The Australian Transport Safety Bureau (ATSB) is alerting owners and operators of Vulcanair/Partenavia P.68 aircraft of a European Union Aviation Safety Agency (EASA) proposal to issue an airworthiness directive (PAD) to mandate an inspection of the aircraft’s upper rudder hinge.

The proposed AD, which was issued in October, would mandate inspections of the hinge in accordance with Service letter 23, revision 2, dated 29 September 2021(Opens in a new tab/window) and the aircraft’s maintenance manual.

It follows the ATSB’s publication of an Occurrence Brief report into a flight control system failure involving a Vulcanair P.68C near Brisbane, Queensland, on 11 April 2021. As the aircraft taxied to the apron after the flight, the pilot had difficulty controlling the aircraft’s direction and advised that the rudder seemed jammed.

A post-flight inspection revealed that the top rudder hinge had failed.

The PAD is applicable to all P.68 Victor, P.68B Victor, P.68R Victor, P.68C, P.68C-TC, P.68 Observer, P.68 Observer 2 and P.68TC Observer aircraft.

Consultation on the PAD closed on 18 November, but any follow-up enquiries regarding the proposed directive can be referred to EASA’s Safety Information Section, Certification Directorate via email ads@easa.europa.eu.

Read the Occurrence Brief (AB-2021-013): Flight control system failure, Vulcanair P.68C, near Brisbane, Queensland, on 11 April 2021

Key points:

• During a low-level geophysical survey flight, an overstress fracture due to a fatigue crack in a Cessna 210’s wing carry-through spar structure resulted in the separation of the right wing;
• Relevant Cessna 210 aircraft have since been subject to eddy inspection requirements to assess for fatigue and the application of a corrosion preventative coating, however the ATSB is recommending further safety action be taken;
• Cyclic loads induced by the low-level survey flight profile are significantly greater than those associated with the higher-level flight profile originally intended for the aircraft type.

The Australian Transport Safety Bureau has made a formal recommendation to the manufacturer of the Cessna 210 aircraft to further address the risk of fatigue cracking within the aircraft’s carry-through structure.

The safety recommendation forms part of the ATSB’s final report from its investigation into the 26 May 2019 collision with terrain of a Cessna T210M which was conducting low-level geophysical survey work about 25 km north‑east of Mount Isa, Queensland.

The aircraft, with a pilot and observer on-board, was operating at a height of 193 ft above ground level and a speed of 147 kt when its right wing separated in flight, leading to a rapid loss of control. The aircraft collided with the ground, and both crewmembers were fatally injured.

Relevant components of the aircraft were subject to detailed examination at the ATSB’s technical facilities in Canberra where it was found that relatively minor corrosion near a highly-stressed location on the lower surface of the wing spar carry-through had progressed into the aluminium alloy structure, initiating a fatigue crack. The crack propagated to a critical size resulting in an overstress fracture of the remaining wing carry-through structure material and separation of the right wing.

This information was immediately communicated to the aircraft manufacturer, Textron Aviation (which now owns Cessna), and Australian and US aviation regulators, and resulted in a number of initial safety actions.

These included Textron issuing service bulletins to owners of relevant Cessna 210 and Cessna 177 aircraft on 24 June 2019 requiring a one-off inspection of the carry‑through structure and communication of inspection findings to the manufacturer, and a US Federal Aviation Administration (FAA) Airworthiness Directive issued on 21 February 2020 requiring the visual and eddy current inspections of the carry-through spar lower cap along with the application of a corrosion preventative coating of certain model Cessna 210 aircraft.

At the time of finalising the ATSB’s investigation report, the FAA and Textron Aviation had received 1,119 reports from Cessna 210 owners/operators who had undertaken the visual and eddy current inspections of the carry-through spar on their aircraft. Of these, 499 reported corrosion and 68 carry‑through structures were removed from service.

Textron has advised the ATSB that it would be undertaking a fatigue analysis of the C210 wing spar carry-through in its original configuration to determine whether a modified inspection program or life limit is necessary. Textron has also advised the ATSB that it is working on a certification program to install a new spar in the C210 with an updated configuration and material.

