Cessna 172M N12842 accident near Hilo, Hawaii

Probable cause

Water contamination in the fuel system due to the flight instructor’s and pilot receiving instruction’s failure to drain all the water from the system during the preflight inspection, which resulted in a loss of engine power.

NTSB analysis

The flight instructor and pilot receiving instruction reported that, during the preflight inspection before the local instructional flight, they drained water from the fuel tanks. After departure, they flew for about 1 hour and then returned to the airport to practice touch-and-go landings. During the approach for landing, the pilot receiving instruction accomplished a no-flap "slip to landing." After touchdown, he applied power for the takeoff, and the airplane then reached between about 75 and 100 ft above ground level, at which point the engine began to run irregularly, and subsequently, it lost power. The flight instructor took control of the airplane and executed a left turn away from buildings located at the end of the runway. Subsequently, the airplane impacted a grassy area northeast of the departure end of the runway.

During the postaccident examination of the airplane, water was found in the fuel sump strainer and the carburetor, which likely led to the loss of engine power. It is likely the flight instructor and pilot receiving instruction failed to ensure that all the water was drained from the tank during the preflight inspection.

Text from the NTSB. Open the NTSB docket for WPR15LA146 for the full record.