wrote:

Given that the shuttle SRB has 3.3 million lbs thrust and you generally
need two stages to get to orbit, would it be feasible to use a fisrt
stage consisting of the two SRB and a 2nd stage consisting of 1 SRB
with payload on top. You would need a 3rd stage I assume that is
controllable.


Do a search on "SRB-X." What you describe was designed and pushed twenty
years ago. Didn't fare so well.

--
"The only thing that galls me about someone burning the American flag is how unoriginal it is. I mean if you're going to pull the Freedom-of-speech card, don't be a hack, come up with something interesting. Fashion Old Glory into a wisecracking puppet and blister the system with a scathing ventriloquism act, or better yet, drape the flag over your head and desecrate it with a large caliber bullet hole." Dennis Miller