Collision
On an unspecified date, a crew was approaching Leningrad-Shosseynaya Airport and received permission from air traffic control (ATC) to descend to 1,200 meters via corridor number two. While entering clouds, the aircraft collided with an Aeroflot Douglas TS-62 registered CCCP-L1055. That aircraft was performing flight SU381 to Minsk with seven people on board and had just taken off from the same airport. Its crew had received permission to climb to 2,700 meters via the same corridor number two.
At an altitude of 1,200 meters, the two aircraft collided. Both dove into the ground and crashed in a field near the village of Skvoritsy, approximately 23 km southwest of Leningrad-Shosseynaya Airport.
Wreckage and Casualties
The wreckage of both aircraft was found 1,200 meters apart. All 31 occupants of both aircraft were killed.
Probable Cause
The official investigation determined that the collision was caused by an error on the part of ATC services. Despite both aircraft being tracked on radar screens, ATC based at Leningrad-Shosseynaya Airport failed to take appropriate actions to ensure a minimum safe separation between the two airplanes and failed to realize that they were flying in the same corridor in opposite directions at the same altitude. The collision resulted from successive errors by ATC personnel, including failure to ensure efficient radar surveillance and transmission of inappropriate instructions that led both aircraft onto the same track.