Investigation Summary
Aeroflot Flight 630 was cruising at 6,600 meters (21,700 feet) on a flight from Dushanbe to Moscow, with a scheduled intermediate stopover at Leninabad. The aircraft was required to perform a 60-degree right turn toward Leninabad. For unknown reasons, the aircraft initially turned only 10 degrees and continued on that heading for three minutes with the autopilot engaged. Upon realizing the deviation, the crew disengaged the autopilot and initiated a right turn. After completing the 60-degree turn, the aircraft unexpectedly began banking to the left at a rate of 3 to 4 degrees per second. The bank angle increased until it reached 90 degrees, sending the aircraft into a high-speed spiral dive. The vertical speed reached 100 meters per second, subjecting the airframe to G-forces beyond its structural limits. The aircraft broke apart at approximately 2,200 meters (7,200 feet) before impacting the ground.
Final Conclusions
The official investigation found no evidence of mechanical or structural failure prior to the loss of control. The Ministry of Aviation Industry concluded the accident was caused by a navigation error followed by an aggressive corrective maneuver. The crew's attempt to perform an intense left bank and descent led to a loss of control and subsequent structural failure due to high dynamic loads. The investigation also noted that Air Traffic Control failed to track the flight during its final stages.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Ivan Artemovich Mordovets
Co-pilot
Igor Georgievich Pustovoytov
Navigator
Viktor Vasilyevich Shchepkin
Flight Engineer
Leonid Vasilyevich Kasyanov
Radio Operator
Nikolai Mikhailovich Laptinov
Systems & Failure Modes
Autopilot
Engaged during the initial navigation error; its disengagement preceded the fatal loss of control.
Airframe Structure
Suffered catastrophic failure at 2,200 meters due to aerodynamic loads exceeding design limits during the spiral dive.
Interesting Facts
- 01The aircraft had accumulated 20,404 flight hours and 9,590 pressurization cycles at the time of the crash.
- 02The debris field covered an area of 1,200 by 550 meters.
- 03All 79 occupants, including five children, were killed in the accident.
- 04The aircraft was powered by four Ivchenko AI-20K turboprop engines.