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Shuttle Atlantis Launched Without Incident
forkazoo writes "Space.com is reporting the successful launch of the space shuttle Atlantis. There were no major incidents or problems during the launch, except that there was some concern about the weather at the two European abort landing sites. The weather cleared up and the launch was pretty much perfect. 'Preliminary analysis of images taken by onboard cameras revealed expected "popcorning" foam loss during ascent but none that appeared to strike the orbiter. NASA has kept a close watch on the shedding of fuel tank foam insulation during shuttle launches since the 2003 Columbia accident, which claimed the lives of seven astronauts, and made modifications to reduce the amount of debris shed during liftoffs.' The launch was broadcast live NASA TV stream."
"He who can destroy a thing, controls a thing." --Paul Atreides, Dune
I've been watching NASA TV's feed of the mission for the last 15 minutes or so. It offers a real insight into what goes into making a shuttle flight.
Definitely worth checking out.
It is sad that a Shuttle launching with no problems is major news.
Is it only me wondering why the foam thing wasn't a problem in the 80s and 90s, and then after it came up as an issue, the people who pulled off some fantastic stuff with the Mars rovers are surprised when they don't have a problem with the foam, and everything is so tenuous?
NASA TV was just showing some minor thermal blanket damage...
It was a perfect viewing night in northern Minesota .I saw the shuttle pass directly overhead followed by the station 45 minutes later.It was on its second orbit.
I am going to guess that it has always been an issue, but a minor one. Say each liftoff there is a 1% chance of the foam causing a problem. After a few dozen flights of safely ignoring it... BOOM. Now that exact same 1% seems too high, so they try to reduce the danger.
and along with it were other entertaining geek oriented articles such as:
.023% longer than equivalent Nokia N95 battery"
"iPhone battery will last
"Vista successfully installed printer driver"
"Scientists in Norway discover that the sun rises each and every Tuesday."
"iPhone cures herpes."
"$company is forming a patent pact with Microsoft"
"iPhone violates 221 Microsoft patents"
"In Soviet Russia iPhone orders Calamari FOR you"
"1337 H4XZ0R creates a beowulf cluster of iPhones running Ubuntu using his Wii Wifi"
Slow news night.
load "$",8,1
- already
been flight-tested! The first few launches had a external tank. Later launches discarded the paint coating to save a couple tons of payload weight. Reinstating this coating would have the effect of providing a tougher skin to the foam, making it more damage-resistant. Aren't the lives of the crew worth the small hit on payload capacity?Don't worry. They're fixing the whole foam issue in the next space craft by simply redoing the whole design to go back to the Saturn V rocket of the late 60's/early 70's. I think the plans for the rocket coming after the new crew exploration vehicle involve some fireworks strapped to a chair.
Why is is P modded offtopic? A suttle launch IS the topic at hand, and P is commenting on it.
The foam was technically always a risk, but it became a significantly greater one once it was determined that the old foam was environmentally unfriendly (damaged the ozone layer I think), and then it was replaced with a more "green" version that chipped apart much more readily.
Maxim: People cannot follow directions.
Increases in truth directly with the length of time spent explaining them
The problems all started when they changed the foam formula. The old foam (BX 250) didn't break off. However, it contained CFC 11 so was deemed bad for the environment by the EPA. NASA applied for an exemption, but was denied. In 1996, NASA switched to an HCFC 141b based foam. The new foam isn't as good an insulator, so it has to be thicker, and it isn't as strong. This means it tends to break off, and in large pieces. /Waiting for NASA to be forced to use lead free solder. And the fireworks that would cause.
Best I can think of at the moment is that you don't want foam breaking off in the fuel and clogging fuel lines.
Government's idea of a balanced budget: take money from the right pocket to balance...oh who am I kidding?
that is like duct taping your coffee drink on top of the car because it would be "safer" than just leaving it out there- to continue the analogy [a bad one I know] wouldn't it make sense to just take the cup inside the car instead of duct taping it to the roof?
Sigs are too short to say anything truly profound so read the above post instead.
