The tiny reason why chopper fell from sky in NQ crash
A missing piece of hardware has been determined as the cause of a tragic helicopter crash that killed a member of a well-known Queensland cattle family while mustering near Cloncurry.
The Australian Transport Safety Bureau investigation, released on Tuesday, found the helicopter piloted by 40-year-old Brent Action broke up in the sky and crashed during a mustering preparation flight in 2017.
The three-year investigation findings revealed that the Robinson R22 Beta II helicopter was missing a fastener in the bellcrank, which made the assembly disconnect mid-flight.
The machine had recently undergone a huge overhaul and Mr Acton's flight was the commercial flight since its 2200-hour service.
The report states it was likely the fastener's self-locking nut was either not reinstalled or it was inadequately torqued during the overhaul.
It was not clear which had occurred as the company, Cloncurry Air Maintenance, did not "record or track" all maintenance during the four-month overhaul.
ATSB director of transport safety Dr Stuart Godley said the separation of this bolt would have caused the main rotor to tilt back and hit the aircraft's tail cone, which was found severed at the crash site about 7km from where it took off.
Mr Acton, a member of the prominent Central Queensland Acton family, left behind two children and wife Shona.
He was an experienced pilot who had been working for Cloncurry Mustering Company since 2004.
The crash occurred on Mr Acton's third-consecutive day of flying in the area.
The charred helicopter wreckage was reduced to "ash, molten aluminium and fibreglass mat" from an intense fire when it crashed among termite mounds on August 2, 2017.
Initially it was believed the two-seater helicopter may have hit powerlines near the crash site, but the investigation found no evidence of this.
The report states Cloncurry Air Maintenance was overrun with work at the time of the helicopter's maintenance, which likely reduced the chief engineer's capacity to oversee maintenance.
At an interview, none of the staff could recall any specific details about the overhaul as it was a "busy period".
The company has taken on board multiple safety measures, including improving their maintenance practices and adopting helicopter manufacturer's checklists.
As a result of the incident., the Civil Aviation Safety Authority highlighted the need for independent inspections to be conducted and recorded with each adjustment made on the rotor of Robinson helicopters.
Originally published as The tiny reason why chopper fell from sky in NQ crash