Update: 10 July 2020
This update details factual information established in the investigation’s early evidence collection phase, and has been prepared to provide timely information to the industry and public. It contains no analysis or findings, which will be detailed in the investigation’s final report. The information contained in this update is released in accordance with section 25 of the Transport Safety Investigation Act 2003.
Update: 10 July 2020
Based on closed-circuit television (CCTV) footage and an examination of the wreckage, the ATSB investigation into the fatal R44 helicopter accident near Broome Airport on 4 July 2020 has determined that the helicopter experienced an in-flight breakup. The tail rotor gearbox assembly, tail rotor and empennage assembly separated soon after the helicopter lifted off. The fuselage then fell to the ground out of control.
The ATSB has conducted a detailed examination of the entire aircraft at Broome, and is transporting relevant components back to Canberra for more detailed examination. These components include the tail rotor gearbox, tail rotor, empennage, tail cone, tail rotor drive shaft, and flight controls. During this process, the ATSB has been consulting with the Robinson Helicopter Company (the helicopter manufacturer), the US National Transportation Safety Board and the Australian Civil Aviation Safety Authority.
Images of the components that separated are provided at the end of this update. The ATSB will not be releasing the CCTV footage due to its potentially distressing nature. The ATSB is providing access to the footage to relevant experts to assist with the investigation.
The ATSB has interviewed a pilot who recently flew the helicopter and maintenance personnel who conducted maintenance on the helicopter. It has also obtained copies of the helicopter’s maintenance records and reviewed other documentation. Based on this information:
- The R44 Raven I helicopter involved in the accident (serial number 2544) was manufactured in 2018. It was imported new into Australia and was first registered on the Australian civil aircraft register in August 2018.
- The helicopter underwent its last periodic (100 hourly) inspection on 4 June 2020, with 286.9 hours total time in service.
- A pilot who flew the helicopter on 2 July 2020 to Broome Airport reported feeling unusual vibrations through the tail rotor pedals. He described it as if something was repetitively tapping through the pedals. The pilot of the accident flight also conducted a short flight in the helicopter and confirmed the unusual vibrations.
- Maintenance personnel conducted a dynamic tail rotor balance on 3 July 2020 (the day before the accident). The dynamic tail rotor balance was found to be within limits, and the maintenance personnel could not detect any unusual vibration on the ground.
- The accident flight was the first flight since the maintenance was conducted. Overall, the helicopter had 291 recorded hours in service.
- The Robinson R44 was certified in December 1992 and the R44 Raven I was introduced in January 2000. There are currently 558 R44s on the Australian civil aircraft register.
In the initial phase of its investigation, the ATSB is focussed on examining the wreckage, reviewing the CCTV footage and reviewing potentially related occurrences.
At this stage the reasons for the in-flight breakup are not known. The ATSB will provide further advice when relevant information is available.
Pilot advisory information
The R44 Pilot’s Operating Handbook (POH) includes the following 'safety tip':
A change in the sound or vibration of the helicopter may indicate an impending failure of a critical component. If unusual sound or vibration begins in flight, make a safe landing and have the aircraft thoroughly inspected before flight is resumed. Hover helicopter close to the ground to verify problem is resolved, and then have aircraft reinspected before resuming free flight.
The ATSB strongly endorses this advice, and urges any R44 pilot that experiences unusual vibrations through the tail rotor pedals to land as soon as possible and follow the advice in the POH safety tip.
Images of the separated components
The following images show the empennage (Figure 1), the tail rotor gearbox (Figure 2), the tail cone (Figure 3), and the tail rotor (Figure 4).
The ATSB is investigating a collision with terrain involving a Robinson R44 helicopter, registered VH-NBY, near Broome Airport, Western Australia, on 4 July 2020.
The helicopter was departing from Bilingurr, about 2 km north of Broome Airport, with the pilot and three passengers on board. Soon after lifting off, the helicopter collided with terrain. The pilot and one passenger were fatally injured and the other two passengers were seriously injured.
Transport safety investigators with experience in helicopter operations, helicopter maintenance and aircraft systems from the ATSB’s Perth and Brisbane offices will examine the wreckage and the accident site.
The ATSB will also analyse any available recorded data and interview witnesses. In addition, the ATSB will review aircraft maintenance and operational records, pilot records and weather information.
A preliminary report will be released within about 30 days of the accident. A final report will be published at the conclusion of the investigation.
Should any safety critical information be discovered at any time during the investigation, the ATSB will immediately notify operators and regulators so appropriate and timely safety action can be taken.
|Date:||04 July 2020||Investigation status:||Active|
|Time:||14:36 WST||Investigation level:||Defined - click for an explanation of investigation levels|
|Location:||2 km north Broome Airport||Investigation phase:||Evidence collection|
|State:||Western Australia||Occurrence type:||In-flight break-up|
|Release date:||10 July 2020||Occurrence category:||Accident|
|Report status:||Pending||Highest injury level:||Fatal|
|Anticipated completion:||3rd Quarter 2021|
|Aircraft manufacturer||Robinson Helicopter Co|
|Type of operation||General Aviation|
|Damage to aircraft||Destroyed|
|Departure point||Near Broome, Western Australia|