Continuity mistake: In two spots in the movie, first with Thornton and the second time with both Thornton and Cusack they stood on the runway over the threshold markings and waited for a landing aircraft so they could feel the strength of a wake turbulence. On final approach the pilot would have seen him/them on the runway and called a missed approach and execute a go around. You just don't land when there is an obstruction on the runway, it makes a hell of a mess of the undercarriage...
Continuity mistake: The movie seems to make a big show about the controller (Thornton and Cusack) guiding aircraft within a couple hundred feet of each other. If the movie followed actual FAA rules of aircraft separation (I believe it's a half mile vertical and two miles horizontal or so, but certainly farther than was constantly depicted), then both of them would have been suspended or fired several times over before the end of the movie. And that isn't something that would be up to their supervisors.