Author Topic: ISS managers working to realign busy launch manifest following ongoing delays  (Read 25186 times)

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17940
  • Westphal, Nova Scotia
  • Liked: 661
  • Likes Given: 7801
Great article Pete. I didn't know they were thinking of moving the other EVA up to Feb 2013. I have a few theories though...

Please share, because I don't have any info. The only reason I can think of for having two EVAs so close together is that they might be getting ready to relocate the PMM, Cupola & PMA-3.


copying over content from a locked thread:

http://forum.nasaspaceflight.com/index.php?topic=24433.msg715523#msg715523

Quote from: Chris Bergin on 03/29/2011 05:32 PMAnother meaty FRR-based article from Chris G:

NASA Reviews New Procedures for STS-134/Endeavour Mission - by Chris Gebhardt:

http://www.nasaspaceflight.com/2011/03/nasa-new-procedures-sts-134-mission/
----------------------------------

Nice.

Of course I have to point this one out (which I read about on L2, and was hoping it came out on the public side - thanks Chris):

'As noted by the MOD presentation from the Flight Director, “2B PVTCS has a slow ammonia leak that will eventually result in loss of 2B cooling. Tasks on EVA 1 and EVA 2 configure cooling systems (ETCS/EETCS/PVTCS) to fill the 2B PVTCS using ammonia from the Loop B ATA.” '

Something to discuss on the ISS thread, commercial shuttle, and possibly include on the HLV block 0 payloads thread as required: The need for ISS logistics support in the long run, and perhaps sooner ;)

Online Chris Bergin

Might be fun to bump L2 presentations of reference, Robert. No biggy, but always worth a reread.
Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline arkaska

  • Senior Member
  • *****
  • Posts: 3042
  • Sweden
  • Liked: 1
  • Likes Given: 4
But to be fair, ISS was still facing the same reliability problems with Soyuz before Shuttle retired. If Soyuz was grounded for some reason ISS would be de-crewed no matter if Shuttle was flying or not. So the debate over Russian reliability in conduction with Shuttle retirement is a bit misdirected in my opinion.


Soyuz was always critical to ISS, that much is true.  However, a grounding of Soyuz did not immediately mean abandoning the ISS.

Depending on the nature of the failure there were several possibilities.  There would be at least one, possibly two, Soyuz up there already and would have, eventually, needed to be flown home.

With Shuttle in the mix, crews could have been rotated on the orbiter while keeping one or two Soyuz still there (and evaluating them for any life extension, etc)

At the very worse, if ISS had to be de-crewed from a constant presense, Shuttle allowed a man-tended capability for up to two or so weeks at a time. 

Without shuttle, there is one fundamental truth.  We are totally reliant on the Russians

But Soyuz life-time is still only about 1 year, how much extension could they possibly make on-orbit? I think this is a bigger and longer running problem then the Shuttle retirement. I was a big mistake to cancel the CRV without a replacement planned. Maybe they should have started commercial crew earlier, the need still existed before Shuttle retired as the Shuttle couldn't bring up long term crew members without relying on Soyuz for emergency return.

Offline arkaska

  • Senior Member
  • *****
  • Posts: 3042
  • Sweden
  • Liked: 1
  • Likes Given: 4
They have said they won't reduce the crew but the science conducted up there will be greatly reduced. No new science will be flown and only essential equipment will be flown on Progress.

There is no guarantee crew will not be reduced and the "science" is already being impacted by not having a transportation method there. 

Remember Shuttle was to provide much of that.  Progress, ATV and HTV were to augment shuttle.  There has been no change in the frequency of these flights to help fill the gap created by loss of shuttle. 

I guess I'm a bit cynical and not as concerned as I maybe should be. However, until the years end I do not think science is affected to much because of delayed commercial. Except in one case, down mass, which is a huge concern.

And I don't think Dragon can make up for all that. Especially the ability to bring down entire racks if the need be.

(and let's not even go to external ORUs)

Offline arkaska

  • Senior Member
  • *****
  • Posts: 3042
  • Sweden
  • Liked: 1
  • Likes Given: 4

copying over content from a locked thread:

http://forum.nasaspaceflight.com/index.php?topic=24433.msg715523#msg715523

Quote from: Chris Bergin on 03/29/2011 05:32 PMAnother meaty FRR-based article from Chris G:

NASA Reviews New Procedures for STS-134/Endeavour Mission - by Chris Gebhardt:

http://www.nasaspaceflight.com/2011/03/nasa-new-procedures-sts-134-mission/
----------------------------------

Nice.

