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Last updated: 29 November 2021
Date:Wednesday 24 February 1999
Type:Silhouette image of generic T154 model; specific model in this crash may look slightly different
Tupolev Tu-154M
Operator:China Southwest Airlines
Registration: B-2622
MSN: 90A846
First flight: 1990
Total airframe hrs:14135
Engines: 3 Soloviev D-30KU-154-II
Crew:Fatalities: 11 / Occupants: 11
Passengers:Fatalities: 50 / Occupants: 50
Total:Fatalities: 61 / Occupants: 61
Aircraft damage: Destroyed
Aircraft fate: Written off (damaged beyond repair)
Location:Ruian (   China)
Phase: Approach (APR)
Nature:Domestic Scheduled Passenger
Departure airport:Chengdu Airport (CTU/ZUUU), China
Destination airport:Wenzhou Yongqiang Airport (WNZ/ZSWZ), China
China Southwest Airlines flight SZ4509, a Tupolev Tu-154M, departed Chengdu Airport in China at 14:35 hours on a domestic flight to Wenzhou. The en route altitude was 11400 meters.
At 16:02 hours, when the aircraft passed 9000 meters in the descent towards Wenzhou, the crew felt that the steering column was too far forward. The crew were puzzled by the control issue, especially at 16:26 hours when the steering column was fully forward. Yet, the aircraft was not in a nose-down attitude. The captain noted that the controls felt disconnected. At 16:29 the flight was cleared to descend from 1200 m to 700 m. When the flight crew selected the first stage of flaps, an angle-of-attack warning sounded in the cockpit. The aircraft entered a stall and began a steep descent until it impacted a farm field at Ruian.
Several farmers were injured by the flying debris.

Probable Cause:

PROBABLE CAUSE: A self-locking nut, other than castle nut with cotter pin as specified, had been installed at the bolt for connection between pull rod and bellcranck in the elevator control system. The nut screwed off, resulting in bolt loss, which led to the loss of pitch control.

Wrong installation of parts
Elevator issue
Loss of control

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photo of Tupolev-Tu-154M-B-2622
accident date: 24-02-1999
type: Tupolev Tu-154M
registration: B-2622

This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path.
Distance from Chengdu Airport to Wenzhou Yongqiang Airport as the crow flies is 1654 km (1034 miles).
Accident location: Exact; as reported in the official accident report.

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Tupolev Tu-154

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