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Design of Next-Gen NASA Rocket Showing Flaws
caffiend666 writes "According to an AP news article, NASA engineers are concerned about the design for the new rocket meant to replace the shuttle. Work on the project has revealed that the first few minutes of flight could see 'violent shaking', a serious flaw that might destroy the craft soon after launch. 'NASA officials hope to have a plan for fixing the design as early as March, and they do not expect it to delay the goal of returning astronauts to the moon by 2020. The shaking problem, which is common to solid rocket boosters, involves pulses of added acceleration caused by gas vortices in the rocket similar to the wake that develops behind a fast-moving boat.'
How is it that astronauts managed to land on the moon in 1969 but the next mission to get people to the moon will take until 2020? With today's engineering tech...
Basically they spent more in the 60's relative to today's budget to speed up the process. We're taking a slower, cheaper route this time.
Table-ized A.I.
Brilliant! I mean we have more computers nowadays! Computers everywhere means easier everything! That's some solid logic! Never mind the political atmosphere, what with its shoe string budgets and extreme shifts in public opinion. Never mind that there is no immediate, short term goal to be accomplished by expanding space travel. The fact that people haven't been truly interested in the long term benefits or concerned at all, really, with space exploration is completely irrelevant when compared to the amount of stuff we have today. I mean look at them!! THEY ARE COMPUTERS!! THEY FIX EVERYTHING MAGICALLY!!!
At first I thought you were just being a jerk, but then the you dropped the moon landing hoax line at the end. That's when I knew you had it going on! Right on bro! Keeping your ambivalence up in the face of overwhelming fact... that's where it's at!
I got a catholic block.
This was brought up last NASA story. Somebody pointed out that just ONE of the technologies produced for the Hubble telescope lead to more money saved on machines scanning for breast cancer than it cost for the Hubble in its entirety, and that's just the price tag, not the lives that have been saved because of that alone.
When stationary, the air must have a net velocity in excess of 400 mph for the engine to retain efficiency - which a turbine can easily do if there are no other complications. Eventually, the turbine gets in the way, hence the need for a really good bypass system. White Knight avoided the need for TAR by having the first stage as an actual aircraft, but a conventional aircraft isn't going to be capable of carrying the weight needed for true orbital flight, let alone interplanetary flight. Affordable space flight is probably going to require TAR engines.
(Other alternative launch-assist methods include using linear accelerators - basically strap the rocket onto something akin to a bullet train and then get the train up to the critical speed, or using a very powerful gas cannon to fire the rocket into the air at the critical speed. The first would likely end up more expensive to operate than a TAR, the latter would require a very sophisticated multi-charge arrangement if it is to avoid killing everyone onboard, but might end up being another viable method.)
One thing I think can be said for certain - by 2020, no sane engineer will be designing launch vehicles for space that use a rocket first stage. I'll give it a 40/60 chance that by 2020 commercial space flight will have surpassed NASA in terms of cost-per-unit-mass-launched, and 20/80 that hobbyist space flight will have done likewise. If NASA persists in long-outmoded next-gen launch vehicles, then somewhere in the 2030-2050 timeline, NASA will be redundant. Government-run organizations make sense for bleeding-edge work because that is generally too expensive for everyone else. However, once everyone passes said Government agency's technology, it has no value or merit. To have value for money, NASA should be working on systems that will become bleeding-edge in 2020, not what were bleeding-edge in 1920. R&D is the expensive work, everything else is meccano tech.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Interesting article. It was written just after the Apollo 6 unmanned test of the Saturn V in 1968.
The mission went quite poorly. 2 engines failed on the second stage, and the third stage engine failed to restart in orbit. Parts fell off the shroud, too.
Still, NASA went ahead and launched the next Saturn V with a crew to the moon (Apollo 8). Another unmanned test was not performed to "save about $280 million and avoid further delays in its program to place U.S. astronauts on the moon in 1969". This has often been called the greatest risk ever taken in the space program, and was motivated by reports that the Soviet Union was preparing for a manned moon flyby. It's a totally different risk matrix than what governs NASA today.
Worst...sig...ever!
""I hope no one was so ill-informed as to believe that we would be able to develop a system to replace the shuttle without facing any challenges in doing so," NASA administrator Michael Griffin said in a statement to The Associated Press."
Well, duh, the whole point of the 'shuttle-derived' Stick design was that it was supposed to be safe to fly and fast and cheap to develop because the shuttle technology would avoid these kind of 'challenges'.
But instead of building a capsule that could fly on the shuttle-derived launcher they've expanded it into an orbital RV which requires major changes to the launcher design to have any chance of reaching orbit.
Saturn V multi-engine pogo effects were solved by buffering the fuel supply with super-critical helium cells and adjusting the guidance system for smoother steering impulses.
A single solid propellant pogo on the other hand, is more complicated due to fact that you have variances in the solid, no matter how precise the mix is. The Japanese have been tangling with this for some time with success and failures, more failures are recorded though. Go with a clustered booster kit, then would be able to counter most of the pogo with each booster's own vibration frequency.
A Delta-Style cluster kit would resolve this problem and give a higher delta-v impulse to the stack as a whole. The ticklish part would be man-rating the stack with the added solids. One solution would be to stagger the cluster's firing as to maximize the dampening effects. This would add a safety factor in case there's a failure in the cluster at any stage, the opposing elements would be jettisoned along with the failed unit. Then the second stage would simply burn longer to make the orbit, or a contingency plan would kick in, with maximum of life safety.
First rule of holes; When in one, stop digging.
>they do not expect it to delay the goal of returning astronauts to the moon by 2020.
of course not, what's going to delay going to the moon again by 2020 is the fact that congress has no intention whatsoever of paying for that, and no one, not even Bush takes the program seriously.
