted by a third party on behalf of the pilot and included a landing on the Barbagallo racetrack back straight on 17 May followed by a take-off from the main (front) straight on 18 May. The application’s appended risk assessment included the landing and take-off area dimensions and a crosswind limit of 12 kt for the landing and was otherwise consistent with the sample risk assessment in appendix C of AC 91-21. However, it did not address the AC 91-21 manoeuvring limitation safety distances for spectators for the proposed landing and take-off. The risk assessment included the presence of an ‘air-boss’ who could call STOP DISPLAY, a ground observer who could call STOP DISPLAY and a display coach who would provide ‘go / no-go authority’. The initial display diagram in the application did not identify the landing and take-off areas. 

When the initial application was received, CASA assigned the assessment task to an FOI who contacted the pilot via email on 5 April, to introduce themselves and provide a list of questions and items that needed rectification. The following requests for clarification from the first review were of relevance to the Bathurst incident:

• If the pilot is the organiser and will be flying, who will be handed control of the event when the pilot is in the air?
• For the landing and take-off, CASA needed to see the area in person to ensure conformance with reg 91.410 of CASR 1998, AMC/GM 91.410 and AC 91-02 Guidelines for aeroplanes with MTOW not exceeding 5700kg – suitable places to take-off and land.
• The Display Lines and AXIS diagrams needed to clearly show the requirements of section 9.3 [Manoeuvring limitations] and 9.4 [Display lines] of AC 91-21 Air Displays.
• The identities of the personnel linked to the display, including the air boss, were required on the application.

The documents were resubmitted, and after a second review, CASA sent the pilot another email on 16 April. This reiterated a number of their initial concerns plus additional items that needed to be addressed, which included prohibiting use of the front straight for take-off and confirmation that the aircraft would not be manoeuvred towards spectators in accordance with the limits in AC 91‑21.

On 8 May, the FOI sent another email to the pilot after completing a third review of the submission and suggested a telecommunications meeting to help resolve the outstanding matters. The subsequent revisions to the display diagram identified the relevant straights for the planned landing, taxi and take-off along with the spectator areas and display box. Two CASA inspectors then attended the racetrack on 10 May to inspect the suitability of the back straight for a landing and take-off. The display application was subsequently approved on 13 May. Throughout their correspondence, the FOI repeatedly requested the pilot address the spectator safety distances in AC 91-21 in their application.

The completed OPS.25 worksheet included several restrictions that had been imposed as part of the application review process, including restricting the landing and take-off to the back straight. In their reason for recommendation, the FOI noted that the assessment took longer than usual but was treated as educational as they expected an increase in display applications from the pilot in the future.

Sandown 500 Supercars Championship – September 2024

On 21 August, the pilot applied to CASA Regulatory Services for an air display approval for the Sandown event in Melbourne. The application included a display summary attachment which indicated a proposed landing and take-off from the Sandown track main straight on 15 September for a trophy handover and noted that there would be an experienced aerobatics pilot at the track acting as the display coordinator for the event. However, the display diagram did not identify the approach and departure or spectator NO FLY AREAs. The only recorded risk in the application associated with the trophy handover was ‘Landing with people on track’ and there was no information about the suitability of the main straight for landing and take-off despite this being a source of concern for CASA during the application process for the Perth event.

On 3 September, the CASA FOI who was assigned the task sent the pilot their first round of feedback to the application. The first item listed was that CASA would not issue a display approval while it included a landing and take-off from the main straight as it did not meet the manoeuvring limitations for operations towards, and parallel to, spectators. They also highlighted the need for the display axis in the display diagram to provide adequate safety margins from spectators and populous areas.

On 4 September, the track landing was removed from the display summary and resubmitted to CASA. On 5 September, the FOI requested a copy of the pilot’s updated display diagram, to which the pilot responded with a proposed display axis that crossed the main straight and spectator stands. The FOI then sent the pilot a Google Earth image with a 500 m arc depicting the area where the pilot could not fly towards the spectator stands and a 200 m line depicting the minimum distance the display axis needed to be from the spectator stands in accordance with AC 91-21. The pilot then submitted an updated display diagram that complied with the requirements. CASA issued the pilot with the instrument to conduct the air display on 9 September.

