Continuity mistake: When Thunderbird 2 leaves its hangar, it has a small "Thunderbird 2", but when we see the craft in the air, the "2" has changed to a larger font.
Continuity mistake: As Thunderbird 2 attempts to deflect the course of the KLA satellite, all the damage and charring that occurred to the satellite in the explosion earlier has disappeared, and even the attennae has been straightened.
Give or Take a Million - S2-E6
Continuity mistake: At the beginning of the episode, we see the models of Thunderbirds 1, 3 and 4 on the table next to Nicky and you can see that Thunderbird 1's nosecone near the edge of the table. But when Nicky asks for Thunderbird 3 to be launched, we see a close up of the model, and Thunderbird 1 is now situated next to Thunderbird 4.
Give or Take a Million - S2-E6
Continuity mistake: When the security chief says to Preston outside the vault, "OK Preston, check it out," you can see that Preston has nothing in his right hand, but in the next scene a baton has suddenly appeared.