Why are they wasting money on programs that are going to be thrown right out the window, never to be heard of again, as soon as the next president takes office?
I wish NASA would put more effort into developing gaseous core nuclear rocket engines. There was a nuclear engine project in the late 60s using a solid core reactor, but gaseous core reactors have not been thoroughly explored. Whereas solid reactors melt above about 3500C, a "light bulb" type of reactor consisting of a hollow quartz bulb with a cloud of gaseous nuclear fuel confined in the center could operate at 25000 C, radiating in the ultraviolet range instead of heat per se. In an engine based on this type of reactor, hydrogen flowing past the outside of the bulb would be superheated and expelled as rocket exhaust. No chemical combustion, no radioactive emissions, just heat transfer.
Check out this interesting article, part 10 of a series, about a hypothetical design for a non-polluting, 100% reusable nuclear rocket based on the Saturn V form factor. Using existing engineering apart from the gaseous core reactor, it could lift 1000 tons of payload into orbit (6 times the capacity of the proposed single-use Ares 5 cargo rocket, and 30 times that of the shuttle), and then return 1000 tons of cargo to a powered vertical landing. No expendable fuel tanks, no solid booster recovery, just a big old Flash Gordon style rocketship. This is heavy lifting power that could take up a space hotel or moon base in one shot. It could power enormous ships to Mars in 3 months, not merely to explore but to colonize, carrying hundreds of people at a time, hundreds of tons of equipment and supplies, and highly effective radiation shielding.
I know it's the "N" word, but this rocket wouldn't be a nuclear disaster waiting to happen. If such a ship crashed or exploded and released its entire nuclear fuel load into the atmosphere, the nuclides released would be 1% of what came out of a single 1950s bomb test (and there were many of those).
http://ranier.hq.nasa.gov/Sensors_page/DD/HST&GLL_CCD.html
Bell Labs started development and NASA sponsored more development.
What's with the NASA griping? If you're going to complain about governmental money pits there are much bigger holes to complain about than NASA.
Was it really a conscious decision by one demonizable person, or a prevalent attitude?
To have abandoned a heavy-lift capability like Saturn V, to have dumped such precious knowledge into the equivalent of a junkyard... I think it betrays the attitude that scientific knowledge, however amazing its accomplishments may have been, was considered disposable! And it goes without saying that the people who sweated it out, most visibly the test pilots and astronauts that helped test and prove those technologies (even if at one time they were hailed as the heroes of the whole thing) even their contributions were practically thrown away. Someone who would throw this away would have to be thinking that the effort that was put in by everyone involved was not heroic but ordinary.
I don't think one person could have made such a decision by himself without that prevalent attitude to support it. It would be too... inhuman.
You can't send a takedown notice to an already printed newspaper.
With this new rocket we see the same idiotic non-scientific design. The rocket will be unstable folks. You know it, we know it. Make it look like Soyuz. Nothing will happen, but lives will be saved.
You proved the world that you can live with non-metric non-scientific Imperial measurement system (inches, pounds, arrow flights, feet, elbows, miles, stones, etc.), that the religion is the "best" spiritual foundation of the state. But maybe it is time to say: enough is enough, put the pride on the shelf, and do it right at long last?
According to the articles I've read, NASA massively interfered with getting FAA approval to even test-fly it, repeatedly interfered with any tentative review by the FAA for approval of flight plans involving air craft, and insisted through such back-channel regulation with the FAA that the support structures be massively over-built. The result is that as wonderful as Ariadne was, they were never permitted to seriously consider using NASA's pre-built and under-used launching facilities, even on a rental basis, and that Ariadne's potential payload and maximum height were extremely limited.
Like an early automobile being told by law that they had to pack a spare saddle, such over-engineering made Ariadne much less investment worthy by interfering with its usability and increasing its expense.
Well, the problem as I see it is that the prototype design has diverged so far from the original concept.
The idea was that by using Shuttle components that are (a) in production and (b) have proven safe in their current designs, then (c) by configuring them in a way that avoids known problems, you end up with a safe and economical vehicle much faster.
The problem is that it might not be so simple. The first concept was a Shuttle solid rocket booster for the first stage, an second stage powered by a Shuttle main engine, with a payload that is pretty much a scaled up Apollo service and command module. But apparently this really wasn't going to do the job.
What we have now is a new solid rocket booster as the first stage, and a second stage that look a lot like the Saturn V third stage, powered by a new version of the currently out of production engines, and a new configuration that while avoiding the known problems with the Shuttle, has novel issue of its own. It's not that it won't work, it's just that the vehicle looks a lot less like configuring the best of the Shuttles components into a safer configuration, and more like completely new system. None of the anticipated "built in" advantages applies anymore.
So we're probably in the old "good, fast, cheap: choose any two" scenario. It's not an impossible problem, but denial could be very dangerous.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
YOU, unfortunately, shot your mouth off without understanding what I was saying. I wasn't referring to the little guys.
If you'd followed this very much, you might realize a few things. Over the past few decades, the big boys have made noises about building their own stuff: there's a market in space launch and they'd like to profit from it (much like the Russians are now.) However, all those corporations are heavily dependent upon Federal contracts, and every time they talk about building a commercial launch vehicle of their own, NASA suits start quietly circulating around various boardrooms pointing out that certain juicy contracts are up for renewal, and that it would be a shame if they went to somebody else. My point is that NASA is deliberately preventing the same companies that are building NASA's vehicles from using that experience outside NASA's control. In that sense, NASA politics are holding back greater commercialization of near-space.
That's what I'm talking about, bucko. So try being a tad more civil next time before you starting calling people "dumbest of the dumb", and maybe find out what they're actually talking about before you jump in.
You'll seem smarter that way.
The higher the technology, the sharper that two-edged sword.