What happened
The pilot was operating the aircraft during cruise flight when a partial power loss occurred. To address the mechanical issue, the pilot initiated a precautionary landing. The touchdown took place on uneven terrain, which contributed to the aircraft coming to rest in an inverted position.
The investigation
A thorough examination of the engine was conducted following the accident. Inspectors identified a crack measuring between 2 and 3 inches located near the number one cylinder. The engine had accumulated approximately 1,778 hours of operation since its last overhaul in 1961, making it roughly 53 years old at the time of the event.
Findings
The mechanical failure was linked to the age and condition of the powerplant. A crack in the cylinder was the primary physical defect found. The aircraft was operating with an engine that had not been overhauled for several decades, which likely contributed to the structural failure.