A pilot likely drank a significant amount of alcohol the night before he died in a light aircraft crash south of Perth, the transport safety bureau has found.
The single-engine Dynaero MCR-01 plane took off from Serpentine Airfield on the afternoon of December 28, 2020, for a post-maintenance check flight.
When the plane reached about 90 metres above ground level, the engine began to run rough.
The pilot started to turn left, but the aircraft appeared to decelerate, before it stalled and crashed into the ground.
The pilot, who was the sole occupant, died in the crash and the aircraft was destroyed.
The Australian Transport Safety Bureau on Thursday released its final report into the incident, finding multiple tasks in the aircraft's return to service were not adequately carried out.
The engine's left carburettor was missing a component and contained a significant amount of contamination, the report stated.
The pilot was also unfamiliar with the aircraft and engine type, which increased his risk of not being able to adequately manage an in-flight emergency.
The safety bureau also found the pilot had probably consumed a "significant amount" of alcohol the night before the incident, which increased his risk of post-alcohol impairment.
A number of airfield members had met for an informal social dinner the previous night, with witnesses saying the pilot engaged in "fairly heavy" drinking and appeared "really drunk".
The function ended about 1.30am on the day of the accident and a witness reported the pilot was "not significantly impaired by alcohol" when he last saw him at 1.47am.
A post-mortem report also found there were no levels of alcohol detected in the pilot's blood or urine samples.
The safety bureau noted the pilot waited more than the required eight hours to fly the aircraft after drinking.
But post-alcohol impairment could increase the potential for spatial disorientation for up to 48 hours, the report stated.
"While a pilot may be legally able to fly eight hours after drinking, the residual effects of alcohol may seriously impair their performance when they need it most, such as during an emergency," the report said.
Australian Associated Press
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