An Aeroflot Yak-42 in 1981, similar to the accident aircraft | |
Accident | |
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Date | 28 June 1982 (1982-06-28) |
Summary | Jackscrew failure due to metal fatigue; design flaw |
Site | Near Mazyr, Byelorussian SSR, Soviet Union 52°0′N 29°13′E / 52.000°N 29.217°E / 52.000; 29.217 |
Aircraft | |
Aircraft type | Yakovlev Yak-42 |
Operator | Aeroflot |
Registration | СССР-42529 |
Flight origin | Pulkovo Airport, Leningrad, Russian SFSR, Soviet Union |
Destination | Kiev (now Kyiv)-Zhuliany International Airport, Kiev, Ukrainian SSR, Soviet Union |
Occupants | 132 |
Passengers | 124 |
Crew | 8 |
Fatalities | 132 |
Survivors | 0 |
Aeroflot Flight 8641 was a Yakovlev Yak-42 airliner on a domestic scheduled passenger flight from Leningrad (now Saint Petersburg) to Kiev (now Kyiv). On 28 June 1982, the flight crashed south of Mazyr, Byelorussian SSR, killing all 132 people on board. The accident was both the first and deadliest crash of a Yakovlev Yak-42, and remains the deadliest aviation accident in Belarus.
The cause was a failure of the jackscrew controlling the horizontal stabilizer due to a design flaw.
The Yakovlev Yak-42 involved in the accident was registered to Aeroflot as СССР-42529 (manufacturer number 11040104, series number 04-01). The aircraft made its maiden flight on 21 April 1981 and was delivered to Ministry of Civil Aviation on 1 June 1981. At the time of the accident, it had 795 flight hours and 496 takeoff and landing cycles.
All 124 passenger seats were filled, 11 by children. The cockpit crew consisted of:
The aircraft took off from Pulkovo Airport at 9:01 Moscow time, having been delayed one minute because of a late passenger. At 10:45 it entered the zone of Kiev/Boryspil air traffic control Center. The crew started the landing checklist at 10:48:01. At 10:48:58 the crew informed the air traffic controller they reached the planned top of descent point, the controller clearing them for descent to FL255 (approximately 25,500 feet (7,800 m)). The crew confirmed the flight path; no further communications were heard from Flight 8641.
At 10:51:20 the autopilot gradually brought about a horizontal stabilizer angle of up 0.3° for descent for landing. At 10:51:30 the stabilizer angle sharply increased, exceeding the 2° limit within half a second. The sudden change resulted in a negative g-force of -1.5 g, but the autopilot adjusted the controls to lower it to -0.6 g. As the stabilizer did not respond to commands and the plane went on diving, the autopilot switched off after 3 seconds. The pilots pulled back on the yoke trying to level out the plane, but it continued into a steep dive; soon it rolled 35° left and the dive achieved 50°. As it rolled counterclockwise with over -2 g of overload, the aircraft disintegrated at 10:51:50 at the altitude of 5,700 metres (18,700 ft) and the instrument speed of 810 kilometres per hour (440 kn; 500 mph).
The wreckage was found on the outskirts of Verbavychi village, 10 kilometres (6.2 mi) southeast of the district center Naroulia (itself being further 18 km south/west of the larger Mozyr which is often listed.) Fragments of the plane were scattered across an area of 6.5 by 3.5 kilometres (4.0 by 2.2 mi). All 132 people on board perished.
The cause was determined to be a failure of the jackscrew mechanism in the aircraft's tail due to metal fatigue, which resulted from flaws in the Yak-42's design. The investigation concluded that among the causes of the crash were poor maintenance, as well as the control system of the stabilizer not meeting basic aviation standards. Three engineers who signed the jackscrew drawings were convicted.
As for the official cause of the crash: "the spontaneous movement of the stabilizer was due to disconnection in flight of the jackscrew assembly due to the almost complete deterioration of the 42M5180-42 thread-nuts due to structural imperfections in the mechanism." Due to the accident, all Yak-42s were withdrawn from service until the design defect was rectified in October 1984.
Aviation accidents and incidents in 1982 (1982) | |
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Jan 13 Air Florida Flight 90Jan 18 Thunderbirds Indian Springs "Diamond Crash"Jan 23 World Airways Flight 30Feb 6 Korean Air Force C-123 crashFeb 9 Japan Air Lines Flight 350Feb 21 Pilgrim Airlines Flight 458Mar 11 Widerøe Flight 933Mar 20 Garuda Fokker F28 crashMar 26 Aeropesca Colombia Flight 217Apr 26 CAAC Flight 3303May 25 RAF Jaguar shootdown incidentJun 6 British Army Gazelle friendly fire incidentJun 8 VASP Flight 168Jun 12 TABA Fairchild FH-227 accidentJun 21 Air India Flight 403Jun 24 British Airways Flight 009Jun 28 Aeroflot Flight 8641Jul 6 Aeroflot Flight 411Jul 9 Pan Am Flight 759Jul 23 Twilight Zone accidentAug 11 Pan Am Flight 830Aug 26 Southwest Air Lines Flight 611Sep 1 Aerocondor DHC-4 Caribou accidentSep 13 Spantax Flight 995Sep 13 Bristow Helicopters Bell 212 accidentSep 17 Japan Airlines Flight 792Sep 29 Aeroflot Flight 343Dec 9 Aeronor Flight 304Dec 24 CAAC Flight 2311 | |
1981 ◄ ► 1983 |
Aviation accidents and incidents in the Soviet Union | |||||||||||||
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52°3′0″N 29°16′0.12″E / 52.05000°N 29.2667000°E / 52.05000; 29.2667000