Narrative:One-Two-Go Flight 269 departed Bangkok-Don Muang (DMK) at about 14:30 for a domestic service to Phuket (HKT).
The flight was conducted uneventfully and as the flight arrived in the Phuket area, the flight crew conducted the ILS runway 27 approach to the airport, with the first officer as the flying pilot. After the flight crew reported to Air Traffic Control (ATC) that they were “established [on the] localizer,” the crew that preceded the accident flight to the airport, reported weather information
that they encountered during their approach. This information included an airspeed gain and loss of 15 knots during the final portion of the approach and noted a "CB over the airport." The flight crew of OG269 acknowledged the transmission and they were cleared to land at 15:37, with a wind report of 240 degrees at 15 knots. One minute later, the controller issued another wind report,
"OTG269, strong wind 240 degrees 30 knots." The pilot of OTG269 acknowledged the report, and shortly after, inquired again about the wind condition. The tower responded "240 degrees 40 knots," and the pilot acknowledged the report.
Information obtained from the CVR and FDR indicated that the flight crew conducted the ILS approach with the airplane aligned just to the north of the runway 27 centerline.
Between 15:39:41 and 15:39:43, as the airplane was descending through 115 feet above threshold level, the airspeed dropped from 140 KCAS to 126 KCAS. At 15:39:43 the captain called for power, and the engine pressure ratio (EPR) subsequently increased toward 'go around thrust.' The EPR for both engines increased from about 1.16 to 2.0 in approximately three seconds and remained about 2.0 for the following 2 seconds, until about 15:39:48. Between 15:39:40 and 15:39:47, the pitch angle increased from 0 degrees to 5 degrees, and then decreased to about 2 degrees at 15:39:48.
Despite the increase of thrust and pitch, the airplane continued to descend until about 15:39:48, reaching an altitude of 48 feet above threshold level before starting to climb. However, the airspeed increased during this time, from 126 KCAS at 15:39:43 to
166 KCAS at 015:39:48. At 15:39:47, the crew received a "sink rate" warning, and at 15:39:48, as the airplane descended below 50 feet, the autothrottle system initiated an automatic reduction of all engine thrust. The engine EPR decreased from 2.0 (‘go around thrust’) at 15:39:48 to about 1.14 (‘idle thrust’) at 15:39:53.
At 15:39:49, the first officer called for a go-around, and the pitch of the airplane increased from about 2 degrees to about 12 degrees, as the airplane climbed. The thrust continued to decrease towards its ‘idle’ position, while the airspeed decreased from 165 KCAS to about 122 KCAS at 15:39:57.
At 15:39:50, the first officer transferred aircraft control to the captain as the thrust was reaching idle EPR. The EPR remained at the ‘idle’ level for about 13 seconds, as the airplane continued to climb to a maximum altitude of 262 feet at 15:40:01, and then started descend again. During this time, the landing gear was retracted, and the flaps were set to 15 degrees; however, the
takeoff/go-around (TO/GA) switch was never pressed.
The pitch angle decreased from 12 degrees to about 0 degrees, while the airspeed remained relatively constant at around 122 KCAS, with about +/- 4 knot excursions about this average.
At 15:40:06, a “don’t sink” warning sounded in the cockpit, as the airplane was descending through approximately 175 feet. The EPR began to increase again, reaching ‘go around thrust’ at 15:40:09; however, the altitude and pitch continued to decrease.
At 15:40:09, a “sink rate” warning, followed by a “pull up” warning sounded in the cockpit. During these warnings, the pitch began to increase from 0 degrees. The pitch increased to approximately 5 degrees over the next second, until the aircraft impacted the ground next to the runway at 15:40:11. The aircraft slid across a concrete ditch and burst into flames.
Probable Cause:PROBABLE CAUSES:
After thorough investigation, the AAIC determined that the probable causes of accident are as follows:
1. the flight crew did not follow the Standard Operating Procedure (SOP) of Stabilized Approach, Call Out, Go Around, and Emergency Situation as specified in the Airlines’ Flight Operation Manual (FOM).
2. the Take Off/ Go Around (TO/GA) switch was not pressed, resulting in the failure of increasing in airspeed and altitude during the go around. Also, there was no monitoring of the change in engine power and movement of throttle levers, especially during the emergency situation.
3. the flight crew co-ordination was insufficient and the flight crew had heavy workloads.
4. the weather condition changed suddenly over the airport vicinity.
5. the flight crew had accumulated stress, insufficient rest, and fatigue.
6. the transfer of aircraft control took place at a critical moment, during the go around.
|investigating agency: ||Aircraft Accident Investigation Committee of Thailand |
|number: ||Final report|
|download report: ||
Insufficient rest / fatigue
Loss of control
METAR Weather report:
08:35 UTC / 15:35 local time: SPECI 0835 UTC: 270/09KT 4000 +RA SCT015 BKN110 BKN300 26/24
Wind 270 degrees at 9 knots; visibility: 4000 m in heavy rain; scattered cloud layer at 1500 ft; broken cloud at 11000 feet and 30000 feet; Temperature 26deg C; Dew point 24deg C
08:45 UTC / 15:45 local time: SPECI 0845 UTC: 270/28KT 0800 +RA SCT015 BKN110 BKN300 25/22
Wind 270 degrees at 28 knots; visibility: 800 m in heavy rain; scattered cloud layer at 1500 ft; broken cloud at 11000 feet and 30000 feet; Temperature 25deg C; Dew point 22deg C
Follow-up / safety actions
|20 DEC 1983
|02 DEC 2001
|13 MAR 2007
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 Bangkok-Don Muang International Airport to Phuket International Airport as the crow flies is 688 km (430 miles).