What happened
The airplane encountered an unexpected loss of engine power while operating in cruise flight. As the situation developed, the pilot initiated a forced landing procedure. The aircraft ultimately collided with trees situated within tree-covered terrain during this emergency descent.
The investigation
Examination of the aircraft's fuel system revealed critical mechanical anomalies. Specifically, the fuel selector valve was found to bind when rotated, preventing smooth operation. Furthermore, inspection showed no indentations at the right, left, or off positions on the valve mechanism. These physical characteristics indicated that the fuel selector valve would remain wherever it was positioned after being moved, rather than returning to a neutral or specific detent point.
Findings
The primary factor contributing to the accident was the mechanical failure of the fuel system controls. The binding action of the fuel selector valve likely prevented proper fuel flow management, leading to fuel exhaustion or starvation during the critical phase of flight. This mechanical defect directly resulted in the loss of engine power and the subsequent collision with terrain.
Safety message
Regular inspection of fuel selector valves for binding or lack of detent feedback is essential for maintaining safe aircraft operation. Pilots should be aware that valves which do not provide tactile confirmation of position may lead to inadvertent fuel system mismanagement.