Cessna 177B N35170 accident near London, Ohio

Probable cause

The flight instructor's inadequate in-flight fuel management, which resulted in a total loss of engine power due to fuel exhaustion.

NTSB analysis

The flight instructor and the student pilot were in a cruise descent toward the destination airport when the engine experienced a total loss of power. The instructor performed a forced landing to a corn field, during which the airplane sustained substantial damage. The instructor reported that the airplane had 25 gallons of fuel onboard before takeoff and that the duration of the accident flight was 1.3 hours. Due to a recent engine overhaul, the instructor was operating the airplane at a high power setting with the mixture full rich. He noted that, during previous flights, the fuel consumption was about 11 gallons per hour and calculated that the airplane should have burned about 14.3 gallons of fuel during the accident flight. Since the engine was not being operated at normal cruise power settings, fuel burn based on information in the pilot's operating handbook could not be calculated; however, examination of the airplane after the accident revealed no usable fuel remaining in either wing fuel tank, and no breaches of the fuel system. Subsequent testing revealed no fuel leakage and no excessive fuel consumption during ground runs.

Based on the available evidence, it is likely that the engine lost power due to fuel exhaustion; however, whether the pilot overestimated the fuel quantity before departure or underestimated the fuel consumption during the flight could not be determined.

Text from the NTSB. Open the NTSB docket for CEN17LA358 for the full record.