...wouldn't it be safer/smarter to have it INSIDE the tank its self? The problem is, I think, simply a decrease in volume for fuel. The tank has two separate sub-tanks ( H2 plus LOX, plus a third section for control stuff ). Each one would have to be lined. They would probably want to line the third compartment too to prevent stresses from unequal thermal expansion.Then there is also the problem of foam acting chemically with the fuel or oxidizer. It now needs a liner. That is a lot of volume, and now the shuttle does not have enough room for fuel and oxidizer.
Anyway, that's my best guess.
ah but that can easily be solved by encasing the fuel outlet with a mesh of some sort- lets fuel past but not chunks of foam. besides, is it really that much better to have chunks fall off on the outside and shatter the heat shield? I imagine that if chunks somehow clogged the fuel line they would just eject the tank, use the shuttles remaining thrusters to keep a stable trajectory and glide back to Earth.
Sigs are too short to say anything truly profound so read the above post instead.
that foam is a few inches thick, the tank its self is several feet thick, this isnt much fuel and to correct for this you would need to expand the tank a very small amount [6 inches?] to have the same fuel/weight ratio. as for the thermal expansion, the foam on the outside probably already has a similar problem but if it is really a bother, make the foam in an interlocking pattern with a tiny gap or something inbetween each brick, the interlocking layers can still freely expand and yet keep the fuel insulated. lastly, at these temperatures [-200 celcius or so] I dont think there is much in the way of chemical reactions goiing on here- I mean even the reaction of Potassium metal and ice wont happen at these temperatures- so if it did react I would be amazed.
Sigs are too short to say anything truly profound so read the above post instead.
You're insulating the hydrogen at -250C (~22K); the Lox is almost irrelevant, since it has such a higher heat of vaporization and density, and therefore low boiloff. Hydrogen insulation can be and has been done both inside and outside the tank -- the Saturn V upper stages put it inside. Inside the tank, the attachment between insulation and tank material is kept warm, which makes that problem easier. However, it's hard to make a lightweight insulation that the hydrogen doesn't soak through, and hydrogen has a very high thermal conductivity, so that destroys the insulating properties. The foam doesn't have to take pressure, but it has to be sufficiently sealed that you don't get conductive flow past eg your interlocking bricks.
Insulating hydrogen tanks is a decidedly non-trivial task, especially when you want ultra light weight for a rocket. It's rather far from obvious what the best answer is.
IMHO, the solution to the problem is very simple -- don't use hydrogen! Kerosene, propane, and methane are all better alternatives. They actually have higher performance by many relevant metrics, too. Hydrogen is *so* light weight (0.07 g/cc) that the tanks get big. The lower Isp of hydrocarbon fuels is more than compensated for by the better fuel / tank mass ratio in the vast majority of applications. And that's even before you count the high cost of handling hydrogen and designing engines to work with it -- it's enough colder than LOX to make a difference, and it has myriad other handling concerns that make the development programs expensive.
And yes, I do build rockets for a living. No, I haven't ever worked with hydrogen, but there's a reason for that...
"Insulating hydrogen tanks is a decidedly non-trivial task, especially when you want ultra light weight for a rocket. It's rather far from obvious what the best answer is."
Aerogel. Ultra-light weight, best thermal insulator known to mankind (other than a vacuum, which is another possibility). Nobody makes it in sufficient volume though, but that could change if NASA got behind it.
"Victory means exit strategy, and it's important for the President to explain to us what the exit strategy is." G.W.Bush
If all three SSMEs fail in the first 90 seconds, the aerodynamic drag of the orbiter might tear it away from the tank, where it would disintegrate from the high angle of attack and the backwash from the SRBs. You really don't want to interfere with the fuel flow. And that flow can drain a swimming pool in 25 seconds, so it can probably suck bits of foam through a mesh. Cryogenic tank design is one of those areas where it's pretty unlikely that people like us will have good ideas that the rocket scientists haven't already excluded.
Not true on all counts. Aspen Aerogels makes a felted insulating blanket out of the stuff; I've worked with it for Lox insulation. It's not even all that pricey -- $4/sq ft, 1/4" thickness. It works *great* on the ouside of the tank, when it doesn't have to have any strength (I wouldn't want to expose it to any sort of aerodynamic loading, though). However, it's quite porous (aerogels are inherently open-cell structure) and soaks up liquids quite well. I've personally experimented with immersing it in LN2; it's obviously not the right choice on the inside of the tank.
