NASA's New 'Lesson' from Space

[Brian Thorn]

There really haven't been an outrageous number of repairs on the station. It's not like every mission to the Station is going up just to fix something that broke, most of the spacewalks have been to install new hardware (like the S5 Truss on this mission), hook up cables, that sort of thing.

The Control Moment Gyros like the one (of four) replaced this week have been particularly problematical, but they're high speed gyros that have been spinning more or less constantly since 2000, and NASA always knew they'd have to replace them from time to time (that's why they're relatively easy to get to and replace.) Parts that run all the time will eventually wear out. There's nothing magical about spaceflight that gets around this fact of life.

Brian

[Fred J. McCall]

:On Sat, 18 Aug 2007 10:35:35 -0700, Fred J. McCall : wrote: : : :>ISS isn't a car. It's a house. When was the last time you had to :>call in a repair crew to replace a part of your house that was only 7 :>years old? : :You never had to work on your house in seven years? Where do you live :and how can I get one like it? Home Depot and Lowe's must really hate :whoever built your house! :

Pretty much not, yeah. I think the first 7 years ought to be pretty damned much 'no care required'. We're not talking about a 30 year old house here. ISS is *NEW*.

The only 'work' I've had done other than 'trim the trees' is to put more refrigerant in the air conditioner. I haven't had to call anyone in to replace pieces, particularly pieces that are only 7 years old.

[Michael Bulatovich]

Be that as it may, these guys make odds that generally win for themselves. My (uninformed) sense is that shuttle missions have been meeting with more regular damage requiring repairs or burials than when the vehicles were new. Most of them have around the same mileage, don't they?

[Rand Simberg]

On Sat, 18 Aug 2007 16:43:33 -0400, in a place far, far away, "Michael Bulatovich" made the phosphor on my monitor glow in such a way as to indicate that:

No, they haven't. It's actually less, but they can't reduce it to zero. The only reason that it seems like more now is because we're paying a lot more attention to it than we used to.

And the "mileage" of the orbiters is irrelevant. The problem is caused by the external tanks, which are new every flight, since they must be expended.

[Michael Bulatovich]

What about the tiles?

[Alan Anderson]

What about them? They're the *victims* of the damage, not the cause.

[Rand Simberg]

On Sat, 18 Aug 2007 17:41:34 -0400, in a place far, far away, "Michael Bulatovich" made the phosphor on my monitor glow in such a way as to indicate that:

They are inspected every flight, and replaced, if necessary. Again, it has nothing to do with "mileage."

[Fred J. McCall]

:>>Be that as it may, these guys make odds that generally win for themselves. :>>My (uninformed) sense is that shuttle missions have been meeting with more :>>regular damage requiring repairs or burials than when the vehicles were :>>new. :>>Most of them have around the same mileage, don't they? :>>

:>

:> No, they haven't. It's actually less, but they can't reduce it to :> zero. The only reason that it seems like more now is because we're :> paying a lot more attention to it than we used to. :>

:> And the "mileage" of the orbiters is irrelevant. The problem is :> caused by the external tanks, which are new every flight, since they :> must be expended. : :What about the tiles? :

What about them? They're inspected after every flight and any that show any wear are replaced.

There's never been an issue due to 'tile wear'.

[Fred J. McCall]

:>>>Be that as it may, these guys make odds that generally win for :>>>themselves. :>>>My (uninformed) sense is that shuttle missions have been meeting with :>>>more :>>>regular damage requiring repairs or burials than when the vehicles were :>>>new. :>>>Most of them have around the same mileage, don't they? :>>

:>> No, they haven't. It's actually less, but they can't reduce it to :>> zero. The only reason that it seems like more now is because we're :>> paying a lot more attention to it than we used to. :>>

:>> And the "mileage" of the orbiters is irrelevant. The problem is :>> caused by the external tanks, which are new every flight, since they :>> must be expended. :>>

:>

:> What about the tiles? :>

: :What about the *stuff* that keeps coming off and effecting the tiles? :

That 'stuff' is new with every flight. Any tiles that take damage are replaced with new ones after every flight.

