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Next NASA Vehicles To Resemble Shuttles
ausoleil writes "Spaceref.com has an internal NASA memo outlining potential plans for the next generation of launch vehicles. They will closely resemble the current Shuttle and use some of the same hardware. Of course, they plan to leave the exploding parts out of their next versions. From the article: 'NASA has decided to build two new launch systems - both of which will draw upon existing Space Shuttle hardware. One vehicle will be a cargo-only heavy lifter, the other will be used to launch the Crew Exploration Vehicle.'"
This memo could be a photocopy of something circulating thirty years ago. Sounds like they're finally going to take advantage of the modular parts of the shuttle the way they talked about when the shuttle stack design was being originally being funded twenty-five to thirty years ago. One nice change is that the rumor mill believes the heavy lift stack bears a striking resemblance to Robert Zubrin's Ares stack (a.k.a. Shuttle-Z).
The "Shuttle-C" cargo stack (and variations) were originally publically discussed in the early '80s as reasons why the shuttle was worth all we were spending (you don't just get the shuttle, you also get a "normal" heavy-lift launcher). Those variants, however, have had problems that could only be resolved by massive cultural change at the NASA level. One of the biggest issues was payload capacity of the side-slung configuration. Since then variations including the Ares stack and the more recent Shuttle-B have appeared and pretty much gone nowhere.
I suspect that the United Space Alliance's (USA's) "risk averse" culture will actively hinder and ultimately frustrate all of these plans. If you've ever worked for a government contractor, you'll understand the culture I'm talking about. They (Boeing and Lockheed-Martin, the companies in the USA partnership) don't have to compete in markets, and are positively allergic to any hint that they may have to compete with other companies for revenue. If NASA's hoping for bargains, they won't find them when dealing with USA.
Regards,
Ross
To obscure that fact that we are going back to a model used back during Apollo. After all this waste, we go back to non reusable heavy lifting and deorbiting like a stone.
So, as always, (good science/actual military need/sensible budget-keeping (pick appropriate phrase based on article) ) takes a backseat to Senator Whosit saying, "You won't cost my state jobs!"
Have you been touched by his noodly appendage?
Overall, not a bad idea--it will be a Saturn V class booster. I am not crazy about using 6 SSMEs however, they are designed to be reusable, not flown on an expendable booster and are expensive as hell (about $300 million for the 6 first stage engines alone) Also, I seems to only speak of using 2 SRBs in the in-line HLLV, it would seem to me to make more sense to use 4 or 6 clustered around the core. After all, the shuttle SRBs are some of the cheapest power you can get.
Take the case of SkyLab vs. the International Space Station. According to Wikipedia, the two stack up as follows:Now with some simple math, we find that SkyLab averaged 77,088 kg per launch which the ISS averages about 8,380 kg per launch.
If you didn't just do a double take, you should have. The booster that lifted SkyLab stuck over 9 times the mass into orbit that current ISS flights do! Just what is going on here?
The answer lies in the Saturn V Booster vs. the current Space Shuttle. A three stage Saturn V had a maximum payload of 118,000 kg. (That's enough to send the entire ISS up in only 4 flights.) The Space Shuttle, OTOH, only has a cargo of 28,800 kg to LEO. So why does NASA want to reuse the tech? Because of the weight of the shuttle itself.
The Space Shuttle orbiter weighs in at a whopping 104,000 kg! Combined with its cargo capacity, the Space Shuttle is capable of 132,800 kg to LEO! That's way more than the Saturn V could manage on all three stages. So if we ditch the orbiter itself, the shuttle's infrastructure could be the most powerful superbooster ever designed.
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The escape hatch also has exploding bolts.
The only exploding part that should be left off is the leaky o-rings that helped the chalenger to exploded in '86.
now if we'd stop spending our money exploding things in the middle east, where could have these new luanch vehicles sooner rather than later.
sorry 'bout the mess...
trying to exercise his constitutional right to never, ever be offended.
Have you been touched by his noodly appendage?
Both the single-stick CEV launcher and inline Shuttle-derived HLV are good, useful rocket designs. They have hardware heritage, long experience and the SRBs are one of the safest (if roughest) rockets around.
The only problem is that this continues the massive NASA workforce, which is going to limit the actual implementation of said designs. The standing army needs to be repurposed instead of played to - shutting down the OPF isn't enough. These are massively labor intensive rockets they are creating - they may create as many problems as they solve.
The Shuttle has got to go, I'm glad Dr. Griffin is taking this step.
Josh
gigantino.tv - Heavy but weighs nothing.
