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.
Revealing mistake: When Hauke breaks the neck of one of the American soldiers in the plane, it is very obvious that he only rests his hands on the soldier's head without twisting his neck. (01:10:14)
Revealing mistake: During the parade, after the red convertible skids, Indy's horse rears. When it turns around, check Indy's face and you'll notice that it's Harrison Ford's stunt.
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Revealing mistake: During the tuk tuk chase, skid marks from previous takes are visible on the road. (01:03:13)
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Revealing mistake: When the AA machinegun on the train goes berserk and destroys everything, Indy hides behind some crates. For several shots, Harrison Ford is replaced by a lame CGI, which transforms his head into a videogamish, lifeless face.
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Revealing mistake: When young Indy jumps from his car to the motorbike and fights against a German - and the following scene where he rides on the bike towards the train - his body and especially his face are a blatant CGI creation with unnatural movements, dead eyes, and waxy, lifeless expressions (most noticeable in theater screenings). (00:05:53)
Revealing mistake: During the flashback scene, when young Indy jumps on top of the train and runs on the roof of the carriages, it's a very obvious and lame animation with unrealistic movements.
Answer: It was never explained and seems impossible that anyone could survive such an impact. My own thought was the scene was deliberately exaggerated to appear as if Voller was killed in order to fool and then surprise the audience when he later turns up alive. I also thought it looked as if he hadn't aged. Voller may have been much younger than Indy, possibly as much as 25-30 years. When Voller reappears in the 1960s, he looks more like actor Mads Mikkelsen's actual age. The film should have made him look younger at the beginning. There's a lot of "suspension of disbelief" here.
raywest ★