NASA Decides No Fix Needed for Endeavor's Tiles

bhmit1 writes "It looks like NASA is reporting that no repairs are needed for Endeavor. 'After meeting for five hours, mission managers opted Thursday night against any risky spacewalk repairs, after receiving the results of one final thermal test. The massive amount of data indicated Endeavor would suffer no serious structural damage during next week's re-entry. Their worry was not that Endeavor might be destroyed and its seven astronauts killed in a replay of the Columbia disaster — the gouge is too small to be catastrophic. They were concerned that the heat of re-entry could weaken the shuttle's aluminum frame at the damaged spot and result in lengthy post-flight repairs.'"

Comments

I'm glad I don't have to make these calls

[ExE122]

Their worry was not that Endeavor might be destroyed and its seven astronauts killed in a replay of the Columbia disaster -- the gouge is too small to be catastrophic. They were concerned that the heat of re-entry could weaken the shuttle's aluminum frame at the damaged spot and result in lengthy post-flight repairs

And I'm sure thats the only thing the astronauts were worried about as well... the precious shuttle.

It reminds me of a while back when a friend of mine called his mother to tell her he had a few drinks and was gonna stay the night at a friend's house. Her response was, "Yeah, I wouldn't want anything to happen to the car."

Regardless, I admire their fortitude given the history of the Columbia and all that has happened. I hope everything goes well and they get home safely.

--
Captialism: When it uses the carrot, it's called democracy. When it uses the stick, it's called facism.

Re:I'm glad I don't have to make these calls

[ExE122]

NASA haven't panicked and issued all kinds of worrying proclamations when it wasn't worried in the past: why start now?

Because they weren't all that worried about Columbia either. Seven astronauts died because of that.

Don't get me wrong, I see what you're saying. The damage may indeed be comparable to previous missions that went off without a hitch. And it is true, all of the lab tests show no cause for concern. But as another poster mentioned below, all the lab tests in the world can't make up for a real world scenario. The real world always has another trick up it's sleeve.

And you also need to realize that NASA needs to be extra cautious. A repeat of the Columbia disaster would raise some serious concerns about their credibility and may be detrimental to the future of space exploration in general.

--
Capitalism: When it uses the carrot, it's called democracy. When it uses the stick, it's called facism.

Re:I'm glad I don't have to make these calls

[Vellmont]

And I'm sure thats the only thing the astronauts were worried about as well... the precious shuttle.
If the only thing mission control was worried about was "the precious shuttle", then they would have just sent them out right away to fix the gouge.

Spacewalks are potentially dangerous. Micro-meteorites could tear right through a spacesuit and instantly kill an astronaut. They aren't taken lightly and are always judged whether the benefits justify the risks. In this case, they didn't.

Re:I'm glad I don't have to make these calls

[Ellis D. Tripp]

>>Because they weren't all that worried about Columbia either. Seven astronauts died because of that.

In all fairness, nobody at NASA knew the extent of the damage to Columbia prior to reentry. There were engineers who suspected that there might be some, and wanted photography to be sure, which NASA disallowed. If the existence of a large hole in the leading edge of the wing was known, some type of rescue operation could possibly have been put into place, as there was no repair possibility at that time.

In this case, NASA had detailed imagery of the damaged area several days before the return. That allowed for detailed analysis and laboratory testing, which have apparently convinced NASA that the extent of damage is limited enough that no repairs are required prior to reentry.

I would like to know what assumptions were used in making the "no repair" decision, nonetheless. It would seem to me that even if the damage was not severe enough to REQUIRE the repair, this situation provided a chance to test out the newly developed repair techniques and materials in a "real world" setting, allowing engineers and future crews to gain more confidence in the repairs if and when they are required on a future mission. Is the risk of an EVA/repair causing further damage really high enough to justify throwing away what could be a very valuable "learning experience"?

Re:I'm glad I don't have to make these calls

[couchslug]

"And you also need to realize that NASA needs to be extra cautious. A repeat of the Columbia disaster would raise some serious concerns about their credibility and may be detrimental to the future of space exploration in general."

They don't care enough about space exploration to halt the use of old systems like the Shuttle, continue exploration with unmanned systems, then send meat into space with more mature technology.
This isn't 1492, and we are under no pressure to send crews off in the modern equivalent of a wooden ship. We can learn and observe and manipulate with unmanned systems that have a much more rapid rate of evolution than that of man-constrained systems. If we want humans to see the process we can record it.
If an unmanned system is lost we don't have to deal with the hysteria that the public expectation of zero casualties engenders. (Good thing we didn't expect zero casualties in the era of test pilots, or aviation would not have gotten very far.)

Re:I'm glad I don't have to make these calls

[zippthorne]

It is unlikely that a rescue would have been possible. It would've required extreme fast-tracking of one of the other shuttles, which NASA has proven to be unable to do. While I was living in FL, I think there was maybe one launch that went up at the original scheduled time, many were postponed, and the vast majority ended up postponed to over a week later.

The disappointing thing about Columbia however, is that knowing no rescue or repair would be possible they decided additional imaging was unnecessary: The astronauts' fates were already decided, so why bother getting some pictures? It would have been nice, for the investigation later, to have such images. Even if they had landed safely. It's doubly disappointing because it seems DoD chose not to take images of their own initiative, either. It would've made a good training exercise even if the data itself turned out to ultimately be useless.

