The former Soviet air fleet has been plagued by chronic safety problems since the 1991 collapse of the union and the break-up of the former state airline Aeroflot into some 400 companies.
Accidents involving former Soviet aircraft have generally been attributed to cash shortages, which lower already poor maintenance standards and place extra pressure on air crews.
Safety concerns
Ageing aircraft
Poor maintenance
Obsolete air traffic control system
Concern is frequently expressed about safety standards in many of the small airlines, many of them using some of the older planes shed by the giant Aeroflot.
The ageing Tupolev 154 remains popular with the airlines of the former Soviet Union, despite the emergence of safety fears following numerous crashes.
More than 1,000 Tu-154s have been built and most remain active.
Apart from ageing aircraft and insufficient maintenance, serious concern has been expressed over the air traffic control system in the region. Much of its equipment is obsolete and was now incompatible with the international air navigation system
However, in recent years, the safety record of former Soviet airlines has improved, and the last serious crash involving an airliner from the former Soviet Union was in 1997.
Some of the more serious passenger plane crashes of recent years include: