Continuity mistake: The green Alfa in the opening minutes has its side, and mirror, wiped out by a lorry. For the next 5 minutes it then drives around in perfect condition. (00:05:43)
Factual error: The vents that Hunt and his sidekick crawl down at CIA Headquarters are standard galvanized steel box vents; they are very common in the building trade. Try walking or crawling down one - you'll make a noise like the sky is falling down. People will be able to hear you for miles. Every person in that building would know somebody was crawling about in the vent system. (This error applies to dozens of films, not only this one.)
Continuity mistake: When Portnow meets with Bishop at the church, in the first closeup of Bishop's crossword puzzle the word "MUD" is the second word across at the top, and at the center of the puzzle the 4-letter word "GEAR" is written in the 5-letter answer - with the fist space left empty. However, in the next closeup of the puzzle, now the word "ETA" is the second word at the top and "MUD" is the third, and the word "GEARS" has the "S" added, with the letter "G" started properly in the first space of the answer. (00:10:15)
Factual error: Amongst the essential parts of a nuclear weapon's detonation mechanism is a radioactive isotope of tritium, which has a half life of just 12 1/2 years. The tritium in every nuke on earth has to be replaced every ten years or so. This is by no means unusual; there are other perishable parts including detonators made of conventional explosives which would be completely inert after a thousand years. After lying dormant with no maintenance at all for that amount of time the nuclear weapons the 'Man-animals' find would be big shiny paperweights and not much else.
Revealing mistake: During some scenes, straw-stuffed Scarecrow's pant legs and his boots would sometimes have a gap that reveals the skin of Ray Bolger's leg. Two examples are, at Emerald City when Scarecrow places Lion's "cape" on him, and also when Dorothy and her friends are told the Wizard says to go away. (01:05:50 - 01:07:25)
Visible crew/equipment: After Indy and Henry have escaped from Castle Brunwald, Indy jumps into one of the boats, pulls the motor starter cord and jumps back out, then just as he bends over to release the boat from the piling, right between Indy's legs the black covered arm of a hidden crew member appears from under the tarp taking hold of the throttle, steering the boat away from the pier. (01:02:40)
Factual error: The radar guided SAMs are consistently evaded/triggered by the pilots' flares, which in reality only work against heat seeking missiles. Radar guided missiles would be defended against using chaff, basically clouds of aluminium foil strips. It was mentioned in some interviews they didn't want use chaff as it wouldn't really be visible for the audience - hence why they only deploy flares.
Visible crew/equipment: On the train, Jack hears Mac saying the track isn't finished, then Jack becomes aware of the broken emergency stop button. When Jack walks back over to Annie and tells her they have to jump, we can see the reflection of the standing camera operator on the right door's window, and the reflection of a crouching crew member (possibly boom operator) on the left door's window. Definitely crew given they're meant to be alone on the train. (01:45:55)
Factual error: When Amy is fired from S'Nuff magazine she takes her story on Aaron Connors to Vanity Fair, who run with it. That is not going to happen. Amy wrote the article while a paid employee of S'Nuff magazine and that means the copyright in the article (and, very relevant to this issue, the photographs of Aaron they paid to have taken), resides with them, not with her. It isn't hers to sell. No magazine editor of any standing is going to buy an unsolicited article without checking its provenance backwards and forwards, and that would mean checking with Amy's previous employers - after all, what would happen if they changed their minds and ran the story themselves?
Visible crew/equipment: After Willie spits in Indy's face it cuts to Short Round running through the mine, and just as Shorty turns his head toward the camera behind him, we can catch a glimpse of something blue which does not belong in this dark dreary environment, at the right side of the screen. There is a tall spotlight and two crew members, one is wearing a solid blue shirt and a cap, and the other a blue/white striped shirt with white pants. (01:21:25)
Suggested correction: This takes place in milliseconds and there's no way to see it unless you pause the image or play it in slo-mo. It should be under trivia.
Right now I have it playing on Netflix, and there is no slow motion. The striped blue shirt is noticeable as it plays without any slo-mo. If something catches my eye onscreen, it is fair game to go back and rewatch what was noticed in the first place. And in order for me to confirm what I find, I do pause, and may take screenshots. By the way, I've seen this movie countless times over the years, and it was just a matter of catching that glimpse of the color blue because it popped out against the dreary surroundings. I'll leave it up to Jon whether to move it to trivia or not.