Oh, and vacuum isn't a possibility -- the structure required to hold vacuum is *far* heavier than that required to hold pressure. Vacuum is the insulator in standard cryo shipment (dewars), but there weight isn't a concern.
i being in my 20's in my life time space shuttles blow up or launch without incident, in my parents lifetime nasa landed on the moon why do we not care/assume the worst that is what we have experienced
IT was an issue. Discover was seriously damaged in 98 or 99 and heated gasses seeped into the shuttle itself and burned alot of components and damaged the wing.
http://saveie6.com/
If the turbines ingested much of anything at all, they would fail. And turbines don't fail gently. They fail by throwing bits of metal outward that were formerly rotating at 30-100,000 rpm. The Shuttle can survive an engine shutting down (and has), but likely not one exploding.
There are glide-back abort modes, but they're very risky, and it's not clear things would survive turbine failures long enough to enact them.
All that said, I don't think chunks of foam coming off inside the tank is normally considered a huge concern. (But I don't really know; I've never worked with hydrogen.) See my other comments for why it's not obvious where to put the insulation; there are many factors at work. That's what makes rocket science hard -- none of the individual bits is *that* hard, there's just thousands of non-trivial details to work out, and they have this habit of interacting with each other.
1. Materials. The alloys used to make the tank are designed for cryogenic service. they will not exhibit metal fatigue or stresses. They are also designed not to react with they hydrogen or the oxygen. many materials start acting funny (funny boom, not funny haha) when exposed to pure environments of either propellant. thermal cycling on an ET is very limited anyway, perhaps a handful of tankings ahead of a launch depending on the number of scrubs, so the shrinking and reexpansion of the tank when cryo temperatures are applied or removed does not occur enough to cause metal fatigue. they have people keeping track of such things.
2. Manufacturing complexity. Most of the ET foam is applied with a robotic sprayer once the tank is completely built. Retooling the assembly line to spray the inside of the tank would be an expensive proposition in and of itself, not to mention requiring the tanks to not be completely assembled when the foam is applied. the tank seams would thus not be as well insulated, causing ice to form. The spray on insulation isn't what killed Columbia anyway. the robotic process allows the foam to be sprayed uniformly with few voids in the foam. the CAIB concluded that hand applied foam applied to reduce aerodynamic loading at the orbiter attach points as well as prevent orbiter killing ice formation at those same points is what brought down Columbia. the hand applied foam cannot be applied with nearly the same uniformity as the spray on foam. The tanks were redesigned to eliminate most of the need for hand applied foam. This doesn't prevent mission managers from being paranoid about anything coming off the tank and causing a problem.
3. Foreign object debris. the popcorning seen on liftoff is due to aerodynamic stress and vibration that the vehicle experiences during the climb. there is no reason to believe this won't happen if the foam is inside the tank. (an additional cause of foam shedding in this case is mentioned in 1 above)
The turbopumps on a shuttle engine are very powerful and built to tight tolerances. Even a very small piece of debris entering these pumps can tear an engine apart when it is operating at full capacity. Filters are placed in the fuel lines ahead of the pumps to help prevent such things from happening, but they're meant to catch the odd piece or two. You can see from the launch video how much popcorning can occur during a flight, so placing the foam inside the tank where it can access the fuel line creates one of two scenarios. 1. the filter clogs, starving the engine of fuel, shutting it down and creating at best an abort scenario, which, depending on the point of the climb at which it happens increases the risk to the crew and at best forcing NASA to spend extra money from its dwindling budget to retrieve the shuttle from Africa. 2. the filter fails, allowing FOD into the engine, blowing the back end of the orbiter off and creating a very bad day for everybody.
