Beech 36 N630JL accident near Independence, Missouri

Probable cause

Failure of the No. 5 piston head and ring, which resulted in a total loss of engine power and the pilot’s decision to takeoff with a known mechanical issue.

NTSB analysis

During the initial climb, the pilot noted a rising cylinder head temperature which shortly after led to the airplane oscillating back and forth and responding slowly. The pilot set up for a forced landing and the airplane began to shake and was unable to hold altitude. During the approach to landing, the engine quit, and the pilot minimized his bank angle to stay out of a stall situation. When the airplane touched down, the pilot lost directional control and the airplane skidded off the road into a grassy area. The airplane sustained substantial damage to the wings and fuselage.

The pilot reported that on the previous flight, he was in cruise flight at 8,000 ft when he noted that the airplane began “moving back and forth.” He scanned the instruments and saw the cylinder head temperatures (CHT) for the Nos. 5 and 6 cylinders were “running in the red” along with oil temperature. The pilot diverted and landed uneventfully. During the descent for landing, the engine temperatures returned to normal, and he landed uneventfully.

The pilot called the owner and discussed what had occurred. The owner suggested that if the pilot was comfortable, he should return to the home airfield. The pilot agreed to return if the taxi and engine run-up checked normal. The engine run-up was normal, and the pilot departed the airport without incident.

Postaccident examination of the engine found that the No. 5 cylinder head and piston ring had failed with signatures of denotation. Additionally, the turbocharger oil seal had failed. The pilot stated that he was not running the engine lean with fuel.

Text from the NTSB. Open the NTSB docket for CEN20LA288 for the full record.