What happened
While performing a landing approach at 200 feet and 1/2 mile from the runway end, the engine of a Cessna (type not specified) failed. The certified flight instructor (CFI) assumed control of the aircraft, attempted to switch fuel tanks, and tried an engine restart, but was unsuccessful. During the emergency, the CFI raised the flaps and landing gear. The aircraft subsequently collided with trees and the ground.
The investigation
The investigation focused on the fuel system and engine operation. Both the pilot receiving instruction and the CFI could not recall which fuel tank was selected at the start of the flight. Post-accident examination showed the right wing had detached at the wing root. While the right fuel tank was not ruptured and no fuel was found on the ground, 5 gallons were recovered from the wing. The pilots estimated they departed with 26 gallons in each tank, though the aircraft manual indicates a capacity of 30 gallons per tank.
The left fuel tank showed no ruptures or leaks, and no fuel was found in the tank or on the ground. The landing gear remained in the down position. All engine controls, including throttle, mixture, and propeller linkages, were found to be intact and operable. Testing revealed that both the left and right fuel tanks were filled with water. Despite this, the engine was able to start and develop power when connected to an external fuel source using the selector valve in both positions.