Deliberate mistake: At the beginning of the movie Mr. Coates tells his wife that he will be gone "all of three months, maybe four." The first time we see Bud and Elizabeth Searcy she tells Travis that her dog is pregnant and that Old Yeller is the father. We then see her dog that does not look very pregnant. The next time we see Elizabeth she presents Travis with one of the pups. The problem is that the pup that was supposedly just born is about 4 months old.
Revealing mistake: Allison is wounded by a grenade fragment while disabling the Japanese 105's. But when his bloody shoulder is first seen, the blood stain is visibly too bright for real blood.
Continuity mistake: At the start of the film when Tom is doing his trial run, he is forced off the road to avoid crashing into two oncoming trucks, driven by Johnny and Red. His truck has the number thirteen number board on the front, which isn't on it during any other time during the trial run, although it's on the truck for the rest of the film.
Factual error: When the UBoat changes course, Andrews, operating the radar repeater, is immediately able to provide the bridge with the target's new course and speed. This would be impossible without extensive calculations and at least range and bearing plots once the target has steadied up on the new course, either figured on the scope screen or on a maneuvering board. One must remember that both vessels' courses and speeds must be taken into account when making computations, and the relative direction of a target's travel most often is not its true course.
Factual error: As the movie opens, the submarine is dispatching frogmen to acquire Japanese mines that are sonar-proof. The problem with this is that in order to locate mines by sonar, either the mines must make noises to be picked up by passive hydrophones, or the submarine has to start pinging with active sonar. Doing this makes the submarine vulnerable to any enemy listening in. I can't imagine a submarine venturing into a mined strait, announcing to one and all, "Here I am"..
Factual error: While flying across the U.S. before the Atlantic attempt Stewart lands and exits the plane. While doing a quick inspection of the airframe he approaches the engine and puts his hand on one of the radial engines cylinders which would have still been several hundred degrees, so should have resulted in a serious burn.Robert Alan Sronce
Continuity mistake: According to one of the characters, the firing squad is drawn from the 3rd Battalion of the 701st Infantry Regiment, the same regiment as most of the other characters. However, all the members of the firing squad (except the officer and sergeant, who are credited characters seen elsewhere in the film) have "710" on their collar patches. This can be seen when the sergeant, who has "701" on his collar patches, is briefing them.Necrothesp