Probable cause
Internal failure of the engine for undetermined reasons.
NTSB analysis
The agricultural airplane was maneuvering at 500 feet above ground level when the engine lost power, and oil immediately covered the windscreen. During the forced landing, the airplane impacted a dirt berm and came to rest in a ditch. A postaccident examination of the engine showed a hole in the side of the No. 5 cylinder, which is located at the bottom of the engine. The examination also revealed that several of the connecting rods, including the No. 5 master rod, were broken. There was no evidence in the engine of scoring, thermal damage, or oil starvation. Due to the extent of the engine damage, the initial failure mode could not be determined. At the time of the accident, the engine had accumulated 43 hours since major overhaul.
Text from the NTSB. Open the NTSB docket for CEN11LA541 for the full record.
Event
- Date
- Jul 30, 2011
- Type
- Accident
- Place
- Hettinger, North Dakota
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Day
Weatherly Aviation Co Inc 620B
- N-number
- N90181
- 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.