Flight Details
The aircraft departed from Karsi Airport. After takeoff, it climbed at an insufficient speed of 470 km/h against a maximum speed of 515 km/h. The aircraft reached its cruising altitude of 11,600 meters after 40 minutes and 20 seconds.
Incident Sequence
Upon reaching cruising altitude, the aircraft's speed dropped to 400 km/h. The aircraft then reached a critical angle of attack of +20°, at which point vibrations began. The crew misinterpreted these vibrations and, failing to properly judge the situation, reduced engine power to idle. Subsequently, the speed dropped to 290 km/h, and the aircraft stalled, entering a spin. The aircraft eventually adopted a flat attitude and crashed in an isolated, desert area in the region of Ushquduq.
Aftermath
The aircraft was totally destroyed upon impact. All 200 occupants were killed.
Investigation and Probable Cause
The official investigation determined that the climb configuration was incorrect. The crew led the aircraft to adopt a critical angle of attack once cruising altitude was reached. This situation affected the airflow into the three engines, placing the aircraft into inappropriate flight conditions. The crew misinterpreted the situation and failed to identify the wrong flight configuration until the aircraft entered a stall condition.