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New Shuttle Fuel Tanks Ready
confusion writes "NASA has completed the redesigned fuel tanks for the Shuttle scheduled to for launch in May or June of this year.
"On the new tank, NASA has reconfigured the struts and fittings where foam was prone to peeling off, and installed heaters to prevent ice from forming. The new tank has cameras that will allow ground workers to monitor for damage as the shuttle ascends.""
So when are they going to redesign the shuttle though?
The main problem on the antiquated space shuttles is the heat-resistant tiles. They're extremely expensive, and not very good. They're so soft you could problably crush a piece with your hands, which means they're easily damaged during flight (and we've seen the fatal results of that).
Troy Hurtubise, the Canadian who did the famous bear-proof suit documented in the movie Project grizzly, spent 18 years researching how to make a flameproof material, and finally has it. It's far more heat-resistant than the space shuttle tiles, far more durable, and far cheaper. A friend and I watched him testing it for a military representative last July, and got the whole thing on film (it was so interesting we hope to turn it into a documentary). His material would solve many of the space shuttle safety issues, and do it for cheap (and he has an impact-proof version as well, which provides a cheap way to prevent many of the deaths of soldiers in Iraq; that was the focus of the testing I saw).
Here's his site:
http://projecttroy.com.nexx.com/website/
The new tank has cameras that will allow ground workers to monitor for damage as the shuttle ascends
What are they gonna do about it when it is damaged from the ground?
And what are they going to do if they see damage, tell the crew to jump out?
Also, stop using the International Space Station because it can't get us to the moon, mars, or anywhere, and it is too expensive. It also has no scientific gain since it takes a full time crew working just to keep the thing from crashing into the ocean, exploding, or something else.
"The new tank has cameras that will allow ground workers to monitor for damage as the shuttle ascends."
Not much of a reassurance to the crew though, are they?
Ground worker #1: "Looks like she's breakin' apart."
Ground worker #2: "Mm-hmm."
Ground worker #1: "We install brakes?"
Ground worker #2: "Nope."
Ground worker #1: "Ejection seats?"
Ground worker #2: "Nope."
Ground worker #1: "... So, how about them Cubs?"
Are they going to send one of the astronauts on an EVA walkaround inspection before re-entering this time? Truckers check their brakes before a big hill, why don't astronauts check the heat shield?
Is it just me, or does this seem more like a patch than a real fix? Rather than realizing that the foam is problematic and designing something that won't come off, they resort to finding ways of preventing the old stuff from coming off. Well, if it works, great, but it just feels unsatisfying.
Perhaps this is just a case of extending the life of aging spacecraft a little longer for the least expense so that more funds can be routed towards newer technology that doesn't have the same inherent problems. (Perhaps different ones. *g*)
Not only that, but if you apply this bearproofing technology to the shuttle program, you are ready to go for the Ursa Major mission.
Don't blame Durga. I voted for Centauri.
We all know Canada doesn't have a military. Nice try.
Let me guess: they could have done this right from the start and a couple of engineers probably brought it up 10 years ago but were shut up by management?
Wow im pessimistic today...
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They've known about this problem for 20+ years. "But we never lost any important tiles." NOW they decide it's time to do something about the chunks of ice. If you needed any more evidence that NASA was a haven of groupthink, bureaucracy, and institutional cowardice, here it is.
Behold the riant ape! Beware, his crooked thumbs!
An AK-47 in the hand of the wearer would greatly enhance the ability of the ensemble see that no bear comes anywhere near.
Don't blame Durga. I voted for Centauri.
It always amazed me that everything for the space shuttle was probably manufactured by the lowest bidder for the given project due to the red tape involved.
Common sense would suggest that going with the lowest bidder might not exactly yield the highest quality product. Could have the space shuttle been built "better" had we paid more for it?
"There is a bear in the woods. For some people the bear is easy to see. Others don't see it at all. Some people say the bear is tame. Others say it's vicious. And dangerous. Since no one can really be sure who is right, isn't it smart to be as strong as the bear? If there is a bear."
Don't blame Durga. I voted for Centauri.
This was news last week, not today. Week old news posted as headlines is sad. Very very sad.
...for example, the shuttle could dock with ISS and the crew could take the Soyuz capsule down, rather than attempt a re-entry. They might not know the heat shielding was damaged without the cameras. Although it's still nowhere near the perfect solution (ie, scrap the shuttle).
The very last call I took at the IBM PC Help Center [which, I gather, is in peril of being relocated from the RTP to the PRC] was with the guy who administered the laptops that the astronauts took on the shuttle. Could only see about 100 of the 300 servers on his network, so we figured it was a networking problem [I was in networking, not laptops], and I spent three hours with him before we finally realized that it was the drivers for the PCMCIA bridge that were killing the ethernet stack. Updated the drivers and la voila - everything worked perfectly.
ANYWAY, this was early 1997, and he told me that the shuttle was filled with 8-bit processors dating from its design in the 1970s, and it was cheaper for them to have the astronauts carry light weight IBM laptops onboard as a form of an upgrade rather than ripping the beast apart at the seams and upgrading all those 8-bit processors to 32-bits [which I suppose nowadays would be 64-bits].
Wonder who they'll use for such sensitive equipment now that Big Blue has jumped in bed with Big Red?
I spent three hours with him before we finally realized that it was the drivers for the PCMCIA bridge that were killing the ethernet stack.
