Cessna 150M N6266K accident near Woodland, Washington

Probable cause

The flight instructor’s inadequate preflight planning, which resulted in fuel exhaustion and a total loss of engine power.

NTSB analysis

The student pilot used a fuel dipstick ruler to measure the quantity of fuel in each wing tank and reported 13 and 9 gallons, respectively, during the preflight. Shortly after, the student and the flight instructor departed the local airport to practice steep turns and slow-flight maneuvers, including an introduction to power-off stalls and recovery. About an hour into the flight, during a stall maneuver recovery (with carburetor heat on), the instructor increased the throttle setting but the engine remained at idle. As the power remained unchanged, the instructor decided to execute an off-airport landing to a nearby field. Shortly after touchdown, the landing gear separated and the airplane nosed over, resulting in substantial damage to the aft fuselage.

Postaccident examination of the airframe and engine did not reveal any mechanical anomalies. Flight control and valvetrain continuity were established. No fuel was recovered at the accident site. The fuel system was traced from each wing tank to the carburetor at the engine through the fuel selector, which rotated normally and was unobstructed. The fuel filter bowl remained secured to its mount and had about 2 oz of fuel consistent with 100LL avgas.

Although weather conditions were conducive to serious carburetor icing at cruise power, the flight instructor reported that carburetor heat was applied during the stall maneuvers. The operator reported that the airplane was not refueled after the previous flight or before the accident flight. Based on the engine time that accrued since the last fueling, and the minimal amount of fuel found in the airplane after the accident, the student pilot’s fuel reading was likely incorrect and did not accurately account for the amount of fuel available for the flight.

As a result of the accident, the operator updated their procedures requiring all flight instructors to verify and sign off on the reported fuel level after each student preflight.

Text from the NTSB. Open the NTSB docket for WPR24LA039 for the full record.