Author Topic: Apollo Q&A  (Read 132565 times)

Offline ugordan

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Re: Apollo Q&A
« Reply #40 on: 08/26/2009 08:20 PM »
The S-IC and S-II stages both had early Center Engine Cutoff (S-II a bit earlier than planned on 13) and I imagine "CECO" would be pronounced the same as "SECO".

Wasn't that called Inboard Engine Cut-off, IECO instead? At least on S-IC.
« Last Edit: 08/26/2009 08:21 PM by ugordan »

Offline psloss

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Re: Apollo Q&A
« Reply #41 on: 08/26/2009 11:20 PM »
The S-IC and S-II stages both had early Center Engine Cutoff (S-II a bit earlier than planned on 13) and I imagine "CECO" would be pronounced the same as "SECO".

Wasn't that called Inboard Engine Cut-off, IECO instead? At least on S-IC.
The call I've heard used "inboard"...there's probably YouTube video available with that sound and the Apollo Flight Journal includes the transcripts for many of the launches.  (For example, Tom Stafford called "inboard shutdown", Neil Armstrong called "inboard cutoff.")
http://history.nasa.gov/afj/

(I need to check in there more often, they've been busy.)

Offline glen4cindy

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Re: Apollo Q&A
« Reply #42 on: 08/27/2009 04:50 AM »
This is the SM-CM umbilical. I am sure it has a fancy name and acronym. It carries power, oxygen, commands etc. between the two modules. You don't want to run these lines through the heat shield and therefore go arround it.

Analyst

Where is this prior to launch?  Is it rotated somehow?  Or under a fairing?  I ask because it does not seem like there would be room for it under the escape tower part that covers the command module. (I forgot the name of it at the moment!)

Thanks.

Offline Jim

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Re: Apollo Q&A
« Reply #43 on: 08/27/2009 05:41 AM »
This is the SM-CM umbilical. I am sure it has a fancy name and acronym. It carries power, oxygen, commands etc. between the two modules. You don't want to run these lines through the heat shield and therefore go arround it.

Analyst

Where is this prior to launch?  Is it rotated somehow?  Or under a fairing?  I ask because it does not seem like there would be room for it under the escape tower part that covers the command module. (I forgot the name of it at the moment!)

Thanks.


Boost cover.

Look on the right side of the modules

http://mediaarchive.ksc.nasa.gov/imageviewer.cfm?mediaid=4523&mr=m&w=572&h=737&fn=ksc-69pc-420&sn=KSC-69PC-420

here too
http://mediaarchive.ksc.nasa.gov/imageviewer.cfm?mediaid=23268&mr=m&w=599&h=754&fn=KSC-69PC-353&sn=KSC-69PC-353

good view here

http://mediaarchive.ksc.nasa.gov/imageviewer.cfm?mediaid=23171&mr=m&w=592&h=744&fn=KSC-69P-247&sn=KSC-69P-247
« Last Edit: 08/27/2009 05:45 AM by Jim »

Offline jhf

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Re: Apollo Q&A
« Reply #44 on: 08/27/2009 08:53 PM »
Thanks for your answers everyone.

sustainer and SECO applies only to classic Atlas

SECO is used by Delta meaning second stage engine cutoff

But the term for SIVB on the Saturn V would be TECO.  SECO would only apply to the Saturn IB

This makes a lot more sense that what I was thinking.  Perhaps someone mistook SECO from a Saturn IB launch as a generic term for S-IVB shutdown; we'll never know.

  Pure oxygen at 5psi is less of an issue than at the 19-some psi on Apollo 1 (14.7 psi + 5-ish).

Apollo 1 was never at 19 psia.  The issue was that is was at 100% O2 at sea level pressure prelaunch, which was suppose to be vented down to 5 psia on orbit.

It seems we're both wrong; Apollo 1 was at 16.7 psia (my understanding is they wanted positive pressure in the spacecraft for the test): http://history.nasa.gov/Apollo204/find.html

Offline Danny Dot

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Re: Apollo Q&A
« Reply #45 on: 08/28/2009 01:31 AM »
  Pure oxygen at 5psi is less of an issue than at the 19-some psi on Apollo 1 (14.7 psi + 5-ish).


Apollo 1 was never at 19 psia.  The issue was that is was at 100% O2 at sea level pressure prelaunch, which was suppose to be vented down to 5 psia on orbit.

It was changed to 60 N2/ 40 O2 , at sea level pressure prelaunch, which was vented down to 100% O2 at 5 psia on orbit.

This may be the first time Jim has been wrong  :-[

Apollo I was a test of the command module.  I am very sure they wanted a 5 psi delta P to test the cabin and pumped the cabin up to 5 above atmospheric to get it. 

What ever the total pressure was, I saw a demo of "burning" lambs wool which was used on the crew seats.  The darn stuff practically went off high order.  It really was close to gasoline in air.

Danny Deger
« Last Edit: 08/28/2009 02:03 AM by Danny Dot »
Danny Deger

Offline Bernard34

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Re: Apollo Q&A
« Reply #46 on: 09/04/2009 06:54 PM »
Hello,
Does anyone explain why during the communication between Apollo and the Houston control each communication start with a "bip" what is the usage of this "Bip
Thanks in advance for a reply
Kind Regards
Bernard
Possible to reply on my email box giann_be@hotmail.com
« Last Edit: 09/05/2009 02:05 PM by Bernard34 »

Online Jorge

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Re: Apollo Q&A
« Reply #47 on: 09/04/2009 07:57 PM »
Hello,
Does anyone explain why during the communication between Apollo and the Houston control each communication start with a "bip" aht is the usage of this "Bip
Kind Regards
Bernard


Google "Quindar tone".
JRF

Offline TJL

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Re: Apollo Q&A
« Reply #48 on: 08/01/2010 01:25 AM »
Can someone identify the "football field size" crater which Armstrong flew over during descent to Tranquility Base?
Thank you...