The OPS.25 worksheet included the restriction that there was to be no landing and take-off operations at the Sandown track. Within their reason for recommending approval, the FOI reported that the plan to land on the main straight was ‘rejected as not meeting air display regulatory requirements’, that the display axis was changed to meet the ‘air display requirements in relation to spectators’ and that ‘the applicant was receptive and cooperative during the lengthy assessment process.’

Bathurst 1000 – October 2024

On 30 August, the pilot submitted an air display application for the 2024 Bathurst 1000 motor racing event. The application named the same display coordinator as for the Sandown air display event and included a landing and take-off from Mountain Straight on 13 October and aerobatic displays on 11 and 12 October. The display coordinator was also identified as the ‘ground-boss’ for the display and was:

• responsible for clearing the pilot for the landing and take-off from the track
• responsible for monitoring other traffic during the aerobatics displays
• a member of the emergency response plan and had STOP DISPLAY responsibilities within the risk assessment.

Despite being assigned these responsibilities, the nominated display coordinator reported to the ATSB that, while they agreed to support the Sandown event, they were not at the Bathurst event and were unaware they had been nominated by the pilot on the Bathurst display application submitted to CASA.

The display diagram in the application included the pilot’s aerobatic display axis and the spectator NO FLY AREAs, located inside and outside of the track (Figure 4). The northern end of Mountain Straight was surrounded by NO FLY AREAs but the display diagram did not include the planned approach and departure paths over those areas. Similar to the Sandown risk assessment, the only risk associated with the trophy handover was ‘Landing with people on track’.

There was no information about the dimensions and suitability of the proposed landing area, spectator safety distances or weather limits. The pilot advised the ATSB that the race organisers had a spare trophy at the track if the landing had to be aborted and an off‑track parking location if the aircraft became unserviceable after landing. These measures were in place to mitigate the pressure to land and take-off in unfavourable circumstances but were not included in the risk assessment.

Figure 4: Pilot’s display diagram

Source: Civil Aviation Safety Authority, annotated by the ATSB

On 5 September, CASA acknowledged receipt of the pilot’s application by email, and provided the pilot with the contact details of the FOI assigned to assess the request. The FOI reported to the ATSB that on review of the application, they assumed the pilot would comply with the NO FLY AREAs on the display diagram and that they were unaware of the topography of Mountain Straight.

The FOI did not review any of the pilot’s previous applications and therefore was not aware of the requests to conduct landings and take-offs at the Barbagallo and Sandown racetracks. On 6 September, the FOI issued the display approval without any requests for information or clarification from the pilot and without completing the required OPS.25 worksheet.

Safety analysis

The pilot submitted an air display application with a proposed landing and take-off from Mountain Straight for a trophy handover and a display diagram with NO FLY AREAs annotated surrounding the northern end of Mountain Straight. The pilot marked the display diagram with their proposed aerobatic display axis and submitted this to CASA, which indicated the pilot was aware of the NO FLY AREAs surrounding the track. However, they did not include their approach and departure flightpaths on their display diagram or display summary. The pilot subsequently reported at interview that it was their plan to land uphill and take-off downhill. This needed to be conducted at the northern end of Mountain Straight due to the obstructions alongside the southern end. However, this plan breached the spectator safety distances in AC 91-21, which CASA had brought to the pilot’s attention during interactions as part of their previous track landing applications.

After a practice flight and landing, the pilot moved the touchdown point from the bitumen to the grass, in order to shorten the backtrack for the trophy handover. However, on the day, there was a tailwind component for the landing, which resulted in the aircraft approaching the narrower upper‑half section of track before the pilot was able to reduce the groundspeed sufficiently to control their reversal turn. This contributed to the tailplane impacting the concrete barrier during the turn. While crosswind and tailwind were reportedly within the allowable aircraft limits, the pilot acknowledged the approach should not have been conducted with a tailwind component. The absence of any weather limits for the landing in the display application, or provided by the pilot at interview, indicated the decision to conduct the approach with a tailwind was likely the result of inadequate planning.

