Lukla has a reputation among climbers for being the world's scariest airport; the planes that transport climbers are quite small.
"Imagine a metal tube of human sardines flying through the air," Mark Horrell, Everest climber and the author of the book "Seven Steps from Snowdon to Everest," wrote in his blog. "Sixteen people are crammed tightly together inside with their thighs pressed up against their chests and modestly full day packs balanced on top of their knees."
Horrell, who has made the trip to Lukla seven times, described one accident in 2008 when a pilot misjudged the landing.
"The plane burst into flames, killing everyone on board except the pilot, who was the only one able to escape from the fireball," he wrote.