In order to prevent this FOD, a liner, perhaps made of a metal alloy would be needed. This 1. increases manufacturing complexity even more. 2. to borrow your argument, increases risk due to metal fatigue and stresses. and 3. adds a gigantic amount of mass to the vehicle, reducing the payload capacity. when you're getting to orbit, payload is king. the more payload you can get to orbit the better. the success of many programs, manned or otherwise, can hinge on tens of pounds in the mass budget either way. that's the nature of the game. the first few flights of the shuttle, the tank was painted white. This created a nice, pretty, uniformly white vehicle. Then someone pointed out that the paint served no engineering purpose and was costing 500 pounds. The paint requirement was then deleted and 500 pounds more payload could be sent to orbit.
I can probably think of more engineering arguments, but it's late and Iv'e had to retype this once already.
> The problem is, I think, simply a decrease in volume for fuel.
[...]
> Then there is also the problem of foam acting chemically with the fuel or oxidizer.
[...]
> Anyway, that's my best guess.
Good guesses. Reality is stranger.
The tank is made of aluminum alloy. Very thin metal. At supersonic speeds, the tank would heat up. The increased temperature would cause the walls to become weaker, and the tank would buckle and rupture. By putting the insulation on the outside, they keep the metal of the tank walls super-cooled. Neat idea. The Delta rockets do the same thing.
Another reason is that if you think foam falling off the outside of the tank is bad, just imagine what foam falling off the inside would do. yup, it would get sucked through the engines. The turbopumps which inject fuel into the main engines are high-energy bombs, just waiting for an excuse to fly apart. So rockets (like Atlas and Saturn) with internal insulation require filters on the fuel lines to make sure they don't ingest any foam.
Hey the paris hilton story was entertaining, she completely cracked. I love it.
But I agree with you without incident? Wow! so you mean everything worked... like It has 90 percent of the time with the shuttle? Like why they test and rest the shuttle before launch?
Tell me when another one blows or we find aliens, sadly space has once again become boring. I'm sorry to say it but until I'm going up, I really could care less, the rate we are going (people afraid to fund it) we'll not even land on mars in my life time. I'm only 25! Even the stephen hawking and lord british space flight was only mildly entertaining (lucky bastards).
But this is hardly the worst article. The political section has very little "news for nerds" it's been turned into biased propeganda like many other websites. Your rights online is more about small corporations business rather then people. We have "fuck microsoft" over 90 percent of the site. Fuck Sony on games. Books mostly talk about books that are passing. And the rest? Either the news of the day (which you can read on any other site) or agenda pushing. A little benign good news isn't a bad thing in that case.
It's not a bad thing, but slashdot has turned from a very niche site into a propeganda site. But even there it's still a little less biased than most others. Though any fight about global warming or politics has the same ways to get karma (attack bush, go pro global warming). So it gets tired after a while.
People would think and a grab dream and wish.
Sometimes it worked.
Dream and take.
"Fear is the rootkit of democracy.." Blarkon
That said, it's neat stuff. We've been experimenting with it where I work. A colleague of mine had some left over from some work he was doing and replaced the foam in his coffee travel mug with it. He now doesn't have to worry about his coffee getting cold for a Very. Long. Time.... (Hmmmm....ThinkGeek licensing opportunity perhaps? ;) )
for the browncoats among us, this flight also marks the maiden voyage of Firefly into the black, courtesy Mission Specialist Steve Swanson. Hopefully the mission planners on the ground are scheduling a full day off while the DVDs get watched.... :)
If you haven't tried it, you should check out the Aspen Aerogels stuff. It's *far* easier to work with than the blocks (though somewhat heavier), and surprisingly cheap. Even with the improved strength, and the fact that the Shuttle "only" sees about 500 knots indicated airspeed, I'd be reluctant to trust it on the outside. Let alone the environmental protection from humidity and such. Now, if we could just *stop* *using* *hydrogen*, this would all get so much simpler and cheaper...
The foam problem started when the EPA banned freon. NASA used freon based foam as insulation prior to 1997. Freon based foam doesn't cause as much damage to tiles as non-freon based. Search Google for shuttle freon foam for plenty of references.
the paint might prevent the popcorning, which is no threat to the shuttle anyway since the pieces are too small and usually occur after the majority of the atmosphere has been exited. However, no amount of paint would have prevented the large chunks from falling off during STS 107 or 114. The forces from the air escaping the voids in the hand laid foam is too great, which is why removing most of the hand laid foam whenever possible has already been done.
