Incident Overview
While in cruise flight, the pilot noticed an unusual smell, suspected to be electrical or smoke. Shortly thereafter, the engine oil pressure decreased. The powerplant then started to vibrate, prompting the pilot to shut it off. The pilot was communicating with air traffic control and attempting a precautionary landing at an airport when the forced landing occurred.
Forced Landing
The airplane was landed in an open field approximately one mile from the end of the runway that the pilot had been cleared to land on. During the landing roll on unsuitable terrain, the airplane flipped over.
Post-Accident Examination
Post-accident examination revealed that an O-ring in the oil filter adaptor assembly was crushed, and the engine oil escaped at that damaged area, causing the loss of power. No oil remained in the engine. The adaptor assembly had been worked on the day before the flight by other maintenance personnel.