Author Topic: Extension decision no closer after “one heck of a year” for shuttle  (Read 31450 times)

Offline Antares

  • ABO^2
  • Senior Member
  • *****
  • Posts: 5201
  • Done arguing with amateurs
  • Liked: 368
  • Likes Given: 226
Yeah...that's my concern.  They don't register on performance, but why aren't they a source of fatigue crack initiation?
Short answer: Don't know. Probable answer is they'd of noted any concern via the flight rationale.

Cracks in a regen wall typically arrest when quite small.  They grow until the fuel leak is enough to drop the wall temperature and lower the stress.
If I like something on NSF, it's probably because I know it to be accurate.  Every once in a while, it's just something I agree with.  Facts generally receive the former.

Offline Lee Jay

  • Elite Veteran
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 6668
  • Liked: 971
  • Likes Given: 139
Yeah...that's my concern.  They don't register on performance, but why aren't they a source of fatigue crack initiation?
Short answer: Don't know. Probable answer is they'd of noted any concern via the flight rationale.

Cracks in a regen wall typically arrest when quite small.  They grow until the fuel leak is enough to drop the wall temperature and lower the stress.

Interesting.  Since there are many sources of stresses on these little tubes, I'm going to have to think about why a lower temperature would alleviate them.

Offline FinalFrontier

  • Senior Member
  • *****
  • Posts: 3920
  • Space Watcher
  • Liked: 327
  • Likes Given: 151
Yeah...that's my concern.  They don't register on performance, but why aren't they a source of fatigue crack initiation?
Short answer: Don't know. Probable answer is they'd of noted any concern via the flight rationale.

Cracks in a regen wall typically arrest when quite small.  They grow until the fuel leak is enough to drop the wall temperature and lower the stress.

Interesting.  Since there are many sources of stresses on these little tubes, I'm going to have to think about why a lower temperature would alleviate them.
Hmm.... When the SSME ignites the nozzle flexes quite a bit very rapidly as the jet comes on and stabilizes. One wonders if the "leaks" could indeed allow the normal process of ignition to actually damage the nozzle (in a serious fashion). But since their tiny...... I guess this is just another minor issue that arises as a result of the shuttles beginning to show their age. Question: Whats the deal with the (shuttle) onboard RCS/OMS and fuel cell hydrolox tanks? I had heard that they were already over the manufacturers specified number of cycles and operating years and that microcracking had been found via Xray scans of the tanks and that this was one very big reason for why the shuttle was being retired. is this true?
« Last Edit: 12/03/2009 04:24 PM by FinalFrontier »
3-30-2017: The start of a great future
"Live Long and Prosper"

Offline Flightstar

  • Lurking around OPF High Bay 2
  • Full Member
  • ****
  • Posts: 1870
  • KSC, Florida
  • Liked: 11
  • Likes Given: 5
Very good article. Needed to be said.

Online Stardust9906

  • Global Moderator
  • Full Member
  • *****
  • Posts: 1260
  • Durham, UK
  • Liked: 20
  • Likes Given: 908
Good article Chris.  Wouldn’t have blamed you if you had decided to point fingers considering the mess things are in right now.


Offline smith5se

Excellent article Chris, and I commend you for not pointing fingers or voicing aggrivation as I sure know I would have.

It's a shame that after such a great year, there's still no word on (what I think) is the backbone of NASA. I'm still hopeful though as this past year proves nay-sayers wrong... Too bad someone couldn't just write up a proposal plan specifically for shuttle extension to congress and be like "look you're taking too long, this is what we want!"
My views are mine, and mine alone and DO NOT reflect that of my employer nor my place of employment.

Offline scotty125

  • Museum Docent/Leicester City Fan
  • Full Member
  • **
  • Posts: 215
  • Portland, Oregon
  • Liked: 1
  • Likes Given: 3
Well done, Chris...another great article.  I for one certainly wouldn't mind if you decided to do an Op-Ed piece every once in a while.  As a non-pro I'd be really interested in the opinions of one much closer to the program than most of us.  Start a new thread, label it as an Op-Ed piece, and let fly.  You might even develop a pseudonym for such activities.;)  You know you want to...:)
"He who will not, when he may, when he should, he shall have nay."
TV Commercial - Gulf Oil during Apollo Landings

Online Chris Bergin

Thanks again :) Nope, not much chance I'd do an op-ed piece - it's a whole different ball game. Much happier reporting quote-based news.

Offline marshallsplace

  • Member
  • Full Member
  • ****
  • Posts: 707
  • UK
    • music website
  • Liked: 0
  • Likes Given: 0
Don't know if this is the correct place for this question but here goes.

With the space shuttle program running towards a probable end without a decision from the leadership.  Is there any probability that the International space powers could and/or would step in to provide support for the SSP?

The SSP has shown that it can support the ISS like no other.  I believe the ISS has a limited life/much reduce capability without the SSP.
   
« Last Edit: 12/04/2009 07:31 PM by marshallsplace »

Offline Analyst

  • Senior Member
  • *****
  • Posts: 3337
  • Liked: 1
  • Likes Given: 7
Short answer: No.

Analyst

Offline marshallsplace

  • Member
  • Full Member
  • ****
  • Posts: 707
  • UK
    • music website
  • Liked: 0
  • Likes Given: 0
Short answer: No.

