Corrected entry: When the operators try to shoot Indy and his father as they rotate back into the burning room, the bullets flying towards and ricocheting off the rotating wall are evidently tracer bullets. Normally, tracer bullets are not normally issued for handguns; they are used more for rifles and machine guns.
Corrected entry: When Indy makes a rubbing of the knights' shield in the tomb under the library, he dives underwater with it. This would ruin the paper and make it unreadable, yet we see him later with it and it's perfect. There's no way he had time to seal it in a water-tight container before he dived.
Corrected entry: That knight in the temple of the grail - how does he know contemporary English after spending centuries in that cave? He's only alive because of the water - he's not imbued with mystical futuristic knowledge. A Medieval English knight (assuming he even is English, since Crusaders came from all over Europe) would be speaking either Old French or Middle English, neither of which would make any sense to the modern ear; they'd both sound like foreign languages.
Corrected entry: As Donovan and Indy are looking at the tablet, Donovan's wife enters the room to say he is neglecting his guests. Donovan answers her and as she retreats from the room, she nods at Indy to acknowledge him, although in the very next shot, Indy's got his back to her. (00:19:40)ChiChi
Corrected entry: On the zeppelin, after Indy knocks the Nazi out, everyone stares at him in horror and confusion. He says to them, in plain English, "He didn't have a ticket" and EVERYONE on the zeppelin responds by getting out their tickets. The problem is, it's a German zeppelin leaving Berlin. Even if there were some people on board who knew English, it's highly unlikely that everybody on board would.
Corrected entry: When Indy is desperately trying to rescue his father during the desert tank chase, he successfully explodes one of the tank's cannon barrels, but then becomes (impossibly) entangled on the exploded barrel by his bag strap. Indy even dangles his entire weight from the strap for a couple of shots. For the Indiana Jones films, Indy's bag is and always has been a government-issue gas mask bag, made of raw canvas with decidedly weak cotton seam stitching (the gas mask bags were never expected to last more than a few years in service). For the movies, the bag's actual canvas web strap was replaced with a 60" length of seasoned and durable bridle leather (which can easily support the full weight of an adult human). The problem is not the strength of the leather strap; rather, the problem is the strength of the canvas bag stitching. The bag's strap attachments were never designed or fabricated to support full body weight, so the bag stitching should have ripped out immediately (and fatally) when Indy dangled from the cannon barrel.
Corrected entry: In the motorbike chase after the rescue of Indy's dad from the castle, you can see how they pass the border between Austria and Germany. The guardhouse is waving the Austrian flag. Austria however ceased to exist as a sovereign state after the annexation by Germany in March 1938. Looking at the weather it rather seems to be spring than winter. Therefore there would no longer be a guard at the border nor a guard house waving the Austrian flag.
Corrected entry: When Indy and Elsa are back at the hotel after the boat accident, Elsa's room is wrecked. How did Indy not know she wrecked it herself or hear her wrecking it? He was only 2 doors down. He could hear the music playing in the bathroom but not her trashing her own room. He should have known she did it when she came out the bathroom surprised. Seriously, how can you be in the bathroom and not hear someone trashing your hotel room?