Factual error: No electricity, yet the washer is running.
Factual error: When McClane and Zeus take the little hatchback from the bank location, they run up the ramp by the Brooklyn Bridge and McClane looks to see the dump trucks aren't on the bridge. Zeus then spots them on FDR Drive and they speed off down the ramp to FDR Drive. The ramp they were on doesn't connect to the ramp they took to give chase. It only heads towards City Hall or over the bridge. They'd have to take the Civic Center ramp, do a u-turn under the Brooklyn Bridge approach then head back up the ramp to FDR Drive.
Factual error: Throughout the movie, all sorts of messages are passed over the 1MC (ship's intercom) when the boat is supposed to be stealthy. They've set "Ultra Quiet" to avoid the enemy sub but no-one was any quieter, and everyone was still using the 1MC. Worse, people are shouting commands and status updates, both in person, and over the intercom! No wonder that Akula found them. The only thing protecting this ship was plot armor! In real life, messages would be passed quietly using sound powered phones (which we also see), rather than blasting the info loudly to the entire crew, because sonar will literally pick up the sounds of loudspeakers and people shouting. Let's not even mention classified target data being passed to the entire ship's crew on the 1MC. (00:49:00)
Factual error: Angela Bennett finds the Praetorian's IP while using the PC in the Cathedral's bank: it's 23.75.345.200 - they want us to believe that this is an IP, but no IP can contain numbers greater than 255. [Common practice, like fake phone numbers, but still worth noticing].
Factual error: The suits worn by dangerous disease researchers would definitely never tear if the hose was pulled.
Factual error: When the porter first gets ready to shoot at the terrorists (after Ryback falls off the train) he goes through a series of verbal instructions to remind himself what to do. The very first thing he says is "safety off". The problem is that the gun he is using is a Glock pistol. Glocks use a device called a "safe-action trigger" but they don't have a manual safety that you turn on and off.
Factual error: A person with 60% burns on his body would not be wearing pyjamas, as the Hungarian guy does. (00:19:45)
Factual error: Near the end of the movie, as the money train is approaching the passenger train, the motorman is communicating on the microphone with dispatch. If you notice, as he is talking, his hand is NOT on the throttle. On the trains in the NYC subway system if the throttle is not depressed the train will stop.
Factual error: When it's 1969 we see a boy (I'm not sure which one so you'll have to look) riding a Shwinn Sting-Ray Krate Grey. That bike didn't come out until 1971 and they only made them that one year. (00:02:45)
Factual error: Various Sydney landmarks can be seen throughout the movie (although the Centrepoint Tower and the Monorail play major roles). There are also some cars that have right-hand steering wheels despite the story being set in California, and some Australian model traffic lights (foot-long black cover with a grey pole) can be seen when the Scorpion bot destroys a car in front of the Rangers. (01:06:00)
Factual error: The Smokers' plane is shown with every surface completely rusted reddish-brown. But planes are made from light alloys, not steel. They can eventually corrode - very slowly - but the film of corrosion is white, not red like iron rust.
Factual error: When Bond fights with Xenia in the sauna, she wraps her legs around his torso. He tries and fails to get them released, but he does create enough space between her legs which would, realistically, release the pressure on his body. (01:03:00)
Factual error: When Van Damme goes on the ice to play Brad Tolliver he punches the player with number 22, which actually was the number of Christian Ruuttu, but the player who got hit is called Dupinsky afterward.
Factual error: As Al Pacino is catching up to Robert De Niro on the freeway he uses his walkie talkie to get an update on De Niro's location. He does not take his finger off of the talk button and therefore would not be able to hear the helicopter pilot's response.
Factual error: The bullet removed from Cole's leg is totally undamaged. Even a full metal jacket bullet will be squashed when it hits a person's leg (and stops inside the leg).
Factual error: After taking off from Bangor, the pilot pulls back on the flight control bringing the plane up to level flight. However, after taking off, a plane is "nose up" and would require pushing forward on the controls to bring the nose down to level. This is also evident by looking at the attitude indicator (circle with top half blue and bottom half brown). The white line indicates the horizon and you can watch the indicator show the plane's attitude coming from below horizon (nose down) to the horizon (level flight).
Factual error: When Banderas is in the hotel room with the four dead guys, he realizes that Stallone is in the other room. When Banderas looks at the hotel TV screen, it displays the in-room guest service welcome page: "Welcome to Marriot's In-Room Guest Services". The hotel name is misspelled, while the spelling in the logo above it is correct.
Factual error: Sharp, distinct text and even graphics are shown projected from an early laptop screen onto the faces of Angelina Jolie and Jonny Lee Miller and even against a wall several feet in the background (starting 0:50:35 and throughout the rest of the movie). Of course, computer displays have never projected sharply-focused text or images onto user faces or any other nearby surfaces. (00:50:35)
Factual error: In one scene, we Dolores driving back home, after the scene where Vera tells her that accidents can 'happen' to wives husbands every day. The shot shows a huge full moon in the sky. Everyone who has every learnt any science/astronomy should know that a huge full moon cannot occur the night before a solar eclipse. (01:29:35)
Factual error: Throughout the film they show exterior shots of Alcatraz. If you pay attention you can clearly see that the Warden's house is destroyed and all that remains is a shell. Also there is only 1 guard tower. Alcatraz had many guard towers but they were destroyed in the seventies by fire. The movie takes place in the late thirties.