Cheap access to space - again (was: Audacious Tactics)

> One alternative that has been proposed (and which I rather like) is
> propane cooled to LOX temperatures. The ISP is >360 sec and you can
get
> rid of the intertank insulation, as well as having a much smaller
tank
> due to the higher density. Propane has many of the advantages of
> hydrogen without the density and deep cryogen issues.
>
> ......Andrew

I think that hydrocarbon fuels are well suited for lower stages.
They are considerably cheaper, really available and they reduce the
size of the rocket... Another great choice is kerosene which is
liquid at room temperature. If you look at the atlas/centaur it uses
Kerosene/LOX in the first stage and LH/LOX in the second stage. I
guess the theory is that you don't need to send all the carbon up
into orbit only to be burned once you get there. Besides, Kerosene,
as dose propane, will freeze solid in space or in the upper
atmosphere.

The most interesting thing is - the atlas centaur was developed in
the sixties and it was one of the best launch systems ever
developed. The idea to use Hydrogen stemmed from a belief that it
was a modern high-tech fuel. Which, for better or for worse, is true.

Jeffrey