Background and Flight
A scheduled international flight departed from Kathmandu-Gaucher Airport at 1221 local time, bound for New Delhi. The aircraft carried 4 crew members and 6 passengers. No weather forecast was available before takeoff; the pilot was expected to receive a forecast from New Delhi en route. The flight was cleared to proceed direct to New Delhi, cruising at 8,500 feet.
Communications
At 1302 local time, the flight reported to Calcutta Flight Information Centre (FIC) that it was 100 miles out from its destination at 8,500 feet. A subsequent transmission at 1315 local time indicated its position as '83° East at 8,500 feet'. No further communications were received from the flight. Ground stations attempted to re-establish contact but were unsuccessful.
Search and Wreckage
Search and rescue operations commenced on 2 August. On 9 August, the wreckage of the aircraft was located on a mountain top at an elevation of 11,200 feet. All ten occupants, including the Indian ambassador to Nepal, were killed in the accident.
Probable Cause
The official investigation determined the probable cause to be: 'The drifting of the aircraft to the north of its track, towards high mountainous terrain, under instrument meteorological conditions.'