What happened
On May 2015, an Air Tractor AT-802A Fire Boss, registered as C-FDHV, was participating in wildfire suppression efforts approximately 25 nautical miles northwest of Cold Lake, Alberta. Operating as Tanker 692 for Conair Group Inc., the aircraft was part of a larger formation that included three other AT-802A Fire Boss aircraft and two CL-215T aircraft.
During the mission, the aircraft had successfully performed two drops on the fire, moving from west to east with a northern turnout. As the aircraft was exiting its third drop, it encountered intense turbulence. This led to a sudden nose-up pitch, causing the aircraft to climb to an altitude of roughly 400 to 500 feet above the ground. Following this climb, the aircraft rolled to the left and transitioned into a nose-down attitude. The aircraft subsequently struck the ground with the right wing low and the nose near level. The impact was non-survivable, resulting in one fatality.
The investigation
The investigation focused on the sequence of events leading to the loss of control during the third drop. Investigators examined the aircraft's flight path, the environmental conditions present during the wildfire operation, and the specific atmospheric disturbances encountered by the formation.