Note: Original mistakenly sent to Michael Gardner.

----- Original Message -----
From: "John Maxson"
To: "Michael Gardner"
Sent: Friday, July 02, 2004 1:05 PM
Subject: Electrical Load Simulators


----- Original Message -----
From: "Michael Gardner"
Newsgroups: sci.space.history
Sent: Friday, July 02, 2004 12:14 PM
Subject: Electrical Load Simulators


In article ,
"John Maxson" wrote:

"John Maxson" wrote in message
...
Here's a current (modern day) application of an electrical load
simulator:

http://www.fctec.com/fctec_systemCAPdetails.asp?ID=29

Maybe some of the electrical engineering experts in the group will
be
kind
enough to compare this application with (or relate it to) the Apollo
One
situation, as described by LaDonna's Plugs-Out timeline for the
launch-pad
fire which occurred during the simulated RCS static fire test,
killing
Gus
Grissom, Roger Chaffee, and Ed White.

John Maxson

LaDonna,

I checked out the two electrical engineering forums in the 'sci'
heirarchy.
The most active one (sci.engr.electrical.compliance) has a problem
like
that
of sci.space.history. It's 98% porn! However, straightforward web
research
continues to indicate that Scott's scenario could well be close to the
mark.

I strongly suspect that (Apollo 1) load simulators were being used to
control the magnitude of the electrical load on CM and SM internal
power
sources for the Plugs-Out Test (batteries, in this case). In addition
to
Scott's scenario, I don't think it's too much of a stretch to suspect
that
NASA and/or North American didn't do a very good job of controlling
said
magnitude on the day of the fire. That could account for some of the
anomalies recorded prior to the fire (possibly a smokescreen for the
fatal
short). That's just an educated guess (without a copy of the final
test
plan and the final test configuration/procedures to be implemented
that
day).

Way too much assumption even for a "experienced space guy like
yourself".

Well, then cite a relevant assumption from my two posts. Keep in mind
that
the telemetry is classified.

The load simulators like you reference are nothing more than variablely
controlled resistance/inductance devices. Given a specified input, you
can control the offered load. If such a device had been used - and the
load, set too high - there would have been multiple indications in the
way of excessively high current flow/loss of voltage to go along with
such a setting.

It looks like you're the one making assumptions -- as to what the settings
were. Nevertheless, thanks for parroting (despite your spelling errors)
the
essence of my two posts and thus helping me make my point.

As for the RCS simulators - I don't know the details, but I can't
imagine they were anything but components designed to electrically look
exactly like RCS components, just without RCS valves attached.

Remember, the only valid references cited have been to RCS *load*
simulators, in combination with SM/CM load simulators. Additionally,
*banks
and wires* have been used to officially describe them, nothing else (to
date, at least). Finally, what you "imagine" still has no demonstrable
basis in fact, even at this late date.

Why do ANYTHING else?

You're the guy who's always claimed to have all the answers. Why not?
This
was circa 1965-66, insofar as the test design.

mgg

I hope this is of some limited help to the Grissom cause.

John Maxson
--
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