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. (00:13:00)
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.
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. (00:00:25)Movie Nut
Visible crew/equipment: When Bumpy hires Shaft to find his daughter, Bumpy gives Shaft an envelope with money, and when Shaft stands up you can see the bulge of the hidden microphone and wire at the front of Shaft's turtleneck sweater. When Bumpy leaves the office Shaft turns around and there's a bulge at the back of his waist, which is presumably the mic transmitter. (00:26:10)
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.
Revealing mistake: When Von Richthofen is shot down and crash-lands in the combat zone, German and British soldiers arrive and fight for possession of the Red Baron's plane. It is strange, though, that the German soldiers fire British Lee Enfield rifles instead of the German Mauser Gewehr 98.
Factual error: The movie is set at Christmas 1933.The radio that Olivia,Grandma and Grandpa Walton are listening to is a Zenith model S-232 (either 7,9 or 12-tube) which was not made until 1937.