The FBI tells McLane that Gruber was is in the East German army. However, the photo they show McLane clearly shows Gruber in a WWII German army officer's uniform. [Which would make him 75-80 years old at the time of Die Hard with a Vengeance]
While walking around in the vault of the Federal Reserve, Simon mentions that it holds ten times as much gold as Kentucky (referring to Fort Knox). The Federal Reserve actually holds an approximate total of 5,000 tons, while Fort Knox holds about 4,600. Simon also makes the claim "Fort Knox? It's for tourists!" In fact, the Federal Reserve Bank of New York offers six 60-minute tours of its gold vault each business day to the general public, while tourists are never allowed access to the bullion depository at Fort Knox.
Simon tells McClane that there are $13,000,000,000 of gold in the dump truck. This would mean, at gold prices for 1995 ($400 USD an ounce) that the dump truck is hauling 1015.5 tons. According to dieselpowermag.com 10 Largest Dump Trucks page (these are the massive open pit mining dump trucks) they carry anywhere from 400 to 280 tons. The Federal Reserve Bank holds about 5000 tons, equally divided by 14 dump trucks would mean each truck is hauling just over 347 tons (still more than the dump trucks in the movie could haul) and worth only $4,500,000,000.
SImon alleges that "one ounce more or less" than four gallons will result in detonation. This is greater than 0.2% precision, which rivals that of well-manufactured volumetric glassware and is unlikely to be achievable with cheap plastic jugs. Furthermore, there does not appear to be a fill line on either jug, making a precise measurement impossible.
When John and Zeus are in Tompkins Square Park they see that they are being sent to Yankee Stadium, and thus John says, "Where is the nearest A train?" The three subway lines that go to Yankee Stadium are the B, D, and 4. At Tompkins Square Park the closest subway line to them happens to be the 4 train, regardless of their destination, thus it would not even make sense for them to walk across town to the A train and transfer lines at a later point.
In the van, Bill Jarvis mispronounces "Mathias" with the English "th" consonant cluster (as in the word "with"). In German, the "t" and "h" are pronounced separately, so the name should be pronounced like the English words "Mat high us" but all run together.
When Zeus was driving the cab and the guy asked him to go to 112 Wallstreet or he'll have his medallion suspended. Even if Zeus was a real cab driver, a civilian has no authority whatsoever to suspend cab driver's medallion or even make that kind of threat.
McClane uses a mixture of the binary liquids to blow the handcuffs off Zeus on the container ship. The amount he uses would have been enough to blow at least one of Zeus' hands off (in comparison to the amounts used as a demonstration earlier on in the film).
While John and Zeus race toward the subway in a commandeered taxi, John is forced to drive between two vehicles that are too close together to fit the taxi. Upon slamming through, both side mirrors are ripped off and scuff lines are made on the side of the car. In every shot afterward, the mirrors are still intact. However, the scuff lines remain.
When Zeus drops McClane off to intercept the bomb on the subway, McClane stands in the stairway and a blonde woman passes behind him twice in the same direction. There is also a brunette in a red blouse who passes McClane twice - in front of the blonde woman the first time, then behind her the second time. At least one other extra, an older man with gray hair in a gray suit, appears twice as well.
When John is looking for the bomb on the subway he under the seat of a blonde woman wearing a light tan dress, later when John throws the bomb from the train, THE TRAIN HASNT STOPPED YET and the same blonde woman wearing the same light tan dress is already standing on the subway platform running away from the explosion.
When McClane finds the bomb on the train, he starts moving in the same direction the train is travelling, meaning he would be moving towards the front. However, when he throws the bomb from the train, he is at the back.
McClane says that the Yankees tickets were behind the home team dugout at Yankee Stadium, but when Zeus arrives at the stadium, the seats he goes to are behind the visitors' dugout. The Yankees' dugout says "New York Yankees" on top rather than "Welcome to Yankee Stadium", which is seen in the film. Also, the right field foul pole, down the first base line, can clearly be seen behind Zeus.
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.
The amount of time that passes after John and Zeus catch the ship passing under the bridge with the winch from the jeep and the time they shimmy down the cable would have killed them from the fall; there is no way they could survive the 200-foot fall, land on their backs as shown and walk away, let alone survived.
