Corrected entry: The old U.S. 'S'-type submarine could never have been converted to resemble a German type VII or IX (Atlantic fleet boats) without drydocking and major work - which certainly could not have caught the crew by surprise.
Corrected entry: The depth the U-571 is depicted as achieving was beyond 'crush depth' even considering the 2.5 safety factor all u-boats were designed to. There is no way the boat would have survived that depth.
Correction: The max depth depicted on the gauge is just beyond 200 meters. The maximum depth of the VIIC U-boat (which U-571 was) is 220 meters.
Corrected entry: When the U-571 is being depth charged one of the men asks Chief if he has ever been depth charged before. He says "once, in World War I..." But during WWII they did not refer to the first world war as World War I. They still called it The Great War. It wasn't until after WWII that either war was referred to that way. (01:18:10)
Correction: It was commonly called "The Great War" or sometimes "the war to end all wars" until World War II, although the name "First World War" was coined as early as 1920 by Lt-Col à Court Repington in The First World War 1914-18.
Corrected entry: After the S-33 is torpedoed, Tyler and his men rig the U-571 for dive. Just before Wentz says "Opening midship valves; opening midship vents," someone else - I think it's the Chief - says "Opening ballast tanks." This makes no sense; the ballast tanks are the air tanks - you open them when you want to surface, not when you want to dive. (00:51:30)
Correction: Ballast tanks are opened so they can be filled with water to dive. The water is pumped out making the sub buoyant again to surface.
Correction: Actually the ballast tank vents are what are ordered to open to dive. These are deck level and as air escapes water is drawn in from the always open bottoms of the ballast tanks.
Corrected entry: Throughout this movie these guys were shooting off more rounds than Rambo. In an enclosed sub, wouldn't they be concerned with getting hit by their own bullets once they ricochet off the walls?
Correction: Sure they'd be concerned, but what's the difference if they get shot by their own bullets or German bullets? They're not going to run through the boat waiting to be shot, so it's an acceptable risk they are willing to take.
Corrected entry: Throughout the movie, when the sub is submerged, it show the submarine about 10 meters down, not 100, or 200 as the characters stated.
Correction: The shots of the sub are correct. The shots looking up at a vessel's props from only a few meters below the surface are of the Nazi destroyer, not the submarine.
Corrected entry: For the raid on U-571, Tyler chooses to dress as a German officer, thus making himself the most likely one of the boarding party to be addressed by the German crew, even though he speaks no German (which ultimately gave the deception away early). This tactical error is inexplicable, given that there were two fluent German speakers among the Americans.
Correction: As Tyler is noticeably older than other members of the crew, so it makes sense that he should be an officer. Besides, it wasn't his reluctance to talk that tipped the Germans off: one of the Germans saw Griggs pull out his machine gun, and that's what gave it away.
Corrected entry: Why does the German re-supply U-boat open fire on the disguised American sub when they are docked with U-571? The American Sub is disguised well enough to pass a visual inspection, and you'd think the Kriegsmarine sailors would be pleased to see some fellow Germans at sea. They certainly wouldn't simply open fire with torpedoes because they didn't recognise the other U-boat.
Correction: The German resupply sub was at periscope depth and must have been watching for a few minutes before opening fire. Seeing the boarding party from the American sub whip out machine guns and shoot the Germans on the U-571 was probably a big clue that they weren't all on the same side.
Corrected entry: The German commander is depicted eating a piece of fruit just prior to the depth charge attack against the U-571. No German commander would have done this. Food was strictly rationed and accounted for on the boat for various reasons - not the least of which was making sure there was enough to last for the duration of the patrol. If men were allowed to grab food and eat it as it suited them there would be no way to control its consumption. No commander would have set such a dangerous precedent by such wanton consumption.
Correction: He could have saved it from his last meal. I know when I was in boot camp, I would often save an apple or orange to eat a little later.
