Best movie mistakes of 1971
Continuity mistake: When Bond escapes from the Willard Whyte facility in the desert in the moon buggy, a car that is chasing him goes over a ridge and turns on its side as the buggy speeds by. A wheel rolls back into the shot, all on its own. It doesn't belong to the car, or the three three wheelers also chasing, but looks like it belongs to the buggy, which has its full compliment of wheels all through the scene.
Continuity mistake: In the early scene when Harry walks across the street to confront the wounded robber on the street ("Did he fire six shots or only five?"), the shotgun used by the robber is lying several feet from the robber's hand, but when he reaches the robber, the camera shot shows the shotgun just a few inches from the robber's left hand.
Factual error: At the end of the movie the 1970 Challenger R/T that is shown crashing into the bulldozers is actually a 1967 Chevrolet Camaro at the time of impact. It's visible for just a few frames, from behind at impact (before exploding) and later as it stands on its nose, after the fire is put out. Note the plain steel wheels, painted silver in the latter shot.
Visible crew/equipment: Very early on in the movie, Neville is happily driving around the deserted streets. Half way through this scene the camera shows us Neville's view out the front windscreen of the car. Ahead, moving cars can be seen crossing the intersection, obviously where the streets hadn't been blocked off for the filming of the movie.
Continuity mistake: Polly Browne is in her dressing room with a picture of Tony Brockhurst on her mirror. She starts to sing and picks the picture off the mirror. As we see a close-up in her hands it is a totally different picture of Tony. As she puts it back, the photo has reverted back to the original.
Continuity mistake: When Dustin Hoffman drives into town at great speed, he swerves around a tractor going in the opposite direction. He parks the car and exactly one minute later the same tractor drives towards him from the middle of town and heads off up the same road it had already travelled. To accomplish this, it must have turned around and driven back to town at about 90 mph - about 5 times its normal top speed.
Continuity mistake: In the scene where John Wayne picks up the red box of money he lifts it onto his back and walks to an open door. As he goes out the door the camera moves to outside and we see John Wayne come out of the building. Now the red box is completely on his shoulder, rather than his back.
Continuity mistake: On Day 2, when the two officers go into the town's doctor's office, they leave the van with the driver's door way open, beyond 90 degrees, almost 180. The door didn't move to indicate it corrected itself as they went in. When they come out, the door is almost closed. And there has been no indication of a wind other than the helicopter, and that is supposed to be 1000 feet up and not even close to the office.
Factual error: When the trappers first encounter the Rickarees, the bow cannon is discharged, creating an explosion near the Indians, who promptly turn and ride away. Immediately after, a second shell explodes near them. It would be impossible for a single gunner to sponge out and reload with cartridge and ball in the space of 10 seconds.
Plot hole: While it is essential to the story, there is a problem with apes in the space ship. While it is the one that took Taylor to the future, there is no way the chimps could have salvaged the ship from the water (plus there wasn't enough time for such a salvage operation. Kira and Cornelius were living in the ape city we see in "Beneath the Planet of the Apes" never mentioning to Brent that they found a spaceship he could travel back with). They didn't have the technology for such an operation, no diving suits, and chimps are scared of water. Also, the water would have destroyed the power systems of the ship when it sank.