Plane crash in Nepal: An aviation expert’s theory of what caused a plane to crash out of the sky, killing 68 people

The tenuous atmosphere of a high-altitude runway and an optical illusion may have led to the plane crash in Nepal on Sunday that killed 68 people, with the fate of an Australian on board still unknown.

Aviation expert Professor Ron Bartsch said Yeti Airlines’ ATR 72 was plowed into the ground after apparently stalling in mid-air while attempting to land.

The aircraft was on final approach to Pokhara, on the edge of the Himalayas, 200 km west of the capital Kathmandu.

The video captured his final terrifying moments just as it landed at the city’s new airport, 822 m above sea level, after a 25-minute flight.

Life in the central resort of Pokhara has ground to a halt following the shocking crash today

It suddenly veered left and fell out of the sky with 72 people on board in the country’s worst air disaster in three decades.

Prof Bartsch believes the pilot may have lost control after an optical illusion made him believe he was flying faster than he actually was, causing the plane to stall.

Planes have to fly faster through the thinner air at higher altitudes to stay aloft – and the high-altitude runways in Nepal are notoriously difficult to navigate.

“The runways are very, very challenging, some of the most challenging in the world,” he told Nine’s Today Show on Monday.

Aviation expert Professor Ron Bartsch (pictured) says Yeti Airlines’ ATR 72 was plowed into the ground after apparently stalling in mid-air while attempting to land

“This terrain is terribly difficult to fly – very strong wind and high altitude. Planes don’t usually just fall out of the sky, especially modern planes.”

He ruled out any possibility of mechanical failure, instead suspecting that the pilot had brought the twin-engine propeller aircraft to a standstill in the difficult conditions and thin air.

“Planes need air to fly in, and the air is thinner there at about half a mile,” he said.

“But also the fact that when you’re skimming it can seem like you’re flying over the ground much faster than through the air.

“I would suspect that the plane went into an aerodynamic stall…that caused this.”

Footage appears to show the plane flying over houses in the city in central Nepal

Airport officials have confirmed that one Australian was among the 15 foreigners on board the domestic flight from Kathmandu, along with five Indians, four Russians, one Irish, two South Koreans, one French and one Argentine.

It is currently unknown if the Australian was killed or is one of the four survivors of the horrific crash. Daily Mail Australia has contacted the Department for Foreign Affairs and Trade for further details.

The harrowing video clip of the crash showed the plane making a sharp turn before falling to the ground seconds later with a loud bang, followed by screams.

Local television showed thick black smoke billowing from the crash site as rescue workers and crowds gathered around the plane’s wreckage.

A second clip appears to show the moment of the crash, broadcast on Facebook Live by one of its passengers.

The footage, said to have been taken by an Indian man named Sonu Jaiswal, shows smiling passengers as the plane flies over houses.

The Yeti Airlines logo can be seen over Mr Jaiswal’s shoulder and a Nepalese insurance advertisement can be seen on the airline’s tray.

The clip continues before the camera suddenly starts shaking and passengers scream. It then goes black with a loud pop before flames illuminate the frame.

The accuracy of the footage has not been independently confirmed by MailOnline, although the Times of India says it spoke to Mr Jaiswal’s cousin, who confirmed the 29-year-old was on board the plane.

It is reported that one of Mr Jaiswal’s companions, the three of whom were also Indian, shouted “It’s really fun” just before the crash.

Hundreds of onlookers rushed to the crash site, where the remains of the plane burst into flames

Rescue workers clambered around broken parts of the plane at the crash site on the hillside amid scorched ground, with television footage showing flames.

“The plane is on fire,” police officer Ajay KC said, adding that rescue workers had difficulty reaching the site in a ravine between two hills near the tourist town’s airport.

Pokhara is the gateway to the Annapurna Circuit, a popular trekking route in the Himalayas, and its new international airport opened two weeks ago.

The plane made contact with the airport from Seti Gorge at 10:50 a.m. local time, the aviation authority said in a statement, “then crashed.”

“Half of the plane is on a hill,” said Arun Tamu, a local resident who told Reuters he reached the site minutes after the plane crashed. “The other half fell into the gorge of the Seti River.”

Khum Bahadur Chhetri said he watched the plane approach from the roof of his house.

The plane, which is operated by domestic carrier Yeti Airlines (pictured), was 15 years old, according to flight tracking website FlightRadar24

“I saw the plane shaking, moving left and right, and then suddenly its nose dove and it fell into the ravine,” Chhetri told Reuters, adding that local residents took two passengers to a hospital.

There were 72 people, including two infants and four crew members, on the twin-engine ATR 72 plane operated by Yeti in Sunday’s disaster, airline spokesman Sudarshan Bartaula said.

According to flight tracking website FlightRadar24, the plane was 15 years old.

“We expect to recover more bodies,” said army spokesman Krishna Bhandari. “The plane broke into pieces.”

Russian Ambassador to Nepal Alexei Novikov confirmed the deaths of four Russians aboard the crashed plane.

Rescuers gather at the site of a plane crash in Pokhara today

Crowds gather at the crash site of a plane carrying 72 people in Pokhara, western Nepal

“Unfortunately, four citizens of the Russian Federation died. We are in constant contact with the Nepalese authorities and will provide all necessary assistance to the families of the dead Russians,” he said.

A South Korean embassy official said: “Two South Koreans are on the passenger list. We are trying to confirm if they were actually on board and their identity.’

Nepal’s Prime Minister Pushpa Kamal Dahal said he was “deeply saddened by the sad and tragic accident”.

Nepal Aviation Minister Jyotiraditya Scindia tweeted his condolences.

“The loss of life in a tragic plane crash in Nepal is extremely unfortunate. My thoughts and prayers are with the families of the bereaved,” the official said.

Locals watch the wreckage of a passenger plane in Pokhara

Chinese Ambassador to Nepal Chen Song also expressed his shock.

“At this difficult time our thoughts are with the people of Nepal. I would like to offer my deepest condolences to the victims and my sincere condolences to the bereaved,” he wrote.

The ATR72 is a widespread twin-engine turboprop aircraft manufactured by a joint venture between Airbus and Leonardo of Italy. Yeti Airlines has a fleet of six ATR72-500 aircraft, according to its website.

Prime Minister Dahal has called an emergency cabinet meeting after the plane crash, a government statement said.