Newsgroups: sci.space.shuttle
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: Building boosters for Magellan
Message-ID: <1989May1.192130.9268@utzoo.uucp>
Organization: U of Toronto Zoology
References: <890418-181721-109@Xerox> <10432@cit-vax.Caltech.Edu> <4356@omepd.UUCP>
Date: Mon, 1 May 89 19:21:30 GMT

In article <4356@omepd.UUCP> snidely@inteloa.UUCP (David P. Schneider) writes:
>The point made in those discussions is that the IUS is too  light  for  any
>but  low-cost Hohmann transfer orbits.  The random thought is, why not take
>1 or more IUSs up on preceeding flights, park them,  and  then  during  the
>space  probe  flight,  and  "stack" them together to make a larger transfer
>agent.

The official NASA position is that on-orbit assembly is Really Difficult
and hence is unacceptable for mission planning.  If it was allowed, one
wouldn't mess around with IUSes; one would take the payload up on a
shuttle and mate it with something like a Centaur launched by expendable.

So we're back with the chicken-and-egg problem, again.  On-orbit assembly
will remain untried, and hence officially Not To Be Relied On, because
it's officially Not To Be Relied On and hence nobody can use it.
-- 
Mars in 1980s:  USSR, 2 tries, |     Henry Spencer at U of Toronto Zoology
2 failures; USA, 0 tries.      | uunet!attcan!utzoo!henry henry@zoo.toronto.edu