What happened
Shortly after departing from Leningrad-Pulkovo Airport, the flight crew reported a failure of the fourth engine to air traffic control. During the initial climb phase, which occurred less than three minutes after takeoff, an emergency was declared and the aircraft was authorized to return to the airport.
Approximately three minutes following the initial engine failure, the number four engine experienced an explosion and caught fire. As the aircraft approached for its final landing, it became uncontrollable, pitching downward at a 60-degree angle. The plane struck an open field roughly 2,480 meters before reaching the runway, resulting in a massive explosion. The impact caused the aircraft to disintegrate, with much of the wreckage located 242 meters to the right of the runway centerline. There were 109 fatalities in the accident.
Findings
Investigations revealed that the disintegration of the third stage of the high-pressure turbine occurred two minutes and 53 seconds after takeoff. This failure led to the subsequent engine explosion three minutes later. During this event, flying debris struck the right aileron, causing it to become jammed in a downward position while the left aileron remained upward. This asymmetric control surface configuration was a primary factor in the loss of aircraft control during the final approach.