Analyst

...... yep I know it's a bit of a simplistic, idealistic idea ;)

Offline rdale

  • Assistant to the Chief Meteorologist
  • Senior Member
  • *****
  • Posts: 9893
  • Lansing MI
  • Liked: 240
  • Likes Given: 27
The station can't run without MCC-Houston.

Offline marshallsplace

  • Member
  • Full Member
  • ****
  • Posts: 707
  • UK
    • music website
  • Liked: 0
  • Likes Given: 0
The station can't run without MCC-Houston.

Of course MCC-Houston would be required.  I'm just talking about saving the superior SSP support provided to the ISS.

Offline Jorge

  • Senior Member
  • *****
  • Posts: 6180
  • Liked: 32
  • Likes Given: 0
The station can't run without MCC-Houston.

Of course MCC-Houston would be required.  I'm just talking about saving the superior SSP support provided to the ISS.

Could you try restating your question, then? I think I would have answered the same as rdale. What kind of "support" would the partners provide for the SSP?
JRF

Offline marshallsplace

  • Member
  • Full Member
  • ****
  • Posts: 707
  • UK
    • music website
  • Liked: 0
  • Likes Given: 0
The station can't run without MCC-Houston.

Of course MCC-Houston would be required.  I'm just talking about saving the superior SSP support provided to the ISS.

Could you try restating your question, then? I think I would have answered the same as rdale. What kind of "support" would the partners provide for the SSP?

OK, I was thinking international financial support.  It would mean that NASA would have to accomodate the SSP but be able to follow Constellation.

Offline TheMightyM

  • Member
  • Posts: 69
  • Liked: 7
  • Likes Given: 2
We’re approaching the one-year point of the Obama administration. If there was any enthusiasm for a lengthy extension, we’d have seen it by now. The fact that the answer is “wait for the budget” suggests that the future of HSF is just another rather ordinary decision -- and I doubt that’s good for NASA.

Offline pberrett

  • Full Member
  • **
  • Posts: 256
  • Liked: 0
  • Likes Given: 0
Dear Chris

I am sorry to have to criticize your article but I feel there are some sober reminders to be made here.

"The shuttle has its detractors, even within NASA, citing safety and cost. However, the five flights of 2009 have showed the world just how capable the vehicle is, when cared for by good management and experienced engineering."

Yes the vehicle is capable of hauling a large amount of cargo and crew into LEO but it isn't capable of going beyond that or doing meaningful space exploration.

Further this vehicle has killed 14 Astronauts. That is more that any other space vehicle launched and if there was another accident that would add another 7 coffins.

The vehicle still has no escape system shodul there be an accident on launch and no redundancy of its own shoud the TPS fail. It is a risky,  experimental vehicle that should be grounded as soon as possible in order that a safer replacement can be built.

Accordingto CAIB report (Chapter 1)

"In the end, the greatest compromise NASA made was not so much with any particular element of the technical design, but rather with the premise of the vehicle itself. NASA promised it could develop a Shuttle that would be launched almost on demand and would fly many missions each year. Throughout the history of the program, a gap has persisted between the rhetoric NASA has used to market the Space Shuttle and operational reality, leading to an enduring image of the Shuttle as capable of safely and routinely carrying out missions with little risk."

and

"Despite efforts to improve its safety, the Shuttle remains a
complex and risky system that remains central to U.S. ambitions
in space. Columbia's failure to return home is a harsh
reminder that the Space Shuttle is a developmental vehicle
that operates not in routine flight but in the realm of dangerous
exploration."

It's time to kill the shuttle off and replace it with a safer space transportation system capable of exploration beyond LEO.

Regards Peter



 

Offline vt_hokie

  • Senior Member
  • *****
  • Posts: 3023
  • Hazlet, NJ
  • Liked: 89
  • Likes Given: 214
It's time to kill the shuttle off and replace it with a safer space transportation system capable of exploration beyond LEO.

Sounds good in theory.  I reject the idea, though, that this nation can't afford to develop such a system without retiring the existing system prematurely and then suffering a multi-year gap with no human spaceflight capability.

Online MATTBLAK

  • Elite Veteran & 'J.A.F.A'
  • Senior Member
  • *****
  • Posts: 4265
  • 'Space Cadets' Let us; UNITE!! (crickets chirping)
  • New Zealand
  • Liked: 1068
  • Likes Given: 2029
Dear Chris

I am sorry to have to... Etc...

Regards Peter


No one is saying to extend Shuttle indefinitely, Peter! Least of all me, because I 'grew up' with Shuttle so its, er, 'my' spaceship!! But NOT using the *potential* 2 (or 3) External Tanks and the missions they represent, to me -- and I'm sure others -- is a waste akin to not using the two flightworthy Saturn V's that remained at the end of Apollo. And on a related issue; if the Shuttle-derived infrastructure is lost, then it will be a similar mistake to dumping the Saturn launchers. Variations of this discussion/argument have been around for years and years and this particular thread may not be the place to explore exactly that. But I thought I'd better summarise the issue, at least.
« Last Edit: 12/04/2009 11:56 PM by MATTBLAK »
"Those who can't, Blog".   'Space Cadets' of the World - Let us UNITE!! (crickets chirping)

Tags: