Investigation Summary
The accident occurred as the remnants of Typhoon Nari affected southern Laos, creating poor visibility and turbulent conditions. The crew was cleared for a VOR-DME approach to runway 15, which had a minimum descent altitude (MDA) of 990 feet. However, the crew incorrectly set the altitude preselect to 600 feet, possibly influenced by an incorrect figure of 645 feet on their Jeppesen chart. When they reached 600 feet without visual contact with the runway, they initiated a go-around. Because the altitude select was still at 600 feet, the Flight Director (FD) immediately entered altitude capture mode rather than providing climb guidance. The pilot flying (PF) initiated a right turn while the aircraft was still at a very low altitude, eventually descending to just 60 feet above the ground. A series of EGPWS warnings prompted the PF to pull back sharply, reaching a pitch of 33 degrees and an altitude of 1,750 feet. During this maneuver, the PF likely suffered a somatogravic illusion, perceiving the aircraft was falling backward. The crew then pushed the nose down, and the aircraft descended until it struck trees and the riverbank, plunging into the Mekong River.
Final Conclusions
The Lao Department of Civil Aviation concluded the primary cause was the flight crew's failure to properly execute the published missed approach procedure. Contributing factors included the decision to continue the approach below minima, the incorrect setting of the altitude preselect window, inadequate monitoring of flight parameters by the Pilot Monitoring (who was focused on flap configuration), and poor crew coordination. The investigation also highlighted the role of the aircraft's automation logic, where the Flight Director provided misleading cues because the selected altitude was lower than the aircraft's current altitude during the go-around attempt.
Photographic Evidence (1)
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
57-year-old Cambodian national, former air force pilot.
First Officer
22-year-old Laotian national.
Systems & Failure Modes
Flight Director (FD)
The FD provided misleading horizontal bar readings because the altitude preselect (ALT SEL) was set to 600 feet, which was below the aircraft's altitude during the go-around.
EGPWS
The Enhanced Ground Proximity Warning System issued multiple alerts as the aircraft descended to within 60 feet of the terrain during the botched go-around.
Altitude Preselect (ALT SEL)
The crew incorrectly set this to 600 feet instead of the missed approach altitude, causing the automation to capture a low altitude instead of climbing.
Interesting Facts
- 01The aircraft was nearly new, having been delivered to Lao Airlines only seven months prior to the accident.
- 02Initial recovery of the black boxes and victims was performed by a volunteer team of 11 technicians from a local hydroelectric dam; they were later joined by 50 professional divers from Thailand.
- 03The flight crew consisted of a highly experienced Cambodian captain and a young Laotian first officer with only 400 total flight hours.
- 04Victims were found as far as 19 kilometers downstream due to the fast-moving current of the Mekong River.
- 05The investigation was assisted by the French BEA and the aircraft manufacturer, ATR.
Safety Actions & Advisories
Pilot Training Enhancement
The investigation recommended increased emphasis on Crew Resource Management (CRM) and specific training for missed approach procedures in the ATR 72-600, particularly regarding automation logic.
Approach Chart Review
Authorities called for a review of navigational charts to ensure minimum descent altitudes and approach heights are accurately published and consistent across all providers.