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X-33 Shuttle Problems
SEWilco writes: "This AP story points out major problems with the X-33 prototype shuttle. It's out of money and the composite hydrogen tank came apart in a test. The aerospike engine test seems to be doing nicely, but it needs a ship attached. Congress is considering NASA's Space Launch Initiative Program, which apparently includes more X-33 funding along with considering other technologies. The Delta Clipper is my favorite, although the ET Scenario engine-only-return design is interesting."
Here is the link:
SciAm Space Exploration Issue
And, no it isn't a goat sex link.
I'm actually on the NASA team working on the X-33, I've also done some work on the NP-19. I've never had very high expectations for the Associated Press, but their errors in that article are unbelievable. First, we are nowhere near running out of money. The hydrogen tank component did come apart during one of our tests, but was repaired quickly and is now working fine.
In the end, I have no question that the next-generation launcher will be built by private industry either in the US or more likely overseas. Sad, but that's the way it is.
The funny thing is that, on the one hand, while NASA is doing everything it can to squash privately funded space initiatives in this country (while publicly attempting to appear to "help" them), while on the other hand NASA is held in such high esteem in the rest of the world that if NASA says something can't be done, nobody will even attempt to prove them wrong.
Sometime I expect to hear that Japan or China is building a DC-X style full scale prototype SSTO vehicle and I don't know if I'll laugh or cry.
On the other hand, the Delta Clipper, funded by McD primarily;
Actually, it was funded by the DOD as part of Regan's SDI project. There's nobody in the upper levels of McD management (or Lockheed for that matter) with that much vision.
Thanks for this dose of great info. I hope that one gets modded through the roof :)
At first I thought that wasn't possible, because the Space Shuttle and Venture Star don't have enough lift for take-off, only for a one-shot landing. But as you said, it won't need nearly as much wing surface to get enough lift to get off the ground, because it can lift off on virtually empty tanks with lots of payload, and refuel in the air.
You can improve the fuel to payload ratio even further if you put a refueling station in orbit. Then you can take off with enough fuel to reach the tanker aircraft, then top the tanks off - enough to reach the refueling station in orbit, and then take in enough for orbital manuvering and re-entry.
)O(
Never underestimate the power of stupidity
Never underestimate the power of stupidity
To err is human, to moo bovine
This is probably all pondered out by rocket scientists, but why not use a flying first stage?
:)
The big problem of a vertical launch is that 80% of what you lift is fuel, and is spent on the way up. Why not put an SSTO craft like the Venture Star as a second stage on the back of a big and fast aircraft, a modified 747, 777 or Beluga for example? Simply fly that aircraft as high and as fast as it goes, maybe stick a rocket on it to gain some extra height and velocity at its ceiling to launch the second stage.
As I said, it's probably been thoroughly researched already - if so, can somebody explain why this isn't done / doable, while it seems so simple and feasable (too simple?) to simpleminded me?
)O(
Never underestimate the power of stupidity
Never underestimate the power of stupidity
To err is human, to moo bovine
How much would it cost to get from Earth to Mars using current technology?
According to NASA, $50 billion to get there and back on the Mars Reference Design Mission '93.
Hint: there haven't been any realistic estimates below $100 billion, and some have been as high as $400 billion.
Er, you don't think NASA's Mars Reference Design Mission '93 cost estimates are realistic?
Steven E. Ehrbar
There's one very simple way to find out if it will work. One of the goals of Mars exploration is the "Mars Sample Return Mission" - dig up some Mars soil and Mars rocks, put it in a capsule, and send it back. Now, if you used the fuel-making techniques proposed by Zubrin for this mission, you'd get a Mars Sample Return mission done for approximately half the cost of the original mission (because instead of needing two launches and on-orbit assembly to get the mission off Earth, you could do it with one), and validate the technology for a future manned Mars mission.
I'm personally fairly confident that the fuel-making would work (the technology is fundamentally simple, and the Mars atmosphere has already been fairly well analyzed) but this is a great way to find out.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
I wish that the X-15 program had been extended another 20 years or so. If it had been, we would have had a vehicle that launched from a Bomber with a 1 or 2 man crew, that could reach low earth orbit.
