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.
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.