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NASA Eyes Shuttle Replacements
jonerik writes "According to this article at Space.com, NASA yesterday released a status report on the first year of NASA's Space Launch Initiative; the search for a space shuttle replacement, currently planned to begin operating ten years from now. The competing contractors - Boeing, Lockheed Martin, and a team consisting of Northrop Grumman and Orbital Sciences Corp. - have their work cut out for them. NASA is looking for both a ten-fold improvement in per-pound launch costs (from $10,000 per pound to $1,000) and massive improvements in crew survivability."
In related news, Rubyflame writes: "Aviation Now has a
story about four new kerosene-fueled rocket engines being developed by Aerojet, Pratt & Whitney, Rocketdyne, and TRW. These are engines that will produce a million pounds of thrust, intended to outdo Russian designs in reliability and launch cost, and one of them may power a new reusable launch vehicle. Kerosene has the advantage that it's denser than hydrogen, so the fuel tanks can be smaller."
Nasa space shuttle
Takes off like a pile of bricks
Lighter craft required
I sure hope NASA sticks to their guns this time. Shuttle technology is like 30 years old now, and it's seriously *embarassing* because of that. I mean, the gains that they are expecting are reasonable - which shows you how out of date the Shuttle is.
Websurfing done right! StumbleUpon
augment your senses: http://sensebridge.net/
A German concept, AFAIK. Way more reusable than anything NASA has come up with
The days of vertical launches are over.
--- Eat my sig.
This article is light on details but does mention that all of these systems that they are working on are two-staged.
:-)
At first you may think that two-staged launches are a waste of money, but some of it does at least look promising.
The design from Boeing is an interesting one. It looks like a smaller shuttle attached to a jumbo jet. It's then flown near the limits of space where the top ship would then come apart and finish it's journey into space on it's own.
The jumbo jet would then return to the launch site.
I must admit that I would love to see a 1 stage space craft.
Now, I am coming from a background where I am not incredibly familiar with either U.S. capitalism or with issues of defense. Basically, there are a handful of these companies that compete for every government contract. To maintain "competition," the government will try to spread the love around, going with different companies for succesive contracts.
But each individual contract is too big for a single company to fulfill on its own, so whomever ends up winning the contract will turn around and outsource some of the work to...the same "competitors" whose bids they beat out!
As a retired rocketman, I am the first to support expansion and improvement of any nation's space program. I just wanted to point out that the notion of "who will build the next generation shuttle" should be taken with a grain of salt.
"I'm a rocket man / Rocket man burning out his fuse up here alone." - Sir Elton John
Note, there are probably a few naive engineers and rocket scientists.
Funny, I always thought the terms "naive" and "rocket scientists" were antithetical.
I'm generally "Interesting," "Insightful," and even "Funny" here. What the hell happens to me at parties?
"Rockhound: You know we're sitting on four million pounds of fuel, one nuclear weapon and a thing that has 270,000 moving parts built by the lowest bidder. Makes you feel good, doesn't it?"
hehe...
Fore more quotes from that movie go here
My $0.02 will always be worth more than your â0.02, so
Being naive does not make one an idiot. Naivete is the opposite of wisdom, not intelligence.
Lack of eloquence does not denote lack of intelligence, though they often coincide.
With everything that's been going on lately, you might have missed this important piece of 'news'.
Anyway, here's the link.
They just want gobs of money to spend on technology development programs (read "new toys").
American tax dollars are working to make these "new toys". The primary justification for NASA's funding is that the technologies that come out of these "technology development programs" push the cutting edge of modern tech.
It's been a long time since Congress has thought about the values of "exploring space". That's just an side-effect of research spending.
It's like those robot-construction competitions where they have to get all the balls into the goal. The contest isn't to designed to solve the great "yellow ball problem", it's to build and explore ideas in technology.
Congress views funding NASA the same way; by funding NASA they're advancing America's technical know-how. Not to mention that NASA contracts go to high-tech american industries.
There's not some sort of conspiracy to keep regular people out of space here. NASA's just doing its job.
Sweat
It breaks my pluginses, my precious!
Problem was the Saturn 5 was already paid for (million pound thrust kerosene engine -- didn't they call than the F-1?) while the Shuttle that replaced it required billions in development cost. Also, the Saturn could put 4 times the payload in LEO, making it half as expensive as the Shuttle per pound, and it could send stuff to the Moon.
Instead of punching around with the Shuttle in LEO and this Space Station which is the overpriced whatever, we could have kept Apollo going and evolving, and with the same money we have spent, we could have had a permanent human presence on the Moon by now.
