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Shuttles Grounded Once Again
PipianJ writes "After discovering that the piece of the shuttle that fell off mysteriously, not actually striking it, (as reported earlier) was a piece of foam insulation not unlike the piece that ended up in the destruction of Columbia, Yahoo News reports that NASA has once again grounded the shuttle fleet."
Perhaps the shuttle fleet should be grounded permanently? We seem to be so intent on getting back into space that we don't actually fix anything.
NASA needs to re-adopt the paint on the external tank. At least on the shuttle side of the tank, the foam insulation needs a coat of paint to eliminate the porosity of the foam. That will lock the ice out of the foam and prevent it from tearing it off the tank.
The paint probably ought to be non-stick coated to inhibit excess ice formation too. Then put heaters in critical locations to break up the ice while the shuttle stack is sitting on the ground, or still moving at slow speeds. That way, supersonic chunks of ice won't go zinging into the shuttle body and we don't have to wonder if we've launched another one way mission to space.
Behold, this dreamer cometh. Come now, and let us slay him... and we shall see what will become of his dreams.
Except Discovery is not "seriously damaged".
(And another shuttle would hardly be "scrambled".)
And the fact that the over 15,000 pieces of debris that hit the shuttle on the previous 113 flights didn't cause any problems 112 of those 113 times. You might say once is too many, but we're only finding issues here because we're looking so hard.
And, no, it's not "hard to do" with one shuttle on orbit. The fleet is grounded. Discovery is on orbit. Once it returns, no further shuttles will be launched until further notice. Quite simple.
This looks like a simple and fundamental design flaw. Now if they had attached the main tank and boosters to the other side of the shuttle the vulnerable tiles would be out of the way of anything that falls off.
The foam didn't even strike Discovery! It's just that it *fell off* at all, and the fact that everyone is paying attention to it now because of Columbia.
Yes, they'll be coming back. And no, it won't be particularly interesting if they land safely, because the foam didn't even hit the shuttle, not to mention that the shuttle has been hit by debris over 15000 times in the history of the program. Over a hundred tiles alone fall off and need to be replaced on every mission.
There's nothing interesting about this except the media circus. It's to bad they don't pay more attention to the *actual science* that NASA is doing with the shuttle, on this and the hundred-some other missions instead of obsessing over foam.
Let's see here: budget cuts, failing space program, failing economy, global criticism regarding human injustices abroad, rapid decrease of freedom and increase of governmental power...sounds alot like the SOVIET UNION doesn't it?
It takes just a moment and an action to destroy. It takes some time and thought to create.
what do we expect to find? The shuttles are the most complicated pieces of machinery ever built, designed to launch into space with a controlled explosion, and then return to earth.
we expect to find what we did not see before.
we expect to improve the design drastically, so that it is no longer the most complicated pieces of machinery ever built
moore's law works on the shuttle too. if only NASA, and the government goons, would open the development and research funding to the public market.
it is about time hyundai were making launch capsules, or Mercedes at least. let the shuttle only drive that issue forward. please.
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --
Takeoffs are optional. Landings are mandatory.
NASA has lost two vehicles by disregarding safety issues as "overreaction" and proceeding with optional takeoffs.
NASA has now found evidence that the design flaw that brought down the last shuttle is still present. By saying "OK, no more takeoffs until we have a better solution", NASA has done the right thing.
"Better solution" could be as simple as changing the formulation of the foam or sacrificing some payload capacity to lay some paint over the foam. "Better solution" could be as expensive as permanently grounding the Shuttle fleet and diverting the remaining Shuttle budget towards the development of a new launch vehicle.
Which solution is appropriate depends on engineers and politicians. Removing the politicians entirely from that equation is also important - but at least we've seen some evidence today that NASA is learning from its mistakes.
In response to an edict from the EPA, NASA was required to change the design of the thermal insulating foam on the shuttle's external tank. They stopped using Freon, or CFC-11, in order to comply with the 1987 Montreal Protocol, an agreement designed to head off doubtful prognostications of an environmental disaster. This resulted in 10X the level of tile damage since 1997 (when the new foam was implemented) per flight.
I hope this isn't what caused the damage we've seen lately, but if it is, it begs the question, is it worth using CFC-11 for safer shuttle flights given the relatively small number of launches that occur?
