What happened
A scheduled flight from Istanbul arrived at Tribhuvan International Airport (TIA) in Kathmandu on March 3. The aircraft, carrying 224 passengers and 11 crew members, initially encountered difficulties contacting Kathmandu Control due to the facility not being operational during its descent. After establishing contact with Kathmandu Approach, the flight was instructed to hold over Parsa due to low visibility of 100 meters.
Following a period of holding and an initial missed approach caused by a lack of visual reference, the crew decided to continue a second RNAV (RNP) AR approach for runway 02. During the final stages of the descent, the flight crew confirmed they could not see the runway, yet they continued the approach. At approximately 783 feet AGL, the crew inquired about the status of the approach lights, which the tower confirmed were at full intensity.
The aircraft's autopilots remained engaged until just 14 feet AGL, at which point they were disconnected for a manual flare attempt. The landing was unstable; the aircraft touched down with a nose-up pitch of only 1.8 degrees and drifted left of the centerline. The left main gear landed off the paved surface, causing the aircraft to cross taxiways E and D before coming to a stop on the grass between taxiway D and C. While there were no fatalities, the aircraft sustained damage that rendered it beyond repair. The crew requested medical and fire assistance, and passengers were evacuated via stairs rather than emergency slides.
Findings
The investigation identified that the primary cause was the decision of the flight crew to continue the approach and landing below established minima without adequate visual reference, failing to execute a missed approach as required.
Several contributing factors were noted:
- The crew's focus on completing the landing at Kathmandu may have led to operational errors.
- Inaccurate threshold coordinates had been uploaded into the aircraft's FMGS navigation database.
- A lack of updated ATIS information was available to the crew due to equipment issues.
- Weather conditions deteriorated due to moving fog, which was not adequately communicated by meteorological services or air traffic control.
- The flight crew did not strictly adhere to standard operating procedures or the published RNAV (RNP) approach protocols.