What would that gain? Well, we could have a much more thorough evaluation of lunar resources (possible polar ice) and more thoroughly evaluated O'Neil's ideas of using the Moon as a source of construction materials for space-solar beamed power systems in geosynchronous or L-whatever orbits. Instead we are dinking around in LEO learning nothing.
The Big Dumb Booster by the way, was an idea to scale up the Lunar Module descent engine (had to be a KISS design to bring the astronouts down in one piece) -- they gave the job of building a prototype motor to some general construction contractors who didn't know the first thing about rockets, and they test-fired a successful motor. The thing would have been the size of a Saturn but much more cheaply (heavily) build -- payload would have been more in the Shuttle category, but the idea is that boiler and bridge makers could slap them together. Of course the Shuttle killed the idea.
Aside from Challenger?
Please note that during the first 2.5 minutes of every shuttle launch, there are NO abort modes that are survivable. If there are any problems with the SRBs, they cannot be turned off. If there are any catastrophic problems with the ET, it doesn't matter, you must continue your launch profile until the SRBs have stopped.
Three engine shutdown during SRB burn? Shuttle disintegration.
ET rupture? Shuttle disintegration.
Pretty much anything, dead astronauts.
The russians use 40 year old technology, but at least they have survivable aborts throughout the entire flight profile.
Not that I'm an expert by any means but...
I would hope that they start by questioning the need for a shuttle to begin with. Manned orbital flight is pretty well handled with the ISS and the Russians have a cheaper, time proven method of transport to/from ISS that is pretty hard to beat.
As far as repair of orbitals, has that proven to be worth the expense? Maybe it is, especially if they use such a vehicle to do trash collection. Again, I'm no expert but I hope those who are will be considering these things.
It would seem to me that some of the would be costs of new shuttles would be better spent on upgrading the design of Soyez/Progress and making them even more efficient. The rest of the money could be better spent on other projects including unmanned deep space research or manned missions to other planets (assuming those make sense).
. Quit playing Monopoly with Bill. Switch to one of many non-Microsoft products today.
On another article a few weeks back, someone posted an answer that cleared this up for me. (I'm too lazy to track down the posting now.)
Bottom line is: hydrogen is like a high-horsepower, high-RPM turbo racing engine; it's best for driving light vehicles at high speeds (upper stages). Kerosene is like a high-torque diesel truck engine, good for getting a lot of weight moving from a dead stop.
The difference has to do with the physics of exhaust density, speed, momentum, etc.
You also forgot to mention the fact that before every launch, an explosive demolition team arms a large satchel of c4 in the nose of the SRBs. Gee, I'd hate to be the one to press that big red button when the shuttle deviates from its flight plan.
I'd rather you do it wrong, than for me to have to do it at all.
Its true though that all of the designs share some characteristics...one stage to get you off the gorund, one to get you into orbit. Obviously this isn't by accident...the physics of the problem and materials/fuel presently available must dictate this design.
Because we like to torment you. It obviously bothers you.
I also heard that France was working on a shuttle. Portugal has been flying their shuttle for years, though it's not widely publicized. Mexico scrapped their shuttle project in favor of their rail-gun / light-sail combination system with which they've manage to supply migrant workers for the asparagus farming on Venus.
XML causes global warming.
The most expensive stage of any orbital or even suborbital launch is the first 30 miles or so.
At these low altitudes, air resistance is a major factor and, due to the heavy fuel-load still onboard, a great deal of power is required.
Conventional rocket motors suffer from the need to carry their own oxidizer (O2) but if the first stage of flight used air-breathing engines then far less of this heavy fuel element would be required. The result would be a lighter "wet" vehicle that required less power to fly.
This is why NASA and other researchers are spending such huge amounts of money on things such as the SCRAMJET and Pulse Detonation Engines.
Unfortunately it appears that there's still a big gap between laboratory and launchpad as far as these new engine designs are concerned.
Liquid-fueled rocket engines will always be risky and fuel-hungry. The magnitude of improvement in safety and price-performance being sought will probably have to wait until they're perfected.
NASA needs to trim some of it's bureacratic fat.
Case in point:
Both the University of Queensland in Australia and NASA are developing SCRAMJET engines, or Super Sonic Combustion Ramjet. These are capable of doing extreme hypersonic speeds, up to escape velocity.
NASA has spent $500 million on it's program. It has only produced one failed attempt at SCRAMJET flight.
In contrast, spending only $500,000, the UoQ has already produced a successfull SCRAMJET flight.
NASA takes lots of money and doesn't get anything done. They funnel all their money into the worthless shuttle and space station programs. We don't need to spend money to send people into LEO. It's a cold or hot vacuum a few hundred miles out. Whoop-de-shit.
