Continuity: The contents of and the ramp leading up to the truck that the terrorists arrive in.
Continuity: Spelling of Holly Gennero/Gennaro.
Continuity: Takagi's blood/brains on the glass wall.
Continuity: Al's police cruiser's lights are on as he drives up to the building. The very next shot is from John's point of view in which they are off, only to come on again when the body crashes onto the hood.
Continuity: The wound on the cop's head disappears suddenly after McClane shoots at the police car.
Revealing mistakes: The eyes of the dead terrorist in the elevator close just before Gruber touches his face.
Factual errors: It is impossible to talk and listen on a CB radio at the same time.
Continuity: The Christmas tree on the table that Karl hides behind is lying down before it gets knocked over by McClane later.
Continuity: The first and second rocket attacks both blow out the same window on the APC.
Continuity: McClane's hands while holding the wallet with the picture of his family.
Continuity: McClane swings through the window on the hose and lands on his back. In the next shot, he's on his chest.
Continuity: In the first close up where Hans is hanging from Holly's wrist, there is blood on Holly's face from John's arm. In the second close up this blood is missing.
Revealing mistakes: Obvious stunt double for McClane (missing a tattoo on the shoulder) during the fight with Karl.
Factual errors: Any interior glass such as the partition in the office has to be made of safety glass per OSHA requirements. Because of this, John's feet wouldn't be cut as portrayed.
Miscellaneous: The football game watched by the terrorist impersonating the desk guard is Notre Dame vs. USC. The date of this game varies, and it could be a bowl game, so it's possible for this game to be played on December 24. However, the game on the TV is supposed to be live, yet a day game is shown at night.
Factual errors: During the television interview, the psychologist refers to the "Helsinki syndrome." The psychological phenomenon of hostages sympathizing with their captors is the Stockholm syndrome.
Incorrectly regarded as goofs: John's vest is white when he enters the vent system and brown when he exits. It got dirty.
Continuity: When McClane is having a gun fight on the roof of the building he slides down a slide with his machine gun in the right hand; the next shot he has the gun in the left hand.
Plot holes: When the power has been cut, emergency lighting is activated in the building. If a barely finished bathroom is connected to an emergency power supply, so would presumably one of the building's most important installations be, i.e. the vault and its sealing mechanism.
Continuity: Al's panicked call for backup changes between the time he actually gives it and the time it is repeated on the police scanner. Furthermore, the gunfire and sounds of ammunition hitting his car cease to be heard on the police scanner.
Revealing mistakes: Squibs are visible on the metal door that McClane goes through when Karl shoots at him during their final fight.
Continuity: When John McClane is lowering himself down the elevator shaft with the rifle strap and the rifle comes free and he falls, you see him fall away from the shaft walls. The next shot shows him grab the vent on the next level down; something that he would not have been able to do.
Factual errors: Dulles Airport is in Virginia and is not subject to Washington, DC regulations.
Plot holes: Control towers have hand-held radios to talk to aircraft in the event of a power failure. They also had the option of using one of the planes parked on the ground to communicate with the ones in the air.
Plot holes: ILS beams (which produce altitude information) are produced from fixed antennas which have to be physically altered and meticulously re-calibrated in order to make a change in apparent altitude.
Continuity: When a black terrorist reaches down for a "present" it is a white hand grabbing the box.
Errors in geography: Pacific Bell phones and maps of Los Angeles in Dulles Airport (serving Washington D.C.)
Errors in geography: Public Utility Crew arriving at the church wearing DWP Uniforms from Los Angeles Department of Water and Power.
Continuity: A terrorist falls from a toppling metal structure, but is hit by the very top of that structure as he lays on the ground.
Plot holes: It is stated that the circling planes have "only" enough fuel for about an hour; this would give them enough time to reach as far as Georgia, Maine, Ohio, and parts of Canada.
Continuity: From the outside the plane is an L-1011, with three engines, but the cockpit has four throttles.
Plot holes: Airport runways do not have manholes. Additionally, any manhole cover which could be lifted by one person would easily be crushed by a plane.
Incorrectly regarded as goofs: The foreign military plane being used to haul cargo could well have had an ejection seat.
Factual errors: Hand grenades do not take 10-15 seconds to detonate.
Continuity: Thornberg occasionally talks into the wrong end of the skyphone in the toilet.
Crew or equipment visible: During the snowmobile chase there is a person towards the right hand side trying to flag the actors with a flashlight to go a certain way.
Incorrectly regarded as goofs: While normal practice would have been to use an internal plug to get automatic rifles firing blanks to cycle, which would make the weapon explode when shifting to live ammo, Stewart's team could have devised another mechanism.
Factual errors: While somewhere over Ohio we are told the pilot has just been given information by Dulles Tower. An en-route commercial jetliner at cruising altitude over Ohio would be communicating with Cleveland Center-- not Dulles tower or any other tower.
Continuity: Blood on Grant's face when fighting with McClane.
Factual errors: McClane destroys a plane by igniting a fuel trail that it has left on a snow-covered runway. Jet fuel is not flammable as a liquid; only its vapor is, and that won't form significantly below 100 degrees F. Hence McClane's lighter would take some time to warm the fuel enough for ignition, and the flame would travel along the fuel trail very slowly if at all.
Incorrectly regarded as goofs: At the beginning of the movie, John talks to his wife (on the plane) via a phone. She called him, and aircraft phones at the time did not accept incoming calls, so it's not surprising that they later say they can't contact her.
