A loss of control during asymmetric flight most likely led to the fatal crash of a Cessna 310 near Mildura, according to an Australian Transport Safety Bureau (ATSB) report released yesterday.
VH-BWZ was on final approach to Mildura on 6 November 2015 when it crashed. Witnesses saw the aircraft yaw left before the left wing dropped and the aircraft rapidly lost altitude. The resulting impact with the ground destroyed the aircraft and fatally injured the pilot.
ATSB investigators found that several factors contributed to the likely loss of control.
"The aircraft's left engine was found to have been starved of fuel and at the time of the accident was not producing power," the report states. "The left propellor was found to be toward fine pitch, not feathered, and the flaps and landing gear were fully extended, consistent with a normal landing configuration.
"In that configuration, with the engine not producing power, the aircraft's performance would have degraded to the extent that the altitude could not be maintained."
Investigation revealed the aircraft should have had plenty of fuel on board, but that none was recovered from the fuel manifold or supply lines for the left engine. Investigators also found the fuel selector for the left engine was positioned between the left auxilliary tank and the cross-feed, but it couldn't be determined if the the pilot selected it that way or if the position was the result of the impact.
Consequently, the ATSB was unable to determine why the left engine was starved of fuel.
The ATSB also noted that with one engine out, a Cessna 310 has a single-engine climb-out rate of 375 feet per minute at sea level and maximum landing weight, but with the gear down and flaps extended, the performance degrades to an 875 feet per minute rate of descent.
"This accident has emphasised the adverse consequences of aircraft configuration on performance with one engine inoperative, particularly when at low altitudes," the reports states. "It reinforced the importance of pilots remaining well versed in engine failure response procedures and being aware of the drag penalties associated with varying conditions."
The full investigation report is on the ATSB website.