Close, but not quite.
The shuttle-as-the-second-stage-of-a-Apollo V was an alternative to the SRBs later in the design.
I liked that idea signifigantly better, because the Saturn V stage would have been useful for other things...
The shuttle was initially supposed to be all-reusable. Two shuttle-vehicles would launch together and one would go all the way to orbit and the other would go back to the ground. They could do it, but not in the budget given with the performance required. They could have made it smaller but fully reusable and in budget, or use a drop tank and make it bigger and stay in budget.
Gentoo Sucks
side mounted payloads on rockets make no sense. Side mounted payloads that include living, breathing people are even stupider. Inline rockets with launch-escape towers don't have to worry about falling foam or other debris hitting brittle cutting-edge materials. Spacecraft should be delibrately robust, not fanciful and unnecessarily dangerous.
So, NASA, you proved the point. If enough money gets thrown at the problem, yes, anything can fly. Even pigs and white elephants.
The count as I understand it: one debris strike knocked off a piece of wheel-well tile, one bird got skewered on the ET during liftoff and the huge chunk of foam narrowly missed the right wing after SRB separation. Any other "anomalies"?
I just hope that Discovery makes it back safely. After she returns, let's put the Orbiters in museums for a well deserved rest. It's been a good run, but these birds are done.
If you've read my other posts here, you know my solution to the "ISS needs Shuttle" line.
Josh
gigantino.tv - Heavy but weighs nothing.
Was there any/much foam shedding prior to the removal of paint from the external tank?
Just wondering what the adhesive effects of all that white paint were.
"and essentially the practical end of the ISS"
And why would that be? It might be the end of NASA and U.S involvement in the ISS. I wouldn't be surprised if the Russians would keep ISS going. They have an inexpensive, ultra reliable pair of spacecraft unlike NASA, and can service it though at modest levels. They wont ferry any more U.S. astronauts there because NASA has been a deadbeat for the duration of the last 2 1/2 years, and hasn't paid Russia to carry U.S. astronauts and supplies to the ISS (because Congress slapped an embargo on Russia over Iran's Russian reactor). The Russian's said no more to the free ride a few months ago.
As you recall the Russian's were forced to abandon Mir as the price for their participation in ISS. The core of the ISS is essentially Russian built Mir-2. Don't imagine they want to let NASA incompetence torpedo their long running permenent presence in space.
I imagine at this point the Russians would dance a jig if the U.S. threw in the towel on ISS so the Russian could take complete ownership of it, and partner with the ESA and countries who aren't so wellll, NASA. Russian's have zero reason to partner with NASA at this point since they get no funding from the U.S. NASA didn't have much to offer the RSA except money and that is no more.
ISS is of marginal real value but the Russians haven't squandered the vast sums on it NASA has so its a better return on investment for them especially with NASA out of the way.
A few weeks ago the Russian government green ligthed development of the next gen Russian manned spacecraft Kliper and ESA is very interested in partnering with them so Europe will have a manned space program free of NASA's poor performance in recent decades. I'm taking bets Kliper flies before CEV does (though Mike Griffin sure is an improvement over O'Keefe').
@de_machina
http://www.spaceflightnow.com/shuttle/sts114/05072 7palrampimages/
looks an awful lot like the unidentified chunk of debris that missed the starboard wing (scroll to bottom of link).
http://www.spaceflightnow.com/shuttle/sts114/05072 6images/
It's true. The SR-71, once in the air, has no fuel. The seals under the tanks can't hold with that massive amount of heat. It's leaking fuel as it takes off. Once in the air and at full burn, the titanium expands and fills in the cracks, but the SR-71 has to be refuled in-flight right after takeoff.
"the shuttles have been hit with debris over 15,000 times, mostly during launch."
You can rationalize it all you want but the fact is its a bad design. A couple basic reasons:
- The foam is applied by hand to the ET, it is a hack added after the design was done to deal with all the ice that they had to know would be there. but chose to TOTALLY ignore in the original design. Applying that foam by hand is an accident waiting to happen, because it ends up different on every tank. If there are air bubbles under it at the wrong place its going to blow off and hit the shuttle. Most of the time its non fatal but it can be fatal anytime. The foma that did fly off was heading in the general diretion of the leading edge though it didn't get close.....this time. Its always a gamble.