When the janitor at Chester A. Arthur Elementary is making his final rounds and checking all the classrooms for any children, he looks in the room where the children ultimately are and, looking at the teacher's desk, sees the sunlight coming through the window reflected on the tile floor. He locks the room and moves on. When they cut back to show the desk again from the exact same angle, the sunlight reflecting off the tile is now blocked by the children (actors) now hiding under the desk, the tile in front of the desk now in shadow, revealing that the children were not under the desk in the first shot.
As the ship passes under the bridge, we can see how fast it's moving. When the winch cable goes taut and drags the truck, it should pull the truck at the same speed as the ship. But the truck moves MUCH slower.
In the beginning of the subway scene, a LED sign that denotes the day and the time says that it is Tuesday. However later in the movie at the school, the principle states to the children that it is Friday.
At Yankee Stadium, the pipe in the picture behind Zeus changes size and position, depending on the view of the camera. Also in some shots there is a man standing next to the pipe; in other shots he is not there.
The wrist watch John is wearing throughout the movie changes model several times. The 1st half of the film he is seen wearing a Breitling Chronomat , but after he is thrown from the water pipe and sorts through the coins in the dead drivers pockets of the car they force off the road , the face of the Breitling is missing the chronograph and the watch has a serrated bezel not like the Chronomat.
it then switches back before they attempt to board the boat , and then reverts again when handcuffed. This is seen clearly in the Blu-ray version.
The amount of time that passes when the ship goes under the bridge that John and Zeus are standing on. The ship would have been long gone by the time they had gotten the cable out from the jeep's winch and actually had it catch onto the top part of the ship.
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.
When the robbers are driving into the aqueduct, the last truck knocks the steel bridge down (making escape from the same road impossible), with the part facing the ENTRANCE falling into the ditch. The metal plate can easily be reinstalled from the inside of the tunnel. Yet when McClane goes back through the tunnel, he finds that the metal plate has fallen with the downside ledge on OTHER side of the ditch, making it unreachable. The plate has reversed itself.
As McClane and Carver stop on the bridge and observe Gruber's boat, a cutaway reveals the ship to be Panamanian-registered, yet when Zeus drops the end of the cable onto the ship, an American flag can briefly be seen atop the superstructure.
When Zeus arrives at Yankee Stadium and reads the words "Game Over" from the pocket baseball game underside, behind him is big water hose being moved around, but in the next immediate cut the hose has completely disappeared.
In the cab, when John and Zeus are introducing themselves, out the back window you can see an SUV going in and out of the picture. There's a crew member with a camera pointed out of the passenger window.
At one point the dump trucks are supposed to be traveling on FDR Drive. The FDR is for cars only and does not allow trucks. The dump trucks would not only have been pulled over, but they would have been too tall to clear many underpasses and tunnel entrances as well.
The dump trucks are supposedly heading north on the FDR drive; however, Simon's truck approaches a sign that says "Cadman Plaza West". This is a sign on the Brooklyn Queens Expressway in Brooklyn, across the river from the FDR drive.
Simon and Katya are making their escape from the cargo ship supposedly in Long Island Sound. The boat they lower off the side has a hull identification number starting with CF. These letters stand for "California Fleet" and are only used on boats in California.
On standard truck winches, like the WARN winch used on the Dodge truck, the manufacturer recommends that at least five complete wraps of wire remain on the drum as the minimum to make a safe winch pull. So if the winch cable "ran out" as it did in the scene, as the truck started to get pulled, the only thing holding the winch cable onto the winch drum is a small bolt. If the weight of the vehicle is applied to that small bolt (versus the other end at a static object), the winch cable would snapped off.
When McClane and Zeus are in the Mercedes, McClane asks Zeus to disconnect the ABS brakes so he can spin the car, and tells him to pull out fuses from the fusebox. The fusebox on a late '80s S-class Mercedes is not where Zeus finds it (it's under the hood) and if you pull fuses at random, the car could be rendered undriveable (fuel pump fuse, for example).
As the winch cable pays out, we hear a ratcheting sound which is not made by a freespooling planetary winch. And the only way for the cable to stay tight with 2 men on it would be if it was locked, or spooling under a load. If it was freespooling as the plot indicates, it would immediately spool out slack as soon as the first man's weight went onto it.
