When President Marshall tries to enter the conference room with the keys he got from one of the terrorists, he gets shot and there are bullet holes on the door. But somehow these bullet holes are missing in the next conference room scene when Egor comes to threaten and shoot the National Security Adviser.
Disappearing/reappearing bullet holes in the hostage room.
At 23:50, when President Marshall is rushed down to the escape pod, the editor mistakenly inserted a scene of him hiding behind a wall with a terrorist holding a gun in the background, which comes from a later scene at 35:00 (This didn't stop the film for being nominated for a Best Film Editing Oscar, though!).
In the first two thirds of the film, Major Caldwell wears a Senior Pilot badge on his uniform (wings with a star on top), both on his suit jacket and his shirt after he takes his jacket off. But in the last third of the film, he wears a Command Pilot badge (on top is a star with a wreath instead of just a star), which is awarded for a higher level of experience.
During the refueling scene when AF1 breaks away fuel is seen spraying out of the boom of the KC-10. The fuel ignites and the flame travels up the boom and blows up the KC-10. Onboard the KC-10 there is a Boom Operator who monitors and has full control of the fuel that the tanker is receiving or giving at all times and also flies the boom. The Boom Operator would have raised the boom as soon as AF1 broke away and cut off the fuel supply long before the fuel could ignite.
Major Caldwell remarks that he cannot fly a plane, yet he clearly wears Command Pilot wings on his shirt. To be able to rate the wings, Caldwell would have had to be a military pilot for at least 15 years, with at least 3000 flight hours. Even if he was not rated for multi-engine aircraft like AF1, he would have definitely been more qualified to fly the aircraft than Marshall, whose experience is limited to helicopters and small single-engine aircraft from a period dating to the Vietnam War.
C4 cannot be detonated by shooting it, as it is a relatively stable explosive. The terrorists would have had to use detonating cords or a blasting cap in order to blow open the cockpit door.
The HALO jumpers in the opening scene have parachutes made of white fabric, which is absurd for a covert nighttime operation.
When the President opens the panel to short the wires to dump fuel, the wires are all different colors. All aircraft use white wires with printed numbers and letters to identify the circuit.
None of the planes used as the real Air Force One have an escape pod. President Bill Clinton is said to have remarked on this detail half-jokingly after seeing the film at a White House screening. However, this obviously was a case of artistic license since the pod was used by the filmmakers to make a key plot twist.
They show the fax being sent and arriving at the fax machine at the White House, but it shows no one seeing it or it being passed along to members of the Cabinet. However, this was for dramatic effect, and presumably, someone read the fax off camera after the scene cut away.
When the terrorists force their way into the cockpit and try to take the plane off again, the man who takes the pilot's seat seems to have knowledge of flying a plane, but for someone desperate to take off again, he waits quite some time before advancing the throttle. In addition, the chances of a 747 taking off with drag flaps down, off a runway, with late throttle entry (given that jet engines need to spool up) are nil. The film should have ended after 28 minutes with AF1 crashing in a huge fireball.
When ordered to fire on Air Force One, the F-15 in question is seen with its afterburners on. If this were the case in reality, it would fly past Air Force One by miles.
When the President is hanging on the rope behind the MC-130, the aircraft's wing is visible through the President.
When Marshall and Korshunov are fighting, Korshunov presses Marshall's face against a panel of buttons which are obviously fake.
Only three Parachute Jumpers from C-130 landed into Airforce One. After which Liberty 2-4 had moved into receiver position. During the First Family recovery, we see that there were 4 PJs to take them along. Two for the first lady and her daughter. One for his injured Chief of Staff. We also see Fourth PJ asking for the president to move out from the plane. Where did the fourth PJ come from?
When Col. Carlton is telling Marshal how bad the damage is, his mouth under the mask is still moving after he has finished speaking.
At 1:54:32, the dialog by the rescuer is something like "There's no time for the other team," but his mouth is clearly mouthing out different script than what we hear.
In the beginning of the movie, an assault team lands on the roof of Radek's compound. They jump down a level. The white-and-blue mats they jump on become visible as they come up from the jumps.
En route from Moscow to Washington DC, Airforce One overflies Ramstein, Germany. In fact the great circle route goes over the North Pole, nowhere near Germany.
The base at which the pilots attempt to land after the hijacking is identified as "Ramstein Air Force Base." The actual name is "Ramstein Air Base"; "Air Force Base" is only used for installations in the United States.
The F-15s launched from Ramstein, Germany have "EG" tail markings, which means they are from Eglin Air Force Base, Florida. Aircraft assigned to Ramstein have tail markings "RS." Also, Ramstein does not have fighter aircraft. The nearest US fighter bases in Europe are in Spangdahlem, Germany; Aviano, Italy; or Incirlik, Turkey.
Near the end of the film during the dogfight with the Russian fighters, the sky is dark. In the next scene where Air Force One is crashing, it's dawn. The plane is supposedly heading West, and even with crossing time zones, it should be even further from sunrise.
At the speeds required to keep a 747 and a C-130 in the air, it would be virtually impossible to transfer people from the 747 safely via a cable and freewheeling pulley system. Even if the C-130 flew much lower than the 747, the force of the moving air would be more than enough to counteract gravity. Especially since in most shots the C-130 is also in front of the 747. The C-130 would have to be slightly behind the door of the 747 and nearly level with it to make an attempt even remotely feasible.
If General Radek simply got on the helicopter when released from his prison cell he would have gotten away. It was silly that his rescuers brought him a General's uniform to put on before leaving the prison, wasting precious time.
A big deal is made about the fax message sent to the White House requesting the plane be lowered to 15,000 feet to allow the hostages to escape with parachutes. Although the fax is sent successfully, and shown to have arrived, nobody picks it up or reads it. The plane is lowered anyway during refueling, yet the fax is completely ignored.
It's never explained why Gibbs betrayed the president.
The Air Force One pilot on the ground says that there is no automatic landing capability on the aircraft. All 747s have the capability to land on auto pilot. Later model 747s and every 757, 767 and 777 also has semi-auto takeoff.
Both the Russian and the American presidents speak Polish instead of Russian as do some of the Russian kidnappers.
President Marshall says in Russian: "He's dead, help," to fool one of Russian hijackers. His accent is terrible and would never fool a Russian speaker.
At one point Glenn Close's character tells Air Force one that there are 6 MIGs on its tail. All this from a moving red dot on a screen. How did she know the number?
Asking a person with no parachute experience to jump in these conditions might be more dangerous than staying on the plane. If the canopy does not rip apart (as someone already noted), they are jumping at night with only moonlight into unfamiliar terrain that might have wires, rocks, trees, water, fences, as well as the ground itself that they do not know how to land on even in bright sunshine.