Revealing mistake: In the scene before they jump the gap, they played the film in fast forward to make the bus appear to be going faster. If you watch the police on the truck in the background, they are moving in fast forward as well.
Revealing mistake: If you look at the missing part of the bridge, and look at the shadow underneath, the shadow is of a full bridge.
Continuity mistake: In the beginning, Jack shoots Harry in the left leg, yet later he limps on right leg, then left again.
Revealing mistake: After the first bus explosion when Jack answers the phone, he looks at his watch, which shows 8:05 a.m. If you look closely the watch is on alarm, not regular time.
Visible crew/equipment: When the bus is about to jump the bridge, you can see that the bridge is flat, apart from the broken part, but when the bus jumps over the bridge, there's wood and stuff piled up at the end, making it "kick".
Continuity mistake: When Jack tries to get on the bus on the highway, he hits the door window and breaks it with his elbow. Later, when he finally catches up with the bus and gets on from the moving car, the door window is intact. Several times later it is visible, no break. Then later, when the bus is on the freeway, the glass is shown broken again, but in a different pattern.
Revealing mistake: When Jack and Annie are getting off the bus via the access panel on the floor you can see wheels on the bottom of it.
Continuity mistake: In one scene where Dennis Hopper is holding the phone with one hand, he very obvious snaps with the other one just a little bit off camera. The hand holding the phone has all of the fingers, but the off-camera one is missing a thumb. How can you snap without a thumb?
Plot hole: If Jack can speed the train up, why does he not try to slow it down? Even if it can't be stopped completely, using the speed lever to reduce it to the minimum possible would be a sensible course of action. There is nothing to suggest he wouldn't be able to do this as he is able to increase the speed without any trouble. If there was something to show that slowing down the train would be unworkable it would make sense, but seems to more serve as a plot device.
Factual error: When the bus is driving over the gap in the freeway, it jumps off at an angle. And when it lands, it lands close to perfection. If the bus landed at the same angle it jumped off on, the bus would either tip over or the 2 tyres would burst.
Revealing mistake: After the first bus is blown up, if you look closely there is a truck with a chain pulling the burning bus. (Not really visible on DVD - think it was cleaned up.)
Continuity mistake: When Dennis Hopper psyches the police chief out by making him think he's on the third floor, the elevator clicks one too many times. The camera shows the numbers: "5, click, 4, click" then it switches to the police chief, during which time you hear another click. It then switches back to the numbers: "3, click." Shouldn't it be on floor 2?
Audio problem: In the scene when Jack tells the bad guy he wants to get of the bus, he says "it’s not against the rules". The bad guy then says "All right, but I want you back real fast". Look at his mouth while he says the line. You can clearly see that the talking isn't similar to the moving mouth.
Continuity mistake: When they run onto the roof near the start, there's another trooper behind Harry running onto the roof (only visible in widescreen - in 4:3 it looks like a weird reflection). In the following shot of Keanu Reeves you can see the reflections of Harry and the other guy on the plastic covering the scaffolding. We're led to believe that Harry and Jack should be the only ones up there, as everyone else has a job to do. Aside from those two shots, this third trooper disappears once they start hooking the crane up.
Visible crew/equipment: When the police officers are attempting to rescue all the passengers on the bus while at the airport by driving up beside the bus, at one point you get a front camera angle shot showing the people jumping out of the bus onto the police vehicle. If you look closely, you can see the camera man sitting on his chair reflected in the window of the open bus door, he is wearing a white shirt with sunglasses.
Visible crew/equipment: When the bus is turning right off the freeway at the start of the film, one shot shows a camera mounted on the side of the bus.
Other mistake: Towards the end when Dennis Hopper is on the subway train with Sandra Bullock, he has a gun in one hand and the detonator in the other. However, when the camera cuts to a close-up of him handcuffing Sandra to the pole, both hands are empty. If he took his hand off the detonator, the explosives attached to Sandra should've exploded, but they didn't. In the next shot, both items are back in his hand.
Factual error: When Sam opens the door for Jack to get on he pulls the handle the wrong way. On GMC buses if you pull the handle back it opens the back door which activates the rear-interlock and that makes the bus come to a complete stop.
Character mistake: At the airport, when Jack is under the bus on the trolley being towed by the truck, an accident causes all the cable on the winch reel to pay out. At this point all that's holding the cable to the reel is a small metal clamp. Jack slews around under the bus for a while, in grave danger of being run over by the vehicle's rear wheels, and then the clamp gives way (in slow motion). The now-free cable shoots toward the bus, and Jack pulls himself off the trolley just as it goes under the rear wheel. If you look at the shot where the cable is flying toward the bus, you can see two SWAT guys standing on the back of the truck, on either side of the winch. Their posture is completely relaxed and casual. Considering that for the past several seconds, Jack has been sliding around under the bus, fighting for his life, wouldn't the SWAT guys be much more excited--moving around, trying to get a better look, giving instructions to the truck's driver?
Revealing mistake: When the train is sliding along the ground near the end, there are sparks coming from the underneath (supposedly where the metal scrapes the pavement). Look more closely, and you can see that the sparks are coming from a bit of the train that's not touching the pavement anywhere.