The landing and impact with the barrier were captured live by a media helicopter crew, who immediately reported the collision to the incident pilot with a recommendation to inspect the tailplane before take-off. However, the pilot elected not to shutdown the aircraft and exit for an external inspection, or request their team member conduct an inspection, and instead departed overhead the crowd with a damaged tailplane. The pilot had nominated an experienced aerobatic pilot as the display coordinator with authority to stop the display. However, this person was not at the event and was not aware they had been nominated. Therefore, they were unable to challenge the planning or exercise their authority to stop the display after the media helicopter pilot alerted the incident pilot to the collision over the radio.

Air displays are subject to CASA approval, which can include conditions on the display, and in the past CASA had modified or rejected the pilot’s applications to land on a track. This included the Perth SuperSprint event, where the pilot was prohibited from taking off from the front straight, and the Sandown Supercars event where the pilot was prohibited from conducting a track landing due to the elevated risk to those on the ground and co-located infrastructure on the main straight.

The pilot’s Bathurst display application did not include how the landing and take-off would be conducted without breaching the NO FLY AREAs. While the FOI was reportedly unaware of the topography of Mountain Straight, they assumed the pilot would comply with the NO FLY AREAs and that the nominated display coordinator would be in attendance. Consequently, the FOI did not question the pilot’s planning or check the topography, either one of which would have revealed that the spectator safety distance could not be met while landing on the proposed section of the racetrack. In addition, a check of the pilot’s previous air display applications would have revealed they had a history of difficulty applying the requirements of AC 91-21 to their display planning.

Findings

ATSB investigation report findings focus on safety factors (that is, events and conditions that increase risk). Safety factors include ‘contributing factors’ and ‘other factors that increased risk’ (that is, factors that did not meet the definition of a contributing factor for this occurrence but were still considered important to include in the report for the purpose of increasing awareness and enhancing safety). In addition, ‘other findings’ may be included to provide important information about topics other than safety factors.  These findings should not be read as apportioning blame or liability to any particular organisation or individual.

From the evidence available, the following findings are made with respect to the collision with terrain involving Extra EA 300-LT, VH-XKW, about 10 km west-south-west of Bathurst Airport, New South Wales on 13 October 2024. 

Contributing factors

• The pilot planned to land and take-off over a NO FLY AREA occupied by spectators, which breached the required air display spectator safety heights and distances.
• The aircraft struck a barrier during a reversal turn after landing on Mountain Straight, resulting in damage to the tailplane. Following advice of the impact, the pilot did not conduct an external inspection and subsequently departed overhead a spectator NO FLY AREA.
• The Civil Aviation Safety Authority’s inspector approved the pilot’s application to land and take‑off from Mountain Straight despite limited information from the applicant and the constraints of the NO FLY AREAs surrounding Mountain Straight.

Sources and submissions

Sources of information

The sources of information during the investigation included:

• Bathurst Regional Council website
• Civil Aviation Safety Authority
• European Union Aviation Safety Agency website
• Google Earth
• OzRunways recorded data from incident pilot
• the involved pilot
• the pilot of the media helicopter
• the nominated display coordinator
• witness video footage and reports
• YouTube.

References

Civil Aviation Safety Authority (2024) Air displays (Advisory Circular 91-21, v2.2), October 2024, Canberra.

European Union Aviation Safety Agency (2023) Easy access rules for air operations (IR & AMC/GM & CS/GM), retrieved from Easy Access Rules for Air Operations - Revision 21, September 2023 | EASA

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 involved pilot
• Civil Aviation Safety Authority.

A submission was received from:

• Civil Aviation Safety Authority.

The submission was 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.

Investigation summary

What happened

On the afternoon of 11 September 2024, the pilot of a Kawasaki 47GB3‑KH4, registered VH‑BEU and operated by Katherine Helicopters, was conducting a scenic flight over Nitmiluk (Katherine) Gorge, Northern Territory with 2 passengers on board. 

About 13 minutes into the flight, while entering the mouth of the gorge, the pilot reported experiencing an engine power loss and lack of response from the engine. Due to inhospitable terrain in the area, the pilot identified a clear landing spot some distance away and attempted a forced landing at that location, during which time the aircraft collided with terrain.

The pilot and both passengers were uninjured in the incident, however, the aircraft was substantially damaged.

What the ATSB found

Several possibilities were considered during the investigation in relation to the reported engine power loss. While the ATSB did not conduct a physical inspection of the engine in this instance, a post‑incident inspection revealed that a large crack had developed in the engine exhaust pipework. Being a turbocharged engine, the escape of exhaust gases through the crack during operation has likely resulted in an engine power loss during flight due to the loss of boost pressure.