If you wonder what good an X-15 type plane would be if it could only launch 1 or 2 people at once, then consider that it would be much better than our current cheap launcher which doesn't exist. A cheap launcher that can send a single person up is better than an expensive launcher that can send 7 people up.
Launch your heavy mass on Titan IVs and Energias. Launch people in small launchers. Have then rendesvous in orbit. It's cheaper that way.
If tits were wings it'd be flying around.
The big thing was the avionics system. Remember, before the Delta Clipper, there had never been a rocket that had landed like that, or had pitched over 90 degrees (well, they had, but they all blew up).
The DCX was really amazing. If it had been built, it could have been the first craft to be able to take off from the Earth, refuel in orbit, fly to the moon & land, refuel there, & come back. And it could land pretty much anywhere on the planet you had a big enough flat space.
It's typical of the government and McDonnell-Douglas's luck at the time. MDC has a proposal based on a previous, successful technology demonstration, then Lockheed gets the contract & fucks it up. Ever heard of THAADS?
The Delta Clipper also fell down and went splat quickly followed by a boom. Vertical landing is NOT a more economical way to land something. An aerodyne style ship can be designed to land on a commercial airport runway if need be and needs little or no fuel to land (watch the current shuttle land sometime) while a VTOL craft needs tremendous amounts of energy (fuel) which requires greater complexity and therefore greater bulk. The more bulk you've got the less cargo you can carry. It's more efficient to leave complexity to external devices rather than internalize them. External components are much easier to change around which means you can have a fleet of relatively simple (cheap) shuttles that carry your payload and then figure out cheaper and more efficient ways of getting them space-born.
I'm a loner Dottie, a Rebel.
Back a long time ago during the Gemini days there was a little project called Blue Gemini which was the Air Force giving NASA cash and research and whatnot in return for training Air Force pilots in space operations. At the time the idea was that the US and Russia would be getting into Buck Rogers style space combat. Alot of space based weaponry was thought of, once the first satillite went up it was all anyone could do to design a weapon to stick on one.
Usually, when a lot of men get together, it's called war.
-Mel Brooks
I'm a loner Dottie, a Rebel.
Because the Feds think that the moonshot was just an expensive way to thumb our noses at the Soviets. The people who REALLY got something out of the moonshots (that'd be the planetary scientists) can't WAIT to get back.
Why yes, I AM a rocket scientist!
Wow, this is a catastrophically bad idea. LEO is at Mach 25. Fastest known "conventional" jets nowadays are Mach 3. You want to tie them together, snag them with a hook traveling at a relative velocity of Mach 23, and drag 'em up into orbit? I bet the airframes would make a noise a lot like the monkey with the clapping cymbals, just before killing everybody involved...
You're not far from another interesting idea though. The nutty geniuses over at Tethers Unlimited want to have a mini-space elevator, whose bottom half is ripping through the upper atmosphere at about Mach 17. You dock with this thing from your hypersonic passenger liner (like the X30 that got canned, and for good reason), and hop on up into space on a great big crane.
How you actually DOCK at Mach 17 is not something I'd care to contemplate. But the idea's there...
Why yes, I AM a rocket scientist!
Thank God theres someone else here paying attention to the actual programs and problems, instead of the hype put out by LM. Sucks about the DC-X/Delta Clipper, seems like it was about the best idea around. But no, NASA just had to go with the most unproven concept...
What do I do, when it seems I relate to Judas more than You?
Still not dead.
Yeah there are problems with the X-33- we're still not at a point where it makes sense to have a single stage to orbit spacecraft!
So it sounds like a great idea... everything is reusable, and if it works on cars and planes, then why not on a spacecraft? But you have to take a *lot* of fuel along. The reason staging works is that what you're pushing gets progressively lighter as you go. Yeah, its wasteful, but it works, damnit. If you want something really nice, design a two stage rocket with both stages reusable.
What you get with current tech is a really big fuel tank, pushing up a comparatively small payload.
What do I do, when it seems I relate to Judas more than You?
Still not dead.
How much would it cost to get from Earth to Mars using current technology?
