Pilot’s Failure to Deconflict Altitude Caused 2017 Weapons School Crash

MF simulation (viewed from above) 0.1 seconds prior to collision. Investigation documents photo.

An A-10 pilot’s unintentional failure to stick to altitude deconfliction, coupled with task over-saturation, a misperception of the changing environment, and environmental conditions caused two Warthogs to collide during US Air Force Weapons School training last year near Nellis AFB, Nev.

The two pilots, assigned to the 57th Wing at Nellis, were able to eject during the Sept. 7, 2017, crash and only suffered minor injuries. The two Warthogs were destroyed at a total cost of $30.7 million, with environmental cleanup cost of $108,000, according to an Air Combat Command Accident Investigation Board report released Thursday.

The pilots were flying a close air support training mission at night as part of a Weapons Instructor Course qualification for one of the pilots, with the second flying as the instructor. During the flight, the student pilot climbed above the assigned altitude block during a series of commands, did not hear an audible notification that signaled the altitude climb, and therefore did not radio to the instructor to deconflict, according to the investigation.

This caused the student pilot’s aircraft to fly into altitude designated for the instructor, who did not have line of sight on the other A-10. The two aircraft collided, rendering both uncontrollable. The pilots then ejected.

The investigation determined the student pilot unintentionally failed to establish the altitude deconfliction procedure. Additionally, the board president found that the upgrading pilot was handling communications on multiple radios and had many tasks, causing oversaturation. The first pilot had a misperception of the changing environment, though the aircraft’s systems for showing the altitude were working. While both pilots were using night vision goggles, their A-10s had external lights off which made it difficult to discern each other’s position, the report states.