Probable cause
The pilot's inadequate visual lookout during an aerial application run, which resulted in an in-flight collision with a windmill.
NTSB analysis
During an aerial application flight, the pilot had completed a spray run and initiated a climb to clear trees at the end of the field. The pilot reported that several trees and windmills were located at the southern end of the field and as the airplane made a climbing left turn, the right wing struck a windmill blade. The collision tore the spray boom from the airplane, which then impacted the airplane’s right side stabilizer and fuselage, causing substantial damage. The pilot was able to perform a successful landing on a nearby gravel road.
Text from the NTSB. Open the NTSB docket for CEN11CA545 for the full record.
Event
- Date
- Jul 28, 2011
- Type
- Accident
- Place
- Forest City, Iowa
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Day
Ayres Corporation S2R-G6
- N-number
- N331BF
- 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.