Hmmm... let's see if I can dig up the GNP of Spain in 1492, so that a relevant comparison can be made....
/.
/. If the government wants us to respect the law, it should set a better example.
While never actually, built or tested, such a plane was designed, to use "coal (or paraffin coated lignite dust) for fuel", according to the following site:
http://visi.net/~djohnson/lippisch/lip13b.html
BTW - Check out other planes on this site - very strange stuff!
I support the EFF - do you?
Reason is the Path to God - Anon
`Cheap' is not what I would call several-thousand-dollars a pound. I could see calling several-thousand-dollars a /person/ (a day) cheap, but that's not even within three orders of magnitude of current launch systems. The Shuttle can meet the needs of the ISS only because NASA is willing to throw so much money at it. I assure you that NASA and Congress would be more than happy to cut the cost of the ISS by a third using SSTO or other 10x-cheaper-to-orbit technologies.
/shuttle/ was intended to launch roughly once a month, but because of design missteps, required a time-consuming external fuel tank and solid rocket boosters. A launch system without external tiles that just needs refueling would be much cheaper to operate because you'd need many fewer of them.
The other issue is turn-around time. The space
Incidentally, having water ice is very important for space exploration, because it removes the need for about half of your consumables. (Water can be drunk and used for hydroponics; cracked water can be used for fuel and to breathe; raw ice, if there's enough of it, makes a good dust shield, etc.)
-_Quinn
Reality Maintenance Group, Silver City Construction Co., Ltd.
Just a quick link that seems highly relevant to this story but is missing (last I checked, a few seconds ago)...
The X PrizeFrom their site:
The purpose of the X PRIZE is to promote the development and flight of spaceships able to provide low-cost commercial transport of humans into space.
No Laughing Allowed!
User Bio
Visual effects programmer/animator/supervisor Developing visual effects tools for Linux
While that's a nice thing for Thagg to be doing, I can confidently say that he's talking out of his ass. NASA has been doing good things with its ever shrinking budget and the directions it is given. If you want to point to politics, look in the mirror.
The X-33 was a risk, but not nearly such a stunt as the Delta Clipper, which had a marked tenedncy to explode. Think about vertical landing for a minute. Parachutes and gliders can be made stable much easier than the DC. Vertical landers are also the least efficient of rockets. If it took a Saturn 5 to get to escape velocity, it will take a Saturn 5 to stop a vertical lander at escape velocity. Now what would it take to get a fully loaded Saturn 5 to escape velocity? Orion, that's what.
The X-33 was not all worked out when it started, what is? The technologies being tried are mostly involved with new materials. They have benifits that could greatly reduce weight and that equals cost to put things in orbit.
Carbon fiber technology has great promise and has worked it's way into all sorts of parts already. Fiber is to aluminum what aluminum was to steel. Parts can have 1/5 th the mass of their aluminum equivalent. I'm not sure why they have been having so much trouble with those tanks, but I know from a friend that works at Michaud that there have been problems like this for the last three years. I suspect heat curring just induces too much strain for cryrogenic tanks, and I wonder why they have not tried to use E Beam curring another Lockheed Martin technology. Oh well.
As for politics, we could have used Appolo technology to get to Mars by now, or Orion to get even further. But, we the public are full of bad advice.
To learn more visit and or join:
AIAA
SPE
well yes and no, the white tanks are reused but they can only be reused for a few times, after that they have to be scraped, but at least thats better than them not being reusable at all
Tell me what makes you so afraid
Of all those people you say you hate
Okay, slow down for a minute and calculate exactly what you've proposed; make sure you account for the fact that the vehicle is very lightweight and almost empty (hint: W/[Cd*S] is not large).
What you'll find is that the vehicle is its own parachute! Depending on the exact details, terminal velocity turns out to be around a couple of hundred feet/second -- it only takes a few seconds of thrust at a reasonable level (say 2 gees) immediately before landing to bring that to zero.
This is actually quite well-known -- I don't know why you aren't aware of it, unless you're just ignoring it. DC-X was a damned fine project, and it met its goals; only when NASA took the reins with DC-XA did things go to hell. I leave it to you to speculate on the reasons...