In retrospect, this was IBM in early 1997, so it might have been that the drivers for the PCMCIA bridge were killing the token ring stack.
Anyway, it was just about eight years ago, so be a pal, and cut me some slack...
Space is a red herring for recent administrations. They have no interest in space exploration because they well know the Rapture will occur here on Earth. Why jaunt around other planets when Jesus is coming home? It's far better (in their view) to spend money on Israel and wars, anything that helps contribute to the "End Times."
Space Shuttles generally do not carry enough fuel to reach the higher orbit of the ISS unless the mission is explicitly planned to visit the ISS (and thus have the additional fuel).
Also, only one of the shuttles has a large enough carbo bay to contain the ISS docking module, assuming it would be launch with the module on a non-ISS-visit mission.
Up, Up, Down, Down, Left, Right, Left, Right, B, A, START
I for one can't wait to see the explosions and breakups from that viewpoint.
Hey, a cheaper way to prevent many of the deaths of soldiers in Iraq would have been to never invade.
Since when did Cheap and NASA ever go together.
thank God the internet isn't a human right.
NASA's Shuttle Fleet was supposedly state of the art in the 1980s, although half the posts in this thread will tell you that perhaps they weren't built that well back then. The point is, why are they trying to correct the flaw in such an antiquated vehicle? The Space Shuttles are 20 years old; they belong in museums, not space.
Algore required that NASA use much less tightly-bonded non-freon usage insulation foam 'to protect the environment. That is when the foam started pealing off and damaging shuttles.
Yes, it is all Algore and the Earth-worshipper's fault.
Really.
Now with 20% less explosive decompression!
My other
Hello, is that Russia? Hi, well we managed to get our men into space ourselves this time, but err... haha, it's quite funny really, we might need a teensy bit of help getting them back!
And how about that re-usable space launch system in use on and off for 30 years..total failure. Maybe you can do it better ?
"I believe today that my conduct is in accordance with the will of the Almighty Creator"-Adolf Hitler or George W Bush?
Wake me when we get a launch system that actually goes somewhere.
You have two hands and one brain, so always code twice as much as you think!
Is the secret. Delta IV has the ability to loft heavy packages as does Ariane-5, Proton, Long March III and whatever the Japanese have ready.
Of course you need a serviceable profitable launch facility wherever you decided to launch from and whatever you decide to launch with. That's the real driver. NASA would need to develop a launch facility for Delta IV of the type and in the location that they can maximize their dollars income and minimize dollars per Kilogram cost.
The Russians have a similar problem with Dnepr in that they also want to abandon Baikonur and use Svobodny 18 in the Eastern Siberia. Problem is that Svobodny 18 is not built for Dnepr.
First for most orbital insertions they need a facility that faces the ocean to the east because that is typically the launch direction. Next, it can't be too far north or south unless its specifically designed for polar orbits (Hello NRO Keyhole spysats!!) Last it has to be multipackage capable as well like Ariane-5 in Guyiana which just sent up 7 different satellite packages from different customers.
Only way to make it pay without the One Gigantic Government Payload mentality that NASA has today.
If there had been a nuclear reactor on Challenger when it exploded, chances are no radioactive debris would have been released because the Shuttle wasn't atomized, large parts of it survived, the voice data recorders survived, hell the crew capsule survived intact until it hit the surface of the ocean, the crew's remains were intact, well until the fish got to them.
Nobody I know - including the redneck parts-swapping greasemonkeys - calls it "freon". They either refer to it as it's R (R-12, R-134) or by its brand name (freeze 12). Hell, freon hasn't been used in years, with CFC's replacing it in the 60's for non-commercial applications, and ammonia in industrial uses.
installed heaters
So your saying they put heaters....on a fuel tank?
Coder's Stone: The programming language quick ref for iPad
They'll just shut off the rocket engines and jave it come back down.
Civilians have put more into space in the last two years than nasa has in the last five. Eat that.
In the Challenger accident (1986) there was no problem with the tiles. The main investigator of this accident was no less than Feymnan himself. He traced the problem back to an O-ring (gasket) that became too brittle due to the extreme cold. All of this is described very nicely in part two of his autobiography What Do You Care What Other People Think?.
Z
Did you click on the links? Even your vague set of dim sensory apparatuses should have perceived I was joking. I am, in fact, a fairly big fan of NASA.
Welcome to 2005, everyone! Just as fucked in the head as any previous year! :-)
--- Ban humanity.
During the apollo program, they experimented with a wide range of materials. They found the best overall material was - get this shit - CORK. What every office worker posts notes to. After the initial layer of charcoal formed, cork sheilding could withstand over 900 degrees of heat. Unsatisfied with this approach, further research found that by grinding the cork up into a find powder, then encasing it in high temperature silica glass beads, they could construct a heat sheild which was still lighter than shuttle tiles, capable of enduring 2,700 degrees of heat, and cost far less to manufacture. This is the sheild used on the Opportunity and Spirit rovers.
So why isn't cork used on the space shuttle. Well, how would you like to tell your fellow engineers that your space ship has an arm made in canada and the bottom is lined with cork.
So let's all just wait for the elevator.
Let's also hope it isn't right around the corner, just like fusion power has been for decades.
I like the idea of the elevator - I'm just not waiting.
The living have better things to do than to continue hating the dead.
