Incident Overview
During cruise flight, the pilot-in-command encountered a complete mechanical stoppage of the powerplant. This necessitated an immediate forced landing.
Forced Landing
The pilot was forced to land in a burned section of woodland. The area contained dead trees scattered throughout and was characterized by rough and uneven tundra terrain.
Engine Examination
Subsequent examination of the engine revealed that the number 5 cylinder's piston wristpin had failed. This failure allowed the connecting rod to separate from the piston. The connecting rod then impacted the internal portions of the engine case within its plane of rotation, jamming into the case and causing the engine to cease rotation.
Probable Cause
The probable cause of the engine stoppage was the failure of the number 5 cylinder's piston wristpin, leading to connecting rod separation and subsequent internal engine case damage.