Cessna R182 N639RR accident near Crowley, Louisiana

Probable cause

The failure of the No. 4 cylinder exhaust valve that resulted in a partial loss of engine power. Based on available evidence, the reason for the failed valve was not determined.

NTSB analysis

About 30 minutes into the aerial observation flight, the engine began "popping" and running rough. The pilot was unable to maintain sufficient engine RPMs and elected to return to the departure airport for a precautionary landing. Based on the airplane's location relative to the runway orientation, the pilot performed a downwind landing. During the approach, the airplane was "a little high and fast;" however, the pilot was committed to the landing due to the reduced engine performance. The airplane touched down, overran the end of the turf runway impacted a ditch and came to rest upright. Both wings and the fuselage sustained substantial damage. Postaccident examination of the engine revealed the No. 4 engine cylinder exhaust valve was stuck which resulted in a bent push rod and partial loss of engine power. Due to damage to the operator's facility and the airplane from hurricane activity, further examination of the engine was not conducted and the reason for the stuck valve was not determined.

Text from the NTSB. Open the NTSB docket for CEN20LA361 for the full record.