Before NASA worries about the space station, they should buckle down and actually get a spaceplane. Cancel the shuttle program. It's worthless.
When they have a low-cost spaceplane, they can breed all the rats in space they want, and plus a mission to Mars might become feasable.
Here, about 45 years after Sputnik, we still haven't gotten rid of our horribly expensive rockets.
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
I wonder what has become of Lockheed Martin's "Linear Aerospike" engine technology. When X-33 went down the tubes, LA engine tests continued. The results looked somewhat promising.
Commercialization of space could make NASA's life easier. Now, they loathe the idea of having to compete, it would show just how much mismanagement there really is at the organization.
.
However.......one of the single biggest problems with the Space Shuttle is also one that could be solved in the future by creating a market for them - with space tourism or somesuch.
When you decide to build something like the Shuttle or the Concorde and then you find yourself with one or two users and no need for any more beyond the origional production run, then you have serious problems down the line that drive up costs to an insane level.
Simply put, you run out of spare parts.
The Shuttle and the Concorde were built all at once. The factories churned them out one after another. They needed parts - lots of them - so factories mass produced them.
Then, there weren't any more Shuttles to be made, so there was no need for parts to be built.
Time passed.
Things broke down.
And they broke down again.
And again.
Guess what happened? They started to run out of things. But you can't retool an entire factory to make 100 more of something you need - and do this for every part. So, instead, when something breaks, you have to make it. If some parts of the Shutte go bye-bye, guess what? Someone has to walk into a file room, pick up the blueprints and make a one-off of that part by hand.
Sounds like excruciatingly time and money consuming fun, huh?
Well, it _is_
A growing market for a vehicle such as the Shuttle would mean more parts could be built, and for less. A permananet Shuttle maintence industry could be established, driving costs through the basement.
It is hard to tell how much a Shuttle launch costs. The numbers are so embarassingly large that NASA cooks the books to try to make them look better.
Almost all of the costs for the Shuttle are salaries for the huge army of people NASA employs. According to Henry Spencer, the Shuttle program's costs are nearly constant: they stay pretty much the same, no matter how many or few launches happen in a year. (So you might as well launch stuff.)
You are absolutely correct: NASA should have taken the working Apollo designs and incrementally improved them. If they had kept up a good improve/test/fly schedule, we would probably have several cool 2001-ish space stations and a moon base by now. But for whatever reason, NASA developed the Shuttle in a massive paper design exercise, to be a giant leap forward in spacecraft. No need to build X vehicles and test them! Just build the Shuttle, perfect the first time!
Maybe BDB is the answer. Maybe SSTO (single stage to orbit, a completely re-usable spacecraft) is the answer. I don't know. But I do know that NASA is past its useful life, and the answer simply will not come out of NASA.
What the government should do is promise to buy X launches at Y tons of payload per launch, perhaps with special tax credits or other bonuses. Then wait for launch vehicles to appear. The money will never be spent if working vehicles don't appear, and if they do appear they will be cheaper than anything the modern NASA can create.
steveha
lf(1): it's like ls(1) but sorts filenames by extension, tersely
Naivete is the opposite of wisdom, not intelligence.
Only if you equate wisdom with cynicism. Being cynical never got anyone to the stars.
I'm naive, and damn proud of it.
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
If we need real-time human intelligence for planetary exploration, telepresence from orbit is likely also a better choice than human landings: you reduce risks greatly, save on equipment, and still get real-time manipulation. But current planetary exploration goals are so modest that purely robotic systems are probably better.
So, let's scrap human space flight for the time being. We can do an enormous number of really neat exploratory missions in space for the cost of the shuttle program and its replacements. When we return to the issue of human space travel again in a few decades, we'll have much better technologies.
Who says the 'moon base' has to be made out of metal? Why can't you ship up some excavation tools, and light weight polymers and build an airtight underground lunar base with the only imported metal being the airlock doors? True, this doesn't provide you with any method for creating food, but We Could have had a lunar base easily. One much larger than any of the space stations we've shipped up, because as you recall all of those ARE made out of tons and tons of metal. There is also a cumulative advantage, the longer you've been building stuff on the moon, the more resources are at your disposal to build more complex projects... Unlike the space stations which all fall back to earth after a few decades. Depending on how far we push nanotech we may not even need to build factories on the moon, we may just need to send up a few machines that recieve power wirelessly and process raw materials into usable resources.
The moon is a more practical environment to work in, the low G enables a person to remain there signifigantly longer than in the microgravity of space.
