Accident Overview
On June 20, 2024, at 1258 mountain daylight time, an Air Tractor AT-802 (registration N802AT) and an Air Tractor AT-502B (registration N581TW) were destroyed in a mid-air collision near Arco, Idaho. The pilot of the AT-802 was seriously injured, and the pilot of the AT-502B sustained fatal injuries. Both aircraft were operated under Title 14 Code of Federal Regulations Part 137 for aerial application flights. Both airplanes were owned by the same operator, and both pilots were employed by that operator.
Flight Operations
According to the operator, both airplanes operated from the Arco-Butte County Airport (AOC) on the day of the accident. Operations began around 0530, and each aircraft had conducted multiple aerial application flights within 10 miles of AOC prior to the collision. The AT-502B departed AOC about 1230 with 400 gallons of a fungicide and insecticide mixture intended for wheat. The AT-802 departed AOC about 1245 with full fuel tanks and 575 gallons of insecticide for potatoes.
Data from a recovered iPad using the AgPilotX application showed the AT-802 applying chemicals to potato fields no. 10 and no. 11 north of US Highway 26. Field no. 11 was immediately adjacent to the highway, and field no. 10 was adjacent to field no. 11 to the northwest. The application data indicated that the AT-802 was making northwest and southeast passes over both fields. The AT-802 was not equipped with ADS-B equipment.
The AT-502B was equipped with ADS-B. Preliminary ADS-B derived data from a commercially available source showed the flight path began with the AT-502B flying west then east tracks about 5 miles northwest of AOC over wheat fields no. 2 and no. 3. The airplane then flew southeast before turning south, overflying the fields being worked by the AT-802. The last ADS-B target for the AT-502B was north of the accident site, over US Highway 26.
Witness Observations
Two witnesses traveling westbound on US Highway 26 observed one airplane traveling from north to south over the highway at low altitude. They also saw a second airplane traveling toward the first on a northerly heading. They reported that the southbound airplane appeared to make a left turn in front of the northbound airplane. The northbound airplane then appeared to make a left turn to avoid the first airplane before they collided.
Wreckage Distribution
The accident site encompassed three areas of wreckage: the main wreckage of each airplane and a debris field located about midway between the two fuselages. Both airplanes and associated debris came to rest on flat, sagebrush-covered terrain south of US Highway 26. The main wreckage of the AT-802 was located about 450 feet south of the highway, with a debris path oriented on a magnetic heading of about 220°. The main wreckage of the AT-502B was located about 1,900 feet south of the highway and about 1,600 feet southeast of the AT-802. The debris path of the AT-502B was oriented on a magnetic heading of about 105°. Portions of both airplanes’ right wings were located within the debris field between the two main wreckages.