On 11 December 1998 at approximately 17:54 hours Airbus A310-204, belonging to Thai Airways International Public Company Limited, of nationality and registration HS-TIA departed on a passenger scheduled flight TG261 en route on airways TG458 at flight level 310 from Bangkok international Airport to Surat Thani Airport. There were 14 crew and 132 passengers on board.
At 18:26 hours, the co-pilot first established contact with Surat Thani approach controller while the aircraft was 70 nautical miles away from Surat Thani Airport, Surat Thani approach controller gave instructions to execute Instrument approach procedures expecting the aid of VOR DME would be used. At runway 22 surface wind was calm with the visibility of 1.500 meters, light rain, and cloud base at 1800 meters feet. Temperature and dewpoint were 24/22 degrees Celsius respectively.
At 18:39 hours, the co-pilot contacted Surat Thani aerodrome controller and reported over the intermediate fix (IF). The controller informed him that the precision approach path indicators (PAPI) on the right side of runway 22 were unserviceable while the lefts were in use. The distance between each runway edge light was 120 metres. The distance between each runway end light and runway threshold light was 6 metres and the pilot should be aware that there was an obstacle at 400 metres from runway 22 threshold.
At 18:41 hours, the co-pilot reported passing final approach fix (FAF). The aerodrome controller informed the pilot that the aircraft was not in sight, yet ; however, it was clear to land on runway 22. The surface wind was blowing from 310 degrees at a velocity of 5 knots so the pilots should be careful of the slippery runway.
At 18:42 hours. the co-pilot reported that the runway was in sight and later on the aerodrome controller also had the aircraft in sight. The pilot decided to go-around. The aerodrome controller asked the pilot about the distance where the runway could be seen. The co-pilot replied that it could be seen at 3 nautical miles and requested for the second approach. The aerodrome controller requested for FAF report . Having been reported the FAF by the copilot, the aerodrome controller reported back that the aircraft could not be seen ; however , it was clear to land on runway 22. The aerodrome controller asked if the runway could be seen and received the ‘no’ reply from co-pilot. Then, the pilot made a go-around and requested for the third approach.
Aerodrome controller requested for FAF report from heading inbound and informed the pilot that the visibility was 1,000 meters with light rain at the airport. Also, it was clear to land on runway 22. The surface wind was blowing from 290 degrees at a velocity of 3 knots and the pilot should be careful with the slippery runway.
The co-pilot acknowledged at the time of 19:05:43 hours and after that the contact was lost.
At the beginning of the go-around, the pitch attitude was continuously increasing. […] the pitch attitude was 18° degrees […] 32°-33° degrees then increasing to 47°- 48° degrees […] the aircraft speed was less than 100 knots.
After careful consideration, the Aircraft Accident Investigation Committee of the Kingdom of Thailand ultimately came to the conclusion that the accident occurred because the aircraft entered into stall condition which might be caused by the followings:
- The pilot attempted to approach the airport in lower than minimum visibility with rain.
- The pilot could not maintain the VOR course as set forth in the approach chart . The aircraft flew left of VOR course on every approach.
- The pilots suffered from the accumulation of stress and were not aware of the situation until the aircraft entered into the upset condition.
- The pilots had not been informed of the document concerning the wide-body airplane upset recovery provided by AIRBUS Industries for using in pilot training.
- The lighting system and approach chart did not facilitate the low visibility approach.
- Stall warning and pitch trim systems might not fully function as described in the FCOM and AMM.