Continuity mistake: After Keanu commandeers the civilian's car, breaks off the door and jumps to the bus the civilian loses control and heads for the water barrels in front of the divider. Right before he hits you can already see water all over his windshield.
Visible crew/equipment: In the scene where the bus is exiting the highway on that sharp curve there's a medium shot showing the bus from the driver side. Look closely at the driver, it's either a really ugly woman or that's a man in a wig driving the bus.
Factual error: When the terrorist's first target, the elevator, first has its cables blown, it goes into free-fall for about 7 floors before the brakes kick in. That is about a 100 foot free fall, and not one person even falls down afterward. Are we to believe that around 5 seconds of negative G does not even result in a single person ending up on their rear?
Continuity mistake: In the scene where Jack goes and answers the phone after the bus exploded, if you look at the reflection on the phone, it shows the explosion right behind the phone, but the bus is actually down the road maybe half block.
Factual error: The bomber demanded his money by 11 a.m., so the sun should be high in the sky toward the end of the bus situation. However, in many shots at the airport, there are long shadows, indicating either sunrise or sunset.
Continuity mistake: After the bus driver looks at the note "Bomb on Bus" he starts decreasing speed. So Keanu puts the Jaguar beside the bus and tells the bus driver to open the door for him to tell the driver to go at a speed of 50 miles per hour. Just before this you can see a camera shot in which the door is already open. This mistake is easily seen if you watch it in slow motion.
Character mistake: When Jack introduces Annie to his boss after the explosion at the airport he calls him Lieutenant McMahon but when the credits come up at the end of the film he is named as Captain McMahon.
Factual error: In the scene where Keanu Reeves attempts to stop the subway train, he accelerates the train by pushing the handle forward. In the LA Transit System, the train is stopped by pushing the handle forward.
Factual error: When the bus jumps the gap in the freeway, the front wheels rise into the air while the rear wheels are still in contact with the roadway (that has a very slight upward slope). Since its trajectory is fairly flat in the movie (unlike the ramp used to actually film the stunt), the front of the bus would fall well short of the other side. Further, the impact of landing would render the bus unable to move (which is exactly what happened to the bus used to film the stunt).
Audio problem: When Jack and Harry are running down the stairs to get to the elevator Harry radios his lieutenant and says "Mac we need more help up here now.", yet his mouth does not appear to be saying these words when it is visible.
Continuity mistake: At the start when Jack is trying to get on the runaway bus, he is seen passing the guy in the convertible Jaguar on the freeway entrance-ramp. He continues to overtake lines of stationary traffic in order to catch the bus, and then pulls alongside it. In the next shot he commandeers the Jaguar so he can use it to get onto the bus; however the Jaguar should still be waiting in the queues some way behind.
Visible crew/equipment: The first bus explodes, and the traffic on the road mysteriously disappears. If you look down the road, there are construction barriers blocking off the entire road, which would not allow any cars to drive through.
Visible crew/equipment: During the scene where the bus takes the really sharp curve it kind of goes over on two wheels - if you look closely, you can see some sort of lift under the bus obviously causing it to tilt so far sideways.
Revealing mistake: As the first bus explodes on its way from the cafe, we can see a blonde pedestrian casually walk past a window with her ears covered. At no point does she even stop to glance at the burning wreck. It seems (from her perspective) as though the explosion were merely an inconvenient loud noise and nothing worth noticing.
Revealing mistake: In the scene where Jack and Annie escape from the bus after they have gotten all the passengers off, when Annie is tying up the wheel, if you look closely, you can see that the gas gauge is at about 3/4 full. Isn't the gas tank supposed to be almost empty?
Factual error: If you look at the loop Keanu hooks the crane onto on top of the lift you can see that it and its bracket have been recently welded on (by the black residue it leaves), obviously because the lift itself didn't have such a loop. Even if such a feature existed, it wouldn't be simply spot welded on the top as this one is, it would need to be part of the lift's structure if it were to serve any purpose in supporting it in an emergency.
Revealing mistake: In the scene where Payne is waiting for the money to be dropped into the bin, he looks through the blinds out onto the street. When he lifts up the blind with his 'bad' hand, you can see his fingers and thumb taped up out of the way.
Revealing mistake: In the scene where Jack and Annie escape from beneath the bus via a trap door, the shot of them skidding across the runway shows a ring on Jack's left hand as it is wrapped around Annie. Jack is not married in the movie, but his stunt double must be.
Continuity mistake: Just after the bus driver has been unloaded and Helen tries to get off, Annie shouts "No Helen" at which point Jack turns around and grabs her shoulder to stop her. The shot switches to Dennis Hopper watching TV and then back to the bus where Jack is no longer even close to Helen when the bomb detonates.
Continuity mistake: Just before the first bus explodes, Jack leaves the cafe and puts his coffee cup onto the top of his car. When he runs back to his car, the coffee cup is different as well as in a different position.
Visible crew/equipment: When the bus is jumping the gap in the bridge, if you look closely in one shot, Sandra Bullock is not driving. Instead it's a large man that appears to be wearing women's attire.