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#940
by
Danny Dot
on 06 May, 2008 02:01
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Ronsmytheiii - 2/5/2008 11:56 AM
When there was a Shuttle- skylab program, what would the crew have used as a crew escape vehicle?
snip
The original station concept was the crew would have no way home other than the next Shuttle. Congress said no way and NASA started the Assured Crew Return Vehicle, ACRV, program. ACRV is not needed now because of the use of Soyuz.
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#941
by
Danny Dot
on 06 May, 2008 02:04
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What is the number of the shuttle mission that had the nozzle leak and the Ox low level cut off? Also, can someone provide a link to the copy of the voice loops of what happened in the MCC?
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#942
by
Jorge
on 06 May, 2008 02:20
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Danny Dot - 5/5/2008 9:01 PM
Ronsmytheiii - 2/5/2008 11:56 AM
When there was a Shuttle- skylab program, what would the crew have used as a crew escape vehicle?
snip
The original station concept was the crew would have no way home other than the next Shuttle.
You're talking about Space Station Freedom. He's asking about Skylab.
Shuttle-Skylab planning didn't get very far, but it most likely would have been man-tended, manned only while a shuttle was present.
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#943
by
Jorge
on 06 May, 2008 02:20
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Danny Dot - 5/5/2008 9:04 PM
What is the number of the shuttle mission that had the nozzle leak and the Ox low level cut off?
STS-93.
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#944
by
Danny Dot
on 06 May, 2008 03:16
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Jorge - 5/5/2008 9:20 PM
Danny Dot - 5/5/2008 9:04 PM
What is the number of the shuttle mission that had the nozzle leak and the Ox low level cut off?
STS-93.
Thanks. Now does anyone have a link to the copy of the audio loops in the MCC?
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#945
by
rdale
on 06 May, 2008 03:47
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#946
by
Lawntonlookirs
on 06 May, 2008 15:46
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Once the payload canister arives at the launch pad and is raised up to the white room, what equipment do the have in the white room to unload the payload canister and then reload the cargo into the shuttle? After looking at some pictures from the RSS, it doesn't look like they have much room to move around.
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#947
by
Jim
on 06 May, 2008 16:12
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#948
by
ANDY_WALLACEGROVE
on 06 May, 2008 17:38
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kneecaps - 6/5/2008 12:24 AM
ANDY_WALLACEGROVE - 30/4/2008 2:42 PM
Apologies if this has been asked/answered before;
As the PAO walks us through the last few minutes of launch prep, he has previously referred to the "hundreds" or "thousands" of parameters that will be checked between now and launch.......
my question is, what are these? and where can I find them? I have read the Launch Abort procedures manual more times than is good for my health, but aside the from "pseudo" descriptions which gives crew guidance on the main activities, is there anything more detailed.
Sounds like your referring to the LCCs......Launch Commit Criteria. There are probably thousands, but I'm not aware of a complete list.
Thanks will sniff around L2 to see what I can find....unless anyone else can save me the sniffing?
Note for editor: If I had thought 12 months ago I would have had access to the Launch Abort manual I would have been floored. As it is.....I just want more 
Launch Abort manual? Do you mean the Ascent and Launch Abort manual on L2? Just checking to see if i've missed one 
Thanks, it is Ascent and Launch Abort. Read it so many times, but obviously not the front cover :-)
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#949
by
Lawntonlookirs
on 06 May, 2008 18:49
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#950
by
mkirk
on 06 May, 2008 22:16
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kneecaps - 5/5/2008 6:24 PM
ANDY_WALLACEGROVE - 30/4/2008 2:42 PM
Apologies if this has been asked/answered before;
As the PAO walks us through the last few minutes of launch prep, he has previously referred to the "hundreds" or "thousands" of parameters that will be checked between now and launch.......
my question is, what are these? and where can I find them? I have read the Launch Abort procedures manual more times than is good for my health, but aside the from "pseudo" descriptions which gives crew guidance on the main activities, is there anything more detailed.
Sounds like your referring to the LCCs......Launch Commit Criteria. There are probably thousands, but I'm not aware of a complete list.
