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)
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: The side camera is visible in a couple of shots when the bus has to make the tight right turn, after the bus returns all the wheels to the ground, as it smashes into the cop car. (00:45:20)
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)
Visible crew/equipment: Aside from the mysterious other trooper(s) reflected in the tarpaulin on the roof near the start, as Keanu Reeves runs past it, you can see the clear silhouette and red light of a cameraman filming the scene. (00:11:30)
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.
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.
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)
Visible crew/equipment: When Harry's colleague hands him a printout of Howard Payne's newspaper article, a boom mic reflection is visible on the window right above the bomb schematic diagram. (01:15:15)
Visible crew/equipment: A film truck with its crew and equipment is briefly visible in the reflection of a red van four shots after Jack directs Annie onto the shoulder (use pause to get a better look). (00:46:15)
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: 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: In the scene where the bus jumps the gap in the freeway, as the bus lands, the interior camera jerks down and we clearly see the cameraman's brown shoes.
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. (00:47:04)
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. (00:50:10)
Visible crew/equipment: Close to the beginning of the film we see Jack in a coffee shop and his friend walks in. When they both leave and Jack goes to his car, a cameraman is reflected in the car window after the palm tree. (00:26:40)
Visible crew/equipment: When Sam is shot in the shoulder it shows a camera shot from the side of the bus going into a wall. In this camera shot you can see the shadow of the camera. (00:40:15)
Visible crew/equipment: After the first bus blows up, Jack talks to Howard on a payphone. The boom mic is reflected in the receiver.
Visible crew/equipment: As the end credits are starting, tracks used for a camera dolly can be seen along the left side next to the buildings. (01:50:55)
Visible crew/equipment: A camera crane is visible in the bus's rear window reflection just as it enters the empty 105 freeway via police escort. (00:53:35)
Answer: Ventilation shafts or roof panels.
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