Re: LUNA: Re: indigenous fuels

Doug Jones (
Thu, 22 Jul 1999 15:20:05 -0700

Eugene Leitl wrote:
> The very best fuel on the Moon is obviously a linear motor/mass
> driver. One needs to make a ramp (using the best angle, which?)

Best angle = 0, whether launching to escape or to low lunar orbit (LLO allows much looser trajectory control due to shorter time of flight).

> Another nice point about a linear mass driver is that in the simplest
> implementation it is just a linear array of identical modules:

The trouble is, they *cannot* be identical; to get even low efficiency the inductance, capacitance, and initial voltage on the caps must vary along the length. Also, the switching speeds are the most critical design driver- solid state relays of the speed and power needed aren't cheap. I can dig up detail information if anyone is really truly interested.

Doug Jones, Freelance Rocket Plumber