Probable cause
Separation of the No. 3 cylinder exhaust valve rocker arm, which resulted in a loss of engine power.
NTSB analysis
The pilot was about 2 miles from the departure airstrip when the engine lost power. The pilot began to dump the fertilizer load and landed straight ahead in a flooded rice field. Upon touchdown, the airplane nosed over, resulting in substantial damage to the airplane. Examination of the engine revealed a crack radiating from the exhaust valve rocker box on the No. 3 cylinder, where the rocker arm bolt attaches to the rocker arm. The top of the rocker box separated, causing the rocker arm to fail.
Text from the NTSB. Open the NTSB docket for CEN11LA556 for the full record.
Event
- Date
- Aug 18, 2011
- Type
- Accident
- Place
- El Campo, Texas
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Day
Grumman G-164A
- N-number
- N6567
- Category
- Airplane
- Damage
- Substantial
- Operating rule
- Part 137 (agricultural)
- Purpose of flight
- Aerial application
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.