Newsgroups: sci.space.history
From: henry@spsystems.net (Henry Spencer)
Subject: Re: Apollo Technical Question
Date: Wed, 19 Jan 2000 14:13:36 GMT

In article <38857D59.9FDC913@flash.net>,
Matt J. McCullar <mccullar@flash.net> wrote:
>How exactly did the command module connect the individual wires to the
>service module?  Since the heat shield (supposedly) separated the two,
>and you couldn't have a gap in it or risk burnup during re-entry, how
>was this accomplished?  You had to tell the service module to turn on
>the big engine on the back, to fire individual thrusters, take readings
>on contents of various tanks, etc.  How were the fuel lines connected?

There wasn't actually any fuel plumbing between the two, but there was
oxygen and water plumbing, plus a lot of wiring.  All of it went through a
set of umbilical connectors on the *side* of the CM.  If you look through
photos of mated CSMs, you'll see some which show a small rectangular box
overlapping the junction between CM and SM.  That's the umbilical housing,
covering the wiring and plumbing runs, which go around the main heatshield
and come into the CM from the side.
--
The space program reminds me        |  Henry Spencer   henry@spsystems.net
of a government agency.  -Jim Baen  |      (aka henry@zoo.toronto.edu)

Newsgroups: sci.space.history
From: henry@spsystems.net (Henry Spencer)
Subject: Re: Apollo Technical Question
Date: Thu, 20 Jan 2000 05:06:17 GMT

In article <3886457a@derwent.nt.tas.gov.au>,
Justin Wigg <justinwigg@yahoo.com> wrote:
>> ...a small rectangular box
>> overlapping the junction between CM and SM.  That's the umbilical housing,
>> covering the wiring and plumbing runs, which go around the main heatshield
>> and come into the CM from the side.
>
>Did the umbilical also serve as any kind of *structural* bond between the CM
>and SM or were there other places that held the two modules together?

No, the umbilical wasn't structural.  The CM had three strengthened areas
of heatshield which rested on three pads on the SM.  CM and SM were held
together by three stainless-steel straps going through the heatshield,
which were cut (more or less at the heatshield surface) to separate them.
--
The space program reminds me        |  Henry Spencer   henry@spsystems.net
of a government agency.  -Jim Baen  |      (aka henry@zoo.toronto.edu)