"Shuttle Atlantis launched without incident" ... I mean its nice and all .. but did we have to emphasize the "without incident" part of it - should it be news worthy that it launched without incident? Are we getting that cynical? :(
_Vishal www.squad9.com
If the coated surface helped reduce the occurrence of FoD then maybe those 500 pounds were well spent. And then maybe they could work on ways to reduce the weight, while keeping the coating.
True. For cryogenic production, perlite is used but for bulk LH2 storage it's an inner SS (I forget which grade) vessel surrounded by a carbon steel shell. In between the two is reflective material and vacuum. Aerogel is interesting but I don't work in cryo anymore, so I can't really comment about that.
Neat cryo trivia: cold liquids will condense water vapour out of the air, but an exposed pipe that conveys liquid hydrogen will *liquefy the surrounding air*, leaving a mixed pool of liquid nitrogen and oxygen on the ground.
Aerogel is far better than conventional foams, including high performance CFC-filled foams. It is far worse than a good vacuum dewar, though.
The extra fun part about the LH2 plumbing is that the condensing liquid is oxygen-enriched, which makes it even more hazardous. As if the 4%-75% explosive range in air wasn't wide enough...
And people wonder why working with LH2 is hard ;)
Yeah, no asphalt near LOX, eh? Facilities I've seen had SS angle iron suspended underneath the piping so as to drain the condensed air to a "safe" location. Sparking clothing is also a no-no.
Post-launch in-orbit inspection has revealed a potential problem. There is a small four-inch tear or bunching of a thermal blanket on the OMS pod near the tail. It's not clear at this time if this will be an issue on re-entry. This area of the orbiter receives less heating on re-entry, but thermal protection is still important. NASA will probably release more details later today.
Article: http://www.nasaspaceflight.com/content/?cid=5127
Image: http://www.cfnews13.com/uploadedImages/Media/Video /0037(4).jpg
The Mars Rover program was a smaller team, off to the side. It is a project which hadn't drawn the attention of the bureaucracy, so it wasn't loaded down the way the big 'meat and potatoes' projects are. Unencumbered, it was shockingly successful. Not unlike the way 'skunkworks' projects work every day in the real world.
With the carbon footprint each shuttle launch represents, it's a wonder NASA is allowed to launch any of these 80's-style dinosars.
Of course, "I for one accept that in Soviet Russian Beowulf Clusters mod inconsiderate clods down!" would have been accepted...
"He who can destroy a thing, controls a thing." --Paul Atreides, Dune
It was a problem in the 80's and 80's - but it never caused significant damage, so NASA largely ignored it. Just as with Challenger and the O-rings.
The media has an irrational, entertainment based, algorithm at work when it comes to selection and promotion of news stories. Promotion of space flight stories is generally good, however it's clear judging from the number of comments posted here that it doesn't mean much to the slashdot crowd who correctly filter as not much in the way of new or interesting. The gee whiz factor works for CNN though.
According to this article:
http://www.capmag.com/article.asp?ID=4448
The foam that broke off was from the old foam....but it was stock piled BX 250. This foam weakens with age.
Gorkman
Carbon footprint? Are you trying to be funny? The shuttle burns liquid oxygen and liquid hydrogen. The resulting exhaust is not carbon dioxide, it's water vapor. Get a life.
Maxim: People cannot follow directions.
Increases in truth directly with the length of time spent explaining them
Turns out that there's a problem anyway.
u ttle.ap/index.html
http://www.cnn.com/2007/TECH/space/06/09/space.sh
Now, THAT is sad. And I hope that it really is 'no big deal'.. Even though my first reaction was "Oh S*&t".
May the crew have a safe return.
Huh?
http://www.pbase.com/rking401/shuttle_launch_june_ 8_2007
These were taken from 9 miles away
The problem is the "shuttle consept of doom", not the foam... Something has to cover that rocket, foam is better than ice. If the shuttle didnt "ride" a rocket then there would be no need for foam, inside or outside...
And we're back to a 'simple' stage rocket....