ATSB releases Wallan XPT derailment preliminary report.

The Australian Transport Safety Bureau has released the preliminary report from its ongoing investigation into the derailment of XPT passenger train ST23 at Wallan, Victoria on 20 February 2020, in which the driver and assisting qualified worker were fatally injured.

The preliminary report details basic factual information established in the investigation’s early evidence collection phase, including the sequence of events, track information, and data downloaded from the train’s data logger.

“ATSB preliminary reports do not contain findings, identify contributing factors or outline safety issues and actions, which will be detailed in an investigation’s final report,” ATSB Chief Commissioner Greg Hood noted.

The preliminary report confirms that the train, which was travelling from Sydney to Melbourne with six crew, the assisting qualified worker (who joined the train near Kilmore) and 153 passengers onboard, entered a passing loop at Wallan at a speed of more than 100 km/h when the speed limit for entering the loop was 15 km/h.

“Earlier that afternoon, the points at either end of the Wallan loop had been changed from their ‘Normal’ position to their ‘Reverse’ position, which meant that rail traffic, in both directions, would be diverted from the Main Line into the loop track,” Mr Hood noted.

“A Train Notice reflected this change and also specified a 15 km/h speed limit for entry into the loop.”

The train’s data logger showed an emergency brake application was applied a short distance from the points before entering the passing loop.

“This slowed the train a small amount before it entered the turnout travelling at a speed in excess of 100 km/h. The train was not able to negotiate the turnout to the loop track at this speed and derailed. All vehicles derailed excepting the rear power car.”

During the derailment sequence, the lead power car rolled onto its left side and the XPT driver and the accompanying qualified worker sustained fatal injuries. Three passengers were seriously injured and 36 received minor injuries, while five train crew who were in the passenger cars also sustained injuries.

Mr Hood said the preliminary report notes that due to damaged signalling equipment a 24 km section of track between Kilmore East and Donnybrook incorporating Wallan was being managed by an ‘alternative safe working system’, and that the accompanying qualified worker boarded the lead power car near Kilmore and joined the driver as part of the alternative safeworking system.

“The continuing investigation will explore a range of factors, including a detailed examination of the alternative safeworking systems; the operation of the train; the conditions of the track and rolling stock; and crew and passenger survivability including a passenger survey,” Mr Hood noted.

Mr Hood said the investigation is being led by Victoria’s Chief Investigator, Transport Safety (CITS), under delegation from the ATSB, with support from the ATSB as well as New South Wales’ Office of Transport Safety Investigations (OTSI). CITS conducts rail investigations in Victoria on behalf of the ATSB under the Transport Safety Investigation Act 2003.

“I would like to acknowledge the efforts of CITS in particular in working diligently to build a detailed understanding of this accident, and to recognise the support the ATSB and CITS have received from a broad range of stakeholders who have contributed to this investigation’s early phases,” he said.

Mr Hood noted an investigation of this nature and complexity may take more than 18 months to complete.

“However, should any safety critical information be discovered at any time during the investigation, we will immediately notify operators and regulators, and make that publicly known.”

Read the preliminary report: Derailment of passenger train ST23, Wallan, Victoria, on 20 February 2020

Recorded data and recovered components focus of ongoing investigation of fatal collision with water.

Recorded data and recovered components are among the areas of focus for the ongoing investigation into the fatal collision with water of a Cessna 182 light aircraft near Moreton Island in south-east Queensland on 22 January 2020.

The ATSB preliminary report details the aircraft’s flight path in the lead-up to the dual fatality accident. The Cessna 182, registration VH-WNR, had departed Caloundra Airport at 3.30 pm as a private sightseeing flight with the pilot and a passenger on board.

The aircraft flew south over Bribie Island and onto Moreton Island. At 4.06 pm, when the aircraft was overhead Tangalooma, the pilot radioed that he intended to head south to the end of the island and then north up the eastern side of the island.

