Re: "NASA Ends Project Intended to Replace Shuttle"

From: Michael Lorrey (
Date: Mon Mar 12 2001 - 09:40:30 MST

"Robert J. Bradbury" wrote:
> I think the article about the X-33 & X-34 needs to be read carefully.

Frankly I'm not too concerned. I think that there is a major conceptual
problem in the development of space travel: We are developing the most
advanced steps first. Rather than approaching it from a Conestoga to
Concorde leap, this is entirely the wrong paradigm. Air travel is only
the latest paradigm for getting from point A to point B on Earth. We
should be focusing on developing a railroad paradigm of space travel:
simple vehicles transported via large constantly usable infrastructure.
Going to an airline paradigm or automobile paradigm is much farther down
the road.

So long as we try to leapfrog like this, we will be doomed to failure
for trying too much too soon.

The mass launcher concept needs revisiting, albiet with some add-ons
that help out the math:

a) mag-lev with air vortex: You don't need a vacuum in the tube to
minimize air resistance, you need to get air speed in the tube up, like
a wind tunnel. Causing the tube to evacuate its air out the exit end via
a tornado-like vortex (the vortex prevents outside air from travelling
back down the tube), reciprocated by air-pressure (possibly boosted by
controlled/injected combustion and/or laser propulsion) behind the
projectile would assist the mag-lev launching.

b) laser propulsion 2nd stage: ground based lasers at the mountain peak
where the tube exit is would continue boosting the projectile after
leaving the tube, up to a downrange/altitude of 30-100 km and 13,000

c) scramjet/rocket chem or nuke insertion stage into orbit.

What is the mass fraction a vehicle would need if it was already
travelling 1000 mph at 15,000 on a 30 degree trajectory, from the

This archive was generated by hypermail 2b30 : Mon May 28 2001 - 09:59:40 MDT