"Jorge R. Frank" wrote in message
news
wrote:
On Feb 16, 10:50 am, (Rand Simberg)
wrote:
On Sat, 16 Feb 2008 09:39:48 -0600, in a place far, far away, "Joseph
S. Powell, III" made the phosphor on my monitor
glow in such a way as to indicate that:
With all the excitement experienced during the past few days with the
attachment of the Columbus module to the ISS, I was reminded of the
types of
Space Station modules proposed back in the 1980's....
These tended to have a longer design, filling up the entire payload bay
of
the Shuttle.
Does anyone know why these longer modules were rejected in favor of the
shorter ones now used on the ISS?
The older designs certainly had much more room.
Probably at least partly because longer ones would have been too heavy
for the Shuttle to get to the high-inclination ISS orbit. In the
eighties, the station was planned to be put at 28 degrees. But that's
just a guess.
Rand is right. Also $ was factor
Actually, you're both wrong. 
The modules were shortened as part of the
infamous "Fred" redesign of Space Station Freedom in 1991, two years
before the Russians were brought into the project and the station's
planned orbit moved from 28.8 to 51.6 degrees.
Astronautix is normally suspect as a source, but their Fred article was
guest-written by Marcus Lindroos and is fairly well researched:
http://www.astronautix.com/craft/spanfred.htm
"The length of the crew modules was reduced to 8.2 meters to reduce the
weight while allowing them to be tested, integrated and outfitted on the
ground rather than in space."
And when we changed from 28.8 to 51.6 degrees with the Russians, they
couldn't launch them fully outfitted anymore due to the payload limits
imposed by the inclination change. So we lost some of the benefits of doing
all of the integration and testing while the modules were on the ground. If
I recall, the US Lab was launched with a lot of empty spaces where racks
should have been.
Here's a quote from a NASA website:
When it arrived at the Station, Destiny had five racks housing
electrical and life-support systems. Subsequent shuttle missions
have delivered more racks and experiment facilities, including the
Microgravity Science Glovebox, the Human Research Facility and
five racks to hold various science experiments. Eventually, Destiny
will hold up to 13 payload racks with experiments in human life
science, materials research, Earth observations and commercial
applications.
From the "interactive" bit on the webpage, it looks like Destiny has room
for a total of 24 racks, so launching with only 5 racks installed is
launching the module mostly empty, at least in my book.
Jeff
--
A clever person solves a problem.
A wise person avoids it. -- Einstein