A tiny camera could hold clues to what happened when a pilot was seriously injured during an air show manoeuvre gone wrong.
In a preliminary report into the crash released on Wednesday, the Australian Transport Safety Bureau said video footage of the accident from an onboard GoPro camera was aiding its investigation.
The single-seat Pitts S1‑11X aircraft was performing a series of daring loops and aerobatic tricks known as a "triple avalanche" alongside three other planes at the Australian International Airshow at Avalon Airport in Melbourne in March when it crashed.
The plane crashed west of the runway, opposite public viewing areas and grandstands, creating a 95m ground scar and debris trail before coming to rest upright.
It hit a grassy area where multiple live pyrotechnics had been set up to be detonated later as part of the show.
The pilot, part of the Sky Aces display team, was seriously injured but was provided first aid before being transported by helicopter to hospital.
Pyrotechnicians working nearby were the first to arrive at the wreckage, helping the pilot out of the aircraft despite difficulties opening the cockpit canopy.
First responders reported smelling fuel and observing it leaking from the aircraft, the bureau said.
Investigators later transported the aircraft wreckage to a secure hangar at the airport and found "no evidence of any control or airframe issues before the accident".
Airframe refers to the mechanical structure of the plane.
Evidence gathered as part of the investigation included footage from a forward‑facing GoPro camera from the cockpit that showed the pilot was unable to stop the rapid rate of descent before the plane hit the ground.
It also showed he had started performing the loops some 30 metres above ground, reaching a peak height of 210-250m, where he started his "snap rolls".
The report said the pilot began the aerobatic manoeuvres at a higher altitude in previous training flights.
Photos from the preliminary report show the orange aircraft substantially mangled.
Glen Collins, an experienced pilot from stunt flight company Paul Bennet Airshows, said he sustained spinal damage in the accident and would require multiple surgeries.
A fundraiser has been set up to help cover Mr Collins' medical expenses.
