Accident Overview
On a crop spraying mission to treat forests, an Antonov An-2 (registration RA-81519) departed Kyren Airport. Approximately 40 minutes into the flight, while cruising at 140 km/h, the crew encountered downdrafts, causing the aircraft to lose altitude. Operating in mountainous terrain, the crew initiated a right turn, but the descent continued. The captain attempted an emergency landing; at 85 km/h, the aircraft struck trees and crashed in a wooded area located 16 km southeast of Dabady.
Injuries and Damage
Both pilots sustained injuries and were evacuated to Irkutsk a day after the accident. The aircraft sustained damage beyond repair.
Probable Cause and Contributing Factors
The official investigation determined that the accident likely resulted from the crew flying the route in mountainous terrain to the area of agricultural work (AHR) at an altitude insufficient to ensure safety. This prevented crossing a mountain pass and necessitated an emergency landing, leading to the damage.
Contributing factors identified include: the crew's failure to consider a significant increase in outside air temperature during the day; incorrect altimeter setting; lack of instrument monitoring of flight altitude; downdraft air currents on the leeward side of the mountain slope; and operating fatigue, which diminished attention and situational awareness.