The ATSB also identified that the pilot was unable to cushion the landing during termination of the autorotation, likely due to low main rotor RPM, resulting in the helicopter colliding with terrain.

Safety message

Helicopter operations over harsh terrain offer limited safe emergency landing options. Autorotation to a suitable area in such circumstances requires accurate helicopter positioning and energy maintenance (airspeed and rotor RPM). This makes thorough and regular training in emergency procedures crucial for pilots operating in these demanding environments. The prompt action taken by the pilot, in identifying a suitable landing site, was instrumental in ensuring the safety of all personnel on board.

The investigation

Decisions regarding the scope of an investigation are based on many factors, including the level of safety benefit likely to be obtained from an investigation and the associated resources required. For this occurrence, a limited-scope investigation was conducted in order to produce a short investigation report, and allow for greater industry awareness of findings that affect safety and potential learning opportunities.

The occurrence

On 11 September 2024, the pilot of a Kawasaki Heavy Industries 47GB3‑KH4, registered VH‑BEU and operated by Katherine Helicopters, was conducting scenic flights over Nitmiluk (Katherine) Gorge, Northern Territory.

During the morning, the pilot conducted the required daily checks on the helicopter and completed a passenger flight over the gorge (Figure 1). After returning to base, the pilot refuelled the helicopter and completed short, uneventful ferry flights to Katherine Museum and return.

Figure 1: Nitmiluk (Katherine) Gorge scenic flight overview 

Source: Google Earth, annotated by the ATSB

That afternoon, the pilot met 2 passengers at the operator’s base, and then completed the flight manifest including the passengers’ weight details, based on verbal information provided by the passengers. The pilot carried out their pre-departure checks, including a flat‑pitch check,[1] which were all normal. A safety briefing was also undertaken with both passengers, which reportedly included:

• use of seatbelts
• in‑flight procedures
• operation of the doors and emergency exits
• actions to be taken in case of an emergency.

At around 1451 local time, the helicopter departed and after making a turn towards the north, the pilot gradually climbed to about 1,000 ft above mean sea level (AMSL), proceeding north‑easterly along the Katherine River in the direction of the gorge.

About 10 minutes later, the pilot climbed further to a height of about 1,400‍–‍1,500 ft AMSL to fly neighbourly[2] while approaching the escarpment bordering Nitmiluk National Park (Figure 2). The pilot then arranged separation with the pilot of a second helicopter in the area, using the common traffic advisory frequency (CTAF).

Figure 2: View from helicopter of Nitmiluk National Park

Source: Passenger photograph, annotated by the ATSB

Approximately 3 minutes later, as the helicopter was entering the mouth of the gorge, the pilot noticed that the engine did not respond when they increased the throttle, and that the helicopter was decelerating and losing height. Due to being overhead undulating rocky terrain, the pilot commenced a right turn in search of a suitable landing site, in case they had to conduct a landing (Figure 3).

The pilot reported that the ensuing events occurred extremely quickly. While turning around, the helicopter kept slowing and the engine did not respond to throttle movements. They noticed a significant change in the engine noise, described as a low‑pitched ‘whir’ sound, and reported feeling stiffness in the pedals. Not knowing what was wrong with the engine, the pilot lowered the collective[3] and entered autorotation (see the section titled Autorotation). 

During the descent, the pilot glanced at the instruments and noted that the engine RPM needle was split[4] from the main rotor RPM needle and again tried unsuccessfully to increase the throttle. The pilot later advised that the main rotor RPM was well below the green arc on the gauge, and the engine RPM was just below idle. The pilot reported identifying a landing site in a clearing about 400‍–‍500 m to the west of their location and broadcast a MAYDAY[5] call on the CTAF. 

The helicopter proceeded downwind towards the clearing, attaining a maximum groundspeed in excess of 83 kt. Given the prevailing wind, that equated to an airspeed of about 70 kt, which was higher than the recommended autorotation speed for the helicopter type (see the section titled Autorotation). However, during the final approach to the selected landing site, the groundspeed, and given the crosswind approach, also airspeed was reduced to about 50 kt.

