On February 16, 2005, a Mooney M20K (registration N1147D) operated by Albert G. Satterla was involved in an aviation accident near Roseburg, OR. Investigators recorded the probable cause as: A fractured piston pin that resulted in a loss of engine power and subsequent forced landing. Factors include rough/uneven mountainous terrain. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
Shortly after takeoff, the engine lost manifold pressure and RPM, accompanied by oil pressure loss. The pilot performed an off-airport landing in a wooded area. Post-accident examination revealed a fractured piston pin and metallic debris restricting oil flow.
Accident Sequence
During the initial climb after takeoff, the pilot observed a loss of manifold pressure and engine RPM. Concurrently, oil pressure decreased. The pilot elected to land the airplane off-airport, touching down in a wooded area.
Post-Accident Examination
Examination of the engine revealed a fracture at the distal end of the number 5 piston pin. The inner aluminum piston pin insert had fractured just inboard of where the pin tapers outward. The fracture face was flat and perpendicular to the outer surface of the steel housing. Both fracture surfaces sustained extensive smearing damage and metal loss, precluding a detailed fracture analysis.
Heavy scoring was found on the wall of the number 5 cylinder assembly and piston. Extensive mechanical damage was observed in the relief area of the piston. The bottom piston ring was seized. Inspection of the oil sump showed it contained oil along with a large amount of metallic particles. The oil pickup tube and screen were intact and also contained significant metallic particles similar to those in the sump. The quantity of metallic particles in the pickup tube and screen was sufficient to restrict the oil flow passage. The metallic particles were non-magnetic.