And what would be the plan in case they detect w/camera something was damaged during ascent? Let suppose a tile has been damaged or ripped apart, what we gonna do, send them a tile replacement on board a Ariane rocket costing 40million, which takes time to prepare and would be ready in five or six weeks. Then hopefully somebody from the shuttle crew is trained on external vehicle activity to go outside an do the job of replacing the tile. That would take another week of preparations!
In his books, Michael Flynn had a private space company building a light reusable launch vehicle that salvages a pre-destruction MIR. To expand the space station, they paid NASA to up the amount of fuel in the shuttle fuel tanks, giving the shuttle enough fuel to get even the tanks into orbit. The tanks were then pulled out by the private company's vehicles and attached to the MIR.
Is there any scientific basis for his suggestion, or is it impossible? Can the shuttle tanks be brought into orbit?
Remember when the shuttle main fuel tanks were painted white? They stopped painting them to save money.
I wonder: can ice chunks stick as easily to a painted fuel tank? You'd have to assume at a small scale the paint would fill in rough voids and provide a smoother surface, either preventing ice build-up or promoting shedding (like when the engines start and shake the hell out of the orbiter before it's flying).
I'm sure Coca-Cola would pay for a big red paintjob on the main tank with their logo. Or a Nike swoosh - there's great marketing potential here.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
The real problem is getting the government the fsck out of the way.
you reckon they send those tanks up only 4/5ths full, or that the tanks are over designed?
Sorry, but any spare capacity in those tanks is a safety feature, or due to payload considerations. Unlikely theres enough to get to orbit.
I thought the purpose of the suit was to repulse bears, not attract them for purposes of getting a pelt! Now, for what you need, to get a nice undamaged bear pelt, is a Cindy Bear suit and a great big sledgehammer.
Don't blame Durga. I voted for Centauri.
They now take unleaded instead of regular.
Perhaps the tiles should interlock like those sliding number puzzles, or tongue and groove flooring. That way, and individual tile adhesion failure wouldn't result in the loss of a tile.
"I'm not impatient. I just hate waiting." - My Dad
How well could a ground-based camera take a picture of the shuttle?
How about with all of the fancy adaptive optics that everyone says will render the Hubble expensively irrelevant?
How about if the shuttle shines a laser down to Earth, to help 'calibrate' the adaptive optics?
How about if the ground station could illuminate the shuttle with lasers, possibly with a series of colors to check specific aspects of the TPS condition? (Stay away from the windows, please!)
The living have better things to do than to continue hating the dead.
No, they primarily stopped painting them to save weight. So they wouldn't necessarily want to add the weight back to sell adverising space.
Why is Slashdot about a week behind CNN.com? http://www.cnn.com/2004/TECH/space/12/31/shuttle.f uel.tank.ap/index.html
And that, sir, was the perfect punchline for this joke. ;)
The owls are not what they seem
-- "Private industry should make it, not NASA!", private industry *does* make spacecraft. --
The debate is not weather federal employees build the shuttle or private contractors, but rather that private industry should PAY for the contruction, not public tax funds.
GOVERNMENT: Give us some money to explore outer space.
JOE TAXPAYER: No, I don't think it's that important. Besides, I'd rather spend this money on food for my family, or heat for my house, or invest it for my retirement, or half-life 2.
GOVERNMENT: We'll take you're money anyway. If you resist we'll throw you in jail. If you resist going to prison, we'll shoot you.
let's heat our fueltanks! What if the heaters become faulty and blow the hell out of the fuel tanks? What then?
If you like what I've said here, and want to read more, go to http://www.krillrblog.com
Keep this up and one day the shuttle will be too heavy to liftoff. In an STS, every pound counts.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
If you could take a vaccine for the common cold once then you'd lose all that money for cold remedies. And if you could cure high blood pressure, cholesterol, diabetes and arthritis instead of managing these conditions then you'd make much less money. It is the opposite of the old saying about teaching someone to fish rather than giving them a fish for dinner. In this case, they'd rather that you were dependent upon them for the rest of your life.
In the same vein, the shuttle is very expensive but this is good for the companies that essentially strip them down and rebuild them for every launch, which is what they do rather than just reusing them. The SRBs are salvaged out of salt water and rebuilt. The shuttle is a prime example of pork barrel politics and make work projects. It is meant to make political capital for certain states, not to solve a problem. The contractors love being the only game in town and since they can charge a margin on top of subcontractors and equipment and software bought for the projects they never use things over again, they buy it all from scratch. It is a large waste of money, but good for the economy in a way if you like having the gov't fund what amounts to corporate and personal welfare.
Until there is a completely private alternative, accountable to shareholders instead of politicians at the trough, space travel will continue to be outrageously expensive and inefficient.
$#!^ happens, but why does it always have to happen to me???
> They'll just shut off the rocket engines and jave it come back down.
That would be quite a trick, considering that solid rocket boosters (SRBs) CANNOT be turned off. The only option is to jettison them, and maybe turn off the shuttle's 3 onboard engines (which are liquid-fueled). And then there are the various ditching / attempted emergency landing plans that were nicely described in another post.
The main problem on the antiquated space shuttles is the heat-resistant tiles. They're extremely expensive, and not very good. They're so soft you could problably crush a piece with your hands, which means they're easily damaged during flight (and we've seen the fatal results of that).
