Amateur-built Cozy N9699 accident near Aurora, Oregon

Probable cause

The pilot’s failure to maintain control of the airplane following a loss of engine power in the traffic pattern; the cause of the loss of engine power for reasons that could not be determined because postaccident examination of the airframe and engine did not reveal any anomalies that would have precluded normal operation.

NTSB analysis

According to a witness, while the airplane was in the traffic pattern, he heard "strange noises" emanating from the engine. A plot from an onboard global positioning system unit indicated that the airplane had completed one takeoff and landing, and a second orbit of the traffic pattern had occurred. The track then showed the airplane turn back toward the middle of the runway at a 45-degree angle before the airplane reached the downwind leg. The track showed the airplane then turn right to parallel the runway. Near the end of the runway, the airplane turned left and crashed. Total elapsed time was about 11 minutes. The pilot was likely attempting to land on a taxiway due to the loss of engine power described by the witness; however, the airplane struck the top of a hangar and came to rest inverted. A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for WPR10LA456 for the full record.