Uncontrolled Descent and Disintegration of an Aircraft on the Krasnoyarsk–Petropavlovsk-Kamchatsky Route (CCCP-74252)

Flight Progression and Loss of Control During cruise at an altitude of 8,000 metres on the leg from Krasnoyarsk to Petropavlovsk-Kamchatsky, the crew transmitted a brief, inaudible message lasting two seconds. Shortly afterward, the aircraft entered an uncontrolled descent, with vertical speed recorded between 3,360 and 11,000 feet per minute. As the aircraft descended to 3,000 metres, the vertical speed increased from 9,850 to 24,600 feet per minute. The aircraft then turned to the right, became inverted, and partially disintegrated at an altitude of 650 metres. ## Impact and Casualties Debris impacted the ground at a speed of 890 km/h in an uninhabited area located 13 km northeast of Parchum. The wreckage was scattered over a large area. One passenger was found alive, while 83 other occupants were killed. ## Investigation Findings The official investigation was unable to determine the exact cause of the accident. Investigators did not rule out the possibility that loss of control resulted from a fuel-line failure, which could have allowed fuel to leak into the engine and ignite upon contact with high-temperature equipment.