N10122

On July 10, 2024, about 1210 mountain daylight time, an Air Tractor AT-802A, N10122, was substantially damaged when it was involved in an accident near Helena, Montana. The pilot was fatally injured. The airplane was operated as public use aircraft for the purpose of firefighting.

The operator reported that they dispatched four of their single engine air tankers (SEAT) to Helena for the United States Forest Service (USFS) in support of aerial firefighting efforts for the Horse Gulch Fire. The flight of four departed Coeur d’Alene Airport – Pappy Boyington Field (COE), Coeur d'Alene, Idaho, about 1 hour 44 minutes before the accident, and flew direct to Hauser Lake, where they began scooping water from the lake. The accident airplane was in the No. 2 position. During its first scoop sequence, witnesses on the lake and the pilots of the 2 SEATs flying behind the accident airplane saw the airplane make a left turn to the southwest. Subsequently the airplane impacted a vertical rockface bordering the southern shoreline of the lake, fell into the lake, and sank.

The accident airplane was equipped with a SpiderTracks flight tracking system. The downloaded data (figure 1) showed that after departing COE, the airplane turned to a southeasterly heading and ascended to an altitude of about 9,400 ft mean sea level (msl). The airplane continued on a southeasterly heading, at altitudes between 9,275 ft and 9,575 ft msl, until it began a descent began at 1146. The group of four airplanes overflew Hauser Lake, completed several turns, before they made a descending right turn from the east side of the lake. The accident airplane descended to the lake’s surface, on a track of about 279° magnetic, and traveled about 4,233 ft over the water. The airplane then made a left turn to a heading of 269° and traveled about 1,447 ft. until the data ended in an area of the accident site.

Figure 1: SpiderTracks Image of Flight Track (Courtesy of Operator)

Examination of the accident site revealed that the airplane remained mostly intact and was submerged on the sloped lakebed adjacent to a vertical rockface on the southern edge of the lake. The airplane came to rest on a heading of about 225° magnetic in a tail low attitude in the water, which had a depth that ranged from 10 ft (nose section) to 30 ft (tail section). The propeller assembly was separated and located at the base of the cliff, submerged in water. Both floats were separated from the airframe and remained floating on the surface of the lake. All major structural components of the airplane were located at the accident site.

The wreckage was recovered and transported to a secure location for further examination.