Narrative:Yeti Airlines Twin Otter 9N-AFE took off at 12:43 from Nepalgunj (KEP) bound for Bajura Airport (BJU) located in far western Nepal. It carried 1350 kg of rice. After reporting 20 miles at 8500 ft to Nepalgunj tower the flight was then instructed to report Virgin pass, a compulsory reporting point en-route to Bajura and other far western airports. The Nepalgunj tower also provided 9N-AFE with wind information at Bajura as westerly ranging from 10 to 15 knots.
Another Yeti Airlines aircraft 9N-AEV also had taken off from Nepalgunj after 9N-AFE and was in contact with 9N-AFE over radio. The crew of 9N-AEV radioed that it had communicated with Bajura and had been informed that the wind speed had increased with a gusting tendency and could reach 20 knots.
At 13:02, 9N-AEV had reached 30 DME from Nepalgunj and radioed AFE that wind at Bajura had increased to 18 knots and stated that they would divert back to Nepalgunj.
At 13:04 9N-AFE established radio contact with Bajura tower and received the latest wind information as- "wind continuously westerly at 08/18 knots." The pilot then contacted Bajura and stated that they had arrived west of Virgin Pass and were about to enter the valley. This communication was repeated a couple of times as it was not
intelligible to Bajura over HF radio. At 13:08 Bajura reported the latest wind information as 25 knots.
The crew subsequently reported entering valley at 5000 ft and were given the wind then as 18 knots and instructed to report final. At 13:18 9N-AFE was given wind information as 18 knots and told that the runway was clear. On finals the aircraft's left main landing gear struck the 4 ft high barbed fencing and tore along some length of the barbed wires and simultaneously bounced off the edge of a culvert inside the fencing with a slight left bank and glided to a stop about 900 feet from the threshold.
PROBABLE CAUSE: "The Investigation Committee determines that the probable cause of the accident was flight-crew's continued flight to at Bajura, with the intention of landing, in excessively gusting winds. The resulting control difficulties in maintaining the desired flight path during landing were exacerbated by the illusion (during period of high crew workload) resulting from the up-sloped runway at Bajura caused the aircraft to descend below the desired flight path and contact terrain. The contributory causes to the accident were virtually non-existent operational control of STOL flights by Yeti Airlines, insufficiency of CRM trainings at Yeti Airlines and lack of adequate oversight of Yeti Airlines by CAAN Flight Operations Division."