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NASA Finds 4-5" Crack in Shuttle Insulation
PresidentKang writes "Spaceflight Now is reporting that a large crack has been found in an external tank foam of Space Shuttle Discovery on the launch pad. According to the article: "Engineers inspecting the shuttle Discovery's external tank following Sunday's launch scrub found a crack in the tank's foam insulation near a bracket holding a 17-inch oxygen feed line in place. Some engineers believe the crack must be repaired but senior managers say a variety of options are on the table, from fly as is to making repairs.""
I know the shuttle is at the end of life, but the follow on will still need insulated tanks. The early Atlas had no insulation and needed to be fueled in the final minutes of the countdown. Clearly a problem. But any means of making the insulation crack free, thus flexable, and still able to withstand the launch, thus stiff, would require significent added mass. Mayby an outer shell of carbon composite.
Fix it later? Aren't they running out of time before the July 4th launch? Wrap it in duct tape... that seems to work well for other insulated pipes installed at public institutions (at least from my observations).
On my way to work today I was reading Edward Tufte's The Cognitive Style of PowerPoint, in which he presents an interesting breakdown of the communication structure at NASA. Basically, it seems that many of the technical reports within NASA are now being given as PowerPoint presentations, with formal write-ups being supplanted by lists of bullet points. Needless to say, this means that very important technical information is being distilled to easily-consumable fragments that don't contain much information. The furthur up the chain you go, the more filtered it gets. Is it any wonder why there are so many problems there?
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On the one hand, shuttles flew forever shedding foam and it only became a real problem when a large enough piece tore off to actually damage the shuttle in flight significantly. Engineers accepted the risks with many reservations, because damage was never really that severe. Of course hindsight is 20-20 and this problem could have been rectified if the foam was located interior to the tank as opposed to externally. I think they were worried that if they tried that, there would be voids in the insulation that would allow heat to enter and cause problems, but that was a manufacturing issue which probably could have been resolved with a little ingenuity.
On the other hand, a 4-5 inch crack is nothing to sneeze at and with the aerodynamic forces that batter a shuttle on its way into LEO, any number of things could cause that crack to widen and eventually spilt, teraing off a really large section of foam. It has to be repaired; I don't see how NASA management can ignore this. If they do, and the shuttle is damaged or heaven forbid, destroyed, that's the end of the space program. And probably rightly so. Like to many things, NASA was created due to Cold War concerns, namely that the Russians were going to grab the "high ground" of space and show us up in technical endeavors, weakening our position on the world stage. Like other Cold War relics, it too either needs to change or be dismantled.
I'm a NASA booster (forgive the pun) -- my dream from childhood was to walk on the Moon. But I can say that I find it hard to trust the NASA I see now; it has become hamstrung by indecision, beaureaucracy, and lack of imaginative leadership (with apologies to Dan Goldin, Sean O'Keffe, and Mike Griffin). I wanted John Young to become NASA Administrator -- tough talking, smart, no-nonsense, and imaginative. He might have (and still could if he wanted the job) lit a fire under NASA and got them thinking straight. The problem is, NASA was not prepared for life after Apollo and it shows. The STS was a compromise (no engineer in the early 70's thought solid rocket boosters were a good idea) and a poor one at that.
I think a) NASA needs to be saved from itself and b) the American people have to learn what a truly great resource they have in their space program. Barring either of those, it will be up to private industry to carry the torch.
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Well they've fueled the Shuttle twice already, Tuesday will be the third. Thermal stress was indicted as a contributing factor in foam detaching. Everything probably would have been fine if they had launched the first time, I suspect their cloud distance tolerances are too tight these days compared to thermal stress from fuel cycling on the parts for later lift off.
I'm not saying NASA should have launched the first time, but with only a 30% chance of launch due to weather, why did they even fuel the bird up? Weather should have a least an 80% chance window I would think think to decrease the likelihood of one fueled up scrub after another leading to excessive thermal stress on tank components.
Also while many may see July 4th as a feel-good day to launch (National pride and all that) if anything goes wrong there are religious types both Christian and Muslim that will see it as a sign validating whatever their view of the world is.
Letter To Iran
I've always felt that the shuttle crew (the astronauts that are about to go up in the thing) should have at least 50% say in go/no-go decisions based on findings like this. If engineers find a 5" crack, it's the crew that suffer the consequences of a bad go/no-go decision. One assumes the crew are already part of the data-gathering process. If the shuttle crew say "Low risk - okay to fix on the pad and launch", then that should carry a lot of weight in the final decision. If they instead say "Too risky - I'd rather not bet my life on this particular problem" then that should carry just as much weight.
Of course, NASA may already have such a decision structure in place. But this is Slashdot .. I can posit without the facts very easily here. :-)
When I was studying at Fermilab, Osheroff [link to:http://en.wikipedia.org/wiki/Douglas_D._Osherof f] gave a lecture about the Space Shuttle Columbia. He was selected to head up the review panel, and I'm pretty sure that I remember hearing that the foam was almost certainly the cause of the explosion.
Seems like an unwise decision to let it run without repairing it even if it is unlikely that anything will happen, no?
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Wellll....
..but that isn't the connection he was going for I think. The connection would be God giving the Americans a bloody nose on the day that is their nation's pride day. The significance of it wouldn't be the religious properties of the day, but the secular one.
