[sci.space.shuttle] Pad - A Versus Pad - B

gandalf@pro-canaveral.cts.com (Ken Hollis) (10/06/90)

Greetings and Salutations:
 
The pads were built to be as alike as possible, so that the software in the
firing rooms would have as much commonality as possible.  Likewise the Mobile
Launcher Platforms (MLP's) are built as much alike as possible for the same
reasons.  It also helps the techs when they go to do a job not to have to
remember which pad or MLP they are on.
 
Now for the questions: 

From: ahughes@dg-rtp.dg.com (Arch Hughes)
Subject: Re: Shuttle Status for 10/02/90 (Forwarded)

|>                Columbia is scheduled to be moved to Launch Pad 39-B
Monday,
                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

>Why?  Isn't it still sitting out on 39-A (note the title of this section
>of
>the KSC report)?  Do the two pads have some
>difference or is the pad suspected of being a contributing factor in
>the leak problem?

-------> End of quote
 
Yes, you are correct.  Columbia (OV-102) is still sitting on Pad-A, MLP-3. 
And no, there is no suspect that the Pad is contributing to the leak.  The
leak is confined to the aft, there is not now any leaks in the Ground Support
Equipment (GSE).  Which brings us to:
 
From: mears@hpindda.cup.hp.com (David Mears)
Subject: Re: Shuttle Status for 10/02/90 (Forwarded)

>This reminds me of a question I've been meaning to ask.
>
>Is there any difference between the two pads?  Can any shuttle launch
>from either pad for any particular mission, or are there some differences
>which dictate which pad a given mission (or shuttle) must use?
>
>David B. Mears
>Hewlett-Packard
>Cupertino CA
>hplabs!hpda!mears
>mears@hpinddf.cup.hp.com

The next mission is OV-104, STS-41, Off Pad - A.  The mission is a DOD
mission.  From what I have been told about ANY launch, there are months and
months of verification to go through when entering the data for a launch.  If
the launch is off a certain pad, then there are a certain set of numbers
entered in, and off another pad another set of numbers entered in.  The pads
are a couple of miles or so apart (forgive me Henry Spencer if I don't get the
numbers exact...) and the Data Processing System (DPS) in conjunction with
Guidance Navigation & Control (GN&C) using the IMU's figure out where they
should go based on where they came from.  So, if you are shooting for a
particular orbit (usual orbit is 28.45 Degrees) then you would be a couple or
so miles off if you didn't have the right pad programmed in.
 
That is the reason for the shuttle shuffle.

Ken Hollis