Figure 3: Helicopter flight path with identified elevation and ground speed

Source: OzRunways data on Google Earth, annotated by the ATSB 

The passengers reported that during the descent, communication from the pilot was minimal. They were not advised by the pilot to brace for impact; however, upon hearing the MAYDAY call and seeing the pilot attempt an unexpected landing, both passengers suspected that an emergency situation had developed, and chose not to interrupt the pilot or distract them from their actions.

The pilot reported that, on nearing the landing site, they attempted to flare the helicopter but there was minimal flare effect, which they assessed was most likely due to low main rotor RPM. Consequently, the pilot attempted a run‑on landing, during which the helicopter collided with terrain, damaging its tail rotor/shaft and skids (Figure 4).

Figure 4: Helicopter accident site

Source: Operator 

After landing, the pilot shut off the fuel, magnetos and battery. After checking on the passengers, the pilot disembarked the aircraft, ensured it was safe to exit with the main rotor blades still rotating, and then instructed the passengers to evacuate the aircraft. The pilot of the other helicopter operating in the area repeated the MAYDAY call on the area frequency and then circled overhead the accident site. A rescue crew arrived onsite shortly after and the pilot and both passengers were evacuated uninjured.

Context

Pilot information

The pilot held a commercial pilot licence (helicopter) and a class 1 aviation medical certificate. At the time of the incident, they had accumulated about 380 hours total aeronautical experience. All the pilot’s training and most of their flying experience has been obtained operating Robinson R44 helicopters. They had been flying for Katherine Helicopters for about 3 months. 

While at Katherine Helicopters, the pilot received their Bell 47 endorsement after undergoing about 3 hours of training with an instructor that included the conduct of emergency procedures. The pilot also performed about 10 hours of in command under supervision (ICUS)[6] training with the operator.

Operator information

The operator was a helicopter tour operator based in Katherine, Northern Territory. It operated 2 Bell/Kawasaki 47 Helicopters and offered tour flights throughout northern Australia. 

Previous incidents 

The pilot had been involved in another engine failure incident on a second helicopter of the same type with the operator in July 2024, wherein an engine cylinder failed. The pilot completed a successful autorotation and there were no reported injuries. While this matter was reported to the ATSB, it was not investigated.

In addition to the incident above, the other helicopter operated by the operator was involved in a third off field landing, arising from an engine fault, in February 2024. 

Helicopter information     

The helicopter was a Kawasaki Heavy Industries 47G3B‑KH4, manufactured in 1969 in Japan by Kawasaki Heavy Industries and first registered in Australia on 20 June 1996. At the time of the accident, VH‑BEU had about 7,495 hours total time in service and had flown about 40 hours since its last periodic service inspection. 

Engine and turbocharger system

VH‑BEU was powered by a Textron Lycoming TVO‑435, 6‑cylinder, vertical direct drive, horizontally opposed, turbocharged engine. The turbocharger increases the density of the carburettor inlet air to maintain the available power as altitude increases. 

During operation, the exhaust gases expelled from the 3 cylinders on either side of the engine are merged into a single pipe, through which the gases are diverted either to the turbocharger or to the exhaust bypass valve (waste gate), or both (Figure 5).

As the engine power is increased, oil pressure builds up in the exhaust bypass valve assembly and the waste gate in the exhaust system is closed. This diverts the exhaust gas to the turbocharger turbine wheel, compressing the intake air and increasing the available engine power output.

Figure 5: Schematic diagram of engine and turbocharger operation

Source: Lycoming Operator’s Manual, annotated by the ATSB

Maintenance history

As part of the investigation, the ATSB requested the maintenance logs and component log cards for the aircraft. Although the provided information was incomplete, the maintenance history was able to be inferred from the supplied documents as follows:

• Lycoming engine TVO‑435, S/N: L‑751‑52 was installed February 2000 at 6,752 airframe hours. The engine component control card showed a number of zero‑hour components at the time of engine installation, indicating that this engine was likely either a new or overhauled unit. Lycoming Service Instruction No. 1009BE specified a 12‑year, 1,000 hour time between overhauls (TBO). This interval was correctly annotated in the engine log card.
• The engine was removed on 24 February 2014 (+14 years) at 7,088 airframe hours (+336 engine hours), and was bulk stripped in lieu of being overhauled, to satisfy the requirements of CASA air worthiness bulletin (AWB) 85‑5 Issue 1.[7] The same engine was refitted on 20 March 2014.

