Accident Overview
An airplane experienced a loss of engine power during flight, attributed to fuel exhaustion. The subsequent forced landing occurred in a riverbed, during which the aircraft collided with rocks.
Sequence of Events
Prior to departure, the pilot had refueled the airplane. The flight lasted approximately two hours before the engine lost power. The pilot then switched the fuel source from the left tank to the right tank, which temporarily restored engine operation. However, about ten minutes later, the engine suffered a complete loss of power.
Post-Accident Examination
A Federal Aviation Administration inspector examined the airplane at the accident site. Fuel recovery efforts found a residual amount of fuel in the right tank, while no fuel was present in the left tank. Additionally, the inspector noted that the right fuel cap O-ring was split, and there was heavy blue staining originating from the fuel cap area, extending aft in a pattern consistent with slipstream flow to the trailing edge of the wing.
Findings
The investigation identified fuel exhaustion as the cause of the engine power loss. The condition of the right fuel cap O-ring and the observed staining indicated a potential fuel leak from that cap.