From: aws@iti.org (Allen W. Sherzer)
Subject: Re: Shuttle replacement
Organization: Evil Geniuses for a Better Tomorrow
Date: Sun, 22 Nov 1992 19:15:24 GMT

In article <69996@cup.portal.com> BrianT@cup.portal.com (Brian Stuart Thorn) writes:
>Allen...

>There is still *one* thing that the Space Shuttle can do that no other
>launch system is capable of... bringing things back from orbit.

At the moment there is no requirement for this capability. There simply
isn't anything we can return. The only things brought back have been LDEF
and a coupld of satellites. LDEF can be split up into several experiments
(which would allow greater access) and fly every Soyuz mission. 

Satellites cannot be brought back in a cost effective manner. The only
ones brought back had to recive hundreds of millions is subsidies from
us taxpayers.

>Whether or not it is efficient to do so is another question. I posted
>another question about why Hubble Space Telescope is not brought back
>home for repairs. There are many reasons in this case, mostly concerning
>cost and loss of productivity (however limited it would be).

Brinning Hubble back and flying it again would cost well over a billion
$$. For less, we could build a new one and launch on a Titan.

>The Shuttle, as you continually point out, is enormously expensive to
>operate and inefficient when it is operating. But I don't think putting
>a Soyuz on an Atlas (which *doesn't* have the lift capacity, BTW) or a

Atlas is close. If it can't, we can go with Titan III for far far less.

>Titan IV (which isn't much better than Shuttle) is a reasonable solution.

A Titan IV launch costs about a third of what a Shuttle flight costs.

>Shuttle certainly does not have 'twice the lift capacity' of Titan IV as
>an earlier poster contended, but it does have about one-third more, I
>believe. 

The new Titan SRMs will close most if not all of that gap.

>Someday, we might actually
>have a payload requiring all that lift, or return capacity, and as we did
>after the demise of Saturn V, we'll be saying "why did we abandon it?"

We wo't have those payloads as long as Shuttle is consuming a third of
the NASA budget. It is a millstone holding us all to the Earth.

There are plenty of heavy lift options we can go with when we need them.
All are far cheaper than Shuttle.

On a related topic (your informative background on Delta Clipper) this
>sounds like an excellent idea, but I'm nervous about it. Having grown up
>in the Cape Canaveral area, and seen my share of boosters blow up or go
>tumbling into the Atlantic, 

In the last ten years or so almost all the boosters have been blown up
by range safety.

>the idea of a powered descent and vertical
>landing gives me the willies... 

Much safer than airplanes for most people. A DC crash will only affect the
Spaceport. When aircraft crash they tend to kill people on the ground.

>I sure hope that thing has plenty of
>redundancy... rocket engines have a way of conking out at innopportune
>times.

All SSTO designs I have ever seen have at least one engine out capability.

  Allen

-- 
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
|  aws@iti.org     |  nothing undone"                                       |
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