Corrected entry: When Esperanza shoots the pilot of his plane the sound of the engine changes its pitch immediately. Why does it do that? It is not as if the pilot's foot slid off the accelerator when he died.
Correction: When the pilot was shot, he leaned forward on the control column, which would've started the plane into a dive. When Esperanza pulls him off the controls, the sound returns to normal, consistent with the plane leveling off again.
Corrected entry: At least half a dozen planes landed at the end of the movie, yet hardly any passengers are seen moving around during the closing credits.
Correction: Since the passengers were no longer in imminent danger once on the ground, the respective crews were likely instructed to hold passengers on the aircraft until the NEA flight passengers had been cleared out, so as to not overload available resources, and given the freezing weather outside.
Corrected entry: The terrorists some how raise the elevation of the airport in relation to the ILS (instrument landing system). This causes one of the jets to crash. The ILS glide slope is broadcast from a fixed antenna beside the runway, 1000 feet from the approach end. The glide slope is fixed at (usually) 3 degrees. Even if someone changed the slope (ie, degrees of slant), it would still terminate on the runway at the touchdown zone. Besides, the pilots have charts that give all pertinent information about the ILS and also have altimeters, radar altimeters, ground proximity warning systems (GPWS), and brains (duh). All of those systems listed are on board the aircraft, independent of the ground based systems. They would not have descended into the ground even if the terrorists had tampered with the ILS.
Correction: The terrorists didn't tamper with the approach angle, but rather set the effective ground level at -200 ft. An older plane like the Windsor Air DC-8 likely didn't have a GPWS system in 1990 as they weren't required yet by the FAA, and you can hear Col. Stewart (impersonating ATC) giving them an altimeter reading that would've calibrated the altimeters incorrectly. Add to that the fact that the pilots were unable to fly visual due to the snowstorm, and you have them relying on faulty instruments and not able to realize they were too close until it was too late.
Corrected entry: Colonel Stewart and his men arrive at the airport in a helicopter. So, where do they get the Army truck they drive around in?
Correction: Colonel Stewart did not arrive in a helicopter, Major Grant did.
Corrected entry: Apparently, Colonel Stewart had anticipated quite a few casualties among his own men - he only provided for 5 snowmobiles to make their escape.
Correction: This is not a plot hole. He planned to need 5 snowmobiles. His other men may have been intended to use another route to escape or to remain behind and ensure the escape succeeds.
Corrected entry: At the end of the film when the planes begin landing there is no reason for the planes to deploy emergency chutes and send the passengers outside into the snow. All aircraft landed safely without incident. They were simply low on fuel. Planes only evacuate if there is impending danger to passengers by remaining on board.
Correction: There are plenty of reason to do so. (1) The planes were low on fuel and the landing area is a distance from the airport. So they might not have enough fuel to move back to the airport. (2) They are all now in deep snow. The planes might not be able to get out on their own power. (3) It is the middle of the night. The people on board wouldn't want to wait till they can get ladders out there.
Corrected entry: When McClane's wife is thinking about using the phone to call, there is a shot of the phone. Behind the phone, you can see a circular staircase. The aircraft she is on, an L1011 TriStar, has only one passenger deck.
Correction: The L-1011 was originally designed with a lower deck, configures either as a passenger lounge/bar or as a galley; just not all airlines bought the option.
Corrected entry: In the first shot of McClane on the snowmobile his breath can be seen in the air in front of his face. But he's driving so fast that that would be impossible.
Correction: It's not shown in front of his face, it's to right of his face, and he goes past it quite quickly. There's nothing impossible about it. I have a snowmobile myself and witness this just about every time I go out on it.
Corrected entry: When John McClain sends Officer Powell the fax of the fingerprints, notice the direction he feeds the page into the fax. The middle two fingers' prints are the first two prints to go across the scanner, followed by the outer two fingers' prints. With a fax, the first thing scanned is the first thing printed. Therefore, when Powell received the fax, the middle two prints should be at the bottom of the page with the outer two prints higher up on the page. You can see when Powell removes the page out of the machine that this is not the case.
Correction: Faxes are not "streamed" live; in other words, the data is not being printed by one machine while it's scanned by the other. Instead, the machine scans the image and creates a file. That file is transmitted to another machine, which then prints the image according to its system preferences. So it's entirely conceivable for one machine to scan from "top" to "bottom" and another to print from "bottom" to "top."
Corrected entry: After Col. Stewart has crashed the Windsor flight, he communicates with the control tower with the radio handset he used to contact the plane, every other time he uses a separate phone handset.
Correction: So he chose to use a different handset at one point. That is not a mistake, but a character decision.
Corrected entry: The interior of the plane which is deliberately crashed by the terrorists is of a BAC 1/11. I do not know any airline in the world which would choose to send a BAC 1/11 over the Atlantic from Europe due to it only being able to carry a limited number of passengers and short range capabilities.
Correction: It would be helpful to know what about the interior gives this plane away as a 1/11, as the exterior is a DC-8. Many early jets have similar or identical seating layouts and cabin appointments. I have not seen anything that obviously distinguishes this plane as a 1/11.
Corrected entry: The last scene shows the bad guys in their plane ready to take off - driving down the runway. Then Bruce gets from the helicopter to the plane's wing, fights with each bad guy, falls off, and the plane begins to take off - again. At no time did the plane turn to circle to another runway. It seems this runway was about 2 to 3 times as long as it should have been.
Correction: Have a closer look. As the 747 begins its takeoff run, it can be seen just completing a right-hand turn onto the runway.
Corrected entry: When McClain is arguing with Lorenzo in the police station, McClain shoots the gun at him with the blanks in it to make his point. Lorenzo walks over to the phone, picks it up, and says, "This is Chief Lorenzo." It has been established throughout the movie that Lorenzo holds the rank of Captain.
Correction: Rank and title are often used interchangably. In many naval services, as an example, the CO of vessel is often referred to as the captain, whether or not s/he actually holds the rank of Captain. If Lorenzo is the highest ranking officer serving in the airport, it would be appropriate to call him Chief, regardless of his rank.
Corrected entry: When McClane says 'damn it, I hate it when I'm right' during the crawl through the ventilation duct, it is clear that this line has been dubbed.
Correction: This is most likely a network TV alteration, rather than a mistake. Most US networks either edit out or re-dub scenes with expletive language to make them more family-friendly.
Corrected entry: It is not possible that a Heckler & Koch MP5 repeats with blank rounds as seen during the fight at the church. An automatic weapon, such as an MP5, repeats with gas pressure, which only is strong enough when a bullet is in the barrel.
Correction: There are different types of blanks, that do allow for the firearm to operate. The 5-in-1 style of blank, designed to cycle through firearm actions and fit a variety of firearm chambers, is also commonly used in real firearms for dramatic effect.
Corrected entry: Early in the film, McClane describes Cochrane's pistol to Lorenzo as a "Glock 7" which is made in Germany. While the model could easily be made up for the movie (there's no real Glock 7, and even the mostly non-metal models are easily detected), Glocks are Austrian, not German.
Correction: McClane is a detective in the LAPD, he is not an international arms dealer or sales rep from Glock. He doesn't know the country of origin of every type of weapon on the planet. He may not even distinguish Austria from Germany.
Corrected entry: On the plane, Holly informs the air hostess that Dick Thornberg filed a restraining order against her. She then goes on to say that this is because she knocked two of his teeth out. In the first "Die Hard" film, Holly punches Dick in the nose, not the mouth.
Correction: Because of the camera angle, we can't see the location of impact of Holly's punch. The fact that Thornburg only holds his nose doesn't preclude the possibility that the injury might've been more extensive. Also, given Thornburg's reputation and character, it wouldn't have been beyond him to have been lying about knocked out teeth when he filed the restraining order. Holly didn't stick around to see the results, so from her perspective that might've been what happened.
Corrected entry: When McClane is about to attach the church he notes that the guard is walking over his own footsteps. But there are some cars between him and the church so he can't see the guard's feet.
Correction: He is just pointing out that the guard is walking back and forth, like he is guarding something or on an outlook, not that the guard literally is walking over his own footsteps.
Corrected entry: The only reason the terrorist's plot can work is that the airports around Dulles are all closed to landings because of the violent snowstorm. If there were no storm, the pilots of the airliners in the holding pattern would simply divert to nearby airports when they started running low on fuel. If they were able to do that, the whole plot would simply fall apart. How were the terrorists able to count on the storm happening on the very day General Esperanza's flight was due to land? They didn't have any influence over the date of his flight. How did they know the storm would be so bad that all airports would be closed - except Dulles? I don't think they had any way of predicting the weather quite that accurately.
Correction: The terrorists in the film planned extensively for this operation, but the storm occurring may have just been a coincidence for them. They may also have had the plan waiting for a perfect opportunity, like a snowstorm. In the beginning of the movie, there's a news story on while the Colonel is exercising nude. The story says Esperanza's extradition has been long and drawn out, until a phone call from..." and he cuts the TV off. Given his connections, Colonel Stewart may well have been able to arrange a State Department call the week of a predicted snow storm. Esperanza's adherents may also have been able. Another scenario they may have had is to take the Air Traffic Controllers hostage (as they did) and have the other aircraft diverted for a supposed emergency, but the snowstorm worked out. Whatever the case, that element of the plot is an interesting discussion, not a mistake.