It's nice to know that NASA is putting together two new launch vehicles for cargo and crew. However, what's on the drawing board to follow those vehicles in the next 10, 20, or 50 years from now? Or, is NASA is doomed to repeat the shuttle experience again by using the new vehicles for the next 30 years without having anything new in the pipeline?
What we need is NASA to get out of the vehicle design business and let the free-market industry come up with innovative designs to build, test and deliver. It should be like building cars when the designs keep getting better and more reliable every year.
Seriously. Why are we still building giant fireworks? Couldn't a mass-driver work with new heat-resistant materials? Or those JP Aerospace guys with the blimps-to-orbit plan?
Even the Space Elevator doesn't have this problem. Surely there are better things to do with the money to lower cost-to-orbit than building giant bottle-rockets. As long as we remain under the paradigm of taking our fuel with us, it seems to me the cost and complexity goes through the roof. My two cents only.
NASA Budget Shows Shuttle Phase-Out
Erm, actually they are keeping the "exploding bits" and leaving out the bits that so far haven't exploded. The SDV will include the solid rockets (which doomed Challenger) and the fuel tank (which doomed Columbia). The only bit they are leaving out is the orbiter, which has so far has worked properly.
Having said that, it is still an extremely good design. It's almost exactly what the Soviet Union built (separate Energia heavy lift and Soyuz crew vehicles). The only difference is the use of solid motors (which explains why the stock price of Thiokol's parent company has been going up like a, erm, rocket).
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The solid boosters ignition starts with a small Nasa Standard Initiator (NSI) http://www.hstc.com/pdf/nsi.pdf.
That then ignites a small pellet of boron / potassium nitrate.
Which ignites a small rocket motor which is about 4 inches long.
Which ignites a medium sized rocket motor about three feet long.
Which fires a jet of flame for about a tenth of a second, all the way down the whole inside length of the solid boosters, which ignites the whole inside at the same time.
Well, I've been trying to submit a story to slashdot over the past few days about a "parallel path" to government-built shuttle-derived that NASA recently announced, but I haven't had any luck. I've already had four or five variations on it rejected. Anybody have ideas on what might be wrong with the following submission?
At a recent talk, Michael Griffin outlined NASA's plans for helping to generate a robust and competitive commercial market in orbital spaceflight. The speech and Q&A transcripts from the talk are available. In a move reminiscent of the US government kickstarting the early airline industry by purchasing airmail services, NASA plans on supplementing government-derived transport by purchasing cargo delivery services to the International Space Station from commercial providers, followed by crew transportation after the systems have proven themselves. Unlike traditional government contracts, sellers wouldn't see a profit before the services are delivered and the emphasis will be on actual performance instead of process and specifications. Aviation Week has some commentary on the announcement.
On the one hand, I'm glad. The Shuttle has proved to be a horrible waste of money, a boondoggle of 1970s technology dictated by political pork and military paranoia rather than being designed for an actual specific purpose, and I'm glad it's going to be replaced.
It's just a shame that the only way we can get people out into space seems to be with 1960s technology rather than 2000s. At least, under the current government-funded model.
You must think in Russian.
relax, comedy is some peoples way of dealing with terrible events, ever heard the phrase i didn't know wether to laugh or cry, now you know
"Should concentrate on smaller devices. I can imagine a robot same size as a Radio Shaft "Zip Sap" moving quickly to space"
Space is still way the heck up there, and you still need lots and lots of fuel and oxydizer to get up to LEO. You don't see stuff the size of sounding rockets getting up there.
Besides, the bigger the pieces we can send up there, the less on-site (i. e. on-orbit) assembly is needed when it gets there. Even for us on the ground there is a lot to be said about pre-fabrication.
The vehicles being proposed do not at all resemble the shuttle. The shuttle itself is being scrapped. The solid rocket boosters, a modified external tank, and the Space Shuttle Main Engines (SSME's)
The key difference between the new models and the existing shuttle is serial architecture versus parallel architecture. The Space Shuttle is an example of parallel architecture - all of the stages firing together. The new proposals operate in serial, one stage at a time. That's a lot safer: abort modes are easier to implement. A first stage failure is not immediately a fatal incident. Also notice they are implementing the CEV for the crew module, not a shuttle.
And although the spaceref article and pretty pictures are new, the ideas/rumors have been floating around the Aerospace community for quite some time now.