Of course I have to point this one out (which I read about on L2, and was hoping it came out on the public side - thanks Chris):

'As noted by the MOD presentation from the Flight Director, “2B PVTCS has a slow ammonia leak that will eventually result in loss of 2B cooling. Tasks on EVA 1 and EVA 2 configure cooling systems (ETCS/EETCS/PVTCS) to fill the 2B PVTCS using ammonia from the Loop B ATA.” '

Something to discuss on the ISS thread, commercial shuttle, and possibly include on the HLV block 0 payloads thread as required: The need for ISS logistics support in the long run, and perhaps sooner ;)

IIRC when they topped up the PVTCS is was less then 10 pounds of ammonia required. So I do not think there is a need to replace it (or they would have addressed it already) and I think they mentioned something like 2-3 years between topping it off. So I do not think any of the upcoming EVAs will deal with this.

Offline Namechange User

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 7301
  • Liked: 0
  • Likes Given: 0
But Soyuz life-time is still only about 1 year, how much extension could they possibly make on-orbit? I think this is a bigger and longer running problem then the Shuttle retirement. I was a big mistake to cancel the CRV without a replacement planned. Maybe they should have started commercial crew earlier, the need still existed before Shuttle retired as the Shuttle couldn't bring up long term crew members without relying on Soyuz for emergency return.

If I recall correctly, the Soyuz on-orbit life is approximately 6-7 months.  I find it hard to believe that on one day it is perfectly acceptable to come home, on the next it means certain death. 

While there would need to be evaluations and this would have to happen on short-order I really don't expect such a steep cliff. 

While I agree CRV cancellation drove us to Soyuz-only for CRV, the retirement of Shuttle placed us even more in bed with the Russians and took away *all* options for the most part. 
« Last Edit: 02/08/2012 11:10 pm by OV-106 »
Enjoying viewing the forum a little better now by filtering certain users.

Offline Namechange User

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 7301
  • Liked: 0
  • Likes Given: 0
I guess I'm a bit cynical and not as concerned as I maybe should be. However, until the years end I do not think science is affected to much because of delayed commercial. Except in one case, down mass, which is a huge concern.

And I don't think Dragon can make up for all that. Especially the ability to bring down entire racks if the need be.

(and let's not even go to external ORUs)

I know there were potential job opportunities on ISS Program that have been cancelled or put on hold due to payloads not being able to fly. 

Take that as you will. 
Enjoying viewing the forum a little better now by filtering certain users.

Offline AnalogMan

  • Member
  • Senior Member
  • *****
  • Posts: 3450
  • Cambridge, UK
  • Liked: 1632
  • Likes Given: 55


As noted by the MOD presentation from the Flight Director, “2B PVTCS has a slow ammonia leak that will eventually result in loss of 2B cooling. Tasks on EVA 1 and EVA 2 configure cooling systems (ETCS/EETCS/PVTCS) to fill the 2B PVTCS using ammonia from the Loop B ATA.” '

Something to discuss on the ISS thread, commercial shuttle, and possibly include on the HLV block 0 payloads thread as required: The need for ISS logistics support in the long run, and perhaps sooner ;)

IIRC when they topped up the PVTCS is was less then 10 pounds of ammonia required. So I do not think there is a need to replace it (or they would have addressed it already) and I think they mentioned something like 2-3 years between topping it off. So I do not think any of the upcoming EVAs will deal with this.

I had a quick look at the SSP FRR Flight Directors Office presentation (dated March 31, 2011) which noted that the slow leak, as it existed then, gave a predicted loop B shutdown in April 2013 (an interval of 24 months).  It does not say how long it had been leaking up to the point of the FRR, but a 2-3 year topping off interval seems plausible.  This would place the next top-up between May 2013 and May 2014.

Offline robertross

  • Canadian Member
  • Senior Member
  • *****
  • Posts: 17940
  • Westphal, Nova Scotia
  • Liked: 661
  • Likes Given: 7801
Might be fun to bump L2 presentations of reference, Robert. No biggy, but always worth a reread.
done

(I was also hurried at the time)



As noted by the MOD presentation from the Flight Director, “2B PVTCS has a slow ammonia leak that will eventually result in loss of 2B cooling. Tasks on EVA 1 and EVA 2 configure cooling systems (ETCS/EETCS/PVTCS) to fill the 2B PVTCS using ammonia from the Loop B ATA.” '

Something to discuss on the ISS thread, commercial shuttle, and possibly include on the HLV block 0 payloads thread as required: The need for ISS logistics support in the long run, and perhaps sooner ;)

IIRC when they topped up the PVTCS is was less then 10 pounds of ammonia required. So I do not think there is a need to replace it (or they would have addressed it already) and I think they mentioned something like 2-3 years between topping it off. So I do not think any of the upcoming EVAs will deal with this.