Tiles get bad press because of some problems encountered during development in binding them to the skin of the orbiter. This problem was solved long ago. Tiles are covered with a silica glaze. You certainly can't crush one that is fully glazed with your hands. (I have a glazed white tile). Since then, they have performed admirably. They are remarkably light, heat resistant, easily worked. Furthermore much of the shuttle's upper half has been covered with a new nomex blanket insulation that aren't tiles at all. The insulation proposed for the x33 was also based on a strengthened silica tile. You will not see tiles be abandoned as thermal insulation for spacecraft.
It wasn't tile damage that brought Columbia down. It was damage to the relatively strong carbon-carbon leading edge. Any material hit by large speeding debris would be significantly damaged, even titanium. The engineering problem is debris shedding. Lets hope that is fixed and the shuttle can fly until the CRV comes online.
an ill wind that blows no good
You are misinformed. Columbia was the only shuttle that had issues with reaching the ISS. She was heavier than the other shuttles, and didn't have certain features necessary for docking, including the collar, IIRC. Well, we don't have that problem now, do we?
Every other shuttle has undergone maintenance specifically to be able to reach the ISS, and NASAs stated objectives are that no non-ISS flights will be made, with the possible exception of the Hubble repair flight.
It's somewhat misleading to say that the cameras will see damage to the shuttle if more foam breaks off. The cameras are mounted on the side opposite the shuttle! Why? Cameras were mounted on the Shuttle side of the tank on a previous mission, but the lenses got smeared sometime during flight. (SRB Seperation, IIRC) The purpose of these cameras is to assess ice buildup and shedding and shedding of foam from the external tank in general, not specifically what hits the shuttle.
It's my understanding that these new cameras, if they had been mounted on the Columbia mission, would not have seen the foam that hit the shuttle, except possibly (though not likely) as a piece of debris in the exhaust plume.
Cameras were never intended as a 'fix', but as a way of gathering more data to identify and understand this and future problems, from which a better 'fix' could be implemented, hopefully before another tragedy.
Yes, if these cameras had been mounted on previous missions, NASA might have had better data as to the scope and frequency of the problem, and maybe something would have been done sooner, and maybe the Columbia tragedy could have been avoided. The fact that they tried to mount cameras on the External Tank on a previous mission shows, to me, that they were aware of a potential problem, and tried to gather data to assess the risk.
The new rule is that all shuttle missions must be planned so that a docking with the ISS is possible. This reduces payloads and prevents some work, such as that which needs to be done soon on the Hubble Space Telescope.
In any case, work on the ISS is so backed up that I believe all of the coming missions are planned to be for work on the station. The shuttle has become half of what it was planned to be -- an inexpensive method of getting nominally mundane things done. It's an expensive construction vehicle now, the equivalent of a foreman's pickup truck, but made of gold.
You can never go home again... but I guess you can shop there.
1. The cameras arent new. Right now, the cameras on the tank are ATM cameras. They couldn't get the new cameras approved for manned space flight in time. These will be installed on future tanks (not the next one delivered, but probably the one after that)
2. Since the tank is actually a super thin aluminum shell with two more super thin aluminum shells inside of it (liquid oxygen and liquid hydrogen at something like -600 F) it needs insulation.
the foam was made to be more sticky and less prone to falling off.
The bipod (where the shuttle's nose connects to the tank) was espically prone to foam falling off of it and hitting the shuttle. So, what they did was put heaters in the base of the bipod to prevent the -600f tank about 2 inches away from freezing the thing solid.
The heaters only run untill just before liftoff, when the umbilical is detached and the shuttle launches.
Those are the two main things (the foam and the heaters) that the review commission required before they could fly again. Everything else is just extra.
Also, the shuttle is the mack truck of the space program. It can only go into Low Earth Orbit, not even into outer space. We need a better system. cspring
At least the cockpit electronics have been upgraded - to 32 bit computers (among others 386). I'd guess that that's just the part the pilots/astronauts interact with, the avionics is probably still the old hardware, which was not 8 bit, but something derived from IBM's S/360 line with 32 bit, but only 104k of proper core memory. If you want to know more, I suggest you read at least chapter four of Computers in Spaceflight: The NASA Experience
Because it's still well before the next Shuttle lift-off.
Tag lost or not installed.
Only recently have Pentiums and other processors of the same level been qualified for radiation hardening in space applications (at the manned-spaceflight altitudes, which are full of radiation). The current level of technology has circuit pathways that are too small and are more easily affected by the exposure. (http://www.sandia.gov/media/rhp.htm --> decision to redesign the Pentium was only in Dec '98 and it was expected to take 2-3 years.)
Either way, whatever they eventually design to replace the Shuttle after its decommissioning in 2010 (or shortly thereafter) will likely be designed with 1990's technology.
Actually ESAs mars mission is alive and kicking. Not only didn't you get the joke, but post jingoistic bullshit. Tsk. Tsk.
, so it's completely useless for "putting people in space to work on the equipment". As cool as Rutan's craft is, it is NOWHERE near what you need to do useful work in space.
Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
The shuttle design in use today was picked from several concepts in the early 1970's.
They purposely picked a design that required NO NEW TECHNOLOGY TO DEVELOPE in order for it to be cheaper to build.
One of the rejected designs was a 2 piece craft that was 100% reusable..... Yup, exactly like SpaceShip One today.
Another design was a 1 piece craft that was 100% reusable. But that requried development of high speed ram jets that no one wanted to fund.
The thing is, the US government can't really afford a space program. That's the core of the tax vs. private argument. It's not who builds it, it's not even who pays the bills, it's how the money's gathered together to pay them. Government is limited to a thief's budget: it can't make more than it can take. Private industry, which funds new investment from profit, can scale as large as it pleases, seeding each new project from the proceeds of the previous.
