I'm scratch-building a model of Space Shuttle Atlantis. I'm trying for reasonable scale accuracy but I'm not going to be too obsessive about it.

It turns out 1:150 is a really good scale to work at. The external tank is almost exactly a BT-70 (Scale diameter 2.220in, tube diameter 2.217in) and the SRBs are almost exactly BT-50s (Scale diameter 0.975in, tube diameter 0.976in). The Semroc BNC-50C is a close match for the SRB noses. And it will fly on an Estes C5-3 as well as D or E engines.

I've had to make my own ET nose and tail pieces, and the orbiter is going to be a pretty weird construction project no matter what scale it's at. But this is about as easy as a scale shuttle is going to get.

I'm using the pre-release new version of OpenRocket to do a rough mockup, to figure out stability, weight and balance, etc. There's a lot of dirty tricks in the file involving pods that aren't really pods, stages that aren't really stages, and such to get things positioned where I want them. I don't think any of these tricks break either the CP calculations or the boost phase of the flight simulations, so this should be usable as a simulation model. The ET and SRBs are reasonably accurate, if simplified, representations of the final design. The orbiter is not very accurate at all, the only things it's trying to get right in the model are the wing and tail shapes, approximate body cross sectional area, and the mass.

It turns out 1:150 is a really good scale to work at. The external tank is almost exactly a BT-70 (Scale diameter 2.220in, tube diameter 2.217in) and the SRBs are almost exactly BT-50s (Scale diameter 0.975in, tube diameter 0.976in). The Semroc BNC-50C is a close match for the SRB noses. And it will fly on an Estes C5-3 as well as D or E engines.

I've had to make my own ET nose and tail pieces, and the orbiter is going to be a pretty weird construction project no matter what scale it's at. But this is about as easy as a scale shuttle is going to get.

I'm using the pre-release new version of OpenRocket to do a rough mockup, to figure out stability, weight and balance, etc. There's a lot of dirty tricks in the file involving pods that aren't really pods, stages that aren't really stages, and such to get things positioned where I want them. I don't think any of these tricks break either the CP calculations or the boost phase of the flight simulations, so this should be usable as a simulation model. The ET and SRBs are reasonably accurate, if simplified, representations of the final design. The orbiter is not very accurate at all, the only things it's trying to get right in the model are the wing and tail shapes, approximate body cross sectional area, and the mass.