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Politics is about making compromises. Religion isn't. --Michael Horton
The moonshot was just an expensive way to thumb our noses at the Soviets.
If going to the moon had any intrinsic value, why haven't we been back since the early seventies?
Do they not teach math at the University of Kansas? Try looking up the distance to Mars next time you toss around your useless anecdotes.
By the way, Columbus was not the first European to reach America (but I wouldn't expect you to know that either).
Prohibitive costs in research and development are not going to stop SSTO ships,
You're right, physics is.
Soyez is just a orbital taxi, and the Protons, Arians, and Deltas of the world are too few to go around.
Thats garbage, you have no idea what you are talking about. From refurbished SS-18s, to Sea Launch, to Arianne, there are numerous ways to put your satellite in orbit, and they're getting cheaper all the time. The X-33 was never intended to be used as a satellite ferry anyway - NASA knows it will never be the cheapest satellite delivery service, and they aren't even in that business anymore.
Ok, pop quiz:
How much did it cost to get from Europe to America?
How much would it cost to get from Earth to Mars using current technology?
Hint: there haven't been any realistic estimates below $100 billion, and some have been as high as $400 billion.
Comparing a trans-atlantic journey to a Martian journey is a stupid comparison, and it would behoove thinking people to drop it asap.
The X-33 was pure gravy, just like the ISS. Now we're going to have to pay through the nose for the next fiteen years so a succesive groups of Russian astronauts can learn how to take a crap in a weightless environment while doing nothing useful at all.
The real question you have to ask is why bother at all. We can already put up satellites cheaply - there is no need to create new technology to meet this need. The shuttle or the Soyuz capsule can meet all the needs of manned orbital flight and the ISS (another boondoggle) for the forseeable future.
What else is there? Mars? Newsflash folks, its a rock floating in space with some ice on it. Waste of a trip. Until we develop drastically advanced propulsion technologies that in no way resemble anything we are even thinking of now, space is simple a gigantic lonely space that is off limits to us. Astronomy is a far more useful and realistic way to explore the heavens.
747s never have to attain escape velocity - they need only to become airborne. They can also make use of lift - which is mostly meaningless with regards to current and proposed orbital designs.
Attaining escape velocity means going fast - very fast - the shuttle hits 17,000 mph in order to achieve orbit. This take fuel, and a lot of it, per pound of payload. But the tricky part is that your fuel becomes part of your payload - the more fuel you carry, the more you need to propel it. Staged designs have typically been a solution to this problem - each stage is only powerful enough to get the stages above it to a certain point in the atmosphere - when this point ius reached, the stage falls away (reducing the weight of the vehicle).
There's nothing stopping us from getting to orbit, or Mars for that matter, it's just the price that would be involved doing it safely enough to prevent disaster and maintain NASA's reputation.
Not true. There are some serious opinions claiming that SSTO is simply not workable given the technologies we are developing - the physics simply cannot be overcome unless we develop dramatically lighter materials and more effective propulsion.
As for Mars, we do not have the technology available right now to get there. Zubrin and co. may have designs which seem workable, but they are only designs. No one knows if generating return fuel on the Martian surface will actually work.
Also, for the political and Economic musings related to getting in space, check out this article, also on space.com.
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on the moon for a few days at a time, come home, and stop.
We saw our space station built in Houston,
orbiting too low and too slow, at ten times the cost.
Thirtieth anniversary of the first man on the moon,
celebrated by grumbling.
My tee shirt bears an obsolete picture
of Freedom space station and the legend,
"Nine years, nine billion dollars,
and all we got was this lousy shirt,"
and it's years old and wearing out.
Now is economics interesting?
-------------
---Mike
harlock@raindrop.com
Preferably with an extra terrestrial government. Nothing spurs rocket technology like a really good war. Since the end of the "cold war" we've had no real impetus to improve our rocket technology, so all the funds get diverted to more visible projects. Of course, the "cold war" was fine, but there's nothing like a really good "hot war", to put the fire to congress to fund research.