The next reusable orbiter will be built by Rutan. Because, only he can afford it.
It was a damaged heater in a cryogenic O2 tank that caused the explosion that nearly doomed the crew of Apollo 13.
Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
They're made up of beauracrats and government employees. "Civilians" work in the "private sector".
You ever get between a momma bear and it's cub? That's just asking to get an arse whoopin.
Wonder who they'll use for such sensitive equipment now that Big Blue has jumped in bed with Big Red?
You raise a good point there. I know sales of corporations have been blocked before by the US government due to security and sensitive infrastructure issues. Anybody out there know if NASA still relies on IBM?
The primary computers on the shuttle were, in the beginning, three "hardened" IBM 360 mainframes. The 360 used 8 bit bytes, and 32 bit "words", the smallest addressable unit. That said, Im sure that some of the auxiliary systems use smaller CPUs. As cool as they are, Thinkpads havent ever been used for critical systems. The reason why they use laptops to do word processing and note taking isnt because they cant upgrade their 1970s era electronic word processors, but because their 1970s word processors were paper and pen.
Were/are outside the shuttle mission specs; depending on your definition of 'deep', humanity is most probably *very* far away from reaching it. You
can blame the shuttle (designers) for failing to do something that might remain impossible/unfeasable for centuries to come.
Intersting point considering that the ESA module for ISS will stay on the ground until shuttle ops resume; certainly anything can be strapped on a rocket (ignoring possible avionic problems), but will it safely reach the desired orbit?
It's a rather costly option for satellite launch, I'll grant you that; but when it comes to recovery (not: deorbiting) and repair (think of Hubble) the shuttle offers unique abilities.
In the end I agree with you that the shuttle tries too much and thus can't do anything very well; but you make it look worse than it is. As a personal note: SS1 might be a 'little prissy ship', but it did what it was meant to do; reaching low orbit is certainly not an easy thing.
> the same grubby political reasons as before
By saying this, you make it clear that you know nothing of the history of the shuttle. The "grubby reasons as before" were largely varied, but mostly were due to budget cuts in response to the ever-escalating vietnam war. The project was told that they would be having a certain amount of money (the amount that they estimated they'd need, given the project at hand), and then came to find that they weren't, but the requirements on them weren't being lifted. As a consequence, they had to go begging to the air force, which in a way only made the situation worse.
> The thing is, the US government can't really afford a space program
Ah, I've got your argument now. The largest economy in the world can't afford a space program, but a man working out of a little shop can. Thanks for clearing that up.
> Government is limited to a thief's budget
Why are you bringing politics into this? This was a discussion about technical design issues, and at most tangentially about budgets during the design phase. What on earth do Libertarian rants have to do with this?
> The next reusable orbiter will be built by Rutan.
The next reusable orbiter will NOT be built by Rutan. Rutan is about as far from reaching orbit as the early americans were from reaching the south pole when they expanded to the southern tip of South America. It may look close, but there's hundreds of miles of trecharous icy water in between that they were unprepared to cross.
Rutan builds epoxy craft with purchased engines that were only cheap because they have essentially zero ability to scale up.
It's little more than a pressurized tank hooked to a ball valve that flows past an igniter into a tube filled with rubber, where gasses then expand into a nozzle and bell. A *real* rocket engine, one that can actually get you somewhere, is a hundred times more complex.
He has essentially no experience in most aspects of spacecraft design; about all he truly has under his belt beyond what any small aircraft builder has is experience in supersonic craft design.
Mind you, the next reusable orbiter might well be built by a private company. But you have absolutely no clue of the staggering scale of problems involved in reaching orbit and reentering. Strapping a simple rubber rocket on the back of an epoxy craft doesn't cut it. If it is to come from a private company, it will be from a *big* private company, which actually has *experience* in the field.
Seen on a Japanese food processor: "Not to be used for the other use."
Theoretically, yes. Depending on the mission profile, the tank isn't necessarily completely full, so there may be extra volume available. Whether or not it's actually enough to allow the shuttle to orbit the extra mass, I don't know. Assuming Mir's orbital inclination is anything like ISS (remember it's at a high inclination so the Russians can reach it from Baiknour) though, that margin is eaten into more since it takes extra fuel to launch to higher orbital inclinations. Plus you have to get the whole ball of wax to the right altitude. Higher altitude=more fuel=less margin. There could be ways around that...strapping on extra boosters like what's done with the Delta 4 and Atlas 5 heavy configurations, for example, although flight certifying such things takes time and money, unfortunately.
NASA would also need a reason to go to MIR. I doubt they would designate a special shuttle mission or four just to ferry an ET to orbit. Of course, the company could pay NASA a whole fuckload of money...
On a side note, I just finished reading Earth by David Brin. In it he describes some interesting ways of building infrastructure in orbit, notably building orbital stations using previously expendable launch vehicle components rather than by launching specifically designed Lego pieces. Rather interesting approach to things.
By the way, I'm not involved in the shuttle program, though I do do propulsion testing work. This is my own best guess. If anyone closer to the program would care to clarify, please do.