Visible crew/equipment: When Tom and Sonic pull over and the mini drone explodes, knocking Sonic unconscious, the camera pans away and you can see emergency vehicles blocking the road on the right of the screen, presumably closing down the road for filming. (00:59:55)
Factual error: Near the end of the film, Knox is flying a Huey helicopter, and the Angels hitch a ride by shooting it with a speargun and dangling on the line behind it. Suddenly adding about 200kg to a Huey in flight like that is going to cause all sorts of problems with the trim and airspeed of the aircraft. The pilot would know immediately that something was wrong. (01:23:20)
Suggested correction: Knox wasn't a trained pilot. Either he had no clue to what was going on, or he thought something may have been wrong, but didn't know what to do about it.
Taking off and landing a helicopter are by far the most intense and difficult part of a pilot's training. Seriously, 99% of learning to fly is learning how to land and take off. If the pilot is skilled enough to take off in a Huey he is easily skilled enough to notice a massive additional drag on his helicopter due to the additional weight of the angels and the air resistance put up by such a bulky protrusion on his aircraft. If he isn't skilled enough to notice that, he isn't skilled enough to take off in the first place.
Continuity mistake: After Pongo spots Anita and Perdita walking towards the park, Pongo moves the time forward on the clock and he leaves the dial's hinged bezel open as he rushes to the door and barks, but when Roger checks the time on the clock the bezel is closed. (00:06:20)
Factual error: During the war games they have Jefferson pose as a major in order to facilitate the commandeering of the ambulance and the jeep. Regardless of their personal feelings in the matter the ambulance crew and the driver and troops in the jeep would be perfectly aware that no black man would ever be promoted to a position of authority in an otherwise all white command. We may find it repugnant today but the US Army was rigidly segregated during World War 2 - and it stayed that way until 1948. Jefferson may have been inducted into a special unit like the Dirty Dozen but considering that the future of the entire mission is riding on their success at the games, throwing it all away like that makes no sense at all.
Factual error: It is barely credible that a young Victorian woman like Elena would even think about wearing a goatskin miniskirt - exposing her legs in those days would be akin to walking about topless nowadays. Even if she did those bright yellow cotton knickers - gleefully visible in the scene in the beehive - are in no way from the 1860s. Her pants are a hundred years ahead of their time.
Audio problem: When Luke says, "Now all we gotta do is find this Yoda, if he even exists," if you look closely, his mouth never moves.
Continuity mistake: When Pierce's wife is walking in her auto shop they pan down to show her red Louboutin heels, then they cut to her walking in her office, and when they show her shoes again they have a tan sole.
Other mistake: When the stormtroopers break into the control room, the stormtrooper on the right of the screen hits his head on the door frame. On the DVD release they've added a thump when he hits it. (01:18:55)
Continuity mistake: When Sam is in his bedroom, after he finds the Cube sliver it falls and dramatically burns a hole through the floor into the kitchen. But Sam's bedroom is over the living room (there is nothing on the ground floor below Sam's elevated bathroom, and in the first movie Jazz hides in this open space), and the kitchen is actually located between the den and dining room, at the other end of the house. If they were to follow the actual floor plan of the house, the Cube sliver would have landed in the area of the piano in the living room, but where would the fun have been in that? (00:12:30)
Continuity mistake: There's an electrical outlet on the wall below the window (aligned with the window shade's loop) in Sid's room near the Megadork poster, but when Sid throws Woody to the floor and raises the shade (before he scorches Woody's forehead with the magnifying glass), that outlet has vanished.
Suggested correction: "People will be able to hear you for miles. Every person in that building would know somebody crawling about in the vent system." No, they won't. The sound from someone crawling through a vent would carry for metres but not miles. CIA Headquarters are quite large, so it's unlikely that the sound would carry to every part of it. And even if it did, there's no reason to believe that every person in the building would know that the sound was somebody crawling about in the vent system.
The galvanised steel the box vents are made out of makes a very distinctive booming sound when it distorts under pressure, and it is loud. Unless they are deaf, the people in the room through which the vent runs would know perfectly well that there was someone in there.