The ATSB has released a preliminary report from its on-going investigation into a fatal accident involving a Robinson R44 helicopter at King River, in the Northern Territory’s West Arnhem Land.
The report notes the helicopter was one of three conducting crocodile egg collection, able to carry a crewmember (‘sling person’) attached to a 100 ft long line to access crocodile nests.
All three helicopters had departed a staging area at King River to start egg collection from nearby nests on the morning of 28 February 2022.
“Crewmembers of the other two helicopters became concerned when they had not heard any radio communications from the third helicopter,” ATSB Director Transport Safety Stuart Macleod said.
One of the pilots elected to return to the area the third helicopter was operating in, and found the wreckage at a paperbark swamp approximately 300 m from the staging area.
The sling person was found approximately 40 metres from the main wreckage, and was fatally injured. The pilot was seriously injured, and was airlifted to hospital.
“Preliminary analysis of the site by ATSB investigators indicated the accident sequence had occurred while the helicopter was travelling in a north-west direction, shortly after it left the staging area,” said Mr Macleod.
“Initial assessment indicated the engine had stopped prior to the helicopter colliding with the ground,” Mr Macleod continued.
There was no visible damage to the tail rotor blades and drive system and flight control continuity was established.
An examination of the engine and associated components found no defects likely to result in engine stoppage. The helicopter’s two fuel bladder tanks were intact despite breaches of the surrounding metal tanks, and there was no fire.
After initial assessment, the wreckage was removed from the site, and ATSB investigators drained about 250 ml of fuel from the main tank’s bladder.
It was possible fuel escaped into the creek that flowed beneath the wreckage as the fuel system was compromised in the accident, the report notes.
“This preliminary report details factual information established in the investigation’s early evidence collection phase, and as such does not detail analysis or findings, which will be outlined in the investigation’s final report,’ Mr Macleod said.
“As the investigation progresses, the ATSB will include review and examine of electronic components retrieved from the accident site.
“Fuel system components, refuelling practices and fuel quality will also be reviewed and examined, as well as relevant maintenance records, operational documentation and regulations.”
Survivability aspects of the accident will also be considered.
Read the report: AO-2022-009 Collision with terrain involving Robinson R44, VH-IDW King River, Northern Territory, on 28 February 2022