Also wanted to mention that when the tanks are released, they technically aren't empty either. There's still a little bit of propellant that is not dense enough to be used (too hot or not enough pressure to maintain engine pump functionality) or has been so thoroughly entrained with pressurant that it would start causing problems. Kinda like the gas tank on your car. There's still fuel left when it's "empty". What's liquid but not enough to feed the pumps and more has been kicked up to make fumes...not usable either. Difference is, you don't care about that extra little bit in your gas tank; you just go get gas. But for flight, you have to accurately estimate this amount left over because the rest of the fuel still has to lift it. More fuel in the tank = more of this overage. And there ain't a damn thing that can be done about it because it's physics, not government waste. (Unless you want to sic the OMB against $Creator, which might prove interesting...)
This was an attempt at humor - if a rocket ever were to have it's engines shut off, there's only one probable outcome. ("Hello? Is that you Gravity?")
>It's little more than a pressurized tank hooked to a ball valve that flows past an igniter into a tube filled with rubber, where gasses then expand into a nozzle and bell. A *real* rocket engine, one that can actually get you somewhere, is a hundred times more complex.
C on tent.cfm?ContentID=58
I know Jim Benson, had dinner with him a few months ago, and I can assure you that his engines have the potential for Earth to orbit applications. That you would diss on the SpaceDev hybrid motor like that shows that you don't know what you think you know. They have the mass fraction, thrust and unlike other rocket motors are restartable and non-explosive. Think about how much that can change the economics of spaceflight. The future is clearly with simpler engines, not complex monsters like the SSME. Even Northrup is back in the game - they recently tested a new version of the lunar module engine - 5 moving parts and 650,000lb thrust. Yes, 5 moving parts.
http://www.st.northropgrumman.com/capabilities/
Now, I agree that a very large company will build the successful reusable spacecraft. That company could very well be Rutan's t/Space (not Scaled Composites) - t/space being a collaborative of Scaled and several other small companies, funded by the same deep pocket that paid for SpaceShipOne.
josh
gigantino.tv - Heavy but weighs nothing.
> They have the mass fraction
They do *NOT* have the mass fraction. It has an ISP of around 250 sec, and since it uses nitrous, it has a proportionally heavy tank. Such a design does NOT scale up; physics forbids it. If you want to scale up, you're going to need both better ISP *AND* a lighter tank, both of which require a completely different fuel/oxidizer combo.
The thrust issue isn't important; you can always scale up. Restart is nice, but isn't mission critical. But ISP and tank mass *are* critical.
> not complex monsters like SSMEs.
Yes, SSMEs may be a bit overboard. However, 250 ISP and heavy tanks just plain doesn't reach orbit, either.
> lunar module engine
Enough said: LUNAR module engine. We're not talking about entering lunar orbit - we're talking about entering EARTH orbit and beyond. The challenge is vastly greater, and a SS1-style engine doesn't come close to cutting it.
However, what you linked wasn't a lunar module engine. It is a a booster engine for a liquid fuelled rocket. And it doesn't have "5 moving parts" - the page boasts about how each *pintle injector* only has 5 parts, excluding misc connection parts (seals, attachment nuts, bolts, washers, assumedly coatings as well). Yes, that is an impressive boast, and yet, this is just a tiny part of the system for a liquid fuelled rocket.
In short, a single one of these injectors, a *simple* injector, probably has about half as much maching work as all of SS1's engine. And even still, this Northrop engine will be forced to pay the price for this "relative" level of simplicity.
P.S. - While hybrids in general are less explosive than solid rockets, and can usually boast a comparable or better degree of safety than liquid rockets, what about SS1's engine? Can you point me to the results of their tests on the effect of catastrophic nitrous tank failure from their safety checks in their runup to full unmanned system integration testing? Did it shred the polybutadiene, causing a severe conflagration, or not? Oh wait, that's right, they never did that, nor did they ever have an unmanned flight test of the fully integrated system (even on a scaled down setup), but instead, launched a manned craft in high wind conditions causing the craft to roll unexpectedly in the wind shear and almost lose control, all because they didn't want to disappoint the crowd watching below. How dare they lecture *anyone* about something being "safe" when they disregard safety like that.
Seen on a Japanese food processor: "Not to be used for the other use."
Yes, the reasons were grubby and political. In fact, your denial listed most of them, omitting only the part where the manufacture and assembly is scattered around as congressional pork.
"The largest economy in the world can't afford a space program"? No, the contrary is exactly my point. The economy - the private sector - can afford it. The government cannot.
The government can only take - politics aside, that's a fact. So, it's limited to a "thief's budget". There is a limit to what it can politically plausibly tax (and it's already pegged on the red line in regard of that limit). And there's a limit to what it can tax at all - the money that everyone else has produced to date. Because of the first limit, the private sector already - by unavoidable necessity - dwarfs the government's purchasing power. But in addition the private sector is not bounded by the second limit. It can actually create new wealth via profits and invest it to fund new ventures.
NASA has all the budget it's likely to ever get, give or take inflation and growth of the tax base.
In a century's time, even if NASA is maintained gung-ho, full steam ahead, it will be the smallest of small fry compared to the private space sector, because it cannot grow. Realistically, "NASA" will probably end up being a logo stamped on cargo crates, carried by private firms.
Sorta reminds me of Nasa launching a shuttle when the ambient temps were well below the rated range for the SRB, only cost 7 lives, but they had a launch schedule to keep. As for the unmanned tests, I am trying to remember when a fully integrated shuttle stack was launched unmanned for testing purposes. Oh wait, that's never been done. The first time Nasa built one, they strapped 2 guys in the cockpit, lit the fires, and launched it into orbit.
