Factual error: The movie starts in 1985, jumps '5 years later' and then back to Sasha Luss, then '3 years earlier'. So, in her crusty apartment in an impoverished neighbourhood of 1987 Soviet Russia, Anna is filling a form on her notebook-style laptop, too modern for the era. It looks like a NEC UltraLite (considered the first notebook style laptop) which didn't even come out until 1989, let alone the likelihood of someone in the USSR having one.
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 crawling about in the vent system. (This error applies to dozens of films, not only this one).
Factual error: In circling over Washington Dulles, a plane would fly over several airports that they could land at with perfect communication, including Richmond, Baltimore, Andrews AFB, etc. Also, there is no communication from the airport to the plane but the plane would be in range of no fewer than 15 transmitting stations that could have relayed messages.
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 spear gun and dangling on the line behind it. Suddenly adding about 200kgs 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)
Factual error: Why is Hilts not wearing a uniform? A serving officer captured behind enemy lines in civilian clothing risked being shot as a spy. If a prisoner's uniform was too worn or damaged to wear, it was routine for the German authorities to replace it - a P.O.W. in civilian clothes is an obvious escape risk. He is wearing a pair of tan chinos, a cut off sloppy Joe sweatshirt, both ridiculously anachronistic - Sixties hipster fashions - and nowhere even close to a World War 2 uniform. He is also wearing Army Type III Service boots - something that would never have been issued to a fighter pilot.
Factual error: The whole basis of the trial and conviction of Cameron Poe is a crock. The judge can not arbitrarily mete out a sentence that is harsher based on the ability of someone to defend him/herself. In justifying the harsher sentence because of Poe's military skills, the judge effectively says that Poe is more guilty than an average person due to his honorable and decorated service in uniform to his country. In my entire time in law school, I never read one out of the literally hundreds of cases I was assigned in which a judge issued a harsher sentence because of someone's innate or learned abilities to defend themselves. But since this was a movie court room proceeding, the fact that Poe had a witness to the fight (his wife), the fact that he was injured in the fight, and the fact that his uniform was torn and otherwise ruined as a result of the fight are never examined. A D.A. wouldn't have taken this to a grand jury on a bet, because they would have never returned an indictment or "true bill."
Factual error: When Ray leaves his wife Gina and his car is hit by the truck he should still be in England, but when he is being chased through the streets he is in South Africa, the cops in the car are not in English police uniforms or vehicle, police livery is incorrect, and all vehicles have South Africa plates, not English number plates.
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.
Factual error: Fitch, who professes qualifications in biology, genetics and biochemistry, says that they made Sil female because she's a natural predator and so she'd be more docile. He should retake his finals. In every single species of predator on earth - every single one - the females are the hunters, aggressors and killers. The males may be socially dominant but they are the 'docile' ones. There are no exceptions - and no human DNA was used to create Sil - they used synthetic DNA based on the instructions transmitted to them.
Factual error: While Bridger is watching the film of the Mafia boss following Beckerman he signals for the film to be stopped so he can look at the close up shot of the man. He is watching a 16mm film shown through a bog standard projector - stop a film like that for more than two seconds without closing down the projector shutter (this doesn't happen - if it did the screen would darken instantly) and it will melt and catch fire. This doesn't happen.
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: Trevor - a Professor of Geology - boasts about having an article published in Scientific American, and that is not something any scientist would do. Scientific American is looked upon with slight disdain by the scientific community, considered to be a populist crowd pleaser. It is not even peer reviewed. Considering that he has just turned the geological and archaeological worlds on their heads he would have been better off publishing in Journal of Geological Research or Geology, both prestigious professional journals.
Factual error: Twice in the film it is made clear that the Pym particle works by reducing the space between atoms in order to shrink an object, and by increasing it to enlarge them. This means that the object will weigh the same, whether shrunk or enlarged - it cannot be otherwise. A 90kg man the size of an ant would punch a hole through any surface upon which he stood (and couldn't ride ants), Doctor Pym has been walking about with a 60 tonne tank in his pocket, Darren Cross lifts a full grown sheep between finger and thumb, and the supersized Thomas The Tank Engine would be far too light to crush the police car (in fact it would float harmlessly away as it would probably weigh less than the air it displaced).
Factual error: When Brendan Fraser & his son are running to reach the pyramid before the sun hits it, the sunrise line approaches the pyramid along the ground, but the sun would naturally have hit the pyramid at the top first and worked its way down to the ground. [Some people insist on trying to correct this - think of it this way. If the sun's illuminating the ground from way up in the sky, what's keeping something higher up than the ground in darkness?] (01:34:40)
Factual error: Gorillas are almost exclusively herbivores. They have been observed eating small insects and grubs but nothing larger. So why does Isabelle eat a rat at the beginning of the film? The serum may have turned her into a crazed killer, as it does with Sebastian, but it hasn't changed the structure of her teeth and palate, biochemistry of her digestive system and so on, all of which would be required. She might kill or torture the rat, but she'd never eat it.