The GLSDD (ground launch sequencer description document) has a list of the parameters. The only elctronic copy that I have is from the STS-96 timeframe but I will dig it out and and give it to Chris to post. I am traveling so give me some time to return home and I will get it posted.
I warn you that this document is not really descriptive as the title implies, it simply lists parameters and sequences with their assigned values or limits. It is not "reader friendly" for the lay person.
Mark Kirkman
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#951
by
Lindsay
on 06 May, 2008 22:26
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If there is a cutoff after T-31 seconds and the issue is quickly resolved and there is a large launch window, would it be possible in theory to pick up the count again from T-20 minutes without having to scrub the launch?
This post suggests it can't be done:
mkirk 22/8/2006 11:43 PM
If you pass T-31 seconds only cutoff is available and you are done for the day. The recycle to T-20 minutes serves as the staring point for whatever scrub option is chosen.
This post suggets it can be done:
jcopella 24/7/2006 7:55 AM
You don't want to go past T-31 seconds because any failures or a request to hold after that point result in GLS cutoff and safing, which means (at least) a recycle back to T-20 minutes, if not an outright scrub for the day.
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#952
by
mkirk
on 06 May, 2008 22:32
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Lindsay - 6/5/2008 5:26 PM
If there is a cutoff after T-31 seconds and the issue in quickly resolved and there is a large launch window, would it be possible in theory to pick up the count again from T-20 minutes without having to scrub the launch?
This post suggests it can't be done:
mkirk 22/8/2006 11:43 PM
If you pass T-31 seconds only cutoff is available and you are done for the day. The recycle to T-20 minutes serves as the staring point for whatever scrub option is chosen.
This post suggets it can be done:
jcopella 24/7/2006 7:55 AM
You don't want to go past T-31 seconds because any failures or a request to hold after that point result in GLS cutoff and safing, which means (at least) a recycle back to T-20 minutes, if not an outright scrub for the day.
You can HOLD at T-31, if you pass T-31 then only "CUTOFF" is available. A CUTOFF means you are done for the day, the team will recycle to T-20 minutes to get the spacecraft and ground support equipment in a safe configuration and then they will scrub the launch (no matter how much time is left in the window) by initiating the appropriate scrub sequences.
Currently the ISS launch windows are so short that a second attempt would not really be an option anyway.
Mark Kirkman
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#953
by
mkirk
on 06 May, 2008 22:43
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Lindsay - 6/5/2008 5:35 PM
mkirk - 6/5/2008 11:32 PM
You can HOLD at T-31, if you pass T-31 then only "CUTOFF" is available. A CUTOFF means you are done for the day, the team will recycle to T-20 and scrub the launch no matter how much time is left in the window.
Mark Kirkman
Is there any technical reason why they can't pick up again from T-20 or is it just in the rules?
My best guess is that the answer to that question is both.
It is a rule but for the most part the technical reasons come into play the farther you go beyond T-31. For Instance if you get in the T-20 second timeframe the SRB hydraulic power units are started so you are burning valuble fuel (which is very limited for the HPUs) and I think there are ground crew inpection requirements before they could be restarted again for another launch attempt even if you saved enough fuel by shutting them down.
Another obvious example would be if you got beyond T-10 seconds and fire the ROFI (i.e. the hydrogen burnoff flares), new ordnance would have to be installed. I believe we had that with one of the initial launch attempts for STS-93.
Mark Kirkman
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#954
by
Lindsay
on 06 May, 2008 22:48
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mkirk - 6/5/2008 11:43 PM
My best guess is that the answer to that question is both. It is a rule but for the most part the technical reasons come into play the farther you go beyond T-31. For Instance if you get in the T-20 second timeframe the SRB hydraulic power units are started so you are burning valuble fuel (which is very limited for the HPUs) and I think there are ground crew inpection requirements before they could be restarted again for another launch attempt.
Another obvious example would be if you got beyond T-10 seconds and fire the ROFI (i.e. the hydrogen burnoff flares), new ordnance would have to be installed. I believe we had that with one of the initial launch attempts for STS-93.
Mark Kirkman
I was just thinking of Apollo 17 (countdown was cutoff at T-30 seconds, recycled to T-22 minutes then launched).
