Continuity mistake: In the airfield, while Helena and Teddy are hiding behind some barrels, there's a man dressed in brown clothes (clearly not Indy as he's still on the ground) in the background standing behind Voller. This man disappears in the next shot. (01:59:00)
Continuity mistake: Klaber speaks to Voller in German, and then turns and reaches out to grab Indy (all this between the soldiers). But in the next shot, when Klaber grabs Indy, both Americans are now in the cabin. (02:00:02)
Continuity mistake: When Helena says "Guten Tag meine freunden", Klaber can be spotted in the background at the cabin already shooting with the machine gun. In a few shots later, he's just arrived at the cabin, holding the weapon, and repeats the action. (02:09:48)
Other mistake: Towards the start of the film, at the end of the train crash on the viaduct, time seems distorted. By the time it's taken Indy to wade out of the river and walk up its bank, magically a troop of British soldiers appear from nowhere, having entirely and instantly overrun a train full of Nazis? (02:16:01 - 02:16:35)
Continuity mistake: At the start of the film, towards the end of the steam train roof battle, as Indy jumps from the train (200+ feet into the rocky shallow looking part of a river), it's still fairly dark in the early hours of the morning. As he surfaces seconds later, it's considerably brighter. Then, as he walks up the river bank, morning is well broken into much brighter light. Assuming the scene is set around March/April 1945, sunrise in the Alps is unlikely to occur so rapidly. (02:16:01 - 02:16:35)
Continuity mistake: Helena places her mug on the upper middle part of a magazine, where a greenish band with the title is. A shot later, the mug has moved to the left edge of the magazine. (02:19:15)
Plot hole: At the start of the film, a young Jürgen Voller gets hit square in the face, at high speed, by trackside equipment and gets knocked off the train. But somehow, he isn't killed and survives without so much as a scar on his face.
Continuity mistake: When the villains are following Indy through the caves, the old wooden bridge completely breaks and falls apart. However, when they make their escape across the same bridge, it's intact with only a couple of wooden slats broken.
Other mistake: In flashbacks, younger Indiana Jones has exactly the same voice as the older one.
Suggested correction: Harrison Ford's voice has always sounded the same. Watch any film he's done.
It's a noticeably "older" voice than in previous films when he was about the age his de-aged self is meant to be. I mean he's now in his 80s not 40s, of course his voice is different! An unavoidable mistake but still clearly different.
Actually, it is easily possible to augment his older voice to sound young. If his older voice is too deep, for example, Ford could merely speak slightly slower when recording the dialogue - and then it could be sped up slightly in the final cut. Or, audio AI can be used to alter voice patterns as desired nowadays (ex. To remove the 'gravelly' aspect of his voice).
Harrison Ford's voice has definitely become pretty gravelly.
Factual error: When flying towards the time fissure, the German commander says that Hitler is awaiting info on the V-1 project. They're supposed to be heading for a date shortly before Germany invaded Poland. The V-1 project started in early 1942, and it wasn't named the "V-1" until June 1944.
Factual error: Basil Shaw is British, but the dates in his notes about the Antikythera are all written in American format (MM-DD-YY), as opposed to DD-MM-YY.
Factual error: Indy wakes up and has a bottle of Vicodin Es next to him, which was not introduced in the US until 1978, 9 years after the movie is set.
Factual error: The Siege of Syracuse occurred in 212 BC, during the Second Punic War, when Rome was still a republic. Some of the equipment the Romans are using in the movie, however, particularly their swords and helmets, are replicas of weapons dating to the later Imperial era.
Factual error: Shaunette Renée Wilson's (Agent Mason's) costume isn't right for 1969. That specific type of colored leather jacket, eyeglass shape, and long collared blouse in that style of geometric print didn't start being worn that way until the early 1970s.
Continuity mistake: The license plate's number of Indy's Tuk Tuk changes from 4717 to 1132 in a few shots during the Tuk Tuk Chase.
Continuity mistake: While Indy is fighting Colonel Weber on the roof of the train, Basil is pointing a pistol at them, and his grip on the pistol changes from a two-handed grip to a wrist-stabilizing grip as the shots change.
Revealing mistake: Throughout the dive boat interior scene - after they dive on the wreck - various hanging items are swinging around randomly to give the impression the boat is rocking on the water. However, none of the key light shadows - from the exterior sunlight - move at all, indicating the boat is entirely static in a studio.
Continuity mistake: When Indy arrives in Tangier at Hotel Le Atlantique, it is evening. A party is going on in the hotel while the auction is being held. A discussion starts, and a fight breaks out. They go outside, and all of a sudden, it is daytime.
Factual error: The German SS soldiers salute superior officers with "Sieg Heil!", which means, "Hail Victory." The proper salute would have been "Heil Hitler!", which was required for all branches of the German armed forces after the July 20th, 1944 bomb plot against Hitler.
Factual error: When Indy wakes up on the day of New York City's parade for the Apollo 11 astronauts, H.R. Pufnstuf is on the television. The parade was held August 13, 1969, but H.R. Pufnstuf didn't premiere until September 6, 1969.