The information supplied to the ATSB showed that prior to November 2022, the aircraft flew only limited hours, having recorded 425 airframe hours in 22 years (at an average of 19.3 hours/year). Depending on how these hours were flown, the aircraft may have required special maintenance actions and/or storage procedures. If these actions were not taken, corrosion, or contamination of components may affect serviceability. No record of storage or preservation penalty maintenance was identified in the provided records. 

Autorotation

When an engine failure occurs in a single‑engine helicopter such as the Kawasaki 47GB3‑KH4, the pilot must immediately lower the collective and enter autorotation to reduce rotor drag sufficiently to maintain normal rotor RPM. This is a power‑off manoeuvre wherein the engine is disengaged from the main rotor and the rotor blades are driven solely by the upward flow of air through the rotor during descent. The most common reasons for an autorotation are an engine or drive system failure. If the engine fails, the freewheeling unit[8] automatically disengages the engine from the main rotor, allowing it to rotate freely. The tail rotor, still driven by the main rotor transmission, continues to provide yaw control via the anti‑torque pedals.

The United States Federal Aviation Administration Helicopter Flying Handbook noted that the rate of descent during autorotation is influenced by various factors, including:

• bank angle
• density altitude
• gross weight
• main rotor RPM
• trim condition
• airspeed.

Pilots control the autorotative descent rate using airspeed and main rotor RPM. Airspeed is managed with the cyclic[9] pitch control, similar to normal powered flight. The descent angle can range from vertical to a minimum angle for maximum horizontal range. The rate of descent is highest at zero airspeed, reaches its minimum at approximately 50‍–‍60 kts (depending on the helicopter and conditions), and increases again at higher speeds.

During an autorotative landing, the kinetic energy associated with the helicopter’s airspeed and rotating main rotor blades are used to arrest the descent and cushion the landing. Termination of the autorotation usually involves initially flaring the helicopter to reduce the airspeed, rate of descent and, if necessary, increase the rotor RPM. The degree of flare effect is influenced by both the airspeed at the time aft cyclic is applied, as well as the rate of cyclic application.

Autorotative terminations at very low airspeeds are more challenging than those performed at the minimum rate of descent airspeed as they offer minimal flare effect. In that case, cushioning the landing using the stored rotor energy requires more precise collective application.

The Kawasaki 47G3B-KH4 flight manual stated that, in the case of an engine failure, the pilot must:  

execute a normal autorotative descent and establish a level attitude prior to ground contact. At a height of approximately 10 feet above the ground, apply collective pitch in sufficient quantity to stop descent as ground contact is made. The best descent speed is 55 mph [48 kt].

Meteorological information

At the time of incident, visibility was in excess of 10 km, with scattered cloud[10] well above the aircraft operating height, no precipitation and an east‑south‑easterly wind at 11 kt.

The meteorological conditions reported by the pilot at the time of incident were consistent with the Bureau of Meteorology observations, which recorded a temperature of 36°C and dew point[11] of 11°C at the incident location. 

The process of vaporising fuel in a carburetted engine can cool the airflow sufficiently to permit ice formation in the carburettor throat that restricts airflow to the engine. According to the Civil Aviation Safety Authority Carburettor icing probability chart, the probability of carburettor icing, based on the prevalent temperature and dewpoint at Katherine Gorge was on the outer limit of the ‘light icing – cruise or descent power’ zone. Of note however, the turbocharger compressor used in the Kawasaki 47G3B‑KH4 heats the inlet air to the carburettor, significantly reducing the potential for carburettor icing. 

Operating weight

The passenger manifest completed by the pilot prior to take‑off recorded the empty weight of the aircraft, the pilot and both passengers, plus fuel. An allowance of 100 kg was made for the weight of fuel. The passenger weights were only verbally requested, and not physically checked by the pilot. However, the calculated total take‑off weight was well below the maximum take‑off weight so any inaccuracy in passenger weights was unlikely to have resulted in the aircraft being overloaded. 

Aircraft fuel 

The operator conducted an examination of the fuel in the aircraft following the incident and reported to the ATSB that there was adequate fuel remaining in the tank. 

