Bob Myers wrote:
Robert Clark wrote:
expendable or semi-salvageable while the upper stage (the orbiter ) is
reusable. As aesthetically pleasing as this configuration may appear
to some, from an engineering point of view this is precisely the
opposite of the correct way to design a partially reusable launch
system. Instead, the lower stages should be reusable and the upper
stage expendable. Why? Becasue the lower stages of a multi-staged
booster are far more massive than the upper stage: so if only one or
the other is to be reusable, you save much more money by reusing the
lower stage.

I don't say whether Zubrin's conclusion is correct or not, but the
logic in the above works only if "far more massive" always
translates to "far more expensive." I don't believe that's necessarily
the case.



There's a three-stage fully reusable Lockheed concept from the early
1960's on the bottom of this webpage, as well as a really bizarre
Aerojet-General flying wing reusable spacecraft from the same period
further up: http://dreamsofspace.nfshost.com/196...ngstations.htm

Pat