[Spaceships] Designers' Championship I: ground to LEO

[thtraveller]

Originally Posted by SuperGamera

If you don't mind the extra G's in atmosphere, what about an additional high-thrust ram-rocket, only used in atmosphere? That should save you ~0.22 mps worth of fuel per trip.

I am not sure there is one? There isn't an HT option listed under Fission rockets. There is one under AM NTR rockets, but I don't think I can use that.

I am looking for a way to use water as reaction mass, because then I can go down to 1 passenger per trip and it is still more economical. As long as I can fit the drives and fuel in 17 spaces it is doable.

Hmm, 15 fuel tanks (water) plus 2 water NTR ram-rockets is tantalisingly close to doable. ... I have an idea about burning some fuel to get air speed rather than orbit, but I need to do the math.

How long does it take to get air speed from 2500 mph to 4300 mph at 3G? I think it is 30 seconds, which is almost 4 tanks of fuel.