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NASA Scraps Shuttle And Returns to Rockets
nathanh writes "NASA is building a launch system that they've informally dubbed Apollo On Steroids. It's a hybrid design of the Apollo capsules and the Shuttle's booster rockets and engines. Crew and cargo are lifted by two different rockets: the crew use a single-booster/single-engine rocket and the cargo is lifted by an awe-inspiring two-booster/five-engine rocket. NASA reckons this craft will take humanity back to the Moon and then to Mars. Has NASA realised that the old designs were better? Or is this all a ploy to recapture the hearts of the public?"
Does anybody remember the concept of the next generation space shuttle that nasa talked about during the mid to late 90's. I remember there was research and products being developed for this project. Does it still exist, or has it just vanished into the black hole of failed/forgotten nasa projects?
Accelerate at (-)1g for the entire trip?
That is a phenominal waste of fuel... bloody ridiculous.
If/when we get working fusion + ion drives or something then it might be feasible, but with conventional rockets this is out of the question.
Umm...NASA's budget has actually increased with respect to inflation for the first time in recent memory.
Or you could do something rather like Mars Direct and just spin the who vehical, with a tether to the last stage of the launch system...
The shuttle was never build for lunar travel. It is important to understand that different spaceships are used for different tasks. The shuttle is used to bring cargo up to (low) altitude, while escaping the earth gravity completely and going to the moon (or mars) is a completely different story.
You might carry a Luna space ship into orbit with the shuttle, but then you will just be carrying a spaceship within a spaceship. That would be a waste of fuel.
The shuttle is only good if you wish to bring stuff back down with you. In that regard you might have used it on returning to the earth. The returning spaceship could dock with the space station and transfer men and cargo to the shuttle for safe landing. But that's only saves the weight of a single heat shield.
So dropping the shuttle for a Luna and mars mission is the obvious choice. A lot of comments will be made in regard to "return to the old capsules". But this is not really relevant. The "old" capsules were a good design. The engineers for the first Luna expedition did a lot of thinking and testing before going there, so it's a good design. To come up with something new, just for the case of "making something new" would be stupid.
But these new capsules are not old! They use a new propellant, to prepare them for the mars expedition. And as the old Luna Lander had computer power equivalent to a modern average car, I'll expect the new ones will be far more advanced.
This is the same case in regards to the boosters. These are actually based on the Shuttle engines and lifters. So the engines are the same, even thou the exterior is not. And these boosters are far more advanced than the old ones as well.
So scraping the Shuttle and returning to the old capsules?
Not true.
-:) Oh no - not again.
www.rednebula.com
As much as I'd like to think "ploy", they probably are onto something.
If you think about automobiles, for instance, the most efficient configuration seems to be a combination of small passenger cars and large semi-trucks. The shuttle was basically an SUV: high maintenance, high cost, low gas mileage and range, and not big enough for truly heavy lifting. It was popular because it fit into the American one-size-fits-all independent mentality.
But the shuttle was also part of a natural evolution. We started out driving a Pinto. We had newfound freedom, but little useful to do with it. To take the next step required a vehicle capable of doing some serious work. But we couldn't afford to go from a Pinto to a Mack Truck. That would've been too expensive, and risky. Instead, we got a Suburban, and used it as a daily-driver, as well as for some backyard projects. The insurance was less than having two autos. There was some maintenance, but we could do it ourselves, without an expensive mechanic.
Now, though, we can afford both the Mercedes and the F-350 flatbed. We have a legitimate use for each. Eventually, we may need the equivalent of a subway car, and a Greyhound bus, and a bullet train. But even here on Earth we have lots of different ways to get around, each optimized for a specific task. We shouldn't be surprised that space is no different.
"I assumed blithely that there were no elves out there in the darkness"
Or they could exercise on the way over there with resistance equipment (like big rubber bands or springs).
dnuof eruc rof aixelsid
Russian engines have had greater lifting power for many years, and Russian-developed RD-180 (around 4000kN) engines are made by Pratt & Whitney for Atlas V launches. Compare this to the SSME (Space Shuttle Main Engine) at about 2000kN, and it makes me curious why they don't opt for a proven, heavy-lifting engine like the RD-180 (at least for the cargo lifter).
9.8 m/s^2 or so.
Private companies like Lockheed-Martin or Boeing? Yeah, The Atlas V and Delta 4 cheaper, but not by *that* much. The cheapest boosters are quasi-government (Russian, specifically. Although the Ukranian Zenits shouldn't be all that expensive). And rather good (The Soyuz booster is perhaps the most reliable on the planet). There's also a reason why Zenits and Atlas IIIs and Vs use Energia derived hardware. As far as fuel efficency goes, SSMEs are some of the best (chemical) engines out there.
