A passenger plane crashed on landing at a remote airfield in Nepal's Everest region on Wednesday, killing 18 people most of whom were German tourists, Nepalese officials said.

The Yeti Airlines aircraft, flying from the capital Kathmandu to Lukla in eastern Nepal, burst into flames after crash-landing near the sloping runway under heavy cloud, witnesses reported.

Of the 19 people on board, 14 were foreigners and five were Nepalese, and only one — the Nepalese pilot of the Twin Otter plane — survived, airport official Mohan Adhikari said.

"There were 12 Germans and two Australians on the flight," said Adhikari.

Officials earlier said the passenger manifest listed two of the tourists as Swiss, but they were later confirmed as Australian.

Security staff and volunteers took two hours to extinguish the fire in the wreckage of the plane.

Hundreds of tourists and residents from Lukla, 140 kilometres northeast of Kathmandu, watched the recovery operation, many in tears.

"I saw the plane start its descent, then cloud came in and we heard a loud noise and saw flames," said Bijaya Pratap Singha, a tour manager.

"We ran down to the end of the runway and saw everything was scattered and the plane was on fire."

Local officials told reporters the crash had been due to heavy cloud.

Dozens of flights land everyday

When the weather is clear, dozens of flights land every day at Lukla's Tenzing-Hillary airport, a gateway to Nepal's Everest region used by trekkers and mountaineers.

The airport was renamed after Mount Everest's first conquerors, Sir Edmund Hillary and Tenzing Norgay, earlier this year.

Just 20 metres wide and 550 metres long, its runway perches on a hillside at an angle of around 11 degrees and were built using funds from Hillary's Himalayan Trust.

Fast-moving weather patterns at the tiny airport — which is 2757 metres above sea level — mean bad weather frequently halts operations.

"We are devastated to hear of this accident," Ang Tsering Sherpa, the president of the Union of Asian Alpine Associations, told AFP.

"In the season there are up to 50 flights per day into Lukla so the pilots are very used to landing there."

Flights from Kathmandu to Lukla take just over half an hour.

AFP