Continuity mistake: During the early part of the movie, there are a number of references to the Blackhawk crew, yet the wreckage is that of a Huey.
Factual error: The German fighters depicted in the film are Messerchmitt Bf 109 G-6s, and every single one of them is using the Rüstsatz VI gun pod, that is, 2 extra 20mm Mg 151 cannons. The Luftwaffe only equipped their Bf 109s with the gun pods when they were going to intercept bombers. In this movie, even on the fighter vs fighter missions, they have these gun pods, which is inaccurate, because the gun pods dramatically reduced the turning performance of the Bf 109s.
Factual error: During the battle at the Marshalls-Gilberts, the movie shows mountainous terrain. The real Marshalls and Gilberts are atolls with very little terrain.
Factual error: When Patton orders his driver to drive to the Carthaginian battlefield he addresses him as "sergeant". He is, however, wearing corporal's chevrons. A famous stickler for discipline and ceremonial, Patton is not likely to have made a mistake like this.
Factual error: Most of the parachutes are PX type. These came out in the 1960s. They only used X type during the war - only a few of those are seen in the film. (00:07:00)
Factual error: During the plane ride into France, the Paratroopers are holding/carrying their weapons by their sides. In reality, their weapons (M1 Garands, B.A.R.s, etc.) would be carried in special "bags" strapped to their parachute harness. This not only protected their weapons, but also secured them to their person.
Character mistake: At the beginning of the movie, the German sub gets surprised and severely damaged by a destroyer. The sonar man first notices the enemy destroyer approaching, but only a short time before the destroyer is already literally on top of the sub. German sonar at the time had the capacity to detect ships up to more than 7 miles away, so the sonar man really had to be asleep at his sonar station not to notice the destroyer approaching. (00:03:40)
Suggested correction: He was in the sound room, not running sonar...given they were attacking a convoy, they wouldn't be running soar as that could be picked up by other ships.
Continuity mistake: John's staff sergeant military shoulder epaulet markings become upside down in the scene when he and Savannah are having dinner at her house when he comes to see her after his dad died. In a later shot shortly after, they are correct.
Visible crew/equipment: As Achilles' ship nears the Trojan shores, Agamemnon snidely asks, "What's the fool doing? He's going to take the beach of Troy with fifty men?" At the start of the next shot, as the camera begins to pan down, on the far right, just beside a person's (who is dressed in blue) head is a metal bullhorn (ie. used to give instructions to cast/crew, and which definitely doesn't belong in this time period). (00:36:35)
Factual error: The final scene of the movie has Col. Kirby and the little Vietnamese boy supposedly on the beach at Da Nang, Vietnam. Kirby is saying, "The future of 'nam is you, kid", and the camera pans out to the sea and the sun is going down. The sun's sinking in the east...
Suggested correction: Nowhere in the film are we told where in Vietnam the Green Beret base is, just that it is in South Vietnam (of course). South Vietnam has a Western coast, along the Gulf of Thailand, along which anyone can watch the sun set over the sea.
Around the 18:00 - 18:30 mark a character welcomes John Wayne to Da Nang. This base is returned to throughout the film, including the infamous sun setting in the east scene. Da Nang's beaches face to the Northeast. Only when you get south of Nha Trang does the Vietnamese coast begin to offer a south to southwest horizon on the ocean.
Continuity mistake: The scene where they are looking for Ryan's dog tag. Doc comments they are laughing in front of all the guys walking by. One of the soldiers looks like Sal Mineo. Frustrated, Tom Hanks walks into the line of soldiers and civilians and starts asking if anybody has seen or knows James Ryan. The same Sal Mineo lookalike walks by him again. (01:15:10)
Continuity mistake: When Rambo crashes through the road block in the army truck it's still daylight outside but when he's approaching the gas station it's nighttime. How could so much time pass when he was within minutes of town when he went through the road block?
Continuity mistake: A group of Marines approaches a minefield and one of them falls with his back on a mine. The explosion throws him in the air and you can see his uninjured back. Not even his shirt got a scratch. (01:46:50)
Revealing mistake: When the 54th Mass. marches past a liberated plantation some black children wave them on. One of them is wearing a digital wristwatch.
Factual error: If Owen Wilson is under a dead body, how could any thermal radiation leak through the cold dead body covering him so the satellite (plus the Admiral and aides) could see him the whole time? (00:54:10)
Factual error: After the birth of the baby, James Stewart and "Doc" Witherspoon are discussing the course of the war. "Doc" relates that he has always lived in Virginia and that his son died at Gettysburg at Little Round Top. No Virginia regiments fought at Little Round Top - only Alabama, Texas, Georgia, and Arkansas regiments.
Factual error: Near the beginning of the film before James McAvoy heads up to the house for the evening meal, he is seen looking up through a skylight when a Lancaster bomber slowly flies overhead. At the time it was was supposed to be 1935. The Lancaster bomber did not fly until the beginning of 1941. Can't be an Avro Manchester either, they only had two engines and first flew in 1939.
Continuity mistake: When the Nazi SS guard puts a pistol to Rutger Hauer's head, it's a Luger, but when the guard turns around, he's holding a Walther P38.
Visible crew/equipment: In the fight scene on the stairs near the end of the movie, the camera shot looks up and there is a security camera mounted up in the corner. (01:29:40)
Continuity mistake: In a major fight scene two soldiers on opposite sides are jumping and spinning and tapping each other on the head with their swords.