The ATSB’s preliminary examination of the flight path indicates the aircraft passed the northern tip of the island at about 1,100 ft in a shallow descent and continued towards Flinders Reef. The aircraft’s airspeed and descent remained stable until about 4.25 pm when the descent rate began to gradually increase. The pilot made a MAYDAY call at 4.26 pm east of Flinders Reef while descending through 300 ft at a groundspeed of 115 kt. Air traffic control attempted to establish contact but no further transmissions were received from the aircraft.

Examination of underwater footage of the aircraft showed damage to the cabin indicating the impact with water was unlikely to be survivable.

Initial analysis of radar data points to the aircraft continuing north-east for another 15 to 20 seconds after the transmission before colliding with the water.

An aerial and marine search was initiated, and the aircraft was located on 29 January 2020, north-east of Flinders Reef in about 30 metres of water. The pilot and passenger were not located.

“Examination of underwater footage of the aircraft showed damage to the cabin, indicating the impact with water was unlikely to be survivable,” ATSB Director Transport Safety Dr Mike Walker said.

“Some aircraft components, including the engine and propeller, were recovered with the assistance of the Queensland Police Service and the Queensland National Parks and Wildlife Service. The ATSB is grateful for their valuable assistance.”

Dr Walker said no pre-existing defects were identified during workshop examinations of the engine and propeller but there remains much work to do.

“In addition to the examination of the recovered components, the ongoing investigation will include the examination of the aircraft’s maintenance and operational records as well as video footage of the wreckage, pilot qualifications and medical history and further analysis of recorded radio, radar and engine monitoring data.”

The investigation is still in early phases and that the ATSB’s safety analysis and findings will be published in the final investigation report.

“Should a critical safety issue be identified during the course of the investigation, the ATSB will immediately notify relevant parties so appropriate safety action can be taken,” Dr Walker said.

Read the preliminary report: Collision with water involving Cessna 182, VH-WNR, 6 km north-west of Moreton Island, Queensland, on 22 January 2020

ATSB releases Jumperkine freight train collision preliminary report.

Functionality of locomotive braking control and vigilance systems, driver-only operations, and human performance considerations such as fatigue are among the areas of interest for the Australian Transport Safety Bureau’s ongoing investigation into a fatal collision between freight trains at Jumperkine in Western Australia.

At about 2am on 24 December 2019, Pacific National freight train 7MP5 collided with the rear of stationary grain train 2K66. The freight train’s lead locomotive was substantially damaged with a significant amount of grain entering the cabin, and the driver was fatally injured.

The ATSB’s preliminary report details the accident's sequence of events, established using a range of sources including the freight train’s data logger, and notes that when the grain train had come to a stop behind a red signal at Jumperkine, the freight train was 14.5 km behind and approaching Jumperkine.

Nearing Jumperkine the freight train passed a signal set at caution (yellow), then a Temporary Speed Restriction Ahead sign warning of a 30 km/h speed restriction in 2,500 metres. Shortly after the driver acknowledged an alert from the train’s vigilance* system, the train passed a Jumperkine signal set at stop while travelling at a speed of about 72 km/h.

The preliminary report then details that 60 metres after the stop signal, train 7MP5 passed the subsequent Temporary Speed Restriction Start sign, with the driver applying the service brake about three seconds later.

The train’s speed gradually reduced as it travelled around a sweeping left hand curve and onto a straight section of track. It is likely that the rear of the grain train came into view at about this point and an emergency brake application was made.

About 13 seconds after the emergency brake application freight train 7MP5 collided with the rear of the grain train 2K66.

Shortly before the collision, a network controller had attempted to contact the driver of 7MP5 after a Signal Passed at Danger or SPAD alarm was triggered, but there was no response. 

Investigators will examine the functionality of the relevant locomotive’s braking controls and vigilance system and undertake further analysis of available event data recorders and video recordings.

“ATSB preliminary reports detail basic factual information established in the investigation’s early evidence collection phase and do not contain findings, identify contributing factors or outline safety issues and actions, which will be detailed in an investigation’s final and any interim reports,” noted ATSB Director Transport Safety Dr Stuart Godley.

