Overview
During a training flight, a pilot and flight instructor were practicing stall maneuvers approximately 30 minutes after departure. The pilot reported that the engine lost power while executing a stall series. Attempts to regain full engine power were unsuccessful, prompting the flight instructor to take control and perform a forced landing into a corn field.
Flight Details
The pilot had completed a preflight inspection and noted that the airplane was topped off with aviation fuel. During the engine run-up, all systems operated normally and no engine problems were detected before takeoff. The loss of power occurred about half an hour into the flight during stall practice.
Post-Accident Examination
A post-accident examination of the airplane revealed a substantial amount of fuel present in the fuel system. However, no fuel was found in the fuel flow divider. The engine itself showed no mechanical deficiencies upon inspection. Additionally, the examination disclosed that a lawn mower battery had been installed in the airplane. According to the pilot, an annual inspection had been completed by the previous owner several days before the purchase of the aircraft.