Corrected entry: At the end of the film when the planes begin landing there is no reason for the planes to deploy emergency chutes and send the passengers outside into the snow. All aircraft landed safely without incident. They were simply low on fuel. Planes only evacuate if there is impending danger to passengers by remaining on board.
Andy in Wasaga
3rd Sep 2013
Correction: There are plenty of reason to do so. (1) The planes were low on fuel and the landing area is a distance from the airport. So they might not have enough fuel to move back to the airport. (2) They are all now in deep snow. The planes might not be able to get out on their own power. (3) It is the middle of the night. The people on board wouldn't want to wait till they can get ladders out there.
XIII