The dump truck in the aqueduct could not possibly have gone from reverse to forward as shown (a "bootlegger" turn) when John was trying to outrun the water that gushed after Simon blew the dam, as the truck would be far too heavy and in too small a space to perform the maneuver.
When Zeus enters Yankee Stadium, the Stadium was empty and the grounds crew was out taking care of the field. In reality, Zeus would not be allowed inside the stadium. You are only allowed inside baseball stadiums several hours prior to a game.
Each of the fully-loaded dump trucks full of the stolen gold weighed over 350 tons (750,000) pounds. There is no way they would have been allowed onto the FDR bridge, or any other bridge in the U. S., with the maximum lawful load being nearly 1/10th of that which was shown, or 80,000 lbs. The terrorists, as educated as they appear to be, should have known this, as they would have been stopped and arrested as soon as they got to the first bridge.
Impossible physics with the stolen Mercedes spinning in place as it continues going forward but is pointing backward. In reality, whipping the front end of the car around in either direction would cause the car to go in that direction and would not spin in place, and furthermore, shifting in reverse at exactly the right moment would be impossible, even with the anti-lock brakes disabled.
Although in other scenes Inspector Cobb wears the correct NYPD badge for his rank, when McClane and Zeus are rescued after the ship explodes near the film's conclusion, he is wearing a lower ranking Lieutenant's badge.
The Quebec police officers responding at the end of the movie are depicted as wearing tan outfits with state trooper-style hats. No federal, provincial or municipal law enforcement agency in Quebec has any remotely similar duty uniform.
Around 32 minutes into the movie McClane pulls up a sidewalk grate to jump onto a subway car. Sidewalk grates do not provide direct access to the subway, and cover the platform not the rail right of way.
When they find the bomb in the school the timer on the detonator reads 32 minutes before the bomb goes off. The officer spends all that time trying to diffuse the bomb, but all they had to do was drain one of the liquids out of its container so that the two binary liquids could not be mixed together to become a bomb.
John and the truck driver are driving through the aqueduct when the truck driver says there is 500 feet of rock above them. Passing under one of the vents to the surface, we can clearly see there is less than 100 feet of rock above the aqueduct.
Larry Bryggman's character, Walter Cobb, is listed as "Arthur Cobb" in the credits. This is because his full name is Arthur Walter Cobb. More than once thru the film he is called both Walter and Arthur.
When John McClane is going over the rock and lands at Central Park the rear tire can be seen coming off, but in the next scene the taxi still has all four tires. However, watching it frame by frame you see the taxi cab come down and it doesn't have chrome hubcaps, the loose wheel does, and just before the shot changes, you see the taxi's wheel still intact, never having fallen off. The rogue wheel is from the taxicab they land on.
A drive from New York City to the Quebec border takes about 5 and a half hours - probably slightly more if driving a truck. Even if Simon's henchmen did have a head start, they would still be somewhere in New York state by the time McClane figures out their destination. That would have given American authorities plenty of time to intercept the trucks along the way inside their own borders. Moreover, even if the trucks would have had the time to make it to the Canadian border, they would have been caught by customs with a very suspicious cargo of bulk gold bars.
Ricky Walsh is present during the meeting in the van with the FBI, sitting in the front passenger seat and would have a clear unobstructed view of the pictures of Peter Gruber and Mathias Targo in the FBI folder. So he could have easily identified Peter Gruber when he introduced himself as Bob Thompson from the City Engineer's Office. He also takes a good glance at Mathias Targo when he jumps on one of the trucks so he could have easily identified him as well.
The German spoken in the movie is pretty poor. Most of it is spoken by actors trying to speak German. Only the actor giving orders in the Stadium seems to speak German. He speaks with a Bavarian Accent. He is the only one in the entire movie who's German is somewhat correct. Besides the accent, the grammar is often incorrect. It seems that they just took the English words and replaced them with German ones, without any regard for the real German grammar, which is often quite different. Further more, they often have people speaking English with a fake German accent. No Native German Speaker would sound like that, when speaking English.
At the Elephant Water Fountain scene, a white truck driving in the background has a passenger (in a blue shirt) leaning out of the window and keenly observing the goings-on of actors Bruce and Samuel (as well as the entire film crew).
When the mercenaries are gathered in the warehouse near the end with the trucks filled with gold bars, one of them opens a truck and bars spill out onto the ground. One of the bars is clearly an unpainted lead bar.
