Air Tractor INC AT-502B accident near Zwingle, Iowa, July 28, 2010
On July 28, 2010 at about 10:30 pm local time, a Air Tractor INC AT-502B, registered N6030U, was substantially damaged in an accident during maneuvering (low-alt flying) near Zwingle, Iowa. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's failure to maintain clearance from wires during the agricultural flight.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 28, 2010 · about 10:30 pm local time
- Place
- Zwingle, Iowa · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Air Tractor INC AT-502B · all AT-502Bs on the register
- Registration
- N6030U · no longer on the register · serial 502B-0323
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that he was conducting agricutural spraying operations in the airplane when the accident occurred. He stated that he had completed a spray pass and made a turn for another pass. As he came out of the turn the airplane was heading west into the afternoon sun. The pilot stated that he misjudged the height of the top wire of poles along the edge of the field. After striking the wire he noted that he had almost no elevator control and executed a landing in a field. The airplane subsequently nosed over. The pilot made no mention of control difficulties prior to striking the wire.
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
- Low altitude operation/event during maneuvering (low-alt flying) defining event
The NTSB's findings
- cause Personnel issues › Psychological › Attention/monitoring › Monitoring environment › Pilot
- Environmental issues › Physical environment › Object/animal/substance › Wire › Effect on equipment
- Environmental issues › Conditions/weather/phenomena › Light condition › Glare › Contributed to outcome
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land; instrument: airplane
- Flight time: 1,900 hours in all; 330 in this make and model
- Last flight review: February 20, 2009
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: sngl
- Injury: minor injuries
The aircraft
- Last inspection: inspection type not recorded
- Seats: 1
- Landing gear: fixed
- Engine: Pratt & Whitney PT6A Series (turboprop); 0 hours total
- Operator: Klinkenborg Aerial Spraying & Seeding INC
The flight
- Departed from: Zwingle IA
- Destination: Zwingle IA
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 330° at 11 knots
- Visibility: 10 statute miles
- Sky: a few clouds at 3,500 ft
- Temperature: 82°F (28°C), dew point 66°F (19°C)
- Altimeter: 30.01 inHg
- Observation at 9:53 pm from DBQ, 10 miles away
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.