Incident Overview
During cruise flight at 12,500 feet, the pilot observed a sudden drop in manifold pressure from 51.8 inches to 25 inches. The engine exhibited poor response to throttle movements, and the pilot described the engine sounding abnormal when the throttle was adjusted. Concerned about the remote terrain below, the pilot decided not to continue the flight and began consulting maps to identify the nearest suitable airport. As he did so, the aircraft began losing altitude. The pilot noted that the engine did not seem to produce sufficient power, and by the time he was approximately 3,000 feet above ground level (AGL), he initiated a forced landing onto a dirt road.
Accident Sequence
During the landing rollout, the aircraft struck poles located alongside a cattle guard. No further details about the aircraft's condition or the strike are provided in the source.
Post-Accident Examination
According to the salvage company and the Federal Aviation Administration (FAA) inspector who examined the engine, two of the four screws securing the rocker cover on the number 3 cylinder were missing, and oil was leaking from that area. The rocker cover displayed a round indentation on its exterior surface and a wear mark on the interior. Additionally, the exhaust rocker arm studs were found to be loose. The rear stud was only finger tight, with aluminum material embedded in its threads. The front stud was also loose, but its nut locking mechanism remained intact.
Observations
The source does not specify the aircraft type, registration, date, operator, location, number of occupants, injuries, or extent of damage. No details regarding time of day, weather, or air traffic control involvement are provided.