It can be done much simpler: split the spacecraft in two and connect them with a long steel cable. That way the two halves can rotate around their center of mass and create artificial gravity without the trouble of getting a huge construction into space. Also it is easier to make a large diameter for which a low angular velocity will be sufficient to create 1 g, thus reducing disturbing Coriolis forces.
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You Sir, are a moron.
2 fatal accidents per 114 launches is a failure rate of 1.7%, not 0.017%.
And if your bike a fatal accident rate that high you would probably have died in your first week or two of full-time riding.
Seriously, every one of the comments above did not mention it. The Space Shuttle is the ONLY way to lift the new sections and the only way for America to send/get back astronauts (Though we can hitch a ride with the russians like we already have)
There is a gap between where the Space Shuttle will be retired (if it isnt taken out of service or has another catastrophic failure before that) and when the new CEV and Heavy Lifting vehicles hopefully come online.
There are 15-20 trips required of the Space Shuttle just to finish the ISS, can it make all these trips before 2010 when it has to be recertified and will probably be decommisioned altogether?
What will be done in the 4 year gap to 2014 when the new vehicles are due?
There is truth in humor.
The Moon is a Harsh Mistress
"Source... The Final Frontier" -- keepersoflists.org
Well, they are polluters, but I suspect that even if we moved to 1 a day, that we would not make too big an impact.
As too expensive, that is not accurate. The solid fuel is slightly more expensive than liquid O2/H2 systems. However, it does not require the cost infrastructure that does liquid systems. In addition, this is being used primarily to launch crew, not cargo (I suspect that the airforce will probably keep a few hanging around to launch spy sats. on a moments notice). When it comes to life, we should be (and are) willing to spend a bit more to get a better saftey record.
Now as to fragile, it is one of the most stable since it can not blow up. Now, I am sure that somebody is going to mention challenger. The solid booster did NOT blow up. It was the main liquid tank that did due to the O-ring leaking a plume into it. if we had this system in place, the leakage would have meant that those 2 segments would have had a hole and they would have been unuseable. If the hole actually got big enough, it would have meant that the capsule would have been jetisoned for crew ecscape, and everbody lives. This would have been a fraction of the costs of the challenger/columbia incidents.
At this point, the solid units are one of the best approachs at getting man into space, quickly. Long term, we will almost certainly change. In fact, I am in hopes that t/space will be a big winner.
I prefer the "u" in honour as it seems to be missing these days.
It's not really news at all - I mean the European Space Agency has understood the value of Russian engineering done decades ago and simply decided that it was the better choice over spending vast sums of money on try-and-fail schemes. Even more interesting is: "In 2007 a Soyuz launcher will take off from Europe's Spaceport in French Guiana (South America). This will be an historic event as it will be the first time that a Soyuz launcher lifts off from a spaceport other than Baikonur or Plesetsk. It will also be a milestone in the strategic cooperation between Europe and Russia in the launcher's sector."
I've got a buddy who works at in the space division at Boeing - when I asked him how come we don't just use Apollo tech to get back into space, he gave me a fairly interesting history lesson. All the data for the space programs of the 50's, 60's, and 70's was systematically destroyed while the programs were current. They didn't want any plans to leak, so every two months all the paperwork was destroyed.
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This is an old myth. It's not true. See
http://www.space.com/news/spacehistory/saturn_fiv
And how do we know they didn't try progressively larger stone buildings?
What is know from documentation (Egyptians did write, and tho not everythign has been preserved, they did also write about their technology and history) as well as found evidence is that pyramids were not the first substantial stone structures they built, and they did not start out building the big pyramid from scratch.
There are examples of failed pyramids, and there is very good reason to believe that first of all, the attempted as well as the finished pyramids were substantially bigger then anything built before them (and actually, only in recent times humans built anything that would match them in size), and were pushing the limits of building technology at the time (they would have done that untill about 150-200 years ago and maybe even more recently).
So, while they did not start building them without any previous experience in stone building in general, the known number of failures, documentation and archeological evidence seem to suggest that pyramids were pretty much developed with trial and error, over a relatively short time (a few generations), and by attempting to build soemthing way beyond the known possibilities of technology at the time.
I've worked at NASA JSC since 1979. There was a history archive building (or actually, several). I worked in one of them on a very slow second shift, watching data reduction programs design the leading edge of the shuttle wing, among other things. I browsed the library for reading material while I waited for tapes to spin and printers to print. (And card readers to read, too!)
All the plans were there. When they shut down the office, they dumped boxes and boxes of duplicate records, books, etc, that had been collected as the various parts of Apollo, Apollo-Soyuz, Skylab, etc shutdown. I got a chronology of Skylab. Another coworker got books on Apollo and Gemini, along with drafts of the first space shuttle - the one called Dynasoar, and its descendents, from back in the 1950's.
"Systematic destruction" is complete baloney.
Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.
nuclear propulsion is politically off-limits
Hopefully not for too much longer. According to recent polls Americans are less likely to agree with or pay attention to environmental groups than at any other time since the '60's, and many who previously would've opposed the construction of nuclear power plants are now in favor of using them to replace current oil and coal-fired plants. The trend is especially marked with the under-40 age group, who describes itself as "disenchanted" and "increasingly skeptical" of environmentalist claims.
With the primary political base of environmentalism shrinking due to the aging of its main supporters, it's quite possible that nuclear power - once the Great Boogeyman of our hippy past - will make a strong resurgance. And with that comes the possibility of using it for other applications (international treaties to the contrary be damned).
Max
My god carries a hammer. Your god died nailed to a tree. Any questions?
The idea of a tether system has yet to be successfully demonstrated.
.3G for Mars local G to 1G for the return home.
I'm personally in favor of them utilizing some wasted external tanks to create a sort of octagon around a central propulsion tower that could be spun for anywhere from the
The biggest problem foreseen with any rotation scheme is of course the coriolis forces whereby your head experiences an amount of gravity fractionally different than your feet. This gives new meaning to the term light headed.
"There are no facts, only interpretations." --Friedrich Nietzsche.
Now as to fragile, it is one of the most stable since it can not blow up. Now, I am sure that somebody is going to mention challenger. The solid booster did NOT blow up. It was the main liquid tank that did due to the O-ring leaking a plume into it
Great point. If anyone cares to remember the soild boosters kept going after the main tank exploded.. Ground control had to blow them up since they were now uncontroled. Now that's stable!
If you think it's expensive to hire a professional to do the job, wait until you hire an amateur. --Red Adair
For buildings and things like that you are completely right, since they have to withstand compressive forces (gravity) and the lever effect of forces that try to bend the structure. However, with the space module with counterweight one only needs to have tensile strength. If the space module has a mass of 10 ton and you wish to create 1 g, you only need a steel cable that can handle 10 tons of weight (at 200 kgf/mm2 that is just 50 mm^2 cross-section, plus a safety margin, so say 1 square cm). A 200 m cable would weigh about 160 kg, i.e. much less than the space module.
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Not the Army, but the Air Force, and really the NRO, whom the Air Force is working for in the spysat biz.
Second, they never did it. The Vandenberg site was a boondoggle and work on the Shuttle facility was scrapped after Challenger. I was living in L.A. in the early 80s and REALLY looking forward to shuttle flights out of Vandenberg. SLIC-6 at Vandenberg is now an ELV facility, and the Air Force has EELV, which handles their requirements.
Agree, however, that the shuttle was trying to please too many people in order to get funded. That, and they jumped from drawing board to operational fleet of 5 orbiters without a true demonstrator or X-rocket. The Shuttle Main Engine is an impressive technical achievement, but is costly to reuse. The original vision of routine spaceflight at $100/kg was never remotely achieved.
Helium balloons want to be free.
They also have seperated the people from the cargo so the people ship can be more reliable, and the cargo ship can be less reliable, e.g. the solid fuel boosters.
Strapping solid fuel boosters to people has never been a good idea.
Inside every complex program is a simple solution trying to get out.
"For starters, now for anything smaller (e.g., a 1-2 ton satellite)..."
First of all, it's the Air Force, not the Army. Second, no one's putting little tiny satellites on the Shuttle. You've got Pegasus, Minotaur, Athena, and soon Falcon boosters for small payloads, for example. And there most certainly IS a need for heavy-lift capability. After the Challenger disaster in '86, the Air Force was left without a booster for those heavy, polar-orbiting satellites and had to upgrade the Titan boosters to fill in. The last of those launched last week.
I'll agree that the Shuttle is a waste for most payload delivery tasks. But keep in mind that the heavy payload launched last week (undoubtedly a very expensive spy satellite) is DISPOSABLE, because we have no capability to get to it and upgrade or repair even the smallest thing on it. In theory, manned access to those orbits could have given the military more bang for the buck.
I'm replying to you, but all those proposing 1G acceleration need to listen. 1G acceleration for 24 straight hours as proposed by the 1/2 trip then flip idea is approximately 6000 mach or 1,894,058.7 mph. Assuming perfect utilization of energy it would take 358,467,379,200 Joules of energy per kilogram of weight. This means that it would take 4 MegaWatts of constant power per kilogram of weight sent in this mannor. For an average person it would be in the neighborhood of 200 to 300 MegaWatts. Figuring in a return trip your talking about 384 MegaWatt hours per kilogram. Now we also need to account for the ship, crew and supplies. The "new" nasa ship weights 25 tons or 25,000 kg which makes our power needed 100 GigaWatts of power that can be sustained for 96 hours of operation. Get a clue people the power requirements are beyond what we can hope of at this time.