- Prior to the Shuttle U.S. spacecraft had all the most delicate and important manned part of the stack, that had to survive the whole mission, and keep the crew alive at the top of the stack. Debris and ice rained down all over Saturn V but there wasn't anything fragile to hit and the stuff on the bottom is ditched early and isn't around for reentry. The crucial heat shield was totally protected since is was between the capsule and the stage below so it couldn't get damaged by debris. All the new designs return to putting the vehicle at the top of the stack because that is a good design. Handing it on the side of a cryo tank was a now fatal mistake.
The shuttle by contrast has a massive, very fragile array of heat shields all of which are out in the open and most of which are right next to the ET which sheds debris and or ice every flight. Its an accident waiting to happen. Its a crap shoot if debris falls off in the right place to strike the wrong place on the shuttle. In Columbia it did. There are odds it will happen again, so now NASA knows it has to spend half of every mission just checking to make sure a debris strike or a faulty tile isn't in the wrong place, and it can't fly any place but the ISS in the event the roll snake eyes again and get damage to the heat shield in the wrong place.
@de_machina
Why not just redesign the tank? The insulation could be placed INSIDE the full tank.
Now where did I place my slashdot password......
It would be if you put a SHUTTLE up there. Don't think anyone is going to be so foolish as to put a massive heavy lift launcher and a crew carrier in to the same vehicle any time soon.
The CEV designs and Kliper are pretty tiny compared to the Shuttle.
It would be totally OK to stap a heavy lift cargo carrier where the SHuttle is because you aren't going to have it reenter the atmosphere in most cases and if you did want to return something big to earth you wouldn't have a crew in it that would die if was damaged.
@de_machina
Park it at the Space Station for use as quarters and an extra instrument platform, then send up a couple of extra Soyuz to bring the crew down??
How about a big Nuh UH! The Russian Soyez can only hold 3 passengers. which is why the space station will never reach the intended capacity of 7. No one build the proper escape pod. Soyez takes 3, station has 2, shuttle has 7. Hmm. it's going to be a tight squeeze, or someone will be left behind.
Or why not reinforce the bottom and leading wings of the orbiter with some material strong enough to deflect any foam strikes, but can burn off harmlessly on re-entry, exposing the thermal tiles under?
What's "funny" is that the shuttle wasn't supposed to be the be-all end-all solution, they only made five of 'em for pete's sake. With a "production run" of five, the only label that could reasonably be applied is, "prototype"
The space shuttle experiment was a great success. It proved that with late 70's technology, an RLV was simply not as cost effective or as safe as you would expect. Of course, saturn V's are not much better ($ per launch), but they make up for it in $ per kg.
Can you be Even More Awesome?!
IF we're talking of a saturn V, I don't think the shuttle would take the full stack to be workible, it would be more reasonible to me to delete the S-IVB third stage, and replace with a shuttle. With some modification to the shuttle, such as deletion of the main engines to save weight, i bet it would be awfully close to the mass of a loaded S-IVb.
Anyone have the raw numbers on this?
In either case, asymmetrical loading is as much of a dumbass idea as a topheavy model.
How about this idea: Redesign of the engines to accept hypergolic fuels, and trade ice and foam for dangerous chemicals, which the shuttle already has on board, admitedly in lower quanities.
I know that they used to paint the ET, and why they stopped. But is there any evidence at all that paint kept the foam, or would keep the foam from peeling? Any data at all?
Touch everywhere, even when inappropriate.
I don't think that you are going to get a truly reusuable vehicle in the traditional rocket shape, I'm afraid. Saturn worked because it was designed to be thrown away, except for the reentry vehicle. If we had continued along that path, then this is a perfectly sensible approach to the problem. With a reusable vehicle, you are going to have exposed heat shields at launch, it is pretty much unavoidable.
You can only drink 30 or 40 glasses of beer a day, no matter how rich you are.
-- Colonel Adolphus Busch
The weight of the shuttle (with full cargo) is more than saturn 5 could lift into orbit.
http://en.wikipedia.org/wiki/Saturn_V
http://en.wikipedia.org/wiki/Space_shuttle
So lifing all that reusable structure is what makes it more expensive per kg.
"The weirdest thing about a mind, is that every answer that you find, is the basis of a brand new cliche" -