On the bright side, Nasa has _finally_ figured out how to make the shuttle stack safe. Keep it chained to the ground, and spend the entire budget writing reports as to why it cant be flown yet, and generate excuses to keep pushing back the 'return to flight'. Very sound strategy for a risk adverse management team, but really lousy bang for the tax dollar.
Yeah, we probably saw upwards of 50/50 Ethernet/Token Ring at the IBM PC Help Center circa late 1996/early 1997.
But I bet we saw a greater percentage of Token Ring than anybody outside of maybe Madge...
Yeah no shit they gave them laptops. What do you think, they ripped open the wall of the shuttle and put in a plasma TV and an Alienware system?
If that's too much typing for you,(without any spaces put there by Slashdot) yields: http://www.st.northropgrumman.com/capabilities/Co
Oh, and for you "Well just right-click on the text and click 'Follow Link'." people, tell me how to open a selected-text link containing extraneous Slashdot spaces in a new tab using Mozilla, or shut up.
Rei-
f o. cfm?ImageID=46
Mass fraction issues: spacedev is planning on using same tech for an orbital launcher, I'm not privy to the details but they are in process of resovling those issues. I'm pretty sure it won't be SSTO, it will use hybrid engines. Check out their "Streaker" vehicle design - yes it's press-ware for now but they are actively working on orbital launchers. Whatever the solution, they have something to solve the mass fraction issues.
>Yes, SSMEs may be a bit overboard. However, 250 ISP and heavy tanks just plain doesn't reach orbit, either.
True, but SpaceDev is working on it. So are Rutan/Scaled/tspace, SpaceX, XCOR and several other small shops. All their engines are simpler than SSME, RS68, etc. Of the big corps, there are several examples of new simplified (liquid) engines. CAD/CAM and new materials seem to allow better, simpler engines.
>Enough said: LUNAR module engine. We're not talking about entering lunar orbit - we're talking about entering EARTH orbit and beyond. The challenge is vastly greater, and a SS1-style engine doesn't come close to cutting it.
The Northrop TR106 650,000 lb thrust engine is based on their lunar ascent engine, not the Apollo CSM engine. The new engine seems large enough to serve in a primary stage of a launch vehicle. OK, so I might have over-sold the parts count, but it is vastly simpler than other extremely large engines like SSME and F1. The description below indicates that it has a single pintle injector.
better photo and description:
http://www.st.northropgrumman.com/media/ImageIn
>P.S. - While hybrids in general are less explosive than solid rockets
On failures - not sure how much catastrophic testing they did, but it was enough to fly successfully many times. They are both creating a new field/era of flight and doing some barnstorming. Yes, it's dangerous but they are a media product as well as Square Jawed Engineers. They probably shouldn't be lecturing anyone on safety.
Hybrids generally - the biggest safety issue with hybrids seems to be fuel lodging in the motor's nozzle. This happened on an SS1 flight (13p, I think), it caused a loud bang and dented part of the engine cowling. The appeal for manned flights is that when they fail, it is not a catastrophic failure. Unlike liquids or solids.
As it stands, though, none of this changes the fact that the only manned spaceflight program functioning in the US is based around Burt Rutan.
Josh
gigantino.tv - Heavy but weighs nothing.
> launching a shuttle when the ambient temps
> were well below the rated range for the SRB
Exactly - it's just like that. Except, the NASA engineers making the decision didn't have the data about the effect of cold on O-rings, while Rutan was quite well aware of the windspeed, and as a longtime aviator, should be very well aware of the dangers of wind shear (NASA routinely cancels launches, at big financial loss, if they think wind shear might be too high).
> I am trying to remember when a fully
> integrated shuttle stack was launched unmanned
> for testing purposes
Unless explicitly stated, all tests were unmanned. Only major tests listed; there were smaller tests going on almost daily. Tests listed for all shuttles being worked on at the time. I've probably left out some major tests, too, but I don't have forever to assemble the list.
Feb 15, 1977: Complete mated ground vibrational tests of airframe
Feb 18, 1977: The first unmanned captive flight of airframe (no engines)
Feb 22, 1977: The second unmanned captive flight (like above)
Feb 25, 1977: The third unmanned captive flight
Feb 28, 1977: The fourth unmanned captive flight
Mar 2, 1977: The fifth unmanned captive flight
Jun 7, 1977: Unmanned fully integrated ground fire test
Jun 18, 1977: First manned captive flight
Jun 28, 1977: Second manned captive flight
Jul 26, 1977: Third manned captive flight
Nov 15, 1977: First ferry flight test
Nov 16, 1977: Second ferry flight test
Nov 17, 1977: Third ferry flight test
Nov 18, 1977: Fourth ferry flight test
Dec 9, 1977: Complete approach and landing tests
Apr 21, 1978: First static test firing
Apr 24, 1978: Precombined systems tests
May 19, 1978: Second static test firing
May 30, 1978: Vertical ground vibrational
May 19, 1978: Third static test firing, 90% thrust
Jul 7, 1978: Fourth static test firing
Sep 20, 1978: Launch configuration vibrational testing
Jan 30, 1979: Start burnout mated vertical ground vibrational tests
Jan 30, 1979: Start orbiter mated vertical ground vibrational tests
Feb 3, 1979: Complete combined systems test
Feb 26, 1979: Complete mated vertical vibration systems test
May 4, 1979: Fifth static firing test (cont'd. Jun 12)
Jun 15, 1979: First SRB qualification firing
Jul 12, 1979: Sixth static firing test (Cont'. Oct 24)
Aug 6, 1979: Complete limit test
Oct 5, 1979: Complete setup and thermal tests
Nov 4, 1979: Static firing
Nov 12, 1979: Complete OMS qualification tests
Dec 16, 1979: Orbiter complete integrated test
Dec 17, 1979: Static firing, full 554 seconds, 100% power output, with proper reduced scaling and gimballing tests
Jan 14, 1980: Complete orbiter integration tests
Feb 14, 1980: Final qualification firing for SRB
Feb 28, 1980: Yet another full length static firing
Mar 20, 1980: And yet again.