The operator also stated that the aircraft had been refuelled with premium 130 octane fuel by the pilot prior to take‑off, and that a post‑incident examination of the fuel quality did not reveal any signs of contamination or leakage.

Engine examination

Following the incident, the operator started the Lycoming TVO‑435 engine and observed that the wastegate did not operate. Thereafter, they removed the engine and delivered it to a third‍ party maintenance facility for examination. As depicted in Figure 6, the post‑incident inspection of the engine revealed the presence of an approximately 6.5 cm crack on the right exhaust collector, with no other defects identified. 

The exhaust system of the aircraft engine attains extremely high operating temperatures. The consequent widening of the crack due to heat expansion would result in the escape of exhaust gases from the defective section, resulting in inadequate drive pressure for the turbocharger compressor and reduced power output. Information provided by the engine manufacturer supported that conclusion. As such, exhaust gas bleed from the crack before the turbocharger resulted in the wastegate remaining closed. 

The ATSB did not undertake a metallurgical analysis of the exhaust pipe, however, exhaust systems are generally prone to metal fatigue over time due to continuous vibration under corrosive conditions and a cyclical pattern of constant heating and cooling with extreme thermal fluctuations.[12]

While it could not be established when the exhaust crack occurred, the maintenance facility that conducted the post‑accident engine examination assessed that, based on the location and appearance of the defect, it was likely not impact‑related. They further stated that, as the helicopter did not have an engine cowl, the leaking exhaust gases would not have left a residue. This would have made the crack more difficult to detect during a pre‑flight inspection when the engine was cold.

Figure 6: Cracked exhaust collector pipe

Source: the maintenance facility that conducted the engine strip down inspection, annotated by the ATSB

Safety analysis

Engine power reduction

The sequence of events described by the pilot and passengers were consistent with a loss of aircraft engine power during flight, necessitating an emergency landing. The ATSB considered the following potential reasons for the reduction in engine power:

• weather conditions, including carburettor icing
• fuel contamination or starvation
• handling‑related issues
• engine and/or associated systems defect. 

The evidence gathered by the ATSB during the investigation indicated that the 3 initial possibilities were unlikely. 

However, based on information from the engine manufacturer and the personnel that conducted the post‑accident engine examination, a pre‑existing crack in the exhaust collector likely reduced the engine power output during the flight. 

Helicopter maintenance

The ATSB identified that low utilisation of the helicopter may have required special maintenance actions and/or storage procedures to be undertaken to prevent component corrosion or contamination. While there was no evidence that such maintenance was undertaken, it was not possible to determine whether its absence contributed to the crack in the exhaust system. 

Autorotation

Analysis of flight data identified that the helicopter was over inhospitable terrain at the time of the power loss. After turning towards a suitable landing site, the pilot commenced an autorotation to that location. The helicopter proceeded downwind, initially attaining a maximum airspeed of about 70 kt. The airspeed was then reduced to close to the target minimum rate of descent airspeed of 48 kt, providing good potential flare effect to both slow the helicopter prior to touchdown and increase the rotor RPM if necessary.

Despite that, the pilot reported there was minimal flare effect when they approached the landing site, likely due to low rotor RPM. As a result, the pilot was unable to prevent the helicopter colliding with terrain during the termination. Importantly however, none of the occupants were injured.

Findings

ATSB investigation report findings focus on safety factors (that is, events and conditions that increase risk). Safety factors include ‘contributing factors’ and ‘other factors that increased risk’ (that is, factors that did not meet the definition of a contributing factor for this occurrence but were still considered important to include in the report for the purpose of increasing awareness and enhancing safety). In addition ‘other findings’ may be included to provide important information about topics other than safety factors.  These findings should not be read as apportioning blame or liability to any particular organisation or individual.

From the evidence available, the following findings are made with respect to the collision with terrain involving Kawasaki 47G, VH‑BEU, 24 km north of Katherine Tindal Airport, Northern Territory on 11 September 2024. 

Contributing factors

• The right exhaust collector was found to have developed a significant crack, which likely resulted in engine power loss during flight.
• The pilot was unable to cushion the landing during termination of the autorotation, likely due to low rotor RPM, resulting in the helicopter colliding with terrain.