I had a quick look at the SSP FRR Flight Directors Office presentation (dated March 31, 2011) which noted that the slow leak, as it existed then, gave a predicted loop B shutdown in April 2013 (an interval of 24 months).  It does not say how long it had been leaking up to the point of the FRR, but a 2-3 year topping off interval seems plausible.  This would place the next top-up between May 2013 and May 2014.

True enough, although as you mention "as it existed then". It was the one that first came to mind as to the reason they may wish to move up a US EVA.

A Second one is the LEE snare fraying they have recently noticed. I'd have to look up if they actually require an EVA to do a change-out, but I'm thinking yes, specifically for the thermal covers, and also any hold-down bolts holding it down onto the ESP.

The last thought would be the other Ammonia Pump Module, but there is insufficient  time available to do a swap. (ref: the GAO report indicated a revised MTBF of ~6-1/2 years, and depending on when the S1/P1 Trusses with the Pump Modules, installed 2002, were activated with the Solar Arrays, starting around 2006, we could be approaching that time, considering the failed PM is being looked at)

Offline JimOman

First off, great article!!! This level of detail is why I read this site daily.

A few quick questions-

1) Which EVA (R31 or US 18) will R&R the MBSU?

2) I'm assuming it is US EVA 18, and if so, what will Russian EVA 31 do?

Thanks- Jim
NASA National Collegiate Aerospace Scholars, 2010
CSE Student Rep, Congress 2012, 13, 14

Offline alexw

  • Full Member
  • ****
  • Posts: 1230
  • Liked: 4
  • Likes Given: 2
People need to acknowledge we are in a strategically bad position with respect to ISS.  Everyone said get rid of Shuttle because the Russians do not have any "problems" and "commercial" was just around the corner supposedly. 
...
ISS is suffering and people should not try to gloss over that and spin the situation. 
    Everyone did *not* say that, and this sounds like a retro-historical strawman. There were compelling reasons to retire Shuttle even while knowing full well that the Russians are hardly infallible and that the commercial providers chosen -- SpaceX and Orbital and Kistler -- were all unproven at the scales required. Very unproven, even. It was a calculated risk. You may regard that risk as excessive and unnecessary, even foolhardy, of course.

NASA have said that commercial need to get up and running this year in order for station to continue six crew operations next year.
[...]
Maybe I'm being over dramatic, but whether I am or am not, the worst part of it is, this is all just so unnecessary - if we'd kept Shuttle around until 2014, we could have reduced all the risk on ISS from commercial failures, and allowed them to get fully up & running before handing them the keys.
      Pete, there are two tacit assumptions in that statement: that keeping six crew on ISS at (almost) all times is a high or highest priority, and that keeping Shuttle carried little opportunity cost.

    I realize that this is a very different world-view, and perhaps uncomfortably controversial. I do not mean to be offensive or flippant. But it is possible to have -- and many do -- a very different sense of balancing the costs and risks and benefits and priorities of six-crew ISS, ISS science, flying Shuttle, promising-but-unproven new providers of launch vehicles and space flight vehicles, defense contractors, and all the other elements wrapped up in HSF and spaceflight more generally. 

    It's not necessarily "glossing over", or "spin" -- one can have a fundamentally different world view of priorities. If you're interested, we can continue and discuss that.
       -Alex

Offline alexw

  • Full Member
  • ****
  • Posts: 1230
  • Liked: 4
  • Likes Given: 2
Thanks for all the nice comments guys, glad you enjoyed it. I myself was thinking that ISS manifests might slow down after Shuttle....how wrong I was! :)
BTW, this article really is packed with remarkable detail. One needs an annotated timeline to keep track of it all!
For that, I recommend anik's excellent schedule:
http://forum.nasaspaceflight.com/index.php?topic=61
     Excellent indeed, thank you.
                       -Alex

Offline anik

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 7776
  • Liked: 955
  • Likes Given: 368
1) Which EVA (R31 or US 18) will R&R the MBSU?

