What happened
At an altitude of 9,500 feet, the aircraft's engine failed while the pilot was maneuvering to land on a rural road situated within heavily forested mountains. During this critical phase of flight, the aircraft lost control and impacted a large tree.
The investigation
A mechanical examination of the recovered engine revealed significant internal damage. The top of the engine case contained a large hole located on the rear portion. Additionally, pushrod housings were missing from cylinders #5 and #6. The rear case was filled with massive amounts of metal debris. Examination showed that the major portion of the connecting rod for cylinder #5 was missing.
Findings
The investigation determined that fuel exhaustion or mechanical failure led to the loss of power. The presence of a large hole in the case top and missing pushrod housings indicates severe internal engine disintegration. The absence of the major portion of the connecting rod for cylinder #5 suggests a catastrophic mechanical breakdown. These factors contributed to the inability to maintain flight, resulting in the impact with the tree.
Safety message
Pilots should monitor engine parameters closely and be prepared for immediate action in case of sudden power loss, especially when operating in mountainous terrain where alternative landing sites are limited.