Accident A310 near Kathmandu

The Airbus A310-304 (registration number HS-TID, serial 438) made its first flight on October 2, 1987, and bore the flight number F-WWCE for the test period. On November 25 of the same year, it was sold to Wardair Canada , where it received the C-FGWD w / n and the name G. Levine Leigh . On January 15, 1990, Wardair Canada was acquired by Canadian Airlines International, and the C-FGWD went into the fleet last. On May 9 of the same year, the liner was acquired by Thai Airways International , in which it received the HS-TID tail number and the name Buriram . It is equipped with two General Electric CF6-80C2A2 turbofan engines ^{[2] [3]} .

The crew of flight TG-311 was as follows:

• The aircraft commander (FAC) is the 41-year-old Prida Suttimai.
• The co - pilot is the 52-year-old Phunthat Bunyayej.

In the cabin, 12 cabin crew worked.

In total, there were 113 people on board the aircraft - 14 crew members and 99 passengers ^[4] .

Flight TG-311 departed from Bangkok at 10:30 NST and headed for Kathmandu (estimated arrival time is 12:55 NST). Most of the flight took place without significant comments.

Closer to 12:40, flight 311 began to land at Runway No. 02 at Tribhuvan Airport . In connection with the rainy season ^{[4], the} approach was performed using instruments . The liner passed the Sierra radio beacon , after which the crew began to release the flaps and found that they did not work (according to the rules, landing at Tribhuvan Mountain Airport should be done with the flaps fully extended). The crew warned the dispatcher about the flap malfunction, after which 21 seconds after the first attempt and 21 nautical miles (38.8 km) from the radio beacon, Kathmandu was able to eliminate the flap malfunction. Due to the high altitude, requiring a steeper decline, the pilots decided to leave for the second round ^[1] .

The crew told the dispatcher that they intend to make a second approach, and are requesting permission to make a left turn to Romeo's point 41 miles (65.9 kilometers) south-south-west (azimuth 202 °) of Kathmandu beacon. But Tribhuvan Airport at that time was not equipped with a radar, and the dispatcher on duty at that time had only 2 months of work experience. At the request of the crew, the dispatcher said that landing on the strip No. 02 from the Sierra, which is 16 miles (25.7 kilometers) behind the beacon, is allowed. The crew replied that they could not land now and once again requested permission to turn left to Romeo for a second call. After a second request, the crew, flying at 025 ° at 7 miles (11.2 kilometers) from the Kathmandu radio beacon, began without a permission of the dispatcher to perform a right turn with simultaneous climb from FL105 (3200 meters) to FL180 (5486 meters). The crew informed the dispatcher that they had begun to climb, in response to which the dispatcher demanded to report the removal of 16 miles (25.7 kilometers) to complete the Sierra approach, maintain a height of FL115 (3505 meters), the minimum safe in the area south of the airport, and switch to communication with the dispatch center ^[1] .

The crew performed a 360 ° turn with a decrease to the indicated height, briefly stopping at the courses 045 ° and 340 °, after which it again took the course 025 °. At 5 miles (8 kilometers) southwest of the Kathmandu beacon, the crew reported to the dispatcher that they were flying at 025 ° and would like to return to Romeo for a second call, as they had technical problems with the flight. The dispatcher was allowed to follow to Romeo (later, as it was established from the recording of the voice recorder , the crew at that time had difficulties with the flight control system when indicating the route to Romeo's point, as well as with some other tasks). As a result, flight 311 continued heading north at 025 ° for another 16 miles (25.7 kilometers), after which the course changed slightly to the left by 005 °. A minute later, the dangerous ground proximity warning system (GPWS) unexpectedly worked, which issued voice messages about proximity to the ground and the need to start climbing. These messages sounded for about 16 seconds, but the crew did not react to them at first, considering them false. Only at the last moment the engines were switched to take-off mode, but it was already too late. At 12:45 NST, 25 miles (40 kilometers) northeast (azimuth 015 °) of the Kathmandu beacon, the TG-311 crashed into a mountain in the Langtang area at an altitude of 3505 meters above sea level and completely collapsed. All 113 people on board died ^[1] .

The crash of flight TG-311 was the first incident involving Airbus A310 (apart from the attempted hijacking of A310 by Singapore Airlines on July 31, 1991 , when all 4 hijackers were killed) and in 2019 it takes 4th place among all A310 plane crashes ^{[5 ]} . It is also the first major aviation disaster in Nepal , but after only 59 days it was surpassed by the disaster of the Pakistani A300 , in which 167 people died ^[6] .

On the same day as the crash of A310 Thai Airways International, a Yak-42 airliner of the Chinese airline China General Aviation crashed near Kathmandu in Nanjing ( China ), resulting in 108 deaths from 126 people on board ^[4] .

According to the results of the investigation conducted by the Nepalese commission, the cause of the TG-311 crash was the crew preserving the flight path in the north instead of turning south towards Romeo point and the inefficient radio communication between the control center and the flight crew of the TG-311 flight, which caused the flight It was carried out in the wrong direction, while the crew did not report on the bearing of the radio beacon (VOR), and the dispatcher did not request it, as a result of which the location of the aircraft was not controlled ^[1] .

The creation of a catastrophic situation was facilitated by such factors as:

• Incorrect display of the Romeo point on the navigation charts used by the crew;
• short flap failure, forcing to interrupt the initial approach;
• difficulties due to language problems during negotiations between the Thai crew and the Nepalese dispatcher, which was facilitated by the small experience of the air traffic controller, which led to insufficient discussion of the obvious unresolved problems ^[1] .

In the recommendations, the Nepalese commission pointed out the need to notify manufacturers of hazardous proximity systems (GPWS) and flight control systems (FMS) about aspects of this disaster, and operators of aircraft equipped with FMS and training centers should take FMS more seriously ^[1] .

• Some fragments of the aircraft have been preserved and can still be seen in the Langtang area.
• After the crash, in respect to the dead passengers and crew, Thai Airways International changed its Bangkok – Kathmandu flight number to TG-319 (return - TG-320) and, according to early 2014 , it is operated by Boeing 777 aircraft ^[7] .
• One of the dead passengers on TG-311 was Duncan Norrie, 34-year-old son of Bill Norry , Mayor of Winnipeg ^[8] . In memory of him in Winnipeg, one of the streets was named after him - Duncan Norrie drive.

The crash of Flight 311 is shown in season 17 of the Canadian documentary television series Investigation of Air Crash in the Lost Aircraft series.

• Accident Yak-42 in Nanjing ( China , 107 dead) - occurred on the same day