The unique connection between TV21 and A.P. Films has always led me to think that many details in those cutaways maintain a certain authenticity in relation to each series. The comic strips though, had broader aspects. (I always preferred the more mature look of the Fireball XL5 strip, in TV21) But generally, I've always enjoyed that natural affinity between my favourite comic and my favourite TV series'.
As far as I was, (and still am) concerned the so called TV21 Universe of connecting Fireball XL5, Stingray, Thunderbirds and Captain Scarlet filled in the gaps not revealed in each series, and helped to enhance my enjoyment of each series. Even though Joe 90 couldn't be part of this universe, his own comic and annuals still maintained an expanded backstory for the reader/ viewer to enjoy.
So any smarty fanboys who arrogantly state that' if it isn't in the show it ain't canon' obviously weren't around during the original days of TV21, just ask young Joe McClaine, seen here enjoying issue 183!
Anyway, here's some cutaways.
These cutaways drawn by Eric Eden ,featured some of the vehicles that appeared in Captain Scarlet, and appeared in TV21 during January, 1968.
And for Tony K , and all other Fireball fans the cutaway from the 1967 TV Century 21 annual