-everphilski-
detla-V = g*Isp*ln(m1/m0)
... hard. And this doesn't include mass requirements for coming home: retro-rockets, wings and landing gear or parachutes and more rockets, etc.
where:
delta-V = 7600 m/s for LEO (a little more for space station)
g = 9.8 m/s^2 (gravity)
Isp = 295-450 1/s (Specific Impulse, basically a thrust rating of a propellant. 295 for a solid in a vacuum, 450 for a SSME in a vacuum. Lower on the surface of the earth)
m0 = takeoff mass
m1 = mass on orbit
Play around with the numbers. You will find out quickly that single stage to orbit with any significant amount of payload is
Until some material advances are made (mass ratio, m1/m0 can be imrpoved) or nuclear propulsion can be considered an acceptable option (The technology exists: Isp = 800-900) single stage to orbit with any more than 1-3 human beings will be a difficult feat.
Staging alleviates the problem. Check out Sutton's Rocket Propulsion Elements or Hill & Peterson's Mechanics and Thermodynamics of Propulsion.
Re-using existing technology is the quickest, cheapest, easiest way to get back in business. I think it's a pretty good idea.
IAAAE (I am an Aerospace Engineer)
-everphilski-
It would be great to be able to put up 100-to-1000 kg payloads in LEO, inexpensively, reliably, frequently. The space science community would be overjoyed, but they would not use the ability to assemble big things from little things.
Suppose that the way you got a new automobile was by having it mailed to you in 50 pound packages. It is probably possible to get cars this way, but the cars would be very different from the cars we have now --- heavier, slower, less fuel efficient, leaving a rather larger trail of (packaging) debris, and a few specialized tools, that would be useful for nothing else. Such cars would probably have no welds for assembly, and manufacturing techniques which required hazardous chemicals or heat processing would simply not be available. The lesser performance would arise from the "design for assembly" which is rather different from "design for manufacturability." (If the 50 pound limit was enforced, there would be no monolithic engine blocks; this would probably imply the existence of many small engines coupled together with a complex, heavier, transmission.)
The upshot here is that, from the point of view of weight, energy efficiency, complexity reduction, maintainability, testability, there is practically no sense in which it would be advantageous to create a big thing by launching little things for remote assembly, unless it becomes far cheaper (cost per kilogram) to launch little things than big things.
You're leaving out the fact that a portion of the engine is built into the orbiter. I'm not sure exactly what it masses, but I'd take a guess it's bigger than the difference between 118,000 kg and 132,800 kg.
On a totally unrelated note, why don't we use the rest of the metric scale when dealing with really big stuff?
Have you been touched by his noodly appendage?
Please, have a little respect. The "exploding parts" comment in the headline was uncalled for and childish.
Ok, so I'm probably not the only one here who's dissapointed in finding that NASAs next big plan looks and sounds really BORING. But if we're really serious about space exploration, then what's most important is what it can do to further that progress, not how it does it. Now, my big gripe is that "progress" itself doesn't seem all that important in this design as Congress keeps whining about space program employment and timeline crunches, but if this is the quickest and cheapest way to improve the space program, I'm all for it. It'll be the plan that probably gets humans to mars, after all... probably late in it's lifetime (probably no sooner than 2025, I forget the timeline).
But strangely enough, it looks like R&D for new space technologies is on the backburner at NASA to fund the actual program, while new private enterprises such as SpaceShipOne and LiftPort research and develop contemporary technologies that can achieve things like reusable, horizontal takeoff space planes and the space elevators. Problem is, the last 30 years have seemed to be fairly unproductive in terms of designing new space transportation oriented technologies. There have been numerous "space plane" projects, yet none of them have been able to produce a viable plan that is both doable and cost-effective. So, it's no wonder that NASAs cheepest solution is to basically make a new plan that simply reuses older technologies. That said, with the new companies mentioned, as well as many more in their early stages, this next generation of space transportation will see a much higher amount of R&D. Come 2040 (or whenever the new space shuttle fleet retires), there will be much more new space transportation technologies for NASA to steel. Until then, it looks like sexy spacecraft are more destined for private enterprise.
BTW: reading up on the concept of a "Space Elevator", the implications of such an installation are immense. I'm picturing a private enterprise like LiftPort completing one by 2020. Suddenly NASA turns around and realizes that they can completely skip earth to orbit spacecraft and scrap their current fleet to create space-specific craft which are more fuel efficiant than airplanes. Whoops! Leave the bottle rockets to kids.
Multiplayer Gaming (defined): Sitting around, discussing single-player games with my friends, at the bar.
... all of our old mistakes.
