What happened
During a flight at an altitude of 8,000 meters, a four-engine aircraft experienced a sudden loss of control while operating in favorable weather conditions. The aircraft entered a steep dive, reaching a descent angle of 107° and accelerating to a speed of 630 km/h. The plane eventually struck a snow-covered field situated approximately 10 km east of Chebotovka, in the Rostov region. The impact caused the aircraft to disintegrate, and there were 59 fatalities among the occupants.
Findings
Investigations into the accident concluded that the loss of control was triggered by an error made by the flight mechanic. During the cruise phase of the flight, the mechanic unintentionally moved the flaps to a 40° position. This action significantly decreased the longitudinal stability of the aircraft, leading to the rapid loss of control. A contributing factor identified in the investigation was that the flap lever lacked sufficient protection to prevent such accidental movement.