Factual error: Klink and Hogan sit behind each other in the P-51 they try to steal. The P-51 is a single-seat airplane, the only twin-seat P-51 are trainers. A trainer would not be at the flight line with the regular airplanes, and if a trainer would actually scramble with the others, it would at least arouse suspicion.
Continuity mistake: When Klink and Hogan are looking at the Mustangs, Hogan has just sipped his coffee and holding the mug at chest level, at the top button of his coat. When the shot changes, he's holding it waist high. Also, the flight line full of planes is a grainy black-and-white projection super imposed in the shot of the window.