Air Bagan Flight 011

Investigation

On 26 December, Burmese authorities formed the Myanmar Accident Investigation Bureau. The team was headed by the Deputy Director General of the department, U Win Swe Tun, and consisted of four other members. On the same day, investigators managed to retrieve the aircraft's flight recorders from the wreckage. The team initially had planned to send the flight recorders to Singapore for analysis, however it was deemed impossible due to the poor condition of both recorders. The flight recorders were later sent to Australian Transport Safety Bureau for analysis.

Initial statements by the authorities suggested that the pilots mistook a road for the airport's runway in low visibility. Managing director of Air Bagan U Thet Htoo Htwe stated that the aircraft was airworthy and that both pilots had followed the standard operating procedures.

Cause of crash

During the approach to Heho, the crew elected to conduct a non-directional beacon (NDB) approach. As it was an NDB approach, the crew were required to pass the Heho NDB first and then turn right to a heading of 220. The crew later had to turn left to heading 010 to align with the runway. The flight recorder, however, showed that the crew turned prior to Heho's NDB and later had to correct their heading again to compensate for the premature turn.

Flight 011 later entered clouds, obstructing their previously established visual contact with the runway. The standard operating procedures from Air Bagan stated that a flight officer was not allowed to conduct a landing in inclement weather condition and should be assigned as the PNF to monitor the aircraft's instruments. As the visibility at the time was less than 3000 ft, the captain should have been at the controls instead of the first officer.

As Flight 011 reached the approach's minimum descent altitude (MDA) of 530 ft, which was the lowest permissible altitude if the crew did not have visual contact with the runway environment, the GPWS alert sounded. The warning was ignored as the crew were trying to locate the runway. The aircraft kept descending and the crew were still not able to obtain visual contact with the runway as the presence of fog had deteriorated the visibility. The captain called, "Not okay, altitude hold," instructing the first officer to press the altitude hold button so that the autopilot would maintain the aircraft's altitude.

Air Bagan's standard operating procedures (SOP) clearly stated that if an aircraft had passed the airport's minimum descent altitude in inclement weather condition, an approach must be aborted; thus, the crew should have flown the missed approach procedure. The crew, however, decided to press the altitude hold button, even though they were just about 100 ft above the ground. As the aircraft was already too low for a missed approach, it crashed onto the trees, separating the left wing.

The crew's situational awareness had deteriorated because of the high workload. Their lack of situational awareness probably had also been affected by their landing order. The presence of other aircraft behind Flight 011 led to the increase of the crew's workload. As the crew were pre-occupied with the landing, the captain couldn't address the flight officer on problems regarding the aircraft's position and rate of descent.

Conclusion

The final report concluded that the primary cause of the accident was the crew's decision to descend below the approach procedure's minimum descent altitude of 530 ft without having the runway in sight. At that point, the airline's standard operating procedure would have called for an aborted landing to be immediately initiated. The report cited as contributory factors the captain's inadequate risk assessment in designating the first officer as pilot flying for the approach in the given weather conditions, and an increased pressure on the flight crew to complete the landing due to the presence of other aircraft on approach to Heho at the time. Three safety recommendations were made.