Continuity mistake: When Grant goes down to the main cabin and is looking around for the sleeper, the fringe of his hair goes from up and pushed back to all hanging down without him touching it.
Continuity mistake: Near the end of the movie, when Grant takes control of the airplane and lands on his second try, you can see the inner engine on the left wing (right to us) fall off and catch fire after impacting with the smaller parked planes. In the next shot, which happens quickly, you can see the engine is still in place and not damaged at all. In the next shot, it's gone again and the wing is on fire where the engine was.
Continuity mistake: When the girl goes down in the plane's elevator, you can clearly see the phone to her left (our right) has no light. In the later parts of the movie the phone becomes a very significant tool and now has a light on it. (00:12:03)