7 is heavenly perfection, and July is the 7th month.
4 is earthly perfection, and it's the 4th day.
Exactly so. Mercury, Gemini, and Apollo were no exceptions. They were essentially ballistic missile development programs with a very thin layer of space exploration paint applied over them. The moon landing itself was a demonstration of aeronautics and missile technology, and the political message was crystal clear: "We can specify a small target a bajillion miles away, and hit it with a missile." The implication being, of course, that hitting a city-sized target that's only a few thousand miles away would present no difficulties whatsoever.
The shuttle was part of Reagan's gambit to goad the Soviets into bankrupting themselves trying to keep up with our military spending in the 80s. That's why high-tech and expensive was chosen over cheap and reliable. Essentially, it was a weapon for economic warfare. Problem is, the war it was designed to fight has been over for a couple of decades, so we should have went back to cheap and reliable a long time ago.
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I remember some anecdote about Gandhi. Someone asked him how come his stance on something is now the exact opposite of what it was last week. Gandhi said something like, "because this week I know better."
Now I'm no Gandhi, but I can think of a lot of situations when learning something new made me reverse my stance on something. In fact, I consider it to be what every sane human does all the time. Only zealots have one absolute truth and stick to it for ever, no matter what. A scientist (either theoretical or engineer) should have no such things by definition. If you learn some new fact, or do another calculation, or run another simulation, or whatever, and it contradicts what you previously believed, yes, as an engineer I'd _expect_ you to be ready and willing to change your mind about it. Maybe you'll run some extra tests, do more calculations or whatever first, that's ok, but you shouldn't ever have the last week's stance as something set in stone and unchangeable for any reason.
So, well, I won't argue a your point B for lack of enough data, but point A leaves me scratching my head in disbelief. So someone decided that those engineers aren't trustworthy... because they changed their mind? Seems like a pretty weird attitude. I definitely expected that at NASA even management would be a bit more open-minded than that. They're pretty much one continuous experiment and using experimental equipment, so it's exactly the kind of thing that should be _expected_.
We're not talking stuff like designing a bike, where you can just do it all by the book and know the same today as you knew last week. We're talking crazy experimental stuff that noone else has done before, and a lot of it is tried for the first time. Someone calculated that this valve should be perfectly safe, or that foam can't break this time, but essentially it's the first time anyone actually put that valve or that new foam on a rocket and blast it into space. There's a lot of stuff that could act differently than in the simulation, or than in whatever lab tests were done.
So, yes, stuff like someone doing some new calculations and deciding, "teh oops, this thing is gonna blow up" are the kind of thing I'd _expect_.
A polar bear is a cartesian bear after a coordinate transform.
The problem with religious fanatics (and anyone who takes Revelations seriously is a fanatic), is that they will use any evidence as a validation of their delusions. It would be pointless to worry about such people.
Just last night there was a program broadcast on DayStar (a christian tv station) in which a preacher and his obviously strung-out-on-drugs assistant were showing clippings from newspapers, then reading passages from the bible, and crying with joy as they showed this proof that "the rapture" is near.
And yes, I watch that station because it makes me laugh more than comedy central. Good stuff.
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Err, the astronauts get a 100% say whether they go up or not. Think about it, if you thought your life was in serious unacceptable risk getting onto the shuttle and launching, all you have to do is not get onto the shuttle! They're not gonna be chained to the cockpit while NASA go "stop being a bunch of sissies".
If I'm wrong here please someone correct me - but I don't think anybody's ever been forced into going into space against their will.
The revolution will not be televised... but it will have a page on Wikipedia
That issue is addressed in the essay as well (the link above is only a 3 or 4 page excerpt from the 30 page essay). Tufte makes mention of how many students are being taught to prepare a 7 or 8 slide presentation on a topic. Of those slides, there are maybe 10 words or so on each of them. Total time to sit down and silently read through the slides: under 30 seconds. Total time that the student spent preparing the presentation: 1 week.
This guy's the limit!
Space Oddity
David Bowie
Words and music by David Bowie
Ground Control to Major Tom
Ground Control to Major Tom
Take your protein pills and put your helmet on
Ground Control to Major Tom
Commencing countdown, engines on
Check ignition and may God's love be with you
(spoken)
Ten, Nine, Eight, Seven, Six, Five, Four, Three, Two, One, Liftoff
This is Ground Control to Major Tom
You've really made the grade
And the papers want to know whose shirts you wear
Now it's time to leave the capsule if you dare
"This is Major Tom to Ground Control
I'm stepping through the door
And I'm floating in a most peculiar way
And the stars look very different today
For here
Am I sitting in a tin can
Far above the world
Planet Earth is blue
And there's nothing I can do
Though I'm past one hundred thousand miles
I'm feeling very still
And I think my spaceship knows which way to go
Tell my wife I love her very much she knows"
Ground Control to Major Tom
Your circuit's dead, there's something wrong
Can you hear me, Major Tom?
Can you hear me, Major Tom?
Can you hear me, Major Tom?
Can you....
"Here am I floating round my tin can
Far above the Moon
Planet Earth is blue
And there's nothing I can do."
Tsukasa: All I really want, is to be left alone...