Thanks for the replies.
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#955
by
Jim
on 06 May, 2008 22:52
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Lindsay - 6/5/2008 6:26 PM
If there is a cutoff after T-31 seconds and the issue in quickly resolved and there is a large launch window, would it be possible in theory to pick up the count again from T-20 minutes without having to scrub the launch?
This post suggests it can't be done:
mkirk 22/8/2006 11:43 PM
If you pass T-31 seconds only cutoff is available and you are done for the day. The recycle to T-20 minutes serves as the staring point for whatever scrub option is chosen.
This post suggets it can be done:
jcopella 24/7/2006 7:55 AM
You don't want to go past T-31 seconds because any failures or a request to hold after that point result in GLS cutoff and safing, which means (at least) a recycle back to T-20 minutes, if not an outright scrub for the day.
Done for longer than a day. SRB HPU's would need to be reserviced
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#956
by
mkirk
on 06 May, 2008 23:15
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Lindsay - 6/5/2008 5:48 PM
I was just thinking of Apollo 17 (countdown was cutoff at T-30 seconds, recycled to T-22 minutes then launched).
Thanks for the replies.
Apollo was obviously a different animal and the rules and use of the terms cutoff and hold were slightly different than for shuttle.
The Apollo Auto Sequence started at T-3 minutes 7 Seconds and any time the count was stopped after that time it was termed a "cutoff" since they were terminating the auto sequence.
The rules back then dictated a recycle to T-22 minutes to either hold the count and repair the problem or scrub the launch. Theoretically, after T-11 seconds, as long as the "auto cutoff" took place prior to engine ignition the launch team could recycle to T-22 minutes and depending on the nature of the problem and the duration of the launch window a second launch attempt was still possible.
I used the term auto cutoff because after T-11 seconds manual cutoffs were not an option unless ignition failed to occur for some reason.
Mark Kirkman
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#957
by
ChrisGebhardt
on 07 May, 2008 03:58
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Jim - 6/5/2008 6:52 PM
Lindsay - 6/5/2008 6:26 PM
If there is a cutoff after T-31 seconds and the issue in quickly resolved and there is a large launch window, would it be possible in theory to pick up the count again from T-20 minutes without having to scrub the launch?
This post suggests it can't be done:
mkirk 22/8/2006 11:43 PM
If you pass T-31 seconds only cutoff is available and you are done for the day. The recycle to T-20 minutes serves as the staring point for whatever scrub option is chosen.
This post suggets it can be done:
jcopella 24/7/2006 7:55 AM
You don't want to go past T-31 seconds because any failures or a request to hold after that point result in GLS cutoff and safing, which means (at least) a recycle back to T-20 minutes, if not an outright scrub for the day.
Done for longer than a day. SRB HPU's would need to be reserviced
The second launch attempt for STS-61C on December 19, 1985 had a cutoff at T-14secs due to an indication that the right SRB HPU was exceeding the RPM redline speed limits. Even though this was later shown to be a false reading, it resulted in an 18day delay to the next attempt. I'm not sure how much of this time was directly related to HPU reservicing giving the Christmas/New Year's holiday season but it still serves as an example of a cutoff after SRB HPU activiation.
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#958
by
psloss
on 07 May, 2008 10:27
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Trekkie07 - 6/5/2008 11:58 PM
The second launch attempt for STS-61C on December 19, 1985 had a cutoff at T-14secs due to an indication that the right SRB HPU was exceeding the RPM redline speed limits. Even though this was later shown to be a false reading, it resulted in an 18day delay to the next attempt. I'm not sure how much of this time was directly related to HPU reservicing giving the Christmas/New Year's holiday season but it still serves as an example of a cutoff after SRB HPU activiation.
The holidays was the stated reason at the time (and probably some troubleshooting to isolate the problem).
There have been a couple of other cases that resulted in 48-hour recycles -- the STS-93 cutoff and the "breakout" in the STS-56 count that stopped at T-11.
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#959
by
Lawntonlookirs
on 07 May, 2008 19:53
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I am still having a problem finding information on the PCR and the PGHM. Do we have any pictures that show the PGHM in operation?