When McClain is in the aqueduct tunnel and shoots the men in the truck, you can hear him make 7 shots, yet there are 12 bullets holes in the door. Also, when the door is opened you can see only 2 of the 12 bullets penetrated the inner panel even though each bad guy was hit by 3 bullets each.
When Katya shoots the comrade who discovered the gold had been replaced with scrap iron, the hammer moves to the cocked position as she pulls the trigger, the hammer stays in the cocked position as she fires three times.
Early in the movie when Cobb is giving out assignments, one of the assignments was about the theft of dump trucks. The movie takes place in NY City and yet when we see the dump trucks show up to Wall St. during the heist, all of the trucks have New Jersey license plates.
When McClain is in elevator of the bank and shoots the last man, the blood splatters all over the right side of his face including his ear. In the next scene when McClain aims his gun at Zeus, the blood is no long on his ear and only on the front area of the right side of his face.
When McClain jumps the Mercedes off the FDR and goes they the wall, while the car is in midair the front end is intact. In the next scene the front end is all smashed up. If it had really smashed thru the wall the front end would have been damaged on impact with the wall.
The goof items below may give away important plot points.
When McLean and Zeus solve the water riddle they realise that they need to pour water out of the full 5-gallon bottle into the 3-gallon bottle which currently contains 2 gallons, leaving 4 gallons behind. However the 5-gallon bottle needs to be full first, and it clearly isn't.
When John and Zeus get the first riddle at the pay phone, they have 30 seconds to solve it and call the terrorist before a bomb goes off. They don't solve the riddle in 30 seconds, but in 40 (according to the answering terrorist). The actual time for the riddle was 64 seconds.
Zeus states that there are 2,401 characters in the St. Ives riddle. This is actually only the quantity of kittens. There are also 343 cats, 49 sacks,seven wives, the husband, and the narrator, totaling 2802 characters.
At the Quebec truck stop, the helicopter McClane and Zeus are in is forced to land after getting shot by Simon. When McClane can't get Zeus out of the helicopter, he decides to draw Simon's fire. The next scene shows the copter's blades completely still, even though helicopter blades take a little while to slow down and stop.
When the Federal Reserve Bank guard decides to make an ultimately futile stand with the pump-action shotgun, he rattled off between 12 and 14 rounds without a reload. Commercially available pump shotguns hold 5 shells, military versions hold no more than nine.
After everyone finds out there is no gold on the boat on which MacLane and Zeus are held hostage, after the bomb blows up, there is not a hint of shrapnel, the volume of which would have caused it to rain down for at least 30 seconds after the explosion.
The bomb was delivered at the Chester A. Arthur School in the morning of the same day. Although it was impossible to know that Zeus Carver's kids were at that school, since he was accidentally involved, Simon at no point indicated that it was targeted at his kids, and could have been a coincidence. The sole purpose was to get the cops out of downtown, not to target Zeus.
John McClane could have easily gotten killed during his first task (carrying the sandwich board with the racist remark through Harlem), but Simon needed McClane to stay alive until the explosion in the subway to gain access to the gold. If McClane would have died in Harlem, Simon could have told the police about the subway bomb anyway, but he couldn't have used his cover-up story (revenge for his dead brother) any longer without raising suspicion among the police. It contradicts his otherwise fool-proof plan.
Not one character who knows or comes to know of the Federal Reserve heist either remembers, cares, or thinks it important enough to mention that $13 billion of the stolen gold is laying in the Aquaduct following the dam explosion. All anyone seems concerned with is dredging the non-existent bullion from the bottom of Long Island Sound.
There is no need for the thieves to seize control of the front office of the bank, upstairs at ground level. They could have all entered the vault from below, emptied it, and left without the bank employees knowing. The only reason for them to be upstairs was to allow the scenes with Katya's dagger, and the elevator fight.
Officer McClane finds the subway bomb in the first car (front) of the train, then proceeds to walk to the last car (back) of the train prior to detonation. We see the signal sent to detonate the bomb when the first wheels roll over the trigger. Simon's plan appears to be fairly precise, so it's reasonable that he would have planned the bomb to be in the first car when it exploded (i.e. at that location on the track). Since McClane had moved the bomb at least several hundred feet, the bomb is no longer in the planned location and could have spoiled the plan.