What happened
The pilot was operating the aircraft while cruising at an altitude of approximately 850 feet above ground level. During this phase of flight, the sound emanating from the engine changed pitch, accompanied by an observed decrease in revolutions per minute of roughly 100 RPM. Believing that the engine throttle had inadvertently moved back toward the idle position, the pilot advanced the throttle to restore power.
Immediately following this adjustment, the engine suddenly stopped running and seized completely. The loss of power necessitated an off-airport forced landing. During the landing sequence, the airplane nosed over, resulting in substantial damage to the airframe.
The investigation
An examination was conducted to determine the root cause of the mechanical failure. However, the specific reason for the sudden power loss and subsequent engine seizure could not be definitively determined by the investigators.