So tell us again how 'mileage' on the Shuttle somehow matters...

[Fred J. McCall]

:> There's never been an issue due to 'tile wear'. :>

: :Has it been shown that the stuff that causes faults in the exterior, like :the current incident for example, NOT been tiles? :

Of course it has! Jesus, what ignorant rock do you hide under?

The 'stuff' isn't tiles. It's foam off the external tank. This has been known for years. Where have you been?

[Michael Bulatovich]

Well..... to use an analogy in this field, consider door casings. Besides the function of covering joints between materials, it can be argued that one of their functions is to protect a buildings' more fragile interior finish at the places where mechanical abrasion is more likely....at door and window openings.

In doing this, over extended periods, a degradation of the condition of these elements is normal and expected. You could argue that the "cause" of the damage is not the casings themselves but the movement of people and goods through the opening, but the effect is the same. The materials and their attachment can be weakened without immediate, obvious visual evidence of that fact. They also get obviously banged up progressively, and eventually bits start to come off, especially when we start moving furniture. These casings can be hardwood, softwood, even stone or metal, and each material will degrade at different rates and in slightly different ways.

I never said the tiles were the *cause* of any damage, and have heard the explanations regarding tank insulation, but find it very hard to imagine that the tiles (which I recall thinking were a dicey idea when I first saw them) do not suffer any cumulative degradation from repeated exposures to the kinds of stresses they experience. Ditto for their attachment. I also know nothing of the inspection regimen, but imagine that it is primarily visual, which could fail to detect 'invisible' defects or wear.

[Brian Thorn]

It is foam insulation from the External Tank. This was widely reported following the Columbia accident in 2003.

NASA has already reduced foam shedding from the External Tank by well over 90% since Columbia. The places where foam has been falling off the worst are the nooks and crannies, the little bumps and crevaces in the structure of the Tank that are hard to model in a computer... the bipod ramp lost foam that caused the Columbia accident. Return to Flight lost a big chunk of the PAL ramp but caused no damage. NASA has been working on changing the Ice/Frost Ramps. The support brackets on the Liquid Oxygen feed line have caused problems on the last two flights.

A major impact on the tiles is going to cause damage. It doesn't matter if it is an aging tile from 1984 or one factory-fresh.

Brian

[jcon]

If you think alcoholism and emotional immaturity preclude science, you haven't known a lot of scientists, so I'm willing to cut them some slack on that one :)

I'm more worried that after 35+ years of "space science", about 95% of the experiments are still described as "studying the effects of zero gravity on XXX". The CAM (Centrifuge Accommodations Modules) could have even added some science to *that*, by allowing them to control small amounts of gravity - but of course that was canceled so there'd be plenty of money to launch teachers and such.

-jc

[BradGuth]

That our astronauts and spendy shuttles are totally expendable. They should just thank their lucky stars that none of our ABLs are allowed to be running through those R&D trials, as required per DoD field testing in order to qualify for their next level of funding.

However, any extended EVAs are also damn risky business, whereas at least our frail DNA isn't a happy camper to all of that raw solar and moon contributed radiation, not to mention their having to avoid that nasty Van Allen SAA contour that's getting extremely large.

Perhaps of whatever's on the backside of that broken set of thermal tiles isn't all that mission critical.

- Brad Guth

[Fred J. McCall]

:> :>>>Be that as it may, these guys make odds that generally win for :> :>>>themselves. :> :>>>My (uninformed) sense is that shuttle missions have been meeting with :> :>>>more :> :>>>regular damage requiring repairs or burials than when the vehicles were :> :>>>new. :> :>>>Most of them have around the same mileage, don't they? :> :>>

:> :>> No, they haven't. It's actually less, but they can't reduce it to :> :>> zero. The only reason that it seems like more now is because we're :> :>> paying a lot more attention to it than we used to. :> :>>

:> :>> And the "mileage" of the orbiters is irrelevant. The problem is :> :>> caused by the external tanks, which are new every flight, since they :> :>> must be expended. :> :>>

:> :>

:> :> What about the tiles? :> :>

:> : :> :What about the *stuff* that keeps coming off and effecting the tiles? :> : :>

:> That 'stuff' is new with every flight. Any tiles that take damage are :> replaced with new ones after every flight. :>

:> So tell us again how 'mileage' on the Shuttle somehow matters... : :I never mentioned *mileage*. :

So you merely took the side of the guy who did.