“In the coming months transport safety investigators will examine the functionality of the locomotive’s braking and vigilance control systems and undertake further analysis of event data recorders and video recordings,” Dr Godley said.

“Other areas of further investigation include risk controls associated with collisions and Signals Passed At Danger authority exceedances, a review of driver-only operations, human performance controls and well as factors affecting human performance such as fatigue, health and fitness.

“A final report will be released at the conclusion of the investigation, however, should a critical safety issue be identified during the course of the investigation, the ATSB will immediately notify relevant parties so appropriate safety action can be taken,” Dr Godley noted.

The preliminary report notes that Pacific National has proactively taken a number of safety actions since the accident, including adding a second crew member to trains operating between midnight and 6 am.

Read the preliminary report: Collision between freight trains 7MP5 and 2K66, at Jumperkine, Western Australia, on 24 December 2019

*A train’s vigilance system is a safety device that operates in case of incapacitation of the train driver for any reason. The system will react by directly initiating an emergency brake application if an acknowledgment input is not received within a specified time increment (in this case 50 seconds).

Landing gear wheel failure results in inspection, maintenance procedure changes.

After a wheel on one of its Boeing 737s failed, Virgin Australia implemented new landing gear wheel inspection requirements, while the wheel manufacturer, Safran, updated the relevant component maintenance manual.

The wheel failure event occurred on 4 January 2017 when the 737-800 was holding on taxiway Brisbane Airport B3 when the crew heard a loud noise they thought was a burst tyre. The crew attempted to taxi back to the gate, but were held short when an engineer observed that the left main landing gear main wheel assembly had failed.

The flight was cancelled and passengers disembarked, however the aircraft could not be jacked and towed via the axle due to the damaged wheel. Instead, wing jacks were used to allow a double wheel change on the tarmac. The aircraft was then towed to a maintenance facility for examination.

…There were no mandated inspections suitable for detecting such loosening.

An ATSB investigation found that the wheel had ruptured due to tie bolt assemblies having loosened while in service. This allowed the two wheel halves to move relative to each other, resulting in a fatigue crack and eventual wheel rupture. The loosening was most likely due to the presence of anti-seize compound between the wheel halves, which affected the clamping forces.    

“This incident highlights the importance of compliance with all aspects of manufacturers’ maintenance procedures, including the appropriate application of anti‑seize,” said ATSB Director Transport Safety Stuart Macleod. “This is especially important if, as in this case, there is no simple means of detecting the effect that such excess product can have on fastener security.”

The ATSB found that while the bolt assemblies on this single-web wheel-type were more prone to in-service loosening than dual-web wheels, there were no mandated inspections suitable for detecting such loosening. There were also no mandated risk controls to prevent loosening or subsequent rupture.

Virgin has advised that in response to this incident, it has implemented regular inspections to identify and prevent the loosening of tie bolt assemblies. Safran, the wheel manufacturer, updated the wheel’s component maintenance manual with more detailed instructions for applying anti-seize compound.

Finally, Boeing advised 737 NG operators of two possible courses of action to address the issue of potential wheel failures based on two optional service bulletins that it had in place prior to the occurrence.

The particular wheel type was installed on approximately 2,000 737 NG aircraft in service worldwide. Boeing has delivered approximately 7,000 737 NG aircraft in total.

Read the final report: Main landing gear wheel failure during taxi involving Boeing 737, VH-VUH, at Brisbane Airport, Queensland, on 4 January 2017

Weather a focus in ongoing investigation into fatal collision with terrain. ATSB preliminary report.

Meteorological conditions and pre-flight preparation are among the areas of focus in the ATSB’s ongoing investigation into the fatal collision with terrain of an amateur-built Wittman Tailwind light aircraft on 12 January.

The ATSB’s preliminary report details that the aircraft, registered VH-TWQ, had departed Evans Head, NSW, bound for Boonah, Queensland, with the pilot and one passenger on board, operating under visual flight rules (VFR).

The report notes the aircraft flew in a north-westerly direction towards Boonah before commencing a 180 degree turn overhead the township of Kyogle and diverting to the south to Casino. After about 45 minutes on the ground, the aircraft departed Casino to continue the flight to Boonah.