Horrible, horrible idea. They're taking two of the three worst components of the current shuttle platform and reusing them in a system where we have already made and used much better systems. The only way they could make it worse is to rely on the current shuttle thermal tiling.
So, lets look at the other two pieces. SRBs? They killed Challenger. They've never worked properly, or we wouldn't have been getting blow-by as routine. If NASA is insisting on sticking with solid fuels, for whatever odd reason, they need to make them non-segmented (although there are other practical problems here that would have to be solved). Increasing the segments to five is just going to make the problem much worse, since the joints are the weakest part of the system, which means more losses.
Then we've got the SSMEs. Good ISP, fine, but the mechanical problems are still around. We've never, ever been able to get these to work the way we wanted them to. NASA just keeps moving the "acceptable" bar every time a new problem is found. They need a complete redesign to get rid of the problems we do know about (that's what top-down design gets you), but that'd be far too expensive. If we want to stick with old tech, we'd be much better off just remaking the tools for the Saturn V engines and restarting production.
If this memo at all reflects NASAs future actions, then they'll have proven themselves irrelevant. Unles the US government decides to try out a bounty system, and offers appropriate (ie. billions) numbers for good systems, we're out of the race. Maybe someone else will be able to keep going.
Alita
"Cutting the space budget really restores my faith in humanity. It eliminates dreams, goals, and ideals and lets us get straight to the business of hate, debauchery, and self-annihilation."
-- Johnny Hart
The original shuttle design was going to have the shuttle itself only used for lighter payloads, with the HLLV doing the, well, heavy lifting. There was also going to be a permanently orbiting vessel for inter-orbit transfers, using something like an ion drive... basically, the original shuttle design was going to be lighter and more reliable and just one member of a fleet of specialised vehicles. Congress wouldn't pay for all of them so NASA scaled up the Orbiter and it ended p costing more and doing less than originally planned.
Man, I hope they let NASA do it right this time. If they reduce the weight of the new shuttle so the SSME don't need to run over redline just to do their jobs, maybe they won't have to rebuild it after every flight like it was some damn MIG engine... and if the HLLV doesn't need to be man-rated they can use a less expensive version of the SSME in it and save even more.
You really are nuts. Blatant and covert interference? Replace the Shuttle in two years with half the annual budget?
Okay I should not bother since you are clearly insane but I am bored.
1. Rutan's propulsion system has a MUCH lower specific impulse than the shuttle. A hybrid rocket that could reach orbit would be HUGE. And a single SSTO using the propulsion system that Rutan built would be impossible.
2. Just to build and test man rated spacecraft would take more than two years! Just to write and test the flight control software would take that long. You can not build a modern biz jet from the ground up in two years. So the idea that Rutan could make a shuttle replacement in two years is clearly impossible.
3. The White Knight/Spaceship one could not scale up to launch 33,000 lbs to orbit. Which is what the shuttle is capable of.
Rutan did a great job with Spaceship one. I would bet you a BIG pile of cash the even he would not claim that he could build a space craft that could carry 33,000 to low earth orbit in two years.
Final blatant and covert interference? NASA is using the White Knight as a drop vehicle right now? Rutan has done a lot of projects for NASA including the scissor wing AD-1! Odds are he got help not interference from NASA.
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Over 100 of those was due to a single incident in 1960 which was actually an ICBM test, not a general-purpose space mission. Under extreme pressure from the top government ranks to keep the cold war test on schedule, safety regulations were ignored while frantic launch preparations were made on a fully fueled missile. Somebody accidentally made an electrical connection that ignited the second stage, which engulfed the ground crew in fire.
That singular incident really doesn't have much to do with the current statistical safety of manned space flight.
Not all of NASA's upcoming launch vehicles will look like the shuttle. The X-4000 Launch Aparatus will resemble a giant catapult.
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I haven't checked this out, but a Usenet poster said the original Shuttle frames were going to be built out of titanium, of course for its great strength-to-weight ratio. There was a decision to switch to aluminum, supposedly both as a cost savings on the Shuttle manufacturing, and because there was great demand for titanium in building US Military aircraft. Due to the extra weight of a same-strength frame made of aluminum, two solid-rocket boosters needed to be added to the launch vehicle which were not a part of the titanium design.
Is this true?
Regardless, it seems clear that any launch hardware intended for reuse should be made of the best strength-to-weight materials available even at larger initial cost, so either there's less energy (the fuel itself is rather cheap, but less of it means smaller launch vehicles, fewer complications, fewer SRB's, etc.) required to launch, or a larger payload could be put into orbit with the same launch energy because of the lighter hardware.
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