April 16, 1980: Static firing again
May 30, 1980: And again
Jun 1, 5, and 16: More tests, this time for Colombia
Jul 12, 1980: Another firing test - and thankfully they did so many, because with how unpredictable rocketry is, they got burnthrough on this one, and were able to know about a potentially lethal problem and had time to rectify it.
Dec 4, 1980: Another static firing
Jan 5, 1981: Emergency egress test (manned)
Jan 17, 1981: Another static firing
Feb 2, 1981: Wet countdown test simulation
Feb 4, 1981: Continue a series of them
Feb 20, 1981: Flight readiness firing
Apr 12, 1981: STS-1 (manned, of course)
Those are the tests on the main shuttle craft. The 1/4 scale model underwent, to some degree, all of the tests listed above, plus full flight tests. Quarter scale models were built of both the SRBs and the orbiter. Needless to say, they were unmanned. They completed testing on Mar 31, 1980.
Here's Rutan's test suite:
A small series of unmated unmanned static test firings; no mated test firings that I am aware of, and I can't find anything online about any.
Seen on a Japanese food processor: "Not to be used for the other use."
> same tech for an orbital launcher ... which is impossible. Polybut/nitrous does not have enough ISP, period. Nitrous tanks are too heavy, period. Unless you mean "completely different tech" when you say "the same tech", you are completely incorrect.
... is not Rutan. Rutan has a rocket joyride company. Yes, he wants to reach orbit eventually, and that's a nice admirable goal. But he has nothing of the sort either on the ground or flying.
> All their engines are simpler than SSME, RS68, etc
And have the performance of a V2. V2s will never reach orbit, either. The extra complexity in SSMEs, RS68, etc, is not for no purpose. Yes, they're not the be-all, end-all of rocketry, but they at least have the *capability to reach orbit with any relevant amount of payload*
> OK, so I might have over-sold the parts count
It was obvious that you had before even reading the article. At the bare minimum, if you want a liquid fuelled rocket to perform well at all, you need a turbopump - pressurized tanks just weigh too much. Even the simplest theoretical design of a turbopump is still a fairly complex beast, and very sensitive to conditions inside the rocket. If I ever get into metalworking, I have a design for a theoretically simpler turbopump that I'd like to try out (an electric reluctance motor-driven one - no driving turbine, no seals in your fuel/oxidizer lines, etc), but even it would still be quite the piece of work, and unless I want to go SSME-style and have it staged, it won't perform as well as engines like SSMEs do.
See how these tradeoffs work? You can't get ISP for free; if you want a cheap engine, you can take a polybut/nitrous engine. If you want an engine that will get you to orbit? Tough, it's not going to happen. The ISP is too low and the tank mass too high. Anyways, back to the TR-106.
Not to mention that this is a LH/LOX engine. Are you aware of the difficulties in working with LH? Hydrogen embrittlement. Uneven boiloff. Insulation application (which has been a pain to NASA as well as other agencies, and one of the reasons why the Russian kerosene rockets, despite their much lower payload fraction, are so cheap). Pressure regulation. Temperature regulation. Hard to ignite when cold. And the obvious issue of the huge bulk size.
BTW, it doesn't have a single pintle injector; it has a single *fuel* injector. How do I know that there will be at least two injectors, ahead of time? Again, it doesn't make sense without that; liquid biprop rockets work by burning fuel and oxidizer. Both enter through "injectors". The more you preheat your fuel and oxidizer, the less complex of an injector you need, but then you need a more complex preheater. See how these tradeoffs work?
About the least "injector" you could get away with would be a simple hole in the combustion chamber attached to your oxidizer line, and you might get away with calling that something other than an "injector", but if you do that, you better have your oxidizer preheated or it'll never mix well.
> not sure how much catastrophic testing they did
As far as I am aware, it was *zero* catastrophic failure testing. They did a nice testing suite of glide tests, but the tests that they made public (and why on earth someone would hide something that makes them look safer - more testing - from the public, would be beyond me...) concerning their rocket engines are little short of embarassing. They did some non-integrated ground static firings, and after that they were firing on a fully integrated craft, midair, with a pilot in the cockpit.
Yeah, they're Square Jawed Engineers. And I admire that spirit, and I know that their test pilot supported them all the way. And the design has the potential to eventually be a very safe, reliable joyride. But I hope that everyone who straps themself into crafts like this know what they're getting into.
> the only manned spaceflight program
> functioning in the US
Seen on a Japanese food processor: "Not to be used for the other use."
--
How dare they lecture *anyone* about something being "safe" when they disregard safety like that.
--
And the Space Shuttle has a good safety record in comparison??
2 failures in >100 launches is the best record for any manned rocket with a statistically significant number of launches under its belt.
Seen on a Japanese food processor: "Not to be used for the other use."