Approximately 15 minutes later, the aircraft was flying over the Tooloom National Park when recorded data shows it commenced a left turn before shortly afterwards colliding with terrain. The pilot and passenger were fatally injured and the aircraft was destroyed.

Due to the damage to the airframe, the aircraft’s attitude when it entered the tree canopy could not be determined.

Subsequent examination of the wreckage by ATSB transport safety investigators indicated that the aircraft collided with a number of trees before coming to rest on the rainforest floor. The aircraft’s structure was substantially disrupted, with the wreckage trail covering a length of about 120 metres.

“The ATSB’s ongoing investigation will include examination of the meteorological conditions and pre-flight preparation,” said ATSB Director Transport Safety Stuart Macleod. “Investigators will also examine the recovered wreckage, the aircraft’s performance characteristics and recorded flight data, and analyse the pilot’s qualifications and experience and the aircraft’s maintenance documentation and operational records.”

Mr Macleod stressed that this investigation is still in its early stages, and the ATSB will not publish its findings until the final investigation report is released.

“However, the ATSB does note that meteorological conditions and preflight planning are areas of focus for this investigation, and weather-related general aviation accidents remain one of the ATSB’s most significant causes for concern in aviation safety.”

To reinforce to visual flight rules pilots the dangers of flying into instrument meteorological conditions – IMC, and to highlight the actions they can take to avoid a weather-related accident, the ATSB has developed a safety promotion campaign titled ‘Don’t push it, DON'T GO – Know your limits before flight’.

“‘Don’t push it, DON'T GO’ highlights three key messages: the importance of thorough pre-flight planning and having alternate plans, that pressing on where there is the possibility of entering IMC carries a significant risk of spatial disorientation, and the value of using a ‘personal minimums’ checklist to help manage flight risks,” Mr Macleod said.

Flying into poor weather without the training and experience to do so can rapidly lead to spatial disorientation when the pilot cannot see the horizon.

“The brain receives conflicting or ambiguous information from the sensory systems, resulting in a state of confusion that can rapidly lead to incorrect control inputs and a resultant loss of control of the aircraft,” Mr Macleod noted.

“For pilots who fly under VFR, conducting thorough preflight planning and working to a personal minimums checklist aids sound decision-making both prior to take-off and during flight when faced with marginal weather or darkness.”

Findings from ATSB investigations into aircraft accidents where a VFR pilot flew into IMC are published in the ATSB’s recently updated Accidents involving pilots in Instrument Meteorological Conditions publication, re-released as part of the Don’t push it, DON’T GO campaign.

Read the preliminary report: VFR into IMC and loss of control involving Wittman Tailwind, VH-TWQ, Tooloom National Park, New South Wales, on 12 January 2020

With the devastating fires and floods, the ATSB acknowledges the contribution of many aviators.

With the devastating fires and floods affecting many areas across Australia in recent months, the Australian Transport Safety Bureau (ATSB) acknowledges the valuable contribution by many aviation operators who have safely supported communities in their times of need.

With unprecedented bushfires burning since September 2019, and more recently areas of severe flooding after a week-long down pour of welcoming rain, a high tempo of civil and military aviation activity has provided vital support during these natural disasters.

ATSB Chief Commissioner Greg Hood said pilots from a range of specialist sectors have helped assist impacted areas across the country to get back on their feet.

“I would like to acknowledge the continued safe work being done by so many people in the aviation industry – both civil and military – who have worked together during this unprecedented summer,” Chief Commissioner Hood said. “Flying in the adverse conditions that we’ve seen predominately along our east coast, whether it’s fighting the fires or supporting communities from the floods, is very challenging and with elevated levels of risk.

“As we all mourn the loss of three American aircrew who were tragically killed in late January when their C-130 Hercules collided with terrain at Peak View near Cooma, NSW, it is important for all of us in aviation to continue to safely serve our nation during this period of natural disasters.”

