Analysis of accident data of the last six decades of Nepal’s aviation history shows a pattern. But the tragic crash of the Yeti Airlines ATR72 in Pokhara on 15 January did not fit this template.
More than 90% of fatal crashes since 1962 can be classified as CFIT (Controlled Flight into Terrain) in which an airworthy aircraft collides with mountains hidden by clouds.
But Yeti Airlines flight YT691 was preparing to land in broad daylight, in good visibility and clear weather, at a brand new international airport with all modern navigational equipment.
After the last crash in June 2022 of a Tara Air Twin Otter on a flight from Jomsom to Pokhara, Nepali Times had mined data from multiple sources to try to get to the bottom of why Nepal has such a poor safety record.
Between 1962 and June 2022, there had already been 818 fatalities in 67 air crashes. Of the deaths, most were in accidents involving CFIT. Nearly all serious crashes in that period occurred on mountain routes, and most of them were during the monsoon months.
Very few of the crashes in the past 60 years were caused by mechanical failure, loss of control, or bird strikes. And there had been no fatal crashes at Tarai airports. (See map)
Although there have been quite a few CFIT crashes in Pokhara or between the tourist city and Jomsom, there had been only one fatal accident on a flight to Kathmandu — a Necon Air HS-748 that struck a telecom tower at the western edge of Kathmandu Valley in 1999, killing 15.
Experts describe Nepal as the most difficult country to fly in because of a combination of treacherous terrain and weather, as well as insufficient navigation aid to airports with short runways and lack of accurate local weather forecasting.
But weak regulatory oversight, commercial pressure, failure to follow procedures by flight crew have often been cited in previous air crash investigation reports as supplementary reasons in most accidents. These points were largely ignored, leading to a distressing repeat of deadly CFIT occurrences over the years.
Almost every past investigation blamed violation of the regulation of flying VFR (Visual Flying Rules) at all times in the mountains as the primary reason for crashes. Crew underestimated the severity of deteriorating weather en route or at the destination, and were often over-confident or did not comply with standard operating procedures. Inadequate crew training was also often cited.
But flying into a mountain in bad weather was not the reason for the YT691 disaster on Sunday, leading to the largest ever loss of life on a domestic flight in Nepal’s aviation history. And it happened at an international airport that had been inaugurated by Prime Minister Pushpa Kamal Dahal only two weeks previously.
The same captain and co-pilot had flown the same plane (9N-ANC) as YT672 from Kathmandu to Pokhara at 0850 that morning, making a straight-line approach to land on runway 30 from the east.
They flew the plane back to Kathmandu, where Yeti Airlines merged it with another flight that was not full. YT691 then took off from Kathmandu again at 1032, and had already got ATC clearance to land on runway 30 when the captain asked for runway 12 from the west. The controller complied because there was no other traffic, but did not ask for the reason, according to sources.
But while making the base to final turn over the old airport, the ATR72 stalled and crashed into the Semi Gorge, narrowly missing a residential area densely packed with houses.
Eyewitness videos show the plane in a nose-up attitude, flying very slow and low, and seemingly in a landing configuration without flaps deployed. The end was swift, a video live-streamed by an Indian tourist of the final moments shows that it took only a few seconds between when the plane began to roll to impact.
None of the 72 passengers and four crew are believed to have survived. Rescue efforts were hampered by gawkers and selfie takers, although there were heroic efforts by local youth to pull some passengers out of the flaming wreckage.
The actual reason for the crash will have to await analysis of the Flight Data Recorder (Black Box) and Cockpit Voice Recorder by an investigation committee that has been formed.
But it is clear from the videos that the plane stalled on the final turn. The question is why?
A plane suffers a wing stall when there is insufficient lift either due to multiple engine failure, steep bank turn or angle of attack and/or failure to maintain air speed. Captain Kamal KC was a veteran with nearly 22,000 hours, with much of it on BA Jetstreams and ATR72s.
Co-pilot Anju Khatiwada had logged 6,500 hours, and was sitting on the left cockpit seat on a final clearance flight to earn her captain’s wings, which she would have got upon landing YT691 that day.
Ironically, Khatiwada’s husband had died in a crash of a Yeti Airlines Twin Otter in Jumla in 2006, when that plane also stalled while making a tight turn on finals.
The Pokhara crash is expected to complicate Nepal’s effort to extricate itself from the European Union’s safety list which has banned Nepal’s carriers from flying to or through Europe since 2013. The EU wanted the Civil Aviation Authority of Nepal (CAAN) to be split into regulatory and operational agencies, and make several procedural reforms.
After a 2017 audit by the International Civil Aviation Organisation (ICAO) gave a passing score, CAAN officials had been optimistic that Nepal would be removed from the EU Aviation Safety Agency blacklist.
But the Tara Air crash in June 2022, and the Yeti Airlines disaster this week could delay European certification. Tara is a subsidiary of Yeti Airlines and the group’s founder, And Tshering Sherpa himself died in a crash in Taplejung in 2019 in one of his own helicopters, along with Tourism and Civil Aviation Minister Rabindra Adhikari.
Adhikari, who was also MP from Kaski, had been instrumental in expediting the delayed construction of Pokhara’s new airport that was inaugurated on 1 January this year, just two weeks before the tragic crash.
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