“The ATSB acknowledges the significant safety actions taken to date by the manufacturer and regulators as a result of this accident and the ATSB’s investigation, and notes that these measures have addressed the short-term risk of further similar failures,” said ATSB Chief Commissioner Angus Mitchell.

“Further, the ATSB welcomes Textron’s ongoing efforts to address the risk of cracking in wing spar carry-through structure of Cessna 210 aircraft used for low-level geophysical survey operations. However, the ATSB remains concerned by the indefinite nature of the manufacturer’s proposed analysis and certification program and recommends that further action be taken to address this safety issue.”

In 1992, Cessna had introduced a continued airworthiness program for the Cessna 210 which included repetitive eddy current inspection for cracking of the carry-through structure. This flight-hours based inspection was more stringent for aircraft being used for low-level surveys.

Eddy current inspection is a form of non-destructive testing which can detect flaws in the internal consistency of certain types of metals.

However, following an assessment of historical data in 2011, Cessna replaced this inspection with a visual corrosion inspection, on a three-yearly frequency for all operation types, irrespective of hours flown.

“Had the previous flight-hour based eddy current inspection schedule remained in place, it is almost certain that the fatigue crack within the wing spar carry-through would have been detected before this accident occurred,” Mr Mitchell said.

The accident aircraft had accumulated 6,241 flight hours in the six years leading up to the accident, and had been operated exclusively as a geophysical survey aircraft during that time. In total the aircraft had accumulated 12,175 flight hours.

As part of the investigation the ATSB, in cooperation with the operator, undertook data gathering using an instrumented Cessna 210N to determine in-flight loads associated with the geophysical survey flight profile. Data from 95 flights over a period of 10 weeks during autumn in 2020 was sampled and analysed.

“The ATSB’s analysis showed that cyclic loads induced by the low-level survey flight profile were significantly greater than those associated with the higher-level flight profile originally intended for the aircraft type, and this probably increased the risk of a fatigue-related structural failure,” Mr Mitchell said.

“Even when flying within operational limits, if an aircraft is operated in a flight profile for which it was not originally intended, its structure can fatigue more rapidly.

“The ATSB cautions all geophysical survey aircraft operators that the terrain following flight profile may significantly increase aircraft fatigue damage accumulation.”

The investigation also determined that the airframe and system modifications incorporated into the accident aircraft did not significantly increase the fatigue damage accumulated by the wing spar carry-through structure.

Read the final report: In-flight break-up involving Cessna T210M, VH-SUX, 25 km north-east of Mount Isa Airport, Queensland, on 26 May 2019 | ATSB

Key Points:

• Two of five landing gear downlock pins were not removed after a Boeing 787 was towed to the gate and prior to departure;
• Pins were also not identified during subsequent pre-flight inspections
• Flight crew were unable to raise landing gear and the aircraft returned to Sydney;
• ‘Remove before flight’ streamers are visual reminders to remove covers and lockout devices prior to flight, but can be subject to varying environmental conditions that can reduce their visibility

Two downlock pins that had not been removed from a Boeing 787’s main landing gear following towing, nor identified during subsequent pre-flight inspections, prevented the aircraft’s main landing gear from retracting after take-off, an Australian Transport Safety Bureau investigation report outlines.

On 21 June 2021, the Qantas Boeing 787-9 departed Sydney for Perth with 106 passengers and 13 crew on board.

During the initial climb, when the flight crew selected UP on the aircraft’s landing gear lever, they received a warning indicating that neither main landing gear had retracted to the ‘up and locked’ position.

Actioning the aircraft’s electronic checklist did not resolve the issue.

The flight crew then selected the landing gear lever to DOWN, resulting in a positive gear extension indication, and the aircraft was returned to Sydney for an uneventful landing.

Subsequent inspections identified that two of the aircraft’s five landing gear downlock pins had not been removed after it had been towed to the domestic terminal aircraft bay in preparation for the flight.