Australians are no strangers to bushfires and floods. The Australian aviation industry has been a part of the national fabric for many years, safely serving the people in rural and regional Australia, as well as those who live in the cities, safely in their times of need.

February 2020 marks the first anniversary of the Far North and North Queensland monsoonal floods, which caused devastation to cattle farmers across rural and regional Queensland.

“Aerial musterers play a vital role in the day to day operations of cattle stations across the top end of Australia,” Chief Commissioner Hood said. “During the floods last February in the northern parts of Queensland, a group of a dozen helicopter pilots from rural and regional Queensland safely supported farmers through this disaster for over a fortnight, even contributing to some of the costs from their own pockets. This is the true Australian spirit to help those in need during a time of crisis, and we are seeing this spirit reflected today.

“It is important to acknowledge the safe flying culture which is instilled in the Australian aviation industry. While the bushfire season is far from over, I would like to remind all pilots to continue to fly within the limits of their aircraft and themselves.”

ATSB releases C-130 large air tanker accident preliminary report.

The Australian Transport Safety Bureau has released the preliminary report from its ongoing investigation into the collision with terrain of a Lockheed C-130 large air tanker during aerial firefighting operations north-east of Cooma, NSW on 23 January 2020, in which three aircrew were fatally injured.

The preliminary report details basic factual information established in the investigation’s early evidence collection phase, including the accident’s sequence of events, wreckage and impact information, and weather details. The preliminary report also confirms that ATSB data recovery analysts were able to successfully download the C-130’s cockpit voice recorder (CVR).

“Although the recorder assembly was damaged in the accident, ATSB investigators were able to successfully recover all the data from the CVR’s crash protected memory module,” said ATSB Chief Commissioner Greg Hood.

“However, unfortunately the CVR had not recorded any audio from the accident flight. Instead, all recovered audio was from a previous flight when the aircraft was operating in the United States.”

The aircraft had been in Australia since November 2019, and why the CVR did not record the accident flight will be considered as part of the ongoing investigation.

“Audio from cockpit voice recorders often play an important role in aircraft accident investigations, however, our investigators do have a range of other evidence, including witness videos, at their disposal in building a comprehensive understanding of the accident sequence,” Chief Commissioner Hood said.

As the investigation continues, the ATSB will complete its teardown and inspection of the aircraft’s engines and propellers; review the aircraft’s maintenance history, and performance and handling characteristics; analyse witness reports; and develop a more comprehensive understanding of the accident impact sequence with the use of 3D drone mapping and video analysis of witness videos.

“The ATSB’s on-site examination of the wreckage, damage to the surrounding vegetation, and ground markings indicated that the aircraft initially impacted a tree in a left wing down attitude, before colliding with the ground,” Mr Hood said.

The investigation will also consider environmental influences; the crew’s qualifications, experience and medical information; the nature of aerial fire-fighting operations; and operating policies and procedures.

“ATSB preliminary reports do not contain findings, identify contributing factors or outline safety issues and actions, which will be detailed in an investigation’s final and any interim reports,” Mr Hood said.

“An investigation of this nature and complexity may take more than 18 months to complete.

“However, should any safety critical information be discovered at any time during the investigation, we will immediately notify operators and regulators, and make that publicly known.”

Mr Hood again extended his sympathies to those affected by this accident.

“On behalf of the ATSB, I convey our sympathies to the families and friends of the three aircrew who lost their lives in this accident in the service of others,” Mr Hood said.

“The ATSB would also like to acknowledge the support of the NSW Police Force, the NSW Rural Fire Service, NSW Fire and Rescue, the Australian Defence Force in facilitating safe access to an active fire ground and supporting our on-site investigation team. We also acknowledge and thank the warm-hearted support of the communities of Peak View and Cooma during the ATSB’s extensive on-site deployment.”

Read the preliminary report: Collision with terrain involving Lockheed EC130Q, N134CG, 50 km north-east of Cooma-Snowy Mountains Airport (near Peak View), New South Wales, on 23 January 2020

Ongoing investigation to examine engines, records and flight review requirements.

