Factual error: When Joe Patroni is attempting to move the stuck 707, Bakersfeld is standing beside his car watching, very close to the plane. Without some form of hearing protection, he would have been very quickly deafened by the noise - a 707 at takeoff thrust is incredibly loud. I once watched a 707 take off from about a half mile away and forgot to cover my ears - it was so loud it actually hurt.
Continuity mistake: Burt Lancaster is sitting in his car at the end, and he asks the tower if he can listen to the radio traffic for the incoming plane that's landing. The tower replies "Sure, it's on frequency 117.1". Burt then tunes the dial on his receiver to 171, not 117. 170 is blatantly written under the dial in bold type.
Other mistake: When the stricken airliner is on final approach for landing, both pilots stare intently out the windscreen, never so much as glancing down at the flight instruments. In an instrument landing the pilot must look continuously at the instruments until the copilot reports that the runway is in sight, as that is the only way he can follow the controller's instructions.
Revealing mistake: When the car enters the scene near the beginning of the movie where everyone is getting of the stuck aircraft, you can see the tire track in the snow where the vehicle is going to go. (00:07:50)
Factual error: In the scene where Joe Patroni is attempting to move the stuck 707, he pushes the throttles forward, problem is the throttles he is using are for a twin engine plane. The 707 has 4 throttle levers.
Continuity mistake: When arguing about the expansion of the airport with Ackerman, Mel steps behind a display model of the airport layout. We see him standing in one position for several seconds, but in the next shot his arms are positioned completely differently, and he is standing in a slightly different spot. (00:45:15)
Continuity mistake: When the bombed plane lands, the pilot pulls the throttle all the way back and is seen turning something off, but a few seconds later, his hand is again on the throttle, which is positioned halfway, as it used to be.
Other mistake: Early in the flight, one of the pilots explains to a flight attendant that regulations require that if either of the pilots leaves the cockpit, the remaining pilot must put on his oxygen mask until the other pilot returns (which the remaining pilot is shown doing). However when the bomb goes off with one of the pilots in the rear of the plane, they immediately switch to the cockpit and show the remaining pilot quickly putting on his oxygen mask (which he was not wearing) as he puts out the "Mayday" call.
Other mistake: When they are trying to put together the character of the potential bomber, when he bought insurance, the woman who took his details said she remembered him because he didn't seem to have much money for someone going to Europe, but the bomber had told her he had changed all his US money for Lira, and when she persisted, he said the money was all in big bills, and he had left his cheque book at home - so he did have money.