Engine failure may have contributed to the fatal crash that claimed the lives of three Advantage Aviation pilots near the Provo Airport.
The National Transportation Safety Board, which conducts accident investigations, has made a preliminary report on the April 17 accident. The report found that the rudder trim on the plane was deflected to the right and a trim on the left aileron was set to full tab up.
“That indicates that they made the turn from downwind to final at too steep a turn,” said Mike Burton, chief flight instructor at Advantage Aviation. “A control tower would have cleared the traffic and allowed the pilots to make a straight-in landing.”
Burton also said the pilots themselves were probably too close to the runway on downwind, and they turned at a considerably steeper angle than is normal for that aircraft.
“They needed a wider and longer turn to make a safe landing,” Burton said.
Rich Crandall, UVSC Flight School director, said he believes there was an engine failure.
“Until the accident investigation is complete, we won’t know exactly what caused the accident,” Crandall said. “The preliminary report indicates that they had full rudder trim, which indicates there might have been an engine failure”.
Advantage Aviation said it is hard to tell whether or not there was an engine failure.
“People on the ground heard engines running at full RPM (revolutions per minute),” Burton said.
Burton conceded, however, it would be difficult to tell if one or two engines were running on a multi-engine aircraft like the Cessna 310D.
“The engines running at full RPM might indicate that the propellers had not been feathered,” Burton said. “If one engine were dead, it could still appear to be running according to those on the ground.”
When a propeller is feathered, the propeller is aligned with the wind flow to create less drag and does not require the engine to turn it.
“When you have a twin engine airplane and you have engine failure, you are going to put in full rudder trim to keep the engine from failing on you,” Crandall said.
A final NTSB report takes about 10 months to complete, Burton said. The engines have been impounded and sent back to the manufacturer for inspection. Airplane engines at Advantage Aviation are routinely disassembled and rebuilt after 1,700 flight hours.