Cessna 182P N640AM accident near Corona, California

Probable cause

A loss of engine power shortly after takeoff for reasons that could not be determined because postaccident examination did not reveal any anomalies that would have precluded normal operation. Contributing to the accident was the pilot’s decision to take off with a known but unidentified airplane deficiency.

NTSB analysis

At the end of a 3-hour-long traffic-watch flight, the pilot began to return to the departure airport. As the airplane transitioned the airspace of an adjacent airport, the engine speed dropped to idle and surged twice. The pilot performed a precautionary landing at the adjacent airport. After an uneventful landing, the pilot performed an engine run-up and more troubleshooting steps and was unable to replicate the engine problem. The pilot then decided to depart for the home airport; however, shortly after departure, the engine speed variations began again, eventually resulting in a total loss of engine power. The pilot performed a forced landing in a nearby field, where the majority of the airplane, including most of its fuel supply system, was consumed by postimpact fire. The engine sustained minimal damage, however, and postaccident examination revealed no evidence of preaccident mechanical malfunctions or failures that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for WPR12FA316 for the full record.