Factual error: Sarah states that Namibia is on the Ivory Coast, while in fact, it is on the Skeleton Coast in southern Africa.
Other mistake: In the scene in which two Japanese Zero fighters bomb and strafe a PT base, shots of the attacking planes show them carrying no bombs. During the attack, they still drop around 20 bombs anyway, which is considerably more than the actual carrying capacity of the two planes.
Continuity mistake: When Halloran sets the barn on fire to distract the Germans he lights up some straw with a match. All of a sudden you see flames flickering up at various places which could not be caused by the fire he made. (01:32:45)
Continuity mistake: Following the shoot out between the Germans and the Greek partisans being aided by the English and American POW's, a German Officer leaps onto a motorbike and takes off into the narrow streets of the village. An American follows on a motorbike and sidecar. Towards the end of the chase the bikes 'jump' over a cart. The German Officer's cap flies off, yet as he tears into a courtyard he has his cap back on.
Continuity mistake: When Valiant flies down the gun barrel, he takes off his backpack and helmet, and he lays them down in the barrel before squeezing through the back of the gun. When he comes back out through the gun with the other birds, the backpack and helmet are not there.
Continuity mistake: In the scene where Tom Cruise show the map of Iran the folder disappears and then reappears on the desk.
Continuity mistake: When Mother and Mameha are waiting for the bid on Sayuri's mizuage, Mother's cigarette is short at one point, but becomes longer in the next shot.
Factual error: The daylight air-raid on the Norwegian Heavy Water plant in 1942 was done by Boeing B17G bombers, with the distinctive chin gun turrets. These planes did not come into service until 1944, when they were introduced to counter the head-on attacks by German fighters.
Revealing mistake: When the American pilots flying P-47 Thunderbolts are attacked by German fighters, the German planes are really American P-51 Mustangs painted with German markings.
Continuity mistake: The city railroad scenes were filmed in Spain, and many of the forest railroad scenes were filmed in Finland; in both of those countries, most of the railroad track is broad gauge (the rails are more than 5 feet apart). The plains and mountains railroad scenes were largely shot in Canada, where the rails are "standard gauge": 4' 8 & 1/2" apart. The rails can be seen to jump between far apart and closer together more than once as the movie progresses.
Factual error: This relates to the first movie with this title, the one with Jack Benny in it. About midway in the film there is a scene with Polish pilots in the RAF in a room. It cuts to a brief shot of airplanes flying which obviously purports to show the Polish pilots flying their airplanes. But, the airplanes shown are circa 1935 U. S. Army Air Corps Consolidated two place fighters, never used by the RAF and in fact totally obsolete and never used by any air force during WWII.
Audio problem: During the chase at the end of the movie, the police cars' tires squeal in the dirt.
Factual error: Fairfax was not present at the trial of Charles I, although his wife Anne was, (and was forcibly removed after telling the court what she thought of them).
Factual error: In the final football game scenes ( from about three-quarters of the way through the film or so) all the spectators are wearing 1970's clothes and have 1970's hairstyles.
Continuity mistake: Aaoron is buried in sand at the end to die. His arms are covered with it, then in the next shot, they are clean. He can't reach them to brush them off and no one else did.
Continuity mistake: When the protagonists are trying to get to the French embassy they pass a VW beetle whose windshield is smashed by a Red Khmer. The camera angle is not very helpful but if you look closely you see that the window is gone already, and the pieces flying over the hood are from the bit of glass that sticks in the frame. (00:56:50)
Continuity mistake: In the scene when the aeroplanes have the dogfight, the German plane is in fact a Spitfire and the two British planes are in fact two Messerschmidt 109's. In the making of the film in Spain, they needed one German and two British planes for the scene, so the only way they could do it was to put British markings on the two Spanish Airforce Me 109's, which they had more of than Spitfires.
Factual error: The song that Davy Crockett plays on the violin is 'The Mockingbird Quick-Step,' written in 1855, several decades after the events of this movie (and later used by the 'Three Stooges' as a theme song.).
Continuity mistake: The writing on Ghost's sword early in the film has the Turisas rune (representing TH in Thunder) near the hilt, but later not only is a different font used but now the Dagalas rune (representing the D in sword) is at the hilt.
Factual error: At the beginning of the film, just after the credits, there is a definition of the word 'army'. It is claimed to be from the 'Encyclopaedia Brittanica', an obvious spelling error - "Brittanica" should have one T and 2 N's.