Same difference...

[Fred J. McCall]

:> :> There's never been an issue due to 'tile wear'. :> :>

:> : :> :Has it been shown that the stuff that causes faults in the exterior, like :> :the current incident for example, NOT been tiles? :> : :>

:> Of course it has! Jesus, what ignorant rock do you hide under? :>

:> The 'stuff' isn't tiles. It's foam off the external tank. This has :> been known for years. Where have you been? : :It was a simple yes or no question. :

Simple question from a simple source, I guess...

: :But you decided to get emotional about it. :

Don't be a bigger idiot than you already have shown yourself. I've been on Usenet for decades. A bit late to get 'emotional' now.

Just another 'Stupid Usenet Tricks 101' tactic on your part - "When you're at a loss, accuse the other guy of emotionalism or losing his temper"...

[Fred J. McCall]

:> :> :>>>Be that as it may, these guys make odds that generally win for :> :> :>>>themselves. :> :> :>>>My (uninformed) sense is that shuttle missions have been meeting :> with :> :> :>>>more :> :> :>>>regular damage requiring repairs or burials than when the vehicles :> were :> :> :>>>new. :> :> :>>>Most of them have around the same mileage, don't they? :> :> :>>

:> :> :>> No, they haven't. It's actually less, but they can't reduce it to :> :> :>> zero. The only reason that it seems like more now is because we're :> :> :>> paying a lot more attention to it than we used to. :> :> :>>

:> :> :>> And the "mileage" of the orbiters is irrelevant. The problem is :> :> :>> caused by the external tanks, which are new every flight, since :> they :> :> :>> must be expended. :> :> :>>

:> :> :>

:> :> :> What about the tiles? :> :> :>

:> :> : :> :> :What about the *stuff* that keeps coming off and effecting the tiles? :> :> : :> :>

:> :> That 'stuff' is new with every flight. Any tiles that take damage are :> :> replaced with new ones after every flight. :> :>

:> :> So tell us again how 'mileage' on the Shuttle somehow matters... :> : :> :I never mentioned *mileage*. :> : :>

:> So you merely took the side of the guy who did. : :Just like YOU did. :

Well, no. You don't read very well, do you?

: :> Same difference... : :Duh. :

Brightest thing you've said so far...

[Fred J. McCall]

:> :> :> There's never been an issue due to 'tile wear'. :> :> :>

:> :> : :> :> :Has it been shown that the stuff that causes faults in the exterior, :> like :> :> :the current incident for example, NOT been tiles? :> :> : :> :>

:> :> Of course it has! Jesus, what ignorant rock do you hide under? :> :>

:> :> The 'stuff' isn't tiles. It's foam off the external tank. This has :> :> been known for years. Where have you been? :> : :> :It was a simple yes or no question. :> : :>

:> Simple question from a simple source, I guess... :>

:> : :> :But you decided to get emotional about it. :> : :>

:> Don't be a bigger idiot than you already have shown yourself. I've :> been on Usenet for decades. A bit late to get 'emotional' now. : :Then you should know better, shouldn't you? : :> Just another 'Stupid Usenet Tricks 101' tactic on your part - "When :> you're at a loss, accuse the other guy of emotionalism or losing his :> temper"... : :Is this the part where you call me a dictator in 40's Germany? :

No, this is the part where I point out that you're a waste of electrons with no redeeming content.

[Michael Bulatovich]

URL?

[Fred J. McCall]

Duke of?