The pins prevented the main landing gear from retracting after take-off.

“Pins are inserted into the nose and main landing gear when the aircraft is on the ground to prevent inadvertent gear retraction during maintenance or towing,” ATSB Director Transport Safety Stuart Macleod explained.

“In this case two of the pins – one of the two for each main landing gear – had not been removed after towing and prior to the flight. In addition, subsequent preflight inspections by the flight and dispatch crew did not identify that the pins remained in place prior to departure.”

Attached to each pin was a red ‘remove before flight’ streamer. One streamer on each main landing gear was visible in CCTV footage of the aircraft being towed to its bay prior to the flight.

The pins attached to these two streamers were removed before departure, while the second gear pin on each main landing gear was missed. The missed gear pin streamers may have been stuck on the gear, from a combination of grime and the recent wet and windy conditions.

Post-incident inspection found all four main gear pins’ streamers to be in place, but dull and frayed. Their condition prior to the flight could not be conclusively determined.

“‘Remove before flight’ streamers are visual reminders to remove covers and lockout devices prior to flight, but can be subject to varying environmental conditions that can reduce their visibility,” Mr Macleod said.

“Expectation can also affect your ability to identify these warning devices. If you are not expecting to see a ‘remove before flight’ streamer, you are significantly less likely to detect one that is present.

“The same principle can also prevent the discovery of damaged and/or missing components.”

The 787 has five landing gear pin locations: one in its nose gear, and two in each of its main landing gear, whereas other types in the Qantas fleet such as the A330 and 737 have three pins: one in the nose gear, and just one in each of the main landing gears.

The two members of the tow crew who had removed three of the five gear pins – one from the nose gear, and one each from the left and right main landing gear – had not towed a 787 prior to the occurrence.

Moreover, once removed, on the A330 and 737 the gear pins are stored on the flight deck, whereas on the 787 they are stored in the aircraft’s electrical equipment centre (EEC), just aft of the nose gear.

When stowing the three removed gear pins in this incident, the tow crew team member reached up from a ladder below, and so was unable to see inside the stowage compartment, where there were receptacles for five gear pins in total.

After the occurrence, Qantas advised it was working to relocate the gear pin stowage on its 787s to the flight deck, to bring them in line with other aircraft in its fleet, and to enable ease of access to verify pin stowage.

The operator also distributed a memo to its engineering, flight and ramp staff to highlight the quantity and location of the gear pins on the Boeing 787, and the importance of following the documented ramp, pre-flight and dispatch procedures.

The memo also emphasised the importance of checking the pin locations, rather than relying on ‘remove before flight’ streamers for identification of pins, after towing.

Read the final report: Landing gear retraction deactivation and return involving a Boeing 787, VH-ZNH, near Sydney Airport, New South Wales, on 21 June 2021

Key points

• Fracture of the propeller bolts was likely related to a loss of bolt tension
• Emergency training practice and recurrence increases the likelihood of pilots achieving a safe outcome
• The incident highlights the importance of pilots remaining vigilant to transient or persistent changes to the normal operation of their aircraft.

The propeller of a Jabiru aircraft separated in-flight due to fractured propeller bolts likely due to a loss of bolt tension, an ATSB investigation has found.  

A student pilot had departed on a training area solo flight in the Jabiru J170-C aircraft from Muchea Greenside airfield, north of Perth, on 22 December 2021. On return to the airfield, during the downwind leg of the circuit, the pilot commenced configuring the aircraft for landing when a vibration from the engine was felt.

The engine gauges read as normal and the vibration reduced with throttle reduction.

Shortly after, while on final approach, the pilot observed emus crossing the runway around the normal touchdown point and conducted a go-around. While on climb at around 800 feet, there was a loud ‘bang’ and the pilot observed that the propeller had separated from the aircraft.

The pilot elected to land ahead and conducted an uneventful forced landing in a paddock, approximately 2.5 km from the end of the runway. The aircraft suffered minor damage during the landing, and the pilot was uninjured.

“The ATSB’s investigation found that the propeller separated as a result of fracture of the propeller bolts that was likely related to a loss of bolt tension,” said ATSB Director Transport Safety Dr Stuart Godley.

“However, as the propeller was not able to be found, the mechanism for the loss of bolt tension was not determined.”

The investigation also noted that the student pilot’s actions were positively influenced by having recently undertaken several hours’ worth of flight emergency training, contributing to the safe outcome.

“When faced with an in-flight emergency, emergency training practice and recurrence will increase the likelihood of pilots achieving a safe outcome,” Dr Godley said.

The incident also highlights the importance of pilots remaining vigilant to transient or persistent changes to the normal operation of their aircraft, which may be indicative of an impending failure of a critical component or system.

“Landing as soon as practicable and having the aircraft inspected is a prudent course of action.”

Dr Godley noted that the ATSB did not typically investigate incidents and accidents involving recreational category aircraft. However, as Australia is the state of design and state of manufacture for the Jabiru aircraft, and the same aircraft model are registered with CASA and is also operated internationally, the ATSB conducted the investigation to determine if there were broader lessons for the aircraft type.

Read the final report: In-flight propeller loss involving Jabiru J170, 24-7496, near Muchea/Greenside ALA, Western Australia, on 22 December 2021

Key points:

• Biplane aerobatic aircraft sustained an in-flight break-up shortly after departure from Caboolture;
• Preliminary technical examination determined that two of the eye bolts that attached the upper wings to their supporting struts had failed due to fatigue cracking;
• ATSB has issued a Safety Advisory Notice to other owners and operators of the Acroduster aircraft type to raise awareness of the fatigue cracking.

Technical examinations as part of the Australian Transport Safety Bureau’s on-going investigation into the in-flight break-up of an Acroduster aerobatic biplane near Bribie Island on 18 August have determined that two eye bolts used to secure the aircraft’s upper wings had failed due to fatigue cracking.

The two-seat home-built Acroduster aerobatic aircraft had departed Caboolture on the morning of 18 August to conduct an aerobatic flight with the pilot, the sole occupant, on board.

A short time later the crew of a helicopter operating nearby noticed red and white debris falling from the sky before sighting the main wreckage of the biplane inverted in tidal wetlands in the Pumicestone Passage, adjacent to Bribie Island. The pilot was found to have been fatally injured.

Investigators from the ATSB’s Brisbane office deployed to the site later that day.

“It was evident to our investigators once they had arrived on site that the aircraft had sustained an in-flight break-up, with the wreckage trail distributed over a distance of about 2.4 km,” said ATSB Chief Commissioner Angus Mitchell.

The main wreckage consisted of the fuselage and tail as well as the outer-wing sections, which had remained attached to the fuselage by bracing wires. The remainder of the wing sections had separated from the aircraft.

The aircraft was recovered from the accident site by barge and taken to a secure facility for a detailed examination.

“Preliminary examination of the main wreckage revealed that two of the eye bolts that attached the upper wings to their supporting struts had failed due to fatigue cracking,” said Mr Mitchell.

The ATSB has already notified the owner of the only other Acroduster in Australia of the issue, and has advised its counterpart agency in the US, the National Transportation Safety Board, so that the information can be shared with the US Federal Aviation Administration, the US Experimental Aircraft Association and the kit plane design/material provider.

Additionally, the ATSB has also now issued a Safety Advisory Notice to alert pilots, owners and maintainers of the Stolp Acroduster (both the SA-700 Acroduster and SA-750 Acroduster) to check the condition of their aircraft.

“While our investigation is on-going, the Safety Advisory Notice serves to inform operators of this type internationally of this discovery so that they can take appropriate action to ensure that their aircraft remain airworthy,” said Mr Mitchell.

It is not clear how many aircraft may be affected by the Safety Advisory Notice, however approximately 130 Acroduster aircraft have been built since plans for the types were made available in the early 1970s.  

The accident aircraft, registered VH-YEL, had been built in the United States from plans supplied in 1976 and first flew in 1981. The aircraft was shipped to Australia in 2003 and had accumulated 717 flight hours at the time of the accident.

Mr Mitchell noted today’s preliminary report details basic factual information determined in the investigation’s early evidence collection phase.

“As the ATSB’s investigation progresses, transport safety investigators will undertake a metallurgical examination of the entire upper-wing attachment hardware and structure; review the aircraft’s operational history and maintenance procedures and inspection requirements; and further analyse radar data,” he said.

A final report, which will detail analysis and findings, will be released at the conclusion of the investigation.

Read the preliminary report: In-flight break-up, Stolp Acroduster II SA-750, VH-YEL, 16 km north-east of Caboolture airfield, Queensland, on 18 August 2021

Read the Safety Advisory Notice: AO-2021-032-SAN-001: Are your wing attachment points serviceable?

The forced landing of a turbine-powered Cessna 210 about 560 metres short of the runway threshold following an engine failure from flight in icing conditions highlights the importance of proper pre-flight planning, according to an ATSB investigation.

The US-registered Cessna P210N Silver Eagle, a pressurised Cessna P210N re-engined with a Rolls-Royce M250 turbine, had departed Sydney’s Bankstown Airport for a private flight under instrument flight rules to Hobart’s Cambridge Airport on 19 December 2019. The pilot and a single passenger were onboard.

The flight was planned and conducted through forecast icing conditions although the aircraft was not certified or equipped for flight in known icing. It entered icing conditions about half an hour into the flight, shortly after reaching the cruise altitude of about 18,000 ft.

“Flight through icing conditions for an extended period resulted in significant accumulation of ice on the airframe,” ATSB Director Transport Safety Stuart Macleod said.

The pilot continued to operate in icing conditions for an extended period of time before exiting those conditions and descending to 16,000 ft. Subsequently, the pilot deactivated the propeller de-ice and engine ice-protection systems, which in turn led to a flameout from ice ingestion.

“Attempts to restart the engine were unsuccessful, most probably because of a phenomenon known as rotor lock – where rapid and differential cooling of the engine’s components temporarily prevents it from rotating,” Mr Macleod explained.

Without engine power, the pilot conducted a glide approach towards Moruya Airport on the New South Wales South Coast.

“While the pilot was able to get near the airport, the subsequent manoeuvring compromised the ability to remain visual with the airport and assess the glide approach, resulting in the aircraft being too low to reach the most appropriate runway,” Mr Macleod said.

“Subsequent distraction led to a misjudged approach to the remaining runway options.”

The aircraft impacted terrain about 560 m north of the runway threshold and was destroyed. The pilot was seriously injured, and the passenger sustained minor injuries.

“This investigation highlights that thorough knowledge of an aircraft’s limitations and systems, in combination with an understanding of hazardous weather and aviation meteorological products, is critical to safe and effective flight operations,” said Mr Macleod.

“Icing conditions can be extremely hazardous to aircraft. Every icing encounter, to some extent, is unique and unpredictable.”

Mr Macleod stressed that pilots should carefully evaluate all available relevant meteorological information when determining whether icing conditions are likely along the planned flight path.

“Where the aircraft is not certified or equipped to operate in icing conditions, any ice-protection systems on the airframe, propeller, or engine should be regarded as a means to provide time to exit unexpected icing conditions, not to continue to operate in those conditions.”

In addition, the ATSB investigation emphasises that practice and proficiency in simulated forced landings and power-off approaches can improve the likelihood of successfully managing emergency situations.

“Although forced landings can occur in a variety of circumstances, in general, pilots should focus on remaining visual with the intended landing area in order to accurately assess the aircraft’s performance in glide and reach key decision points to refine the course of action,” Mr Macleod said.

The investigation also identified a number of other factors associated with pre‑flight preparation and the operation of the aircraft and its systems.

