The fatal crash of a Dynaero at Serpentine in 2020 was caused when the aircraft stalled as the pilot attempted to return to the airport after a low-level power loss, according to an ATSB report released this week.
Dynaero VH-SIP was being prepared for a ferry flight from Serpentine south of Perth to Queensland, when the aircraft experienced a partial power failure at 300 feet after taking off from runway 09. The pilot attempted to make a left turn for a landing on runway 23, but the aircraft stalled in a tight turn at only 150 feet AGL.
The ATSB report attributes the power failure to inadequate maintenance done to return the aircraft to service after five years of not being flown.
VH-SIP had recently been bought by a new owner, but the owner had to return to Queensland before the maintenance was completed, resulting in the accdient pilot volunteering to do the ferry once the aircraft was ready.
The power problem had been detected before the accident flight, and a LAME was working on the aircraft to troubleshoot the problem. The LAME said he expected the pilot would conduct a high-speed ground run on runway 09.
ATSB Director Transport Safety Dr Stuart Godley said the crash highlighted the risk of trying to return to the airport after a partial engine failure after take-off (EFATO).
“Partial engine power loss is a more frequent, and a more complex occurrence than complete engine power loss,” he said.
“The ATSB encourages pilots to review the recommended partial power loss procedure in their aircraft’s pilot operating handbook, and cautions against attempting to turn back towards the runway under reduced power unless in controlled situations where sufficient altitude exists."
During the investigation, the ATSB found that the left carburettor was missing a components and contained significant contamination, and several maintenance tasks required to return the aircraft to service had not done adequately.
Investigators believe this led to over-fueling in the left carburettor, which caused rough running and power loss.
The report also points out that the ferry pilot, an ATPL with 6000 hours, had never flown a Dynaero or any Rotax-powered aircraft before.
The full report is on the ATSB website.