Flight History
On June 29, 2017, at approximately 0740 central daylight time, an Air Tractor AT602 airplane, registration N4196Y, was destroyed after colliding with terrain near Stirum, North Dakota. The pilot was fatally injured. The aircraft was operated by Wilbur-Ellis Company under 14 Code of Federal Regulations Part 137 as an aerial application flight. It departed from Lisbon Municipal Airport (6L3) in Lisbon, North Dakota, around 0700. The flight was not operated on a flight plan, and instrument meteorological conditions prevailed at the accident site.
The airplane was loaded with product around 0500, but departure was delayed about two hours while the pilot waited for local weather to improve. Before the flight, the pilot spoke with individuals by phone to assess conditions. An employee reported that flying had been limited to mornings in preceding days due to afternoon winds. At departure, visibility was about 1.5 miles with overcast clouds, light wind, and no precipitation.
Witness Accounts
A witness sitting on her patio heard the airplane with a normal engine sound. She saw it emerge from fog heading east and impact the ground within seconds. The airplane appeared level or slightly descending, with no change in flight path before striking gradually rising terrain. She noted it did not seem out of control or have mechanical issues. The witness described it as "very, very foggy" and could barely make out a tree 200 yards away. There was no precipitation and little wind.
A second witness at the same location heard the airplane heading northeast toward Lisbon but did not see it. He estimated about 200 feet of relatively good visibility below the fog/cloud layer. The ground rises gradually approaching his property from the west, with an elevation difference of about 56 feet over half a mile.
Weather Conditions
An AIRMET advisory for instrument flight rules conditions was active at the time, with the accident site near the southwestern extent of the advisory. The area forecast predicted broken clouds at 2,000 feet mean sea level and visibility of 3 to 5 miles in mist until 1000. There was no record of the pilot obtaining a preflight weather briefing through Lockheed Martin Flight Service, DUATS, or Foreflight, though he may have used a commercial service that did not track individual activity.
Wreckage Examination
The airplane impacted a soybean field about 14 miles west-southwest of Lisbon Municipal Airport. No obstacles like large trees, power lines, or towers were nearby. The main wreckage came to rest about 150 feet from the initial ground impact crater, with a debris field approximately 280 feet long. Ground marks consistent with propeller slashes were near the impact point. A ground depression and impact scar adjacent to the crater appeared consistent with the right main landing gear. The right aileron counterweight separated and was embedded in the ground near the end of the impact mark.
A postaccident examination by FAA inspectors and an airframe manufacturer representative found no anomalies consistent with a preimpact failure or malfunction. Details are included in the docket.
Medical and Toxicology
The University of North Dakota Forensic Pathology Office performed an autopsy, attributing the pilot's death to blunt force trauma. The FAA Bioaeronautical Sciences Research Laboratory conducted toxicology tests on pilot specimens, which were negative for all substances in the testing profile.
Advisory
In response to the accident, the National Agricultural Aviation Association issued an advisory to member operators as part of the Fly Safe Campaign, warning pilots about hazards of low-level instrument conditions and emphasizing thorough preflight weather briefings.