Date & Time:
Feb 24, 1973 at 0737 LT
Type of aircraft:
Ilyushin II-18
Operator:
Registration:
CCCP-75712
Flight Phase:
Flight
Flight Type:
Scheduled Revenue Flight
Survivors:
No
Site:
Plain, Valley
Schedule:
Dushanbe - Leninabad - Moscow
MSN:
189 0018 04
YOM:
1959
Flight number:
SU630
Country:
Tajikistan
Region:
Asia
Crew on board:
8
Crew fatalities:
8
Pax on board:
71
Pax fatalities:
71
Other fatalities:
0
Total fatalities:
79
Aircraft flight hours:
20404
Aircraft flight cycles:
9590
Circumstances:
While cruising at an altitude of 6,600 meters, the crew received the permission to descent to 4,500 meters when the automatic pilot system was deactivated. Suddenly, the airplane banked left to an angle of 90° then entered a dive. At an altitude of 2,200 meters, due to excessive g loads, the left wing separated and the aircraft caught fire. Out of control, it crashed at a speed of 840 km/h in an open field located 8,4 km southeast of Buston Station, about 38 km northwest of Leninabad Airport. The aircraft disintegrated on impact and all 79 occupants have been killed.
Probable cause:
The exact cause of the accident could not be determined with certainty. However, the assumption that the loss of control, that occurred just after the automatic pilot system has been deactivated, was caused by the failure of an attitude indicator was not ruled out.