One of an Angel Aircraft Corporation Model 44 aircraft’s two engines was heard to ‘splutter’ soon after take-off from Mareeba Airport, Queensland, shortly before the aircraft collided with terrain, fatally injuring the two pilots on board, an ATSB investigation’s preliminary report into the 14 December 2019 accident notes.

The aircraft had been conducting a flight review — a regular assessment flight undertaken by all qualified pilots — with a Grade 1 flight instructor seated in the right seat and the owner pilot of the aircraft seated in the left seat.

The aircraft had commenced its initial take-off run just before 11.00am, with witnesses reporting that it sounded like one of the engines was hesitating or misfiring during the take-off roll, and with black sooty smoke seen trailing from the right engine.

Once airborne, the aircraft headed for the airfield’s training area. After eight minutes in the training area, the pilot seated on the left broadcast they were inbound to Mareeba and two minutes later broadcast that they were joining crosswind for runway 28. No further transmissions were heard from the aircraft.

An engine was then heard to splutter as the aircraft climbed to between 300 and 450 feet.

Witnesses reported seeing the aircraft touch down on the runway and take off again. An engine was then heard to splutter as the aircraft climbed to between 300 and 450 feet above ground level. The aircraft was next seen above a banana plantation beyond the end of the runway in a right descending turn, before it suddenly rolled right. Witnesses saw the right wing drop to near vertical and the aircraft collided with terrain in a cornfield.

Subsequent examination of the wreckage by ATSB transport safety investigators indicated the aircraft impacted terrain right wingtip first, followed by the nose, and left wingtip. The aircraft then pivoted about the left wing with the fuselage coming to a rest upright.

“The ATSB’s ongoing investigation will focus on further examination of the recovered engines and propellers, maintenance and operational records, aircraft and site survey data, pilot qualifications, experience and medical history, and regulatory requirements for flight reviews,” Dr Stuart Godley, ATSB Director Transport Safety, said.

Dr Godley noted that preliminary reports outline basic factual information established in the early phase of an investigation.

“Preliminary reports do not contain findings, identify contributing factors or outline safety issues and actions,” Dr Godley said. “These will be detailed in an investigation’s final report.”

Read the preliminary report: Loss of control and collision with terrain involving Angel Aircraft Corporation 44, VH-IAZ, near Mareeba Airport, Queensland, on 14 December 2019

ATSB preliminary report details loss of separation incident

The design of standard instrument approaches and departures, air traffic control and flight crew actions and procedures, and the coding of aircraft flight management system navigation databases are among a number of the factors the ATSB is focusing on as part of the on-going investigation into a loss of separation event near Sydney Airport.

That investigation’s preliminary report, released on 16 January, details that separation between two Qantas aircraft, an Airbus A330-300 and a Boeing 737-800, was reduced to about 0.43 nautical miles (796 metres) laterally and about 500 feet (152 metres) vertically during the incident, which occurred at around 6:30pm on 5 August 2019.

The A330 had been cleared by air traffic control to take-off from Sydney Airport’s runway 34 Right, at the same time that the 737 was on final approach to land on the same runway.

While the A330 was commencing its takeoff run, the air traffic controller with responsibility for managing runway 34 Right, an otherwise experienced controller who was a trainee under supervision for the Aerodrome Controller – East (ADC-E) position, assessed that if the 737 continued to land, there would be insufficient runway spacing between the two aircraft, and so instructed the 737 to conduct a go around.

The preliminary report details that the loss of separation occurred as both aircraft turned to the right.

The preliminary report details that the loss of separation occurred as both aircraft turned to the right, with the A330 turning to the right following a standard instrument departure (SID) from runway 34R (the MARUB 6 SID) and the 737 turning to the right following the missed approach procedure for a GLS (a global navigation satellite system landing system) approach for a landing on runway 34R.

The ADC-E controller, who reported that he had both aircraft in sight, attempted to increase their separation by instructing the 737 to turn further right. As both aircraft converged, the A330 flight crew received a traffic advisory (TA) alert from their aircraft’s airborne collision avoidance system (ACAS).

