Aeroflot Flight 7425
Encyclopedia
Aeroflot
Flight 7425 refers to a Tupolev Tu-154B-2, registration
CCCP-85311, that was operating a domestic scheduled Tashkent
–Karshi
–Orenburg
–Leningrad
passenger service under the airline's Uzbekistan
division, that crashed near Uchkuduk, Uzbek SSR
, Soviet Union
, while en route its second leg. The crash killed all 200 occupants on board.
of only 400 km/h (248.5 mph), close to stalling speed for that altitude. The low speed caused vibrations which the aircrew incorrectly assumed were engine surges. Using the thrust lever
s to reduce engine power to flight idle, the crew caused a further drop in airspeed to 290 km/h (180.2 mph). The aircraft stalled and entered a flat spin
, crashing into the ground near Uchkuduk, Uzbekistan
, which at that time was in the Soviet Union
. There were no survivors among the 191 passengers and the 9 crewmen.
Vasily Ershov, a veteran Tu-154 pilot and aviation writer, speculates that the reason for the crash might have been the lack of an adequate crew rest. The Tashkent Airport at the time was in half-finished state and lacked proper crew rest facilities. The aircrew in question had flown from Leningrad for a return flight, and despite ostensibly having rested in Tashkent, couldn't get an adequate sleep in those conditions. Fatigue took its toll after the takeoff from Qarshi, with the crew falling asleep during climb, without turning on a stall warning system. They were waked by the shaking of the stalling plane, and mistaking the shakes for engine surges, they reduced the engine power, sending the plane further into a deep stall and unrecoverable flat spin.
It is regarded as the deadliest air disaster in Soviet and Uzbek aviation history
, and as of 2011 has the highest worldwide death toll of any accident involving a Tupolev Tu-154.
Aeroflot
OJSC AeroflotRussian Airlines , commonly known as Aeroflot , is the flag carrier and largest airline of the Russian Federation, based on passengers carried per year...
Flight 7425 refers to a Tupolev Tu-154B-2, registration
Aircraft registration
An aircraft registration is a unique alphanumeric string that identifies a civil aircraft, in similar fashion to a licence plate on an automobile...
CCCP-85311, that was operating a domestic scheduled Tashkent
Tashkent
Tashkent is the capital of Uzbekistan and of the Tashkent Province. The officially registered population of the city in 2008 was about 2.2 million. Unofficial sources estimate the actual population may be as much as 4.45 million.-Early Islamic History:...
–Karshi
Karshi
Karshi may refer to:*Qarshi, city in Uzbekistan*Karachi, aka Karshi, Sindh...
–Orenburg
Orenburg
Orenburg is a city on the Ural River and the administrative center of Orenburg Oblast, Russia. It lies southeast of Moscow, very close to the border with Kazakhstan. Population: 546,987 ; 549,361 ; Highest point: 154.4 m...
–Leningrad
Leningrad
Leningrad is the former name of Saint Petersburg, Russia.Leningrad may also refer to:- Places :* Leningrad Oblast, a federal subject of Russia, around Saint Petersburg* Leningrad, Tajikistan, capital of Muminobod district in Khatlon Province...
passenger service under the airline's Uzbekistan
Uzbek SSR
The Uzbek Soviet Socialist Republic , also known as the Uzbek SSR for short, was one of the republics of the Soviet Union since its creation in 1924...
division, that crashed near Uchkuduk, Uzbek SSR
Uzbek SSR
The Uzbek Soviet Socialist Republic , also known as the Uzbek SSR for short, was one of the republics of the Soviet Union since its creation in 1924...
, Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
, while en route its second leg. The crash killed all 200 occupants on board.
Description of the accident
The aircraft was cruising at an altitude of 11600 m (38,057.7 ft) with an airspeedAirspeed
Airspeed is the speed of an aircraft relative to the air. Among the common conventions for qualifying airspeed are: indicated airspeed , calibrated airspeed , true airspeed , equivalent airspeed and density airspeed....
of only 400 km/h (248.5 mph), close to stalling speed for that altitude. The low speed caused vibrations which the aircrew incorrectly assumed were engine surges. Using the thrust lever
Thrust lever
Thrust levers are found in the cockpit of aircraft, and are used by the pilot, copilot, or autopilot to control the power output of the aircraft's engines....
s to reduce engine power to flight idle, the crew caused a further drop in airspeed to 290 km/h (180.2 mph). The aircraft stalled and entered a flat spin
Spin (flight)
In aviation, a spin is an aggravated stall resulting in autorotation about the spin axis wherein the aircraft follows a corkscrew downward path. Spins can be entered intentionally or unintentionally, from any flight attitude and from practically any airspeed—all that is required is sufficient yaw...
, crashing into the ground near Uchkuduk, Uzbekistan
Uzbekistan
Uzbekistan , officially the Republic of Uzbekistan is a doubly landlocked country in Central Asia and one of the six independent Turkic states. It shares borders with Kazakhstan to the west and to the north, Kyrgyzstan and Tajikistan to the east, and Afghanistan and Turkmenistan to the south....
, which at that time was in the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
. There were no survivors among the 191 passengers and the 9 crewmen.
Vasily Ershov, a veteran Tu-154 pilot and aviation writer, speculates that the reason for the crash might have been the lack of an adequate crew rest. The Tashkent Airport at the time was in half-finished state and lacked proper crew rest facilities. The aircrew in question had flown from Leningrad for a return flight, and despite ostensibly having rested in Tashkent, couldn't get an adequate sleep in those conditions. Fatigue took its toll after the takeoff from Qarshi, with the crew falling asleep during climb, without turning on a stall warning system. They were waked by the shaking of the stalling plane, and mistaking the shakes for engine surges, they reduced the engine power, sending the plane further into a deep stall and unrecoverable flat spin.
It is regarded as the deadliest air disaster in Soviet and Uzbek aviation history
Aviation history
The history of aviation has extended over more than two thousand years from the earliest attempts in kites and gliders to powered heavier-than-air, supersonic and hypersonic flight.The first form of man-made flying objects were kites...
, and as of 2011 has the highest worldwide death toll of any accident involving a Tupolev Tu-154.