Blooper

When Snake triggers the tracer after the fight in Madison Square Garden, Hauk follows the signal to the World Trade Center. But Snake did not take the tracer bracelet with him, he left it on the man at the Garden. It is not on his wrist for the rest of the film.

When the USPF initially go into New York immediately after Air Force One crashes, helicopter 3 is shown landing, and a large chunk of the sticky back black plastic used to create its USPF livery is peeling off and missing from the tail section, revealing the green US Army livery underneath. (The UH1 Huey used in this scene was on loan from the Missouri National Guard.) When it takes off again a few moments later, the tail is back to perfect black.

When Snake drives the station wagon through the gauntlet of convicts on Broadway, they pelt the car thoroughly with broken bricks. Immediately afterwards we see the vehicle from several angles, filthy but not actually dented.

After Snake takes off in the glider, Charles Cyphers is seen in the control room wearing a shirt and tie. In the next shot, he is wearing a suit jacket, which he then takes off. He wears the shirt and tie for the remainder of the scene.

The interiors shots of the plane before the crash are from a wide-body airliner. However, the wrecked fuselage seen on the ground is not a wide-body.

While briefing Hauk about "David 14," Rehme says the jet is "Seven miles out and closing." Even at a leisurely 300mph (the cruising speed of the Convair 580 aircraft the Air Force One model was based on), the plane would have reached them in under a minute and a half. Yet they have plenty of time to get to the control center and ID the aircraft before it even crosses the river.

When the glider is seen from the behind, its wings are drooping down. This shows that the plane in the footage is either suspended by the fuselage or stands still on the ground and is imposed on the background. A real glider in flight always has its wings arched upward towards the wing tips as the entire weight of the plane is in fact "hanging" from the wings.

When Air Force One is heading towards New York City (but before it's identified as the President's plane), it's described as a "small plane". Besides the real-world fact that Air Force One is and always has been a large passenger airplane, the footage of the plane makes it clear it's a larger aircraft than described. It would have been more accurate to describe it as a "commuter" or "passenger" aircraft even before they found out it was Air Force One.

Plissken carries an Ingram Mac-10 machine pistol with a rifle-type scope fitted on it. This is useless, since this weapon is very inaccurate. Also, the distance to the eyepiece is too large to be useful in any way.

When Snakes' glider lands on the roof of the World Trade Center, the readout states at first there is approx 90 meters (295 feet) til the drop off (end of the roof), but the Twin Towers were only 208 feet wide (63 meters)

During the sequence where Snake is being chased by the Crazies (and is about to shoot an oval pattern in a wall so he can break through), his eye patch shifts enough to reveal a perfectly good eye. This is commonly regarded as a mistake, but it is not; the novelization of the movie explains that Snake still has his left eye, but he wears the patch due to a paralyzed iris, making it extremely sensitive to light.

Gliders without engine tend to descend constantly most of the time. The glider after being released flies all the way to one of the streets of Manhattan and very close to the ground. Afterwards it starts ascending and there's no way it could have reached the top of the World Trade Center without stalling from there. Edit: The glider is later referred as a "jet glider", suggesting it has a means of propulsion, and capable of ascending. While in the lab, after Plissken is injected with the exploding capsules, Hauk explains the capsules are insurance Plissken will not fly to Canada, which would be impossible without a means of propulsion.

The American flag on the right-hand side of Air Force One's tail is not reversed. In reality it would have the stars in the upper right to represent a real flag moving forward. However, the flag could have been changed in the fictional history within the movie.

The most common rifle used by the police is the M-16 with the front handgrips removed. Apart from making firing very uncomfortable, the hands of the shooters would be in direct contact with the barrel, which becomes very hot. CLARIFICATION: Althought the original front handgrips were removed, they were replaced for the film with a thin plastic handguard around the barrel and gas tube, which would keep the shooters' hands from direct contact with the hot barrel while still giving the very slim silhouette.

When Snake gets into the station wagon after knocking out the driver, the bars in the windows can be seen to jiggle, revealing them to be rubber. This is especially noticeable in the shot from the front of the car.

The walls in the "Choc Full o' Nuts" building are clearly made of Styrofoam.

(at around 44 mins) Snake uses his machine gun to cut a hole in a door. As the camera switches to the other side and he is heard to break through the "door", it is obvious it is made of Styrofoam sheeting.

When the Duke is shooting at the handcuffed President, we hear the sound of very loud, echoing gunfire even though he is conspicuously using Snake's submachine gun equipped with a rather large silencer.

You can see a crew member giving Isaac Hayes a "stand-up" cue quite visibly in the left side of the screen when The Duke is quieting the Madison Square Garden crowd.

In an aerial shot of a helicopter flying toward central park, the camera films the right side edge of the door opening from the camera helicopter.

The characters mention (multiple times) leaving NYC via the 69th street bridge. There is no 69th street bridge out of Manhattan. It's the 59th street bridge.

The scene at the train station is clearly not in New York. The city's two rail stations, Pennsylvania Station and Grand Central Terminal both have their tracks located below ground level.

It is incomprehensible that the tape belonging to the US President would be the only copy of the nuclear fusion formula and that the government could not simply obtain another (not to mention records in print).

The Secret Service's actions with the escape pod on the doomed Air Force One plane make absolutely no sense. If the plane had been hijacked some length of time before appearing on the Liberty Island radar, they would have been able to figure out why they could not take countermeasures to stop the terrorists and regain control of the aircraft AND to get the President into the pod far away from New York City. The idiotic response actions here are mandated by the film's plotline that has the President being kidnapped inside the Manhattan prison, and don't seem remotely plausible without that excuse.

It is never explained how the criminals living in Manhattan get food since it is completely sealed off.

Bob Hauk is visibly angry when the lab technician's curt "tell him" statement forces him to reveal the arterial capsule control to Snake. The problem is that Hauk wanted Snake to know that his possible plan to escape to Canada was now nixed, and also that he either succeeded in the mission or he'd die. It's sort of possible Hauk was annoyed because he wanted to break the news to Snake himself and got usurped, but that doesn't fit the story here either.

During the bridge chase, Bob Hauk tells "Cronenberger" over the radio to get to the bridge. The character's name is listed as Cronenberg in the credits, the same as it was in the script.