Primary finding
Probable cause
The pilot’s decision to conduct a prolonged slip against warnings specified in the Pilot’s Operating Handbook which resulted in a total loss of engine power due to fuel starvation.
Investigator assessment
Analysis narrative
The pilot reported that while about 3,000 ft mean sea level (msl), he slipped the airplane to descend 1,100 ft to get to the traffic pattern altitude. After leveling off, he saw the fuel pressure drop. He checked to make sure that both fuel pumps were on. Shortly after, the airplane lost all fuel pressure and engine RPM. After troubleshooting, he was unable to restore engine power, and initiated a forced landing to a golf course, where the airplane impacted trees and sustained substantial damage to the fuselage, empennage, and wings. The Pilot’s Operating Handbook for the airplane, stated in part “the fuel lift pipe in the fuel tank is situated adjacent to the lower inside wall of the tank. The aircraft should at no time be subjected to a sustained side slip towards a near empty fuel tank (i.e. -right wing down) as, despite the baffling, this may have the consequence that the fuel runs towards the outer edge of the tank exposing the fuel pipe to suck air, thereby starving the engine of fuel leading to engine failure. This poses a particular threat when at low altitude, typically prior to landing.” The pilot did not initially report that there was no mechanical malfunction or failure that would have precluded normal operation; however, upon reviewing the recorded flight data with his chief flight instructor, that included the bank angle indicator, slip/skid indicator, and fuel pressure, the pilot concluded that the loss of power was likely from the left fuel lift pipe becoming exposed, starving the engine of fuel.