The Biosphere projects are partially aiming at researching the viability of building an enclosed, self sustaining habitat on the moon, but even if you build a moon base that requires resupplying like space stations do, it could easily be done for less money as long as you take advantage of the fact that you can always dig a hole use some plastic to make it airtight and cover it with a metal lid. Homsteaders used to build houses out of earth and mud where trees weren't available, so why should we build lunar bases out of 'industrial grade metal' when really the only part that has to be metal is the door.
https://www.gnu.org/philosophy/free-sw.html
Okay, Britian has a long history of telling people what they ought to have built without actually putting very much together themselves. But it still strikes me as the right solution.
Firstly, no, the shuttle's primary mission is to launch stuff into space. If all we wanted to do was "learn stuff," we could do it far more economically using subscale unmanned test vehicles.
Secondly, the shuttle was originally supposed to save money vs. the Saturn V. It doesn't. It is at minimum an order of magnitude more expensive to run than the staged rockets it replaced. Just how expensive is not clear: it depends how much of the cost of its infrastructure you include in the cost of a launch. But the absolute minimum I've seen quoted is 300 million a launch, and that does not include infrastructure at all. Compare it to a cost of 20 million for a commercial flight of a Soviet space capsule, which includes both payments on infrastructure and a profit margin. And, because the shuttle was designed at the command of politicians and beaurocrats, the infrastructure is spread all over the country, to spread out the pork and give work to each of the beaurocrats' petty little domains. Why, for instance, didn't we just build the shuttle factory adjacent to the launch site, and cut out the cost of transporting it across the country? Why weren't the landing fields adjacent to the launch site from day one? Why use expensive and dangerous booster rockets? Why build the booster rockets using completely different technology than the main engines? Because it was a beaurocratic clusterfuck, that's why.
The shuttle was supposed to be reusable, so that it could be turned around quickly and relaunched. Instead, it takes months to refit a shuttle.
The shuttle was supposed to be safer than the systems it replaced. Obviously, Challenger blew up, the Saturn V's did not (the crew of Apollo 1 died in a ground test of the capsule, not the rocket). But also, one has to look at the underlying problem of operational complexity: the shuttle is just too damn complicated. It is a credit to the people involved that it has flown as safely as it has.
There were supposed to be many shuttles, flying every few weeks, which would have made each launch less expensive by spreading out the infrastructure costs more. Instead, there are a handful of shuttles, flying about once a year. They're too expensive to build, and take too much time to refit.
I'm not even going to talk about it landing at airports.
Lastly, when you look at Shuttle, you have to point out that at the time we stopped production of the Saturn V, we HAD THE SATURN V ALREADY. The space shuttle cost billions to develop, on top of what we had already spent to develop the Saturn V. Worse, it set the space program back at least 20 years. Hell, we still don't have a replacemnt for the Saturn V.
Jon Acheson
All opinions expressed herein are my own, and not those of my employers, who are appalled.
Ground based lasers will always be subject to thermal blooming due to atmospheric attenuation.
Interesting. Is this caused by the lasers or just natural artifacts of the atmosphere? Incidentally power is the cheap bit in the equation, and you need less of it delivered at altitude due to g-limiting anyway; so it may not matter.
Atmospheric. You have two effects happening. One is that minute particles in the atmosphere scatter the laser beam. This is unavoidable, and causes exponential attenuation over long distances. The second is that the atmosphere absorbs some of the light you're sending, and heats up. This causes optical mayhem that defocuses the beam.
Compounding the problem is the fact that you'll have to fire through a *lot* of atmosphere. Your craft needs most of its velocity to be tangential, and you want as long an acceleration path as you can get away with to keep the acceleration to something that a) you can provide and b) won't damage your cargo. This means a grazing path through the atmosphere, which means your lasers will be firing through hundreds or possibly thousands of kilometres of air (i.e. as far as you can manage).
The only practical scheme I can think of for very long distances is to have multiple stations along the flight path and to fire a converging beam, so that heating problems are only significant for the last little part of the beam path.
On a couple of other points: You'll be using a laser array, not a single laser, so the cost will be directly proportional to the power required. More power means more cost.
Also, I have doubts about a heat-exchanger system working. Throughput tends to be low compared to the power flow required to get high ISP, and a heat exchanger means a heavier craft. The most practical craft design I've seen suggested, which has flown in small-scale tests, has the bottom of the craft being a curved mirror with a central projection. The laser is focused by the mirror and heats air immediately below the central projection, which is shaped to force the air to move away from the craft.
Laser launchers are a neat idea, and avoid the problem of carrying most of your reaction mass when set up in jet mode, but there are formidable engineering problems to overcome before they're practical.