It is from an actual STA. But it has been 15 years since I did the research and drew up the data, so I do not recall where it is from (and given the time plus a move last summer, I do not know where of that old research data is. I know where some is but those are binders of manuals whereas I think that STA number likely came from a drawing).

If it was an “extrapolated” dimension (such as measuring a drawing), it should have had a “Tilde” character preceding it, like this: ~ STA-xx.xx, or would have been labeled as approximate.

That STA 192.6 is also in Alway’s Rockets of the World. I did not get it from him, but that’s one confirmation source I can provide right now.

If you wanted some “real fun” correcting a kit, there is the 1/70 Estes/Semroc IB. This is 37.0” tall. Should be 37.53. But it gets more interesting, as it is visibly obvious. That very aft ring section, between STA 192.6 and STA 54, is very visibly longer/taller than it ought to be. I have figured it may have been a consequence of making the fins larger to be plenty stable with a cluster, which in turn may have caused the aft ring to be taller so the model could still stand on that ring tube and not stand on the tips of the enlarged fins. Another likely consequence is that all the first stage tank tubes are shorter, by whatever amount the aft ring is longer (and then there is also that missing .53" to be accounted for somewhere in the entire length of the 37.0" model). I do not fault Semroc for that, as they were making a faithful clone of the Estes kit.

If you really want your mind blown, consider how plastic model companies had their models done (and some may still do for new models). A large 2X (or maybe 4X) model sculpted, by eye, with photos as reference. A sort of necessarily evil for making models of planes and cars. But when they also did rockets, some of them stuck with the “by eye” method, instead of using rocket drawings to help them. Which is how some Saturn-V models got the Service Module and Apollo CM too small. I cannot recall for sure if it was Airfix, or Monogram who had that problem with their 1/144 kits, or possibly both. Also that silly error was carried over into the movie “Apollo-13”, because the people who made the computer models, used one of those inaccurate PLASTIC KITS to derive the sizes and shapes, instead of real Saturn drawings. They even compounded that mistake by using the inaccurate Saturn-V paint pattern from the model kit box art.

- George Gassaway