Air Tractor INC AT 402 accident near Sac City, Iowa, July 29, 2016
On July 29, 2016 at about 2:14 pm local time, a 1989 Air Tractor INC AT 402, registered N1016G, was destroyed in an accident during maneuvering near Sac City, Iowa (Sac City Muni airport). It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 1 person was killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's failure to maintain adequate clearance from power lines. Contributing to the accident was the pilot's failure to circle over the field to identify hazards before beginning the aerial application.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 29, 2016 · about 2:14 pm local time
- Place
- Sac City, Iowa · Sac City Muni · map
- Type
- Accident
- Injuries
- 1 person was killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Air Tractor INC AT 402, built 1989 · all AT 402s on the register
- Registration
- N1016G · no longer on the register · serial 402-0720
- Damage
- Destroyed
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
The commercial pilot was performing an aerial application flight to an area that a ground crewman described as a "wire farm" due to the number of power lines present. The pilot did not complete a circling pass over the target field to identify hazards before descending for the first aerial application pass. The pilot flew over a set of power lines, activated the airplane's spray function, and completed one pass to the north. The airplane then climbed and made a left turn before descending toward the west side of the target field for a pass to the south. The pilot completed a pass on the west side, then impacted power lines on the south side of the field. The airplane continued south and impacted a corn field, where it came to rest upright. The top of the vertical stabilizer and the rudder were found near the power lines. A postaccident examination of the airplane revealed evidence of multiple wire strikes to the canopy, wire protection system, and empennage. At least one wire was deflected over the canopy, along the wire deflector cable, and cut through the vertical stabilizer and rudder. At least one wire impacted the aluminum wire protection bar and the cockpit structure consistent with the wire not deflecting over the canopy. The examination did not reveal any preimpact anomalies that would have precluded normal operation.
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
- Controlled flight into terrain or object (CFIT) during maneuvering defining event
The NTSB's findings
- cause Personnel issues › Action/decision › Info processing/decision › Identification/recognition › Pilot
- cause Environmental issues › Physical environment › Object/animal/substance › Wire › Awareness of condition
- cause Environmental issues › Physical environment › Object/animal/substance › Wire › Effect on equipment
- factor Personnel issues › Task performance › Planning/preparation › Flight planning/navigation › Pilot
- factor Environmental issues › Physical environment › Object/animal/substance › Wire › Decision related to condition
- factor Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Pilot
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land; single-engine sea; instrument: airplane
- Flight time: 1,746.1 hours in all; 414.1 in this make and model
- Last flight review: May 29, 2015
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: sngl
- Injury: fatal
The aircraft
- Airframe total time: 7,008.3 hours
- Last inspection: annual inspection, May 12, 2016; 108 hours since
- Seats: 1
- Landing gear: fixed
- Engine: Pratt & Witney Canada PT6A-27 (turboprop); 14,963 hours total
- Operator: Watson Ag Aviation LLC
The flight
- Departed from: CIN Carroll IA at 2:02 pm
- Destination: SKI Sac City IA
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 030° at 6 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 68°F (20°C), dew point 61°F (16°C)
- Altimeter: 30.09 inHg
- Observation at 2:15 pm from KSLB, 18 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
12 documents, released by the NTSB on November 3, 2017. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Correspondence - Record of Conversation | PDF, 2 pages | View Download |
| 2 | Pilot Logbook Excerpts | PDF, 4 pages | View Download |
| 3 | Maintenance Records | PDF, 17 pages | View Download |
| 4 | Reports from Parties to the Investigation - Air Tractor | PDF, 18 pages | View Download |
| 5 | Miscellaneous Information - Power Line Company | PDF, 4 pages | View Download |
| 6 | Photos | PDF, 9 pages | View Download |
| 7 | Toxicological Report | PDF, 1 page | View Download |
| 8 | Electronic Devices - Specialist's Factual Report | PDF, 4 pages | View Download |
| 9 | Electronic Devices - Attachment 1 - Tabular Data (Csv) | data file | Download |
| 10 | Satloc Graph | PDF, 1 page | View Download |
| 11 | Statement of Party Representatives to NTSB Investigation | PDF, 1 page | View Download |
| 12 | Release of Aircraft Wreckage, NTSB Form 6120.15 | PDF, 1 page | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
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.