Newsgroups: sci.space.shuttle
From: henry@spsystems.net (Henry Spencer)
Subject: Re: Russian Space Shuttle?
Date: Wed, 12 Jul 2000 12:30:39 GMT

In article <396BDF40.286B4336@bigpond.net.au>,
David Sander  <surfren@bigpond.net.au> wrote:
>> airframe shapes that you can make that will return from orbit. Once a
>> delta-wing shape is decided open (for presumably the same military reasons
>> as the US Shuttle)...
>
>Military? Could you elaborate on that? I was led to believe the delta
>configuration was for flight stability when it was gliding at supersonic speed.

No, the original NASA designs had straight wings (relatively small ones).
Those designs had some problems and changes might have been needed anyway,
but the switch to the delta wing was specifically because of the military
requirement for a long crossrange (ability to turn during reentry, to land
at a site well away from the orbit track).

The non-negotiable crossrange requirement was never fully explained, that
I saw, but the most likely reason for it is a hypothetical "once-around"
mission:  launch to polar orbit from Vandenberg, open up, kick something
out hastily, close up, reenter and land, having made a total of one orbit.
That way you don't make highly-predictable repeated passes over hostile
territory.  Unfortunately, if you are launching this operation from
Vandenberg, there's a problem:  Earth rotates under you, and when it's
time to land, your orbit track passes about 2000km west of Vandenberg...
and there's nothing but water there.  So if you will insist on using that
launch site for a once-around mission, you need 2000km or so of
crossrange, and the straight-wing orbiter designs couldn't do that.
--
Microsoft shouldn't be broken up.       |  Henry Spencer   henry@spsystems.net
It should be shut down.  -- Phil Agre   |      (aka henry@zoo.toronto.edu)

From: jamesoberg@aol.com (JamesOberg)
Newsgroups: sci.space.shuttle
Date: 12 Jul 2000 22:25:28 GMT
Subject: Re: Russian Space Shuttle?

> The non-negotiable crossrange requirement was never fully explained, that
> I saw, but the most likely reason for it is a hypothetical "once-around"
> mission:  launch to polar orbit from Vandenberg, open up, kick something
> out hastily, close up, reenter and land, having made a total of one orbit.

Nothing hypothetical about this requirement, Henry, it was documented in a
formal MOU and called "Mission 3A/3B".