Plot hole: Jennifer and the Captain exit the plane to give each other the final kiss, and the next shot shows them outside. But that's absurd, since there's no staircase next to the plane for them to get down.
Plot hole: The young man goes through security check and it beeps constantly when he passes by, allowing for the baddie to sort it out easily while carrying a gun. These systems only beep once, but, in any case, cops stop passengers from walking by when the systems beeps.