Michelangelo's Birthday - S3-E31
Factual error: The very beginning of the episode shows Michelangelo's Birthday circled on the calendar, and it is shown as the second Tuesday of the month as well as being the 13th day. The second Tuesday of a month can never be the 13th. The earliest the 13th of a month can be is the second Thursday.
Suggested correction: This is simply wrong. If a month starts on a Thursday, the first Tuesday will be the 6th, and the second will be the 13th.
Factual error: Early in the episode, while Jason is at the log flume, power lines and transformers are visible to the left. (00:01:15)
Factual error: When Blackthorne is on Rodrigues' ship, Rodrigues offers him grog. But grog was only invented in 1740, by British Vice Admiral Edward Vernon, whose nickname was "Old Grog" because of his preference for coats made of grogram cloth.
Reptiles in the Rose Garden - S1-E1
Factual error: After the White House is teleported to the Mushroom Kingdom, the President can be seen still using his phone, but it would not work as it would be disconnected from the landline. (00:03:44 - 00:07:19)
Factual error: In Mike's quarters, the poster of the Lunar Lander appears to have the Lander oriented incorrectly.
Factual error: When Jane is putting up the lost poster, the number to call is 1-800-saw-him. However, this is only a 6-digit phone number when it needs to be 7-digits (not including the 1-800 part).
A Ghost for Scotland Yard - S2-E8
Factual error: Bearing in mind the episode takes place in London, Sir Arthur MacCready is driving his Rolls Royce. The car has the steering wheel on the left hand side. A true British Rolls Royce would have the steering wheel on the right side. This is a Hollywood Rolls Royce.
Making Dead Things Look Nice - S4-E7
Factual error: When Carolyn leaves the hotel and gets into the taxi, you can briefly spot the license plate. In Austria, the first part has only one or two letters; here it is three letters. For Salzburg, it should be S or SL.
Factual error: The Robinsons exceeded the speed of light due to impurities in chemical rocket fuel. No chemical rocket fuel comes remotely close to the energy content needed to even approach the speed of light. That would require exotic fuels like antimatter. By Einstein's theory of Special Relativity it is impossible to exceed the speed of light with any form of rocket propulsion. Faster than light travel and time travel might be possible with the warped spacetime of Einstein's general theory of relativity and phenomena such as wormholes. For plausibility the opening scene should have been an encounter with a wormhole.
Factual error: When Nigel is in the gyrocopter thing and is over the sea/ocean, you can see off into the distance an island with what appears to be houses, but it is supposed to be prehistoric times.
Factual error: A passerby tells Sheldon Sampson that the stock market has just gone "tits up." This is a British expression that you would likely not hear in the United States, and you certainly wouldn't hear it in the 1920's.
Factual error: At the end when Skeksis enters the crystal chamber, in the overhead shot you can see 22 arcane symbols around the crystal when there should only be 18, one for each exiled skeksis. (00:45:53)
The Secret of the Unicorn: Part 1 - S1-E3
Factual error: The man selling the Unicorn tells Tintin that he can have it for 25 dollars. Tintin is Belgian and this is in his home town; they should be using francs in that time period. (00:03:30)
Factual error: The story takes place in Galveston, Texas. The geographical area is flat, but if you look closely near the last hulk out, there are mountains in the background.
Factual error: In the last minutes, the show looks forward to future challenges, in effect a preview of the never-made 3rd series. The oracle says they must find "the golden fleece, woven long ago by the Stygian witches." But the golden fleece, or indeed any fleece, is not a woven fabric. (Today's fleece is a modern invention).
Factual error: When the X-Men are surfacing after crashing their jet into the dam, Shadowcat is shown phasing through the jet and pulling Wolverine and Beast through with her. Since Wolverine's bones are coated with a heavy metal, he wouldn't be able to float to the surface. He would sink instead. (00:14:57)
What If... Captain Carter Were the First Avenger? - S1-E1
Factual error: In the intro, we are shown how Nazi Germany spreads across Europe - but after showing Denmark being conquered, it is shown to start spreading across Sweden. Sweden was never occupied by the Germans in WWII.
Suggested correction: I feel like this falls under the "Not a mistake because it's an alternate universe" umbrella. We're in an entirely different universe with a different timeline in this episode.
The show also makes a point that the only difference should be the minor choices or events befalling the MCU characters, and how these minor things have huge consequences for them, basically creating a new, alternate timeline. Basic world history before these events is not affected by the new timeline.
Suggested correction: The black spot spreading is not representing territory physically conquered by the Nazis, but more of their sphere of influence expanding. It is a steady spread and not a true representation of the war's progression. You can notice how Switzerland is also covered by the black, even though it was neutral during the war. Nor was Italy conquered, but their ally instead.
Airwolf II - S3-E2
Factual error: The computer mistakes a private airplane for a MIG-23, however the picture on the screen of a MIG-23 is completely wrong, it shows a French Dassault Super Mystere.
Factual error: Barbara shoots her revolver at the guys chasing them. When she stops and gets out of the car, she opens the cylinder and we see she only has 1 round left. However, the other chambers should still have the empty casings in them instead of being empty.
Episode #1.1 - S1-E1
Factual error: There is a view of the night sky in southern Africa. However, both the Big and Little Dippers (along with Polaris) are visible. In general, these constellations are not visible in the southern hemisphere, and where they are (North of 1° South latitude) they are very close to the horizon. The Big Dipper (Ursa Major) is to the left of the screen and Polaris (part of the Little Dipper = Ursa Minor) in near the top-center. This occurs shortly after the lion cub scene. (00:44:00)