Accident Summary
A cargo aircraft operating a flight from Anadyr Airport in Russia to Baku, Azerbaijan, crashed into an icy river following a loss of control at cruising altitude. All five passengers and five crew members on board were killed.
Flight Details
The flight departed Anadyr with intermediate stops planned in Chokurdakh and Tiksi before continuing to Baku. The aircraft was carrying five passengers and five crew members at the time of the accident.
Accident Sequence
While cruising at night, the aircraft experienced violent oscillations, pitching up and down repeatedly. It then entered an uncontrolled descent. At an altitude of approximately 2,000 meters, the aircraft partially disintegrated due to aerodynamic forces. It subsequently struck an icy river at a speed of 670 km/h, resulting in the destruction of the aircraft and the deaths of all occupants.
Investigation Findings
The official investigation determined the probable cause of the accident. The crew disengaged and re-engaged the automatic pilot system several times for reasons that could not be determined. These actions caused movements of the tail and elevators. The crew's response to these movements was inappropriate. Consequently, the aircraft developed violent oscillations on both the roll and pitch axes and entered an uncontrolled descent. The partial disintegration was the result of aerodynamic forces that exceeded the aircraft's certification limits.