Ayres Corporation S2R-G6 accident near Forest City, Iowa, July 28, 2011
On July 28, 2011 at about 11:15 pm local time, a Ayres Corporation S2R-G6, registered N331BF, was substantially damaged in an accident during maneuvering (low-alt flying) near Forest City, Iowa. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's inadequate visual lookout during an aerial application run, which resulted in an in-flight collision with a windmill.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 28, 2011 · about 11:15 pm local time
- Place
- Forest City, Iowa · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Ayres Corporation S2R-G6 · all S2R-G6s on the register
- Registration
- N331BF · registry record · serial G6-102
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
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.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Loss of visual reference during maneuvering (low-alt flying) defining event
- Collision with terrain or object (not controlled flight into terrain) during maneuvering (low-alt flying)
- Off-field or emergency landing during maneuvering (low-alt flying)
The NTSB's findings
- cause Personnel issues › Task performance › (general) › (general) › Pilot
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land
- Flight time: 7,400 hours in all; 240 in this make and model; 280 in the last 90 days; 120 in the last 30 days
- Last flight review: August 1, 2011
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: sngl
- Injury: no injuries
The aircraft
- Airframe total time: 7,000 hours
- Last inspection: 100-hour inspection, July 1, 2011
- Seats: 1
- Landing gear: fixed
- Engine: Airesearch TPE331-5&6SER (turboprop); 0 hours total
- Operator: Central Balley Aviation
The flight
- Departed from: Forest City IA
- Destination: Forest City IA
- Flight plan: not recorded
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 82°F (28°C), dew point 70°F (21°C)
- Altimeter: 29.94 inHg
- Observation at 11:35 pm from KFXY
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.