List from the top of my head:
In short, the attitude that Mars is just a ball of dirt and ice is exactly equivalent to the French and the Russians regarding Louisiana and Alaska as a lot of worthless wilderness. (Until recently, the Russians thought that way about Siberia as well, but they wised up before they sold it to anyone.) Had a realistic value been set on either of those territories, the United States would never have been able to afford either.
-- AndrewD
A Maze of Twisty Little Laws, All Different.
Let's get Thiokol on the job. They'll get that baby launched!
"If I have seen further than other men, it is by stepping on their glasses." - Michael Swaine
Get two of the highest fastest conventional jets you can find, fly them to the limits. Stretch a long wire between them. Take a conventional spacecraft that is already in orbit bung in a big reel of wire type stuff with a hook on the end of it , bring it down to the level of the conventional jets and point it towards the middle of the wire streched between the jets and connect the hook. then as the reel starts to pay out, apply some sort of braking system to the reel on the space craft, this way you could controllably pass the velocity of the spacecraft to the velocity of the jets. Sort of like using the principle of the catapault on an aircraft carrier, another idea is building a flying slingshot. I know these ideas will be probably be thought crazy, but has any body done a feasability study? Its all maths and materials technology not something I know a lot about. But if the wires had a high elasticity it would help a lot.
Drastic problems require drastic solutions
It's called an elephant's trunk whereas it is in fact, an elephant's nose, a nose by any other name would smell as sweet
This sure is a blow to the air transit field, seeing that they haven't had any advances in technology for over 35 years. But, if a first you don't succeed, try try again. (no, not "if at first you don't succeed, sue the pants off your competitors!")
"Ancillary does not mean you get to rule the world." --U.S. Circuit Judge Harry Edwards, speaking to the FCC's lawyer
While I don't claim to understand the physics involved in this myself, I found G. Harry Stine's explanation of the science involved convincing. In his account of the development and testing of the DC-X rocket, "Halfway to Anywhere", he describes how there are designs that prove SSTO's feasibility (given a few new technologies), while there still are scientists claiming that this is not true. Everybody has their axe to grind and their own agenda, and the book does a good job of presenting them. It's somewhat proselytizing at times, but a good read nonetheless
-- H. Wilker
The answer to all our space program problems traces back to capital errr capitol hill. Space exploration is not regarded as a major issue to the bourgoise that run our country. They would rather use their power to deepen their pockets than to explore the heavens and to better mankind. Yes, there are more important issues like social security (I really would rather not start getting my check after 143.5 years old). We have a lot of shit that we don't really need that could send us all the way to Mars and back enough times to get a colony there complete with Starbucks (the true sign of civilized life). The answer is simple, cut defence. Although their toys are cool, they're rediculously expensive and not needed. All the B2 bombers have done is bomb the hell out of civillians to make their policy makers yeild to our Imperialistic demands. Missle defence won't work. It is fighting the long dead cold war and luling the public and govenment into a false sense of security like the Maginot line did for the french (look it up, it's an interesting story). We need to get the government out of building this worthless shit and building stuff that will help humankind. We need a challenge like John F. Kennedy's to this country to spur public interest and get money and resources to our space program and other more useful programs.
X-33, like all space projects cannot express its potential benefit for the average dependent in a 60-second sound bite. If it weren't for the fact that these programs are spread out among so many influential congressmen's districts, they wouldn't be funded at all. Spending money on anything other than welfare or programs with a me-right-now benefit for the voters doesn't have a chance.
The fact that it could lead to a place for their great-great...grandkids to live other than on a burned-out, over-crowded planet means nothing. It doesn't put money in their pocket now, that's all that matters. What they don't realize is that we are where we are today because of advances made in the space program of the 60's. Computers, plastics and myriad other things we have benefited enormously from that program.
The money spent today on the space program primarily benefits specific people in specific congressional districts. I don't see how we can get back to the way things were in the 60's space program in today's culture. Advances will almost certainly have to come from the private sector. I still have a certain amount of respect for NASA, but as the saying goes, "lead, follow or get the hell out of the way." If they aren't allowed to lead us into space then they should get out of the way of private industry.
