Visible crew/equipment: When Thunderbird 1 returns to its hangar at Tracy Island at the start of the episode, the wires used to lower the rocket into the hangar can be seen.
Continuity mistake: When Thunderbird 2 is inside the hangar, it unloads Pod 1, but the numeral on the puppet-sized pod door in the close-up shots doesn't match the one on the model pod seen in long-shot.