Audio problem: As John and Gordon are fitting the new component on Thunderbird 5, John says, "It looks like we'll be another two hours before we're back in business. In the meantime, International Rescue is non-operational." But he is voiced by David Graham, not Ray Barrett.
Revealing mistake: Near the end of the episode, Thunderbird 2 lands and reverses into its hangar. During this bit, if you look carefully you can see white smoke near the boiler on the far side of the hangar, only this smoke is apparently being sucked into it. This is the usual footage of Thunderbird 2 exiting the hangar played in reverse. (00:42:05)
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.
Audio problem: When Professor Marshall says "Detonate", her lips don't move.
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.