Corrected entry: A grenade exploding in the control room of a U-boat would have destroyed and damaged many important controls and indicators - yet no damage appears to any of the controls in later shots.
Correction: It was a tear gas grenade. They are designed more like a can of hair spray, they have no explosive, just compressed propellants to discharge the gas.
Corrected entry: In the scene on the dock where the mess steward sees the lieutenant struggling to light a cigarette, he comes over and offers his lighter. The officer was actually facing away from the sailor, so how could the mess man even know the lieutenant could not light the cigarette?
Correction: If you look closely, the mess steward is not standing with his back to Tyler. He is walking by with Tyler on his left side. He glances over and sees Tyler having trouble lighting his cigarette.
Corrected entry: Non-whites were not allowed in the "Submarine Navy" until the next decade.
Correction: Black men were allowed on submarines as cooks or stewards in WWII. In a sub everyone has to know two or three jobs. Often this was the only way for a black man to learn technical jobs like sonar or navigator.
Corrected entry: The sailors - rightly so - become very frightened when the long range plane spots them. However no sub captain in his right mind would stay on the surface if he heard the sound of an aircraft - it was one of the lookout's primary tasks: alert the captain if they heard propellers, and prepare to dive.
Correction: U-571 was badly damaged. She might not be able to submerge quickly or for long periods, no matter what the lookout saw or heard.
Corrected entry: When the US commandos are about to board U-571, we see a cocked MP-40 gun hanging from an officer's neck, which is hidden in his jacket. You don't just let those guns hang like that, or it'll fire off at the slightest shock. Not a very smart thing to do in a stormy sea.
Correction: The MP38 (which is identical to the MP40) had that defect. It was corrected in the MP40.
Corrected entry: Enlisted submariners of that time period wore silver dolphins on their dress white uniforms (like the officers wore their gold ones in the movie) and not black embroidered dolphins on their sleeves.
Correction: WWII enlisted submariners did wear embroidered dolphins in their sleeves. In 1947 enlisted men were authorized to wear their dolphins on their breast. In 1950, the embroidered patch was replaced by a silver pin.
Corrected entry: When U-571 is supposedly at 200+ meters below the surface, the depth charges seem to be getting dropped into the water, as if they were 5 meters up, not sinking in the water as if they were 200+ meters down.
Correction: The shot of the depth charges DOES show them being dropped in at about 5 metres deep, because the view is from the back of the destroyer just below the waterline, not the back of the sub.
Corrected entry: In the scene in the captain's cabin where Bill Paxton is explaining to Matthew McConaughey why he didn't recommend him for a promotion, the words on the sheets on his bed are reversed.
Correction: Yes, the words are reversed, however in the DVD version the director says this was done on purpose since that's the way the sailors made their beds.
Corrected entry: Once the survivors are in the U-boat the black character mans the controls. He's the cook, how does he now how to operate the controls?
Correction: Every man on the submarine learns the controls since they're out at sea for so long and it is so crucial to be able to run the submarine at all times.
Corrected entry: When the German electrician is tapping that Morse code message, how can the guy who says what it is (who doesn't speak German), understand what he is saying. The message should be "Ich bin U-571. Zerstören Sie mich," since he can't speak any English. (He didn't answer the questions because of that.)
Correction: It was translated by the young sailor who could speak fluent German.
Corrected entry: Anybody with any mechanical knowledge seems to have been killed in the fire in the engine room, on a sub on patrol there would have been at least two watches, one working, one resting and both watches would not have been in the engine room at once.
Correction: When the alarms start ringing and the engine room is sustaining heavy damage, all the mechanics would have rushed in to fix it.
Correction: It wouldn't have been difficult to make the S boat look like the U boat from the waterline up. The above-water profiles are very similar and would only require a few modifications. Throw enough metal workers at the task and it could be done in a night, easily. The S boat captain makes a point of running the disguised S boat low in the water to hide more of it's profile.