Corrected entry: During the scene where agents Johnson and Johnson are flying in the helicopters, they are obviously flying in an AH-64 apache helicopter type of gunship. However when the terrorists blow up the Nakotomi roof top and one of the helicopters explodes, the helicopter used in that scene is noticably different, more like a Bell Huey type chopper.
Corrected entry: After Hans has initially introduced himself to the frightened Nakatomi employees, he proceeds to use his well-researched facts to identify Mr. Takagi in person. Surely with this much research, he could have also obtained a recent photograph of the chairman of the Nakatomi Corporation to save time.
Corrected entry: When Hans, Theo, Karl and Takagi come to Takagi's office, Hans quotes that when 'Alexander the Great saw the size of his realm, he wept, for there was nothing left to conquer.' Actually, he did weep because he couldn't conquer more - but only because his men refused to go any further (they were homesick); and reluctantly, Alexander had to turn back.
Corrected entry: When McClane confronts Hans and Eddie in the vault, he shoots Hans and Eddie in quick succession with his 9mm handgun. One problem, a 9mm round wouldn't go straight through someone even at close range, so where did the bullet hole in the window behind Hans appear from?
Corrected entry: When agent Johnson calls for the helicopters to leave in 5 minutes to attack the terrorists at the end of the film, they are standing at Nakatomi Plaza. Five minutes later they are seen in the helicopter. How did they get from the tower to the helicopters for a long ride through LA?
Corrected entry: A few of Gruber's henchmen set up the rocket-launcher to blast the armored police vehicle. As one of them swings the legs of the launcher down, another uses a 'Hilti' gun to anchor the leg in place. A 'Hilti' gun is a construction device that uses gunpowder (usually a .22 shot) to 'blast' a nail into very hard material such as concrete. The nail has to be manually loaded into the front of the gun for each shot before it can be used, however the guy using the gun never loads a nail into the gun. As it is, the result would be worthless.
Corrected entry: McClane is in the bathroom picking broken glass out of his feet, and the whole time he is having a conversation via radio with officer Powell. However, the radio is just sitting on the counter-top while the conversation continues. This is not possible since the key (talk) button needs to be depressed to transmit.
Corrected entry: John McClane opens the elevator doors and uses an axe to hold them open. Then he ties C4 explosives to a chair, uses a computer to hold it in place and pushes the makeshift bomb down the shaft. The explosion is so powerful that it takes out a good part of the torso of the building, but when the fireball gets to John the axe remains in place when it should have been blown away. (01:13:25)
Corrected entry: There is a scene, after the building is taken, where Hans gathers the hostages and asks which one of them is Tagaki. The would-be heist is obviously well-planned, well-financed, and well-scouted. He has no idea (through photos or surviellance) of what Tagaki looks like? Seems unlikely.
Corrected entry: As the terrorists enter the building, they slide a flashbang up to the guard which explodes, and then the man is shot by one of the terrorists. About a half hour later when Sgt. Powell is dispatched to check out the plaza, he walks in the first floor and right up near the same elevator area, supposedly sees nothing, then leaves. We can assume the terrorists got rid of the guard's body, but there must have been other obvious evidence of a shooting/explosion in that hallway area (blood, wall or floor damage, remnants of an explosion) which Powell would have noticed.
Corrected entry: At the beginning of the film when Holly and Ellis are talking about their Christmas Eve plans, Holly calls him Harry instead of Ellis.
Corrected entry: When McClane enters Holly's office, a crew member is reflected in the mirror. (00:12:05)
Corrected entry: When the FBI agent is telling the worker from the power company to shut of the power, the worker says that the power will be out for several city blocks. When the helicopter is taking the agents to the Nakatomi building, all of the lights are on in all of the surrounding buildings.
Corrected entry: The electromagnet locking down the vault could not have simply deactivated if the power was cut. The steel used in the construction of the vault would have developed into a permanent magnet (remanence) thus preventing the vault from being opened. Removing this remanent magnetism is very difficult, one of the simpler ways is to heat the material to its curie point, which around 1500 degrees Fahrenheit (816 degrees Celsius) in 9.0% carbon steel, the terrorists did not do this or any other method to remove the remanent magnetism.
Corrected entry: Any glass in modern office buildings is tempered glass. This kind of glass breaks into tiny, rounded pieces with semi-smooth edges. If you were careful you could easily walk on it without injury. John should not have had splinters of glass in his feet.