Cessna 182F N3420U accident near Auburn, Alabama

Probable cause

A loss of engine power due to an internal failure of the muffler that was not detected by maintenance personnel.

NTSB analysis

The airplane was approximately 2,700 feet above ground level when the engine stopped producing full power and the airplane began to lose altitude. The pilot elected to land on a road and the airplane subsequently impacted an automobile. No preimpact mechanical anomalies of the engine were noted; however, examination of the muffler assembly revealed that the right internal baffle cone had separated from the surrounding structure. It was possible for the separated baffle cone to partially block the exhaust exit; however, its position as found would not have resulted in a loss of engine power. The airplane had been operated for about 2 hours since its most recent annual inspection, which was performed about 5 months prior to the accident. Due to the amount of damage observed to the fracture surfaces of the baffle cone, it was likely that the fracture occurred prior to the annual inspection. Inspection guidance used by the maintenance facility that performed the annual inspection included an inspection of the muffler, heat exchange, and baffles.

Text from the NTSB. Open the NTSB docket for ERA11LA167 for the full record.