Offline dks13827

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Re: Apollo Q&A
« Reply #49 on: 08/01/2010 01:35 AM »
 
Apollo 1 was most definately pressurized above atmospheric pressure.   

Since the CM was designed to endure outward pressure in the vacuum of space, the plugs-out test had been run with the cabin pressure at over 16 psi, almost 2 psi above the ambient sea level pressure at Launch Complex 34 and near the upper limits of measuring devices in the spacecraft.

Offline MarsMethanogen

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Re: Apollo Q&A
« Reply #50 on: 08/01/2010 02:14 AM »

Apollo 1 was most definately pressurized above atmospheric pressure.   

Since the CM was designed to endure outward pressure in the vacuum of space, the plugs-out test had been run with the cabin pressure at over 16 psi, almost 2 psi above the ambient sea level pressure at Launch Complex 34 and near the upper limits of measuring devices in the spacecraft.
I may have the units (psi) wrong, but if I recall correctly, the CM was pressurized to 5 psi.  Since the atmosphere in the cabin was pure O2, this was equivalent to the partial pressure of O2 in earth's ambient atmosphere.

Online Jorge

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Re: Apollo Q&A
« Reply #51 on: 08/01/2010 04:15 AM »

Apollo 1 was most definately pressurized above atmospheric pressure.   

Since the CM was designed to endure outward pressure in the vacuum of space, the plugs-out test had been run with the cabin pressure at over 16 psi, almost 2 psi above the ambient sea level pressure at Launch Complex 34 and near the upper limits of measuring devices in the spacecraft.
I may have the units (psi) wrong, but if I recall correctly, the CM was pressurized to 5 psi.

5 psia, in space. But dks13827 is talking about Apollo 1, and he's right. The Apollo 1 plugs-out test was pressurized to 16 psia, a little less than 2 psig.

Quote
  Since the atmosphere in the cabin was pure O2, this was equivalent to the partial pressure of O2 in earth's ambient atmosphere.

Incorrect. PPO2 is around 3 psia.
JRF

Offline billshap

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Re: Apollo Q&A
« Reply #52 on: 09/01/2010 04:39 AM »
Hope someone can help with this. . .During ascent and entry in the Shuttle the CDR and PLT have push-to-talk buttons on their control sticks to open their microphones and transmit voice.  During Apollo, how did the crew key their microphones?  ICOM may have been VOX or hot mic, but A/G was not.  Were there comm control units with push-to-talk buttons in the cables connected to the suits (we see these when they strap in the Shuttle crews and do comm checks)?  Or another set-up? 

Online Jorge

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Re: Apollo Q&A
« Reply #53 on: 09/01/2010 05:03 AM »
Hope someone can help with this. . .During ascent and entry in the Shuttle the CDR and PLT have push-to-talk buttons on their control sticks to open their microphones and transmit voice.  During Apollo, how did the crew key their microphones?  ICOM may have been VOX or hot mic, but A/G was not.  Were there comm control units with push-to-talk buttons in the cables connected to the suits (we see these when they strap in the Shuttle crews and do comm checks)?  Or another set-up? 

Same as shuttle. Both the ACAs on the LM and the RCs on the CM had push-to-talk triggers.
JRF

Offline billshap

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Re: Apollo Q&A
« Reply #54 on: 09/01/2010 05:15 AM »
Thanks for the prompt reply.  I wasn't sure.  How did the LMP transmit?  Did he reach for the RHC in front of the CMP, or did he have another way to key his mic?

Online Jorge

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Re: Apollo Q&A
« Reply #55 on: 09/01/2010 05:35 AM »
Thanks for the prompt reply.  I wasn't sure.  How did the LMP transmit?  Did he reach for the RHC in front of the CMP, or did he have another way to key his mic?

For the CSM, there was a rocker switch on the comm cable that could also be used to key the mike. There's a description in the Apollo Operations Handbook, section 2.8, which can be downloaded at the ALSJ:

http://history.nasa.gov/afj/aohindex.htm

For the LM, of course, each crewmember had his own ACA, plus there was a PTT pushbutton on each crewmember's electrical umbilical. That's described in section 2.7 of the LM AOH:

http://history.nasa.gov/alsj/alsj-LMdocs.html
JRF

Offline billshap

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Re: Apollo Q&A
« Reply #56 on: 09/01/2010 05:44 AM »
Jorge,
Great knowledge, great sources. . .thanks for sharing. 

Offline billshap

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Re: Apollo Q&A
« Reply #57 on: 09/03/2010 09:21 AM »
On Apollo 12 we know the eternally famous "SCE to Aux" call.  Did the call ever go up, and did the crew ever reset the SCE switch to its original setting (PRIMARY, or whatever it was)?  If so, when?  Can't find anything about a reset in the Apollo Flight Journal.

Offline Hungry4info3

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Re: Apollo Q&A
« Reply #58 on: 09/03/2010 01:26 PM »
I recently discovered that the Apollo SM main engine could gimble. I'm curious where the need for this would be, and where/how it was used.

Offline Jim

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Re: Apollo Q&A
« Reply #59 on: 09/03/2010 02:00 PM »
I recently discovered that the Apollo SM main engine could gimble. I'm curious where the need for this would be, and where/how it was used.

The CSM/LM combination mass properties were not symmetrical and so the SME had to gimbal to put the thrust axis thru the CG.

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