Probable cause
A total loss of engine power during cruise flight due to the failure of a cylinder exhaust valve stem, which led to a forced landing during which the airplane impacted terrain.
NTSB analysis
The pilot stated that, during cruise flight, the airplane experienced “significant” vibration, which was followed by a total loss of engine power. The pilot performed a forced landing to a field, during which the airplane nosed over and impacted terrain.
Postaccident examination of the airplane engine revealed that the No. 4 cylinder exhaust valve stem was broken at its base and the seat was turned sideways. Pieces of the stem were found in the cylinder. The failure of the exhaust valve resulted in reduced engine compression leading to the total loss of engine power.
Text from the NTSB. Open the NTSB docket for CEN21LA359 for the full record.
Event
- Date
- Aug 6, 2021
- Type
- Accident
- Place
- Gosport, Indiana
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Day
Piper J3C-65
- N-number
- N6269H
- Category
- Airplane
- Year built
- 1946
- Damage
- Substantial
- Operating rule
- Part 91 (general aviation)
- Purpose of flight
- Personal
From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.