[ExI] emerging technologies may lead to a revolutionary horizontal space launcher

Adrian Tymes atymes at gmail.com
Sun Sep 19 17:25:40 UTC 2010

>up to Mach 10

Orbital speed is roughly Mach 25, so this is about right for the first stage
of a two
stage solution.  However, Mach 10 is about 7500 mph, and they say the
aircraft would
only reach about 600 mph on the rail - which doesn't have that much total
impact.  It
still needs its own engines to reach the remaining 9/10ths of its final

(Though, acceleration would be a problem if it went for Mach 10, limiting it
to cargo
launches only.  To reach 7500 mph, starting from 0, over a length of 2
miles, you'd
need to do it in roughly 2 seconds, which is around 170 Gs of acceleration.
For only
750 mph in 2 miles, you can take about 20 seconds, at only 1.7 Gs
This same acceleration could reach 7500 mph in about 200 miles - and if
building something that large anyway, a space elevator might be more

What this does do, is sneak in reusability, instead of rebuildability as
championed by
the Space Shuttle, or explicitly discardable spacecraft that are traditional
That could significantly reduce the cost of launching things into orbit,
even if the
second stage is discarded every time.

On Sat, Sep 18, 2010 at 11:32 PM, John Grigg <possiblepaths2050 at gmail.com>wrote:

> This makes me think of Tom Swift or Thunderbirds!
> http://www.physorg.com/news203515989.html
> John  : )
> _______________________________________________
> extropy-chat mailing list
> extropy-chat at lists.extropy.org
> http://lists.extropy.org/mailman/listinfo.cgi/extropy-chat
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.extropy.org/pipermail/extropy-chat/attachments/20100919/fef29a21/attachment.html>

More information about the extropy-chat mailing list