Continuity mistake: The broken section of monorail track that is attached to the top of the centre coach when Thunderbird 2 lifts it away from the bridge is significantly longer when Virgil sets the coach down on the mountainside.
Factual error: On the night of the Hudson Building fire, the Auto Date Fixer in Commissioner Garfield's office reads 12/7/65. The next day, it reads 13/7/65, illustrating attention to detail on the part of the set decorator. Unfortunately, this overlooks the American convention for the month numeral to appear first. In the US the convention is month/day/year, in the UK the convention is day/month/year. So, either the first date should read 7/12/65 (July 12th) with the next day as 7/13/65, or the second date should read 12/8/65 (December 8th).
Continuity mistake: When Alan, Tin-Tin and Scott are lowered while on the settee to enter Thunderbird 3, looking head-on at them we have the three of them sat in that order from left to right as they descend the shaft. However, when it cuts to the long shot, Alan and Scott have magically swapped places. When they are fully raised into Thunderbird 3, Alan and Scott are back in their original positions on the settee. (00:18:50)
Plot hole: The Mighty Atom is only supposed to take pictures of human faces yet we see it taking photos of the machinery in the Saharan Plant when no one is in the room.
Plot hole: When Jeff Tracy contacts Lady Penelope, it is 10:00am in England, yet it is already daylight on Tracy Island in the South Pacific and Alan, Gordon and Tin-Tin have been out fishing for some time. (It is later established in the 1966 "spin off" movie "Thunderbirds Are Go" that there is a five hour time difference between Tracy Island and England. So, using that as a guide, when it's 10am in England, it should be 5am on Tracey Island.)
Move - And You're Dead - S1-E20
Deliberate mistake: Throughout Thunderbirds, when the script required objects to be manipulated, there were cutways to close up 'insert' shots of real human hands - usually of the puppeteers/crew. However in this episode, Alan's close-up (i.e. live action) hand is remarkably hairy with very dark hair. Yet Alan Tracey is supposed to be 21 and blond haired (including the hair on the back of his hands).
Other mistake: Just as the villains' car goes out of control in the opening sequence, a huge lump of greenery falls out of the sky in the background.
The Perils of Penelope - S1-E3
Continuity mistake: As it bears down on Penelope's perilous position, the leading car on the Anderbad Express monotrain keeps changing colour, from white and red to silver and blue.
Terror in New York City - S1-E4
Deliberate mistake: As Thunderbird 4 is shaken by the shockwave from the collapse of the Fulmer Finance building, water can be seen running down the outside of the aquarium positioned in front of the model set.
Deliberate mistake: When Selsden and Malloy try to open Penelope's safe, the bulb in Malloy's torch gets so hot that the prop torch begins to smoulder.
Move - And You're Dead - S1-E20
Continuity mistake: When Jeff Tracey is first contacted by Alan, he is sat behind his desk, but when the picture cuts back to him after a quick shot of Alan, he is suddenly perched on the front of the desk reading a magazine.
Continuity mistake: When Brains falls under The Hood's influence, he collapses, and between shots his glasses simply disappear. They are subsequently shown to have fallen off, but the action is not seen on screen: one moment the glasses are on his face and the next they have vanished.
Terror in New York City - S1-E4
Continuity mistake: Watch the time on the clock on the wall in the USN Sentinel during the missile attack. At the start of the attack it's 12.45pm, but later on it changes to 1.05pm, and when Washington informs the Sentinel Commander to stop the attack, it's now 1.35pm.
Terror in New York City - S1-E4
Character mistake: When Jeff is on the phone to Washington, thanking them for arranging the Sentinel to pick up Thunderbird 4 and take it to New York, the man in Washington replies, "That's the least we can do, Mr Tracy." So at least one person knows that Jeff is involved with International Rescue. This betrays the secrecy of the organisation that Jeff himself demands.
Continuity mistake: When we see The Hood's plane crashed into the General's mansion in a view from Thunderbird 1's cockpit window, there is a red car parked near the mansion covered in dust. But after Scott says that the stolen film could not have survived that smash, we cut back to the mansion and the dust on the red car has disappeared.
Terror in New York City - S1-E4
Character mistake: Inside the Mobile Radio Control Police Van, there is an "Ultra Short Wave" device that is labelled "Ulta Short Wave."
Character mistake: The situation in this episode is that a clerk, Lambert, is trapped inside a bank vault that is having the air removed. When IR arrives they focus all of their efforts on forcing a man-sized entrance before the air runs out, but don't consider first making a small hole to allow air in, thus giving them plenty of time to create an entrance afterwards.
Character mistake: The end of this episode concerns IR chasing down a copy of the photos the Hood taken of the Thunderbird vehicles. However, they show no concern for being photographed in person, as they're lounging around in casual clothes in the end, on an active film set with cameras everywhere, and no camera detector on their persons.
Factual error: The reactor controllers in both plants, and Brains, claim that cutting off the seawater intake would resolve the runaway reactor, and help bring it under control. In fact the opposite is the case - the plant's purpose is to purify and desalinate seawater by boiling, so processing more of it would soak up the excess heat the reaction is producing. Cutting off the intake would prevent adequate cooling, allowing the heat to build up and damage the plant further. We know the seawater isn't somehow used for fuel, because we see Scott and Virgil operating fuel rods in the reactor.
Revealing mistake: When the Plutonium store doors are blown off by the Jet-Air Blaster on the Laser Cutter Vehicle, you can see a length of string pulling the doors off from the inside.