X-33 info: http://x33.msfc.nasa.gov/index.html
X-30 info: er, I can't find any in three minutes of searching. However there are some pretty pictures.
--
"I have also mastered pomposity, even if I do say so myself." -Kryten
--
"I have also mastered pomposity, even if I do say so myself." -Kryten
I often try to decide whether space exploration is comparable to the sea voyages undertaken by 15th to 18th century mariners. These voyages were comparable in risk to today's space flights, even flights to the moon and to Mars. Back then, I guess, the motivation for these explorative voyages was partly commercial, partly just human curiosity. Admittedly, they did know that there were spices to be found in India. We (pretty much) know there's water on Mars - let's go there and see what we can do with it!
But no, we don't need to invent new technology. It's all been done before, so why bother? The Commissioner of the U.S. Patent Office declared in 1899, "Everything that can be invented has been invented." For this reason, he wanted his office closed. "No, no - you can't go farther than you can look, it's no use leaving here."
-- H. Wilker
NASA exists to make the pioneering culture that founded the US have the impression that everything that can be done to open a new frontier for them to escape to _is_ being done. However, what people forget is that central authorities don't _want_ the pioneering culture that founded the US to escape them. It is far more likely that John Carmack will open up the space frontier than it is that NASA will do so.
Seastead this.
The real issue is that many of the private sector solutions to low cost to orbit have either chosen the wrong launch weight, run out of venture capitol, or just not proven to be as affordable and reliable as a NASA launch.
The other thing that needs to be considered about the X33 is that if you can afford to keep it feuled and on the pad, it can be looking down on anywhere on the planet in less than one hour! That's revolutionary.
From the article:
"In the wake of last year's back-to-back Mars mission failures and repeated delays in constructing the space station, a high-profile success would help rehabilitate NASA's tarnished reputation. The X-33 could have produced that success, but for almost a year the space agency has kept the project out of the limelight."
*Nowhere* in the article did they mention the complete *success* of NASA in deploying the ISS. This is hardly a fair reading of the facts.
NASA is attempting to solve hard problems that take time and money to solve and NASA should be given the funding and time to succeed. When completed, this will put our countries space capabilities leaps and bounds ahead of everyone else, and will make projects like LEO comunication constellations finacially feasable.
Tell me what makes you so afraid
Of all those people you say you hate
SSTO systems are, in some ways, extremely simple to evaluate. To get a payload to orbit without staging, you have to have both an extraordinarily efficient engine and a remarkably high mass ratio (fuel:everything-else ratio). It was obvious that the X33 prototype wasn't going to get to orbit very early; the mass ratio just wasn't there; even with rediculously risky materials and structures were specified. So, there were two obvious things to do at that point:
1) Kill the project
2) Lower expectations to a technology demonstrator, and cut way back on the risk.
They, of course, chose the insane third option, maintain the (extremely expensive) exotic materials, but still give up on the the idea of going to orbit. So, they ended up with failed tanks, and nothing to demonstrate whatsoever.
The aerospike engines really are a great idea, it would have been extremely useful to see them fly. As it is, there is absolutely no question that the project will be killed. Lockheed even wants it dead. And why not? They got all the money that they could ever get from the program, and they didn't actually have to produce anything at all.
It's very likely that almost every part of the alleged rocket wouldn't have worked; the tanks were just the first thing to fail spectacularly. The engines had very serious problems too (the ramps that are the key to the aerospike concept were much harder to fabricate and cool than 'expected').
On the other hand, the Delta Clipper, funded by McD primarily; was a system that could be tested in stages, and in that testing they took some actual risks; but measured ones. The first test when they flew the rocket and landed it vertically was a big step -- but they managed the risk to the point where they made it happen. The engines, tanks, and almost everything else in those first tests were off-the-shelf items (the aeroshell was a unique thing, but contracted out to Scaled Composites, a company with a sterling record for this kind of thing.)
So what happens to the Delta Clipper approach. It's killed, of course.
In the end, I have no question that the next-generation launcher will be built by private industry either in the US or more likely overseas. Sad, but that's the way it is.
thad
I love Mondays. On a Monday, anything is possible.