At the time, it felt to me that the decision not to take or ask for pictures was akin to the ancient sailor's superstition against learning to swim.

IANAAE

[Stanistani]

Here's where we get to watch a lot of folks decide whether to comment on the effects of something outside of their experience and expertise.

I've seen photos and 3D imaging of the bashed tiles. I know very little of the forces involved. I have seen no structural analysis of the materials that are beneath the deepest part of the gouge.

To a limited extent, I can compare this damage to the past damaged tiles. There seem to have been a number of similar damaged tiles in the past, and those flights landed safely.

The astronauts could slap some of that goop on the gouge, but risk damaging the tiles by accident, or changing the aerodynamics of the craft.

There are many unknowns. I really don't know what will happen when Endeavour reenters.

I wish them well, and hope that NASA can complete the remaining shuttle flights without mishap.

Re:A chance for testing lost

[RoverDaddy]

But most betas don't run the risk of killing 7 people. There are serious risks involved in -doing- the patch too.

To err on the side of caution...

[gihan_ripper]

...why don't they replace the tiles anyway, just to be sure? The article suggests that a spacewalk would create added risk, but we know that spacewalks occur all the time routinely. Perhaps there is a financial motivation for not carrying out the repair? I don't know. What I'd like to see is an actual breakdown of the possible positive and negative consequences of each course of action and the probabilities that NASA has assigned to the outcomes. I'm really hoping that they've put some serious statistical analysis into this decision and aren't just flying by the seat of their pants. Certainly, the article quotes a Nobel Prize-winning physicist, Douglas Osheroff, as saying that the repairs "can only increase their chances of making it down."

Re:To err on the side of caution...

[bev_tech_rob]

It would be problematic to replace the affected tiles.....if I remember from old articles (don't have links, sorry), each tile is unique and not the same size as its neighbor (although they visually appear to be). You would have to grind it or somehow alter the shape to make it fit the hole precisely as it should.

If they used the caulk, I would worry about the goop bubbling out or not being flush with the surrounding surface, thereby creating drag which may pull the whole tile out, which would leave a BIGGER opening with sharp edges causing more tiles to be torn off...I would think the black paint they were discussing wouldn't hurt.....just my .02 cents...

Re:To err on the side of caution...

[RoverDaddy]

I read Osheroff's quote and decided he's talking out his ass (or it's a lousy quote). Perhaps successful repairs can only increase their chances, but things can and do go wrong, and it wasn't explained how Osheroff was in a better position to make the analysis than the people at NASA doing it. BTW, if you read the article carefully, it seems that financial considerations would lean toward doing the repair, not avoiding it. Leaving the gouge in place may result in more down-time and repair work for Endeavour on the ground.

Re:Disaster waiting to happen

[TheMeuge]

Life has a cost too.

We seem to have forgotten that in the U.S. lately. Granted, the integrity of the shuttle frame is not worth human life, but the panicked semi-troll responses to this crisis made me realize yet again how far we've fallen as a society.

The same people are "concerned" now, as the ones who were calling for ending the space program after Columbia.

We are so fat and content that we seem to think that anything that interferes with our blissful lives must be a curse. We have forgotten the drive and determination of scientists, engineers, and many others, which made the world we're living in possible. Make no mistake about it - without self-sacrifice, many of the technological and scientific developments that shaped the latter half of the 20th century would not have been possible.

Yet the population, spurred on by the scaremongering media, seem to think that we've now magically gotten to a point at which we can make everything safe. Well... we almost can... if we all just stay home. But if we want another revolution in the development of our species, like the one that spanned 1850-1975, we will have to accept that some things are worth it. Yes, it's important to minimize risk... but sometimes you have to accept a reasonable amount of risk, take a deep breath, and just go.

Anyway, sorry about the rant...

Re:If I were one of the shuttle astronauts

[Anonymous Coward]

Actually if you were one of the shuttle astronauts, you'd probably have enough confidence in the engineers on the ground to make the call correctly.

You don't make something as complex as a shuttle mission work correctly by second guessing everybody.

Re:Why not change the design?

[ahuard]

The feather reentry technique is only useful at suborbital speeds. How do you expect the spacecraft to slow down to these speeds? The only option is to use the underside of the shuttle as a heat shield as it is barreling through our atmosphere. What other options are there? You can't use a fuel burn because that would enormously increase the launch weight, and therefore the cost, of every mission. The shuttle was designed by some of the best aerospace engineers in the world. I'm sure every crazy reentry option was on the table during the design phase and they chose the one best suited for the job.

~Andrew

Re:same moron with mod points again

[posterlogo]

Your comment is off topic (as is mine, probably). I hope your whole thread gets modded down to obscurity. Stop whining about mod points.

Re:Disaster waiting to happen

[Chris Burke]

Well it's not offensive when you put it like that, but it's still not right. They are still considering the lives the astronauts at the expense of the shuttle. Their analysis and simulation said that with the present damage the worst that will happen is that the shuttle's wing might be damaged and require lengthy, expensive repairs on the ground. That's the money angle. They could try to patch the damage and prevent this, but EVA is dangerous and these repairs are difficult, if it ends up causing more damage to the delicate tiles then all the astronauts' lives are in danger. On-the ground repairs, no matter how expensive, are a better option.