Cessna 172 N3964L accident near Youngstown, Ohio

Probable cause

A loss of engine power for reasons that could not be determined based on available information, which resulted in a forced landing.

NTSB analysis

The pilot reported he departed with 7 gallons of automotive fuel in the right fuel tank and 5.8 gallons of automotive fuel gallons in the left fuel tank and that he checked the fuel levels with a sight gauge. The right fuel gauge indicated “one quarter of a tank” and the left fuel gauge indicated “slightly less than half a tank.” After the completion of the local flight, the pilot entered the downwind leg of the traffic pattern. At the midfield point, the pilot added 10° flaps and applied full carburetor heat. The engine then “stumbled and quit.” The pilot attempted to restart the engine to no avail. The pilot had the fuel tank selector in the BOTH position.

The pilot increased the flaps to 40° and executed a teardrop-style left turn to the runway. The airplane “floated long” and landed on airport property beyond the runway into trees, at stall speed. The airplane came to rest with the left wing pointing down toward the ground and the right wing toward the sky. The three occupants were able to egress from the airplane without further incident. The airplane sustained substantial damage to the left wing and fuselage.

Postaccident examination of the airplane found both fuel tanks intact, with no signs of a fuel leak on the airframe. About a quarter of a gallon of fuel was drained from the right fuel tank and about four gallons of fuel was drained from the left fuel tank. The fuel tank selector was found in the BOTH position. Airframe to engine control continuity was confirmed. An examination of the engine revealed no mechanical anomalies.

The reason for the loss of engine power could not be determined based on the available evidence.

A review of the meteorological conditions near the time of the accident, showed that the formation of carburetor icing was not likely for the usage of aviation gasoline. However, the airplane was modified to use automotive gasoline, which the pilot used to fill the airplane with prior to the flight. References have stated that carburetor icing will occur in less time and at higher ambient temperatures with automotive gasoline than with aviation gasoline. Based on the available evidence, it could not be determined what, if any role, carburetor icing may have played in the accident.

Text from the NTSB. Open the NTSB docket for CEN22LA098 for the full record.