Sources and submissions

Sources of information

The sources of information during the investigation included:

• the pilot and passengers of the accident flight
• the operator
• the maintainer for VH-BEU
• Civil Aviation Safety Authority
• accident witness
• OzRunways data from the pilot’s iPad
• Bureau of Meteorology
• Kawasaki Heavy Industries
• the maintenance facility that conducted the post‑accident engine examination.  

References

U.S. Department of Transportation Federal Aviation Administration Helicopter Flying Handbook, FAA‑H‑8083‑21B (2019).

Lycoming Service Instruction No. 1009BE (2020).

Reciprocating engine and exhaust vibration and temperature levels in general aviation aircraft, U.S. Department of Transportation Federal Aviation Administration (1968).

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 operator
• the maintainer for VH‑BEU
• Civil Aviation Safety Authority
• Kawasaki Heavy Industries
• Textron Lycoming
• United States National Transportation Safety Board
• Japan Transport Safety Bureau

Submissions were received from:

• the pilot of the accident flight
• the operator
• Civil Aviation Safety Authority

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

The ATSB conducted a basic examination of the helicopter wreckage on the hotel roof and within the hotel grounds. The helicopter was subsequently transported to a secure facility where a detailed examination was carried out (Figure 5).

Figure 5: Examination of wreckage

Image source: ATSB.

The helicopter’s cockpit, systems and engine were severely damaged by the impact and post‑impact fire. Within the limitations of the available evidence, there were no indications of in‑flight fire or defects.

• The absence of noteworthy damage to the helicopter’s skids indicated that the helicopter did not impact the hotel roof in an upright position.
• There was no evidence of the main rotor contacting the tail boom, which remained intact.
• Marks on one of the engine oil coolers indicated that the engine and ring gear were rotating at the time of impact.
• Where possible, continuity was established with the main rotor, tail rotor drives and flight controls.
• Main rotor blade damage was indicative of the engine driving the main rotors at a high-power setting.
• The helicopter was fitted with bladder fuel tanks, which were breached during the accident sequence, but it was not possible to assess how the tanks were breached.

A rotor blade tip shattered the window of the room underneath the accident site (Figure 6), and a section from the same rotor blade destroyed the window of an adjacent room (Figure 7).

Figure 6: Hotel room damage

Image source: ATSB.

Figure 7: Hotel adjacent room damage

Image source: ATSB.

Safety analysis

The flight was an unauthorised but purposeful act, however the ATSB did not determine the reason the pilot elected to conduct the flight. The ATSB can conclude from the available evidence that there were no airworthiness factors with the helicopter that likely contributed to the accident. 

The Civil Aviation Safety Authority has put in place regulations designed to ensure the safety of flight. The pilot was affected by a significant amount of alcohol before and during the flight. The pilot further increased risk to themselves and those on the ground by conducting the unauthorised flight well below the 1,000 ft allowed for flight over a built-up area. 

While the pilot held a helicopter commercial pilot licence and had experience flying the Robinson R44, the pilot was not approved to fly the operator’s helicopters at any time. Additionally, the pilot did not hold the appropriate rating to fly helicopters at night and had never flown a Robinson R44 at night. 

Aviation transport security regulations are in place to keep unauthorised persons out of airports. However, as a ground crew of the operator, the pilot was authorised to have access to the helicopter at Cairns Airport and took advantage of that access. Further, based on the strobe lights being turned off, it was apparent that the pilot was wanting to conceal the departure from the airport from air traffic control and airport staff.

Findings

ATSB investigation report findings focus on safety factors (that is, events and conditions that increase risk). Safety factors include ‘contributing factors’ and ‘other factors that increased risk’ (that is, factors that did not meet the definition of a contributing factor for this occurrence but were still considered important to include in the report for the purpose of increasing awareness and enhancing safety). In addition ‘other findings’ may be included to provide important information about topics other than safety factors.  These findings should not be read as apportioning blame or liability to any particular organisation or individual.

From the evidence available, the following finding is made with respect to the collision with building involving Robinson R44 II, VH-ERH, Cairns, Queensland on 12 August 2024. 

Contributing factors

• For reasons unknown, pilot actions resulted in a collision with a building while conducting an unauthorised and unnecessary flight, while affected by alcohol, late at night and at low heights over a built-up area, and without night flying endorsements.

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 2024 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.