Continuity: Samantha Coleman is listed as Samantha Copeland in the credits.
Revealing mistakes: A construction/painting stand falls over onto a terrorist killing him, you can obviously see it is a dummy.
Factual errors: When the planes land on the fire trail we see a line of them coming in. If they were that close together, especially under the blizzard-like conditions depicted, they would all crash into each other on the runway; there simply isn't enough time between landings for all of them to taxi out of the landing path.
Factual errors: Glock does not make a #7 model as McClane claims. Glocks are also not made in Germany but in Austria. The gun shown in the scene is a Beretta 92F.
Factual errors: Glock pistols do in fact have non-metallic parts, however no porcelain is used in manufacture. Also, it would be impossible for one to pass through an airport metal detector since the barrel itself is made of steel and the pistols would be useless without bullets.
Incorrectly regarded as goofs: McClane fires on Lorenzo with blank ammo and the security guards do not shoot. First, it's not clear they were armed; second, if armed, they might not have been well trained, and finally, if armed and well trained, they might have noticed that Lorenzo and the glass behind him were unharmed.
Factual errors: The plane that Col. Stewart crashes hits the ground and explodes. Stewart asked specifically for a plane that was low on fuel yet the plane explodes as if its tanks were nearly full.
Revealing mistakes: McClane continues to fire shots at the terrorist running down the rolling catwalk even though the locked slide on his gun indicates he's out of ammo.
Incorrectly regarded as goofs: When John blows up Colonel Stewart's plane, the pilots see the flame and use it as a guide to land. The fire from the earlier crash couldn't be used the same way because they were too high at the time to see it.
Incorrectly regarded as goofs: The plot depends in part on a storm shutting down National Airport. While the terrorists couldn't depend on a storm on any particular date, they could have their plan ready to go, and simply launch it when an appropriate storm hits.
Die Hard With A Vengeance
Incorrectly regarded as goofs: Simon supplied two tickets to the baseball game, even though Zeus didn't join McClane until later. But Simon didn't know this would happen; he expected both to attend.
Continuity: A guard at the Federal Reserve Bank fires more than five times from a shotgun which only holds five shells.
Factual errors: A truck full of gold would weight about 300 tons, and would have extreme difficulty travelling up the indicated ramps. Additionally, Zeus would not have been able to wield a solid gold bar as he apparently did when smashing the car window.
Errors in geography: The Number 3 train that McClane boards at the corner of Broadway and 8th would take him further west, not in the direction indicated. Also, it does not stop on the corner of Broadway and 8th.
Crew or equipment visible: When the Mercedes rolls, it is possible to see on the upper right hand side of the screen the wire which pulls the car over.
Continuity: A terrorist says "Zwanzig" ("twenty"), which the subtitles translate to "ten."
Continuity: A terrorist in the stadium says "Wir brauchen den anderen noch." "We also need the other one" which the subtitles translate to "Well follow him."
Continuity: The level of water in jugs during the argument about racism.
Revealing mistakes: Obvious stunt taxi driver, not McClane.
Continuity: Despite being squashed between a wall and a truck, the taxi doesn't show any scratches on the side.
Continuity: The terrorists' Dodge truck that chases McClane and Zeus in the Mercedes changes at least 10 times during the scene. Headlamp covers disappear then reappear, the truck's wheel style changes, and finally, the truck gets larger off-road type tires and wheels. Also, the winch cable on the truck is unrealistically long.
Errors in geography: When McClane and Zeus inspect the toppled truck after dispatching the terrorist occupants, supposedly on the Saw Mill Parkway in Westchester County, we see an exit sign for Cos Cob. Cos Cob is part of Greenwich, Connecticut, more than 10 miles away and not sufficiently important to have a sign at that distance.
Errors in geography: The ship travels from Hudson River to the middle of the Long Island Sound in an impossibly short time.
Continuity: The position of McClane and Zeus reverses as they crawl across the cable from the bridge to the ship.
Revealing mistakes: When the taxi jumps out the park and lands on the road, the front bumper and maybe even the wheel is shown coming off. However in the next scene the car is shown in near-perfect condition.
Crew or equipment visible: In the opening scene, when the bus crosses the screen, a crew member (the director?) is clearly reflected in the bus door.
Continuity: John and Zeus are told to go to the home team dugout at Yankee Stadium, which is on the first base side, yet Zeus goes to the away team dugout, on the third base side, and finds exactly what was left for him.
Continuity: When John and Zeus slide down the wire to the boat and it chops the guard in half, the guard is pulled back by a vertical wire yet when John and Zeus drag him away he has been chopped horizontally across his waist.
Plot holes: The bombs in the movie are only dangerous when the two liquids mix. When the two liquids are still separate the bomb is completely harmless. So to defuse the bombs, the characters could simply cut one of the tubes that allow the liquids to mix and the bombs would not be able to detonate.
Continuity: When McClane and Zeus are in the taxi, as they enter the park, we see McClane turn the wheel to his left, but the next shot shows the car going in the opposite direction to his right.
Continuity: The driver's window on the Mercedes requisitioned by McClane begins with the businessman having his arm out of the window (open) and is closed when McClane and Zeus are in the car. It then changes again when the view is outside the car.
Continuity: At Yankee Stadium, the pipe in the picture behind Zeus changes size and position, depending on the view of the camera, also there is sometimes a man standing next to the pipe who disappears.
Continuity: There is supposedly only 2000 pounds of the binary liquid missing, however the bomb in the school is supposed to have 2400 pounds and the bomb on the boat is much bigger than that.