Burns,
I'll have to listen again.. and yes they reset it before TLI. They were quite busy during the parking orbit. Dick Gordon had to realign and reset the guidance platform, no easy task considering he had no reference as he normally would have. Also he had trouble identifying the Alignment Stars as there was a lot of debris from the jettison of the Optics cover and the alignment stars were in the southern part of the sky, and were not the brightest stars n the catalogue. While he was at that Conrad and bean had to bring the fuel cells back on line and get all the electrics & systems up & running. Conrad was concerned that the forward RCS thrusters may have gotten water in from the rain and possibly frozen (Which fortunately was not the case. All this and the usual pre TLI tasks.
As for Apollo 11, most folks think the words spoken on the moon were "Houston Tranquility base here, the Eagle has Landed" Not so. They were Aldrin: "ACA out of detent" Armstrong: "Out of detent Auto", Aldrin: Mode Control, Both Auto, Descent engine command override, off. Engine Arm off, 413 is in".
The ACA was the Attitude Control Assembly which turned the RCS thrusters off. If they didn't so this the thrusters would have continued to fire trying to maintain attitude. The remaining items essentially safed the descent engine and 413 in was a command to the AGS (Abort Guidance System) that told the System, they'd landed and to note this position for reference n case of an immediate abort.
If you hadn't noticed, I'm fascinated with the Apollo missions. :)
I recommend the book: "How Apollo flew to the Moon" by W. David Woods for those interested n learning more about the engineering & mechanics of the moon missions.
Clear Skies
Rick Tejera Saguaro Astronomy Club Phoenix, Arizona www.saguaroastro.org [email protected] K7TEJ, AMSAT 38452
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Burns Fisher Sent: Monday, November 14, 2011 15:18 To: [email protected] Subject: [amsat-bb] Apollo 12
... Remember Apollo 12?
Message: 8 Date: Sun, 13 Nov 2011 22:03:01 -0700 From: Rick Tejera [email protected] To: Clint Bradford [email protected] Cc: AMSAT BB [email protected] Subject: [amsat-bb] Re: Would NASA Ever Launch in this Weather? Message-ID: [email protected] Content-Type: text/plain; charset=us-ascii
And mission saved because EECOM controller remembered a test that had the same garbled pattern on his screen. He told the crew (through the Capcom) to "Try SCE to Aux". The NY other person who knew what he meant was LMP Alan Bean. Fortunately the switch was by his head. He flipped it and telemetry was restored.
Among flight controllers the term SCE to Aux is considered legendary.
Btw, SCE stands go Signal Conditioning Equipment. The SCE converts raw signals from instrumentation to standard voltages for the spacecraft instrument displays and telemetry encoders.
Sent from my iPod Rick Tejera Editor, SACnews Saguaro Astronomy Club www.saguaroastro.org K7TEJ
On Nov 13, 2011, at 21:51, Clint Bradford [email protected] wrote:
Touche, Rick. Two lightning strikes ... ABORT handle grasped for minutes
...
Clint
... Remember Apollo 12?
Check out this transcript. Notice that PA makes no mention whatever of the problem? I remember (and actually heard in real time) the "Program Alarm 1201" calls (and was worried before Walter and Wally noticed, as I recall) on Apollo 11, but I don't remember the SCE to Aux call at all. They must have switched it back before TLI, right? Surely they would not head off to the moon with no backup...
Burns, W2BFJ (who also knew they had landed before Walter..."Contact light...engines stop." Wait several seconds, they are still talking. They must have landed!)
http://history.nasa.gov/ap12fj/01launch_to_earth_orbit.htm _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb