Visible crew/equipment: On the train, Jack hears Mac saying the track isn't finished, then Jack becomes aware of the broken emergency stop button. When Jack walks back over to Annie and tells her they have to jump, we can see the reflection of the standing camera operator on the right door's window, and the reflection of a crouching crew member (possibly boom operator) on the left door's window. Definitely crew given they're meant to be alone on the train. (01:45:55)
Continuity mistake: When Jack handcuffs Ray to the metal handrail, Ray's right wrist has the double strand bars facing up and single strand bar facing down, but when Jack tells the passengers about the gap and then uncuffs Ray before the jump, the handcuff's single strand bar is facing up on his right wrist.
Continuity mistake: When Jack shoots Harry, the door (to the garage) behind Payne has a deadbolt lock right above the door's finger plate, but just before the door blows up that deadbolt lock has vanished. (00:22:35)
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. (01:02:35)
Revealing mistake: The Jaguar owner holds up the piece of paper with "bomb on bus" written on it, then he loses his grip on it, and when the paper lands directly on the bus windshield, the stunt wires are visible at its sides. (00:37:35)
Visible crew/equipment: When Jack is running beside the bus and breaks the window to get the driver's attention, there's a reflection in the window of the bus of a cameraman (wearing a baseball cap) running alongside the camera. In the next scene where the bus pulls ahead, the reflection of the camera is larger and more noticeable. (00:34:35)
Visible crew/equipment: In the scene where Jack is taking off the handcuffs of the guy who shot Sam, you can see the top of a bald crew member's head with headphones on behind them.
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. (00:29:05)
Continuity mistake: When Jack runs and tries to get onto the bus on the highway, his elbow breaks the door window. In following shots this repeatedly changes. When Jack gets on the bus from the moving car later, the door window is perfectly intact. Then later the door glass is broken again, in a different pattern, while the bus is on the freeway. (00:33:40)
Revealing mistake: When the first bus is blowing up, in the shot of the right side of the bus as it's being engulfed in flames, look closely and you'll see the cable attached to the front of the bus, under its bumper, as it's slowly being pulled by the van in front of it (some DVD or Blu-ray versions may have been edited). (00:26:45)
Revealing mistake: When Payne opens the money bag in the overhead shot looking down into the bag, as the dye bomb explodes, Payne is wearing a transparent protective face shield, that is partially visible at the top left corner of the screen. Payne is not wearing a face shield in the previous or following consecutive shots. (01:42:35)
Visible crew/equipment: A camera crane on a moving vehicle is visible in the bus' rear window reflection, just as it enters the empty 105 freeway via police escort, and its long shadow then follows, at the left side of the screen. (00:53:35)
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". (01:03:35)
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. (01:39:50)
Visible crew/equipment: When the police officers on the LAX vehicle are attempting to rescue all the passengers by driving up beside the bus, there's a camera angle between the bus and LAX vehicle, as the people are jumping out of the bus onto the LAX vehicle. If you look closely, you can see camera crew reflections on the rear bus fender, and also a man sitting wearing a white shirt with sunglasses reflected in the window of the open LAX vehicle door.
Continuity mistake: At the airport the black sign on the side of the bus disappears for one shot. (01:09:00)
Visible crew/equipment: When Jack is trying to pry open the subway train's doors, a boom mic can be seen mounted on the car's interior, suspended from the ceiling. (01:40:30)
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. (01:30:00)
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. (00:11:30)
Visible crew/equipment: After Lieutenant McMahon requests to be flown to the 105 freeway interchange, a camera operator can be seen standing beside an overpass column when the bus and police escort drive by. (00:52:50)
Answer: Ventilation shafts or roof panels.
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