Factual error: When the humans are capturing the gorillas, Clayton fires about 15 rounds from his double rifle. This is pretty impressive, considering this is the early 1900's.
Factual error: During the press conference, the president says that at 5:00 AM the Baldwin residence was bombed. However, the Baldwins were sunning themselves. And, if the president was referring to Eastern time, it would have been 2:00 AM in Hollywood (sign in the background). (00:26:35 - 00:27:45)
Factual error: If the access hatch to the nose wheel well on an airliner was opened at any time during the take off run every alarm panel in the cockpit would light up like a Christmas tree. The pilot would immediately abort take off.
Factual error: In the opening short "Pikachu's Rescue Adventure," in the Bellossom song and dance shot, a Poliwhirl calls itself a Poliwrath. This is obviously a mistake because of the body differences between the Pokémon.
Factual error: In the scene where the Iron Giant is spinning the boy around in a junk car he is holding, notice that the car resembles a 1959 Cadillac...however since the film is set around 1957, this is not a likely car to be found anywhere yet, much less a junk yard. (00:46:20)
Factual error: When the gang follows Ben Ravencrift home, they cross over a long bridge supposed to signify Brooklyn, but is in fact, The Golden Gate Bridge in San Francisco.