US EVA-18.

2) I'm assuming it is US EVA 18, and if so, what will Russian EVA 31 do?

Relocation of GStM-2 cargo boom from Pirs module to Zarya module and installation of Obstanovka experiment on Zvezda module.

Online dsmillman

  • Member
  • Full Member
  • ****
  • Posts: 1489
  • Liked: 356
  • Likes Given: 30
In the STS-116 EVA checklist there are contingencies EVA's to R&R the MBSU's.  They are listed as follows:

MBSU REMOVE AND REPLACE – 2A2B
MBSU REMOVE AND REPLACE – 3A3B
MBSU REMOVE AND REPLACE – 1A1B
MBSU REMOVE AND REPLACE – 4A4B

Which one of these is the MBSU-1 mentioned in article?

Offline AnalogMan

  • Member
  • Senior Member
  • *****
  • Posts: 3450
  • Cambridge, UK
  • Liked: 1632
  • Likes Given: 55
In the STS-116 EVA checklist there are contingencies EVA's to R&R the MBSU's.  They are listed as follows:

MBSU REMOVE AND REPLACE – 2A2B
MBSU REMOVE AND REPLACE – 3A3B
MBSU REMOVE AND REPLACE – 1A1B
MBSU REMOVE AND REPLACE – 4A4B

Which one of these is the MBSU-1 mentioned in article?

According to the attached schematic MBSU-1 controls the feeds from solar arrays 1A and 1B (S4 and S6 trusses respectively).

Offline psloss

  • Veteran armchair spectator
  • Senior Member
  • *****
  • Posts: 17995
  • Liked: 4069
  • Likes Given: 2117
I had a quick look at the SSP FRR Flight Directors Office presentation (dated March 31, 2011) which noted that the slow leak, as it existed then, gave a predicted loop B shutdown in April 2013 (an interval of 24 months).  It does not say how long it had been leaking up to the point of the FRR, but a 2-3 year topping off interval seems plausible.  This would place the next top-up between May 2013 and May 2014.
In the preflight mission briefing for ULF-6, Derek Hassmann said that if the leak persisted it would need to be reserviced periodically; however, he said that the ammonia re-fill/top off on ULF-6 would "extend the life...ideally, if the fill goes well, we're going to extend the life a number of years."

Offline JimOman

1) Which EVA (R31 or US 18) will R&R the MBSU?

US EVA-18.

2) I'm assuming it is US EVA 18, and if so, what will Russian EVA 31 do?

Relocation of GStM-2 cargo boom from Pirs module to Zarya module and installation of Obstanovka experiment on Zvezda module.


Thanks for the clarification, Anik!
NASA National Collegiate Aerospace Scholars, 2010
CSE Student Rep, Congress 2012, 13, 14

Offline AnalogMan

  • Member
  • Senior Member
  • *****
  • Posts: 3450
  • Cambridge, UK
  • Liked: 1632
  • Likes Given: 55
Great summary of this years schedule.

Now I might start to dream again about a new FPWG manifest  :D

Thought you might be interested in this version dated March 3, 2012

Offline Space Pete

Thought you might be interested in this version dated March 3, 2012

Some nice little tidbits in there.

Firstly, we could be looking at another HTV-3 relocation to Node 2 Zenith should that flight conflict with any commercial flights.

Secondly, we now know the external payloads for HTV-4, SpX-2 and SpX-3.

HTV-4: MBSU (Main Bus Switching Unit), UTA (Utility Transfer Assembly), STP-H4 (Space Test Program-Houston 4).

SpX-2: HRSGF - I suspect this is the item shown in the image attached below. I have said before that I think this is some kind of grapple bar for the ISS radiators - well, HRS is Heat Rejection Subsystem, and GF could be Grapple Fixture. Just a guess though.

SpX-3: HDEV (unknown), OPALS (Optical PAyload for Lasercomm Science), NOFBX (Nitrous Oxide Fuel Blend).
« Last Edit: 03/18/2012 12:56 pm by Space Pete »
NASASpaceflight ISS Writer

Offline Dappa

  • Full Member
  • ****
  • Posts: 1867
  • the Netherlands
  • Liked: 62
  • Likes Given: 76
Thought you might be interested in this version dated March 3, 2012
What's going on with 47P July 22 and July 24? Is that an undocking and redocking or am I misinterpreting something?

Tags:
 

Advertisement NovaTech
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
1