Finally, the ATSB also found that the seatbelts and shoulder harnesses worn by the pilot and passenger probably reduced the extent of their injuries, and the prompt attendance of nearby paramedics further reduced their risk.

Read the final report: Engine failure and collision with terrain involving Cessna P210N, N210BA, near Moruya Airport, New South Wales, on 19 December 2019

A rail maintenance contractor has amended its processes for on-tracking road-rail vehicles after two RRVs travelled about three kilometres without track protection, an Australian Transport Safety Bureau investigation report notes.

On 10 June 2021, two RRVs operated by SPENO Rail Maintenance Australia on-tracked at the Binney Road level crossing at Crystal Brook, South Australia, to undertake ultrasonic rail flaw detection.

Prior to on-tracking, the RRV crew’s track worker level 2 – responsible for track protection – had contacted the network controller and requested protection limits from Signal 24 Crystal Brook.

While Binney Road level crossing is in the town of Crystal Brook, the signal the track worker was intending to reference was actually Signal 24 Rocky River on the track operator’s network plan. Signal 24 Crystal Brook is about 3 kilometres further down the line.

After clarifying with the track worker that the RRVs intended to travel down the Westbound Mainline, the network controller applied blocking facilities at Signal 24D Crystal Brook.

“This request and confirmation for protection limits from Signal 24D Crystal Brook instead of Signal 24 Rocky River meant the two RRVs on-tracked in an area without protection from other rail traffic,” ATSB Director Transport Safety Dr Stuart Godley said.

“They subsequently travelled for about three kilometres before reaching a set of points prior to the section of track where protection had been applied.”

The network controller recognised the safeworking breach when the RRV’s track worker requested the points be set for the Westbound Mainline so they could enter the intended route to continue ultrasonic testing.

“When the protection was arranged, there was no confirmation between the track worker and the network controller of specifically where the RRVs were going to be put on-track,” Dr Godley explained.

This incident highlights the importance of identifying the location that travel or work on track will commence.

“Competent workers should provide all the information required for network controllers to identify and confirm that protection limits adequately cover the intended work site,” Dr Godley said.

“Confirmation of location is especially important for providing blocking protection for RRV movements.”

Read the final report: Safeworking Breach of Road-Rail Vehicles, Crystal Brook, South Australia, on 10 June 2021

A collision between a bulk carrier and a fishing vessel off Port Adelaide highlights the importance of navigation watchkeepers on vessels utilising all available means to maintain a proper lookout, an Australian Transport Safety Bureau investigation stresses.

Just after 0430 on the morning of 29 February 2020, the fishing vessel Sandgroper collided with the 108-metre self-discharging bulk carrier Accolade II, just off the entrance to Port Adelaide, in darkness and clear visibility conditions.

Sandgroper sustained significant structural damage to its starboard bow, while Accolade II sustained only minor damage to its deck structures and railings on the ship’s starboard side. In addition, Sandgroper’s anchor was found lodged in Accolade II’s deck railings.

There were no reported injuries on either vessel.

“In the time leading up to the collision a proper lookout using all available means was not being maintained on board either vessel,” ATSB Director Transport Safety Stuart Macleod said.

“Consequently, neither was aware of the risk of the collision posed by the other, until shortly before the collision, when it was too late to take effective avoiding action.”

Mr Macleod noted the navigation bridge team onboard Accolade II did not have a complete appreciation of the traffic situation, and of the risk of collision outside the port channel, before they exited the channel prior to the collision.

“In particular, effective use was not made of the ship’s radar and a dedicated lookout was not posted in darkness,” he said.

“And while Sandgroper’s skipper did initially sight Accolade II while it was still in the channel, a proper lookout was not subsequently maintained using all available means, including radar and monitoring the port’s working channel on the radio.”

As a result, Sandgroper’s skipper was not aware that Accolade II had exited the channel, and that a close quarters situation was developing.

“Collisions between trading ships and small vessels continue to occur around the Australian coast, and the safety of fishers and people in small boats continues to be of real concern to the ATSB,” Mr Macleod said.