The A330 first officer, who was pilot flying, then saw the 737 in close proximity and, in response, reduced the aircraft’s angle of bank to reduce the turn towards the 737.

The captain of the A330 radioed to advise the ADC-E controller that their proximity to the 737 was “very close”. The controller then issued an instruction to the A330 flight crew to turn left.

The A330 climbed to 5,000 feet and continued to Melbourne without further incident. The 737 climbed to 3,000 feet and was issued radar vectors for a second approach to runway 34R. It landed without further incident a short time later.

“Preliminary reports outline basic factual information established in the early phase of an investigation. They do not contain findings, identify contributing factors or outline safety issues and actions, which will be detailed in an investigation’s final report,” explained ATSB Director Transport Safety Dr Stuart Godley.

“The ATSB’s on-going investigation into this occurrence will focus on a range of factors including the design and risk assessment of MARUB standard instrument departures and missed approaches from Sydney Airport’s runway 34 Right; air traffic control procedures, controller training and controller actions; flight crew actions and the operator’s procedures for the 737 and A330; coding of flight management system navigation databases; and further analysis of flight data recordings and ATC recordings.”

Read the preliminary report: Close proximity involving Boeing 737, VH-VZO and Airbus A330, VH-EBJ, at Sydney Airport, New South Wales, on 5 August 2019

Operate amateur-built helicopters within design intent.

The fatal in-flight break-up of a Cicaré CH-7 helicopter highlights the importance of operating amateur-built helicopters within their design intent to avoid unintended stresses, and ensuring that any modifications are assessed for the effects on structural integrity and handling.  

On 28 July 2015, the pilot/owner of an amateur-built (kit-assembled) Cicaré CH-7BT helicopter, registration VH-JEW, departed Indee Station in Western Australia for Roy Hill Station for planned aerial mustering work the next day. When about 8.5 NM north-west of Roy Hill Station, the helicopter’s stabiliser assembly fractured and separated from the tail boom, leading to the separation of the mast and main rotor. The helicopter then collided with terrain, fatally injuring the pilot.

During the subsequent ATSB investigation, examination of the recovered components found that the stabiliser mount had fractured due to overstress following the propagation of a fatigue crack in the area adjacent the weld. The crack had likely to have been present for some time prior to the final fracture.

While the ATSB was unable to fully determine the reasons for the initiation and propagation of the fatigue crack, it was likely the result of some combination of the design, operating conditions, and untested accessories. The helicopter had been fitted with an external storage pod, likely without the appropriate engineering assessment to ensure that the pod would not have an adverse effect on the helicopter’s performance, handling and structure.

The ATSB also found that, although the CH-7B was intended for recreational use only, this and other CH-7B helicopters had been used for aerial mustering. Operating outside the manufacturer’s design intent had the potential to induce stresses on the aircraft, leading to premature wear of components and possible failure.

“Aerial mustering can involve extremely frequent manoeuvring and rapid power changes that can apply very high loads on a helicopter that may be quite different to the type of flying for which it was designed,” ATSB Director Transport Safety Dr Stuart Godley said.

“The ATSB is advising the Australian agricultural mustering community that the manufacturer, Cicaré S.A., has stated these helicopters are not intended or recommended for aerial work, particularly mustering operations.”

“The ATSB is also advising owners and operators of amateur-built helicopters that, operating within their stated design intent and limitations is essential for safe flight. This also includes the addition of unapproved modifications or external accessories.”

Dr Godley noted that mustering operations and the addition of unapproved modifications, outside the limitations prescribed by the manufacturer, can potentially produce unintended stresses on the airframe leading to the premature failure of components.

“A Safety Advisory Notice is currently being distributed to Cicaré helicopter owners highlighting the risks associated with operating amateur-built helicopters outside of their design intent.” 

Safety Advisory Notice AO-2015-089-SAN-014: Are you operating your amateur-built helicopter as designed?

Read the final report: In-flight break-up involving Cicaré S.A. CH-7BT helicopter, VH-JEW, near Roy Hill Station, Western Australia, on 28 July 2015