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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.'
...before it's built. Seems like a non-story.
so they found a problem with a preliminary design. big deal. that's why they call it research and development.
how long did it take to design the saturn Ib/saturn V and make sure that they'd mate well with the apollo capsule? how long did it take to come up with skylab, an orbiting lab that could be mounted on a saturn V?
i expect it'll take about five to six years to bring the orion program to a complete first generation system.
when religion is no longer the opiate of the masses, governments will resort to real opiates.
You mean they didn't get the design of a prototype exactly right on the first try? Amateurs! Seriously though, where is the news here?
today is spelling optional day.
If anyone else has read Diane Vaughan's Challenger Launch Decision, he or she will know that launch schedule pressure from upper management was a leading cause of the rationalization of risk that NASA undertook to justify flying with known Shuttle desgign flaws. Hopefully, in this case, the NASA senior managers are not applying the same mindless schedule pressures that leads to quick fixes and mindless workarounds at the expense of long term safety.
We all know what to do, but we don't know how to get re-elected once we have done it
It's a harmonic vibration issue apparently, and these are generally solved quite easily. Adding or removing stiffness, a spiral wrap of an energy dissipating elastomer, isolation mounts, ading or removing mass (or simply moving mass around)... doesn't look like it's a severe issue at this early of the design stage. Someone's just being alarmist.
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.
She can't hold much longer, captain!
Management....wants....a....launch....so....shut....the....fuck....up, Scotty!
Table-ized A.I.
Actually, NASA's ROI is pretty good at about $7 returned for every $1 spent. They also develop a lot of technology that doesn't have a financial ROI, but rather a simple non-tangible benefit to society as a whole. For example, they developed the CCD imager for use in the Hubble Telescope. That technology is now widely used in inexpensive digital cameras but is more importantly also used in medical imagers for detecting breast cancer. It has eliminated something like a half a million unneeded biopsies which not only save that cost, but also the pain from the procedure itself.
Bill
It's my Sig and you can't have it. Mine! All Mine!
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.
No, NASA gave it up years ago - as it simply doesn't work. The turbines are too heavy, useful for too small a portion of the flight profile, etc... etc...
Two more ideas that don't work, despite years of fanboy cheerleading for them. Among other large drawbacks - you still need to get a substantial portion (99%+) of the required velocity from rockets, but the weight of the structure needed to withstand these methods of 'assisting' means a rocket launched this way is actually larger and heavier than one that launched in a conventional fashion.
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.
http://en.wikipedia.org/wiki/Blue_streak
http://en.wikipedia.org/wiki/Black_Arrow
These rockets were a departure from everything else around, and used Hydrogen Peroxide as an oxidiser - cheap, readily available and works well at normal temperatures and pressure. Most considered the fuel to be too hazardous, and a Hydrogen Peroxide fuelled torpedo allegedly sank the Kursk (probably not sensible on a submarine), but the British developed ways to handle it safely and efficiently. To this day, no one else has tried this method and its pretty advanced rocketry even forty years on. It certainly gets rid of the dangerous handling of liquid oxygen, which has to be kept ultra cool and under controlled cryogenic conditions.
After a textbook final launch, the project was cancelled. Given the need for commercial satellite launches over the past few decades, the mind boggles as to how cheap and useful this could have been if developed further. The British, as per usual, decided that simply reusing the Scout solid fuelled rocket would be cheaper. Go figure.
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).