“ATSB investigations have consistently shown that keeping a proper lookout by all available means – including radar, radio, and automatic identification system (AIS) transceiver – in accordance with the collision regulations, could have prevented most of these collisions.”

While Sandgroper was not required to be fitted with an AIS transceiver, it would have improved the vessel’s detectability.

“An AIS would have increased the chances of the fishing vessel being detected by Accolade II’s bridge team in sufficient time to avoid collision.”

Sandgroper has subsequently been fitted with an AIS, while the managers of Accolade II have advised the ATSB that a navigational audit of the ship’s operations has since been conducted, resulting in several recommendations to improve the ship’s bridge resource management practices.

Read the final report: Collision between Accolade II and Sandgroper, off Port Adelaide, South Australia, on 29 February 2020

Key points

• A pilot attempted to take-off from a closed runway at Gunnedah after failing to check the local NOTAM in pre-flight planning; 
• At the time of the incident no works safety officer was on-site, and there was no ground-based closed runway signage in place; 
• Airport operator was not aware of recent updates to Manual of Standards for Aerodromes, as email address registered with CASA was not being monitored. 

A twin-turboprop aircraft sustained substantial damage when attempting to take-off from a runway that had been closed for repair works, an Australian Transport Safety Bureau investigation details. 

The Fairchild Industries SA226-T Merlin had landed at Gunnedah, northern NSW on the afternoon of 19 August 2020, and was parked there overnight.  

The following morning, in line with a NOTAM published the previous day closing the runway from 0700 to enable runway repair works, a work crew had excavated two holes from the runway pavement (measuring 3 m wide by 5 m long and about 30 cm deep). 

That afternoon, at about 1230 while the work crew was off-site from the airport during their lunchbreak, the Fairchild pilot commenced a take-off run on the runway for a flight to the Gold Coast. 

As the aircraft accelerated, the pilot saw the two rectangular holes excavated from the runway pavement. The pilot attempted to avoid the holes, but they were struck by the aircraft’s left main landing gear. 

“The aircraft sustained damage to its left main landing gear assembly, which resulted in it collapsing, and the left propellor striking the ground,” ATSB Director Transport Safety Dr Stuart Godley explained.  

“The aircraft veered off the runway and came to rest outside the flight strip.” 

The pilot – the sole occupant on board the aircraft – was uninjured. 

“The ATSB investigation found that during pre-flight planning, the pilot had not checked for relevant NOTAMs, including one stating that Gunnedah Airport was closed due to works in progress,” Dr Godley said. 

NOTAMs are accessible via the National Aeronautical Information Processing System (NAIPS) web portal and contain information concerning the establishment, condition, or change in any aeronautical facility, service, procedure, or hazard. 

“An essential component of pre-flight planning is to check all NOTAMs relevant to the planned flight,” Dr Godley said.  

The investigation also found that while the work crew was away on their lunch break there was no works safety officer on site. Further, while a white cross had been placed at the main windsock, visible to aircraft arriving overhead, there were no ground-visible unserviceability markings on the runway.  

Both measures are required by the Civil Aviation Safety Regulations Part 139 Manual of Standards (MOS) for Aerodromes. 

“Aerodrome works staff were not aware of updated MOS requirements that had come into effect seven days earlier, and had interpreted the superseded MOS to not require unserviceability markings if the whole aerodrome was closed,” Dr Godley said. 

The Gunnedah Airport operator had not received notification of the updated MOS because the email included on CASA’s mailing list was for a member of staff who had left the operator. No autoreply, forwarding, or ‘hard bounce’ was in place on the email address, so CASA was not aware the email had not been received. 

“To ensure receipt of correspondence that may affect safety of aircraft operations, aerodrome operators should ensure CASA is provided up to date contact details, particularly following changes to staff,” Dr Godley concluded. 

Read the final report: Take-off from a closed runway involving Fairchild Industries SA226, VH-LDQ, at Gunnedah Airport, New South Wales, on 20 August 2020