Probable cause
The total failure of a cylinder head assembly. Contributing to the accident was the lack of suitable terrain for a forced landing.
NTSB analysis
The pilot was spraying a corn field; as he was making an aerial application pass, a cylinder on the engine cracked and the engine lost power. The pilot made a forced landing in a nearby field. The airplane crossed a road at a speed of approximately 25 mph and the tail bounced up. After crossing the road, the main tires settled into soft earth and the airplane nosed over. In addition to a bent propeller and "minor top wing damage," the vertical stabilizer was crushed.
Text from the NTSB. Open the NTSB docket for DEN08CA135 for the full record.
Event
- Date
- Aug 6, 2008
- Type
- Accident
- Place
- Walsh, Colorado
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Dawn
Grumman G-164A
- N-number
- N7487
- 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.