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NASA Encounters Problems With Ares 1 Launch Vehicle Design
Kevin Willoughby wrote:
When is the last time we designed a manned launcher based on the only launcher that has killed its crew? OMG! and when you get past the cold sweats over that, you can worry about how many passengers fly in aircraft designs that have crashed, or based on designs that have crashed. It's TENS OF MILLIONS, man! O the humanity... Monte Davis http://montedavis.livejournal.com |
#92
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NASA Encounters Problems With Ares 1 Launch Vehicle Design
OM wrote: ...Of course, if the X-Prize allowed expendable vehicles, every single entry would have probably been based on Little Joe designs. In fact, I bet there's still enough spare parts floating around in that one Florida junkyard to build at least three :-) I always pictured a manned capsule on top of this: http://yellowjacketsystems.com/jimba...tos/Hb_01a.jpg To keep the acceleration tolerable, the motors would be fired as two opposing pairs one after the other. Here's some great shots of a restored Nike Hercules base BTW: http://www.clubphoto.com/_cgi-bin/ap...k_code=sa01_17 Pat |
#93
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NASA Encounters Problems With Ares 1 Launch Vehicle Design
Henry Spencer wrote:
In article , Kevin Willoughby wrote: I don't think NASA ought to be designing any new launch vehicles. Part of NASA's charter is to do R&D. To advance the state of the art, you pretty much have to design and fly new things. Oddly enough, NASA's predecessor, the N.A.C.A., managed to advance the state of art in aviation immensely despite rarely building a full-sized aircraft. They built wind tunnels, they built model aircraft, they flew modified versions of existing aircraft, and once in a loooong while they built a full-size X-plane... which usually ended up in a scrapyard or a museum within a few years, when its job was done. At no time did they attempt to run their own airline. NASA could do the state of the art in launchers a tremendous amount of good by building and flying some X-rockets, to do flight tests of a long list of interesting concepts that have never made it off drawing boards. Don't hold your breath. NASA doesn't do launch-vehicle R&D any more. In fact, NASA doesn't really do much R&D of any kind any more -- what little remained is being cut drastically to help finance VSE. As a friend of mine said at Space Access last spring: "NASA is well and truly out of the R&D business -- they're going to focus on their core competencies." Hmm.. What are the odds that someone would be able to fly the Linear Aerospike engine if it were not earmarked for a specific NASA flight program? Or, worded differently.. what would happen if someone wanted to fly the already developed hardware? would it be possible? Seems to me that there is the potential that a lot of specific research items are getting buried when their overall program is axed that might be of use in other commercial ventures not related to NASA. |
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NASA Encounters Problems With Ares 1 Launch Vehicle Design
Charles Buckley wrote:
What are the odds that someone would be able to fly the Linear Aerospike engine if it were not earmarked for a specific NASA flight program? I'm guessing they've already robbed the J-2 out of it for ESAS. Or, worded differently.. what would happen if someone wanted to fly the already developed hardware? would it be possible? We'll see when the shuttle retires and people start clamoring for SSMEs. Seems to me that there is the potential that a lot of specific research items are getting buried when their overall program is axed that might be of use in other commercial ventures not related to NASA. This is NASA we are talking about, what did you expect. They're crawling all over Apollo hardware to see how it worked. http://cosmic.lifeform.org |
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NASA Encounters Problems With Ares 1 Launch Vehicle Design - WARNING! Thread Hijacked by Elfritz The Nazi
On Mon, 20 Nov 2006 09:48:43 -0600, kT wrote:
http://cosmic.lifeform.org ....Well, the goosestepping retard munged his alias again. PLONK OM -- ]=====================================[ ] OMBlog - http://www.io.com/~o_m/omworld [ ] Let's face it: Sometimes you *need* [ ] an obnoxious opinion in your day! [ ]=====================================[ |
#96
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NASA Encounters Problems With Ares 1 Launch Vehicle Design
"Pat Flannery" wrote in message ... wrote: Pat Flannery wrote: Even if you build Ares V, you are still going to have to build something else to get crews to the ISS, Why? Because it's not economical for the crew/light cargo mission - each Ares V is going to cost at least twice as much as a Ares 1 due to it using two SRBs and having a far bigger two-stage core assembly. But it's big enough you could launch it twice a year (assuming six month crew rotations) with the cargo you need for those six months. Plus it's the fixed costs that dominate Ares. When you're talking about two ISS crew rotations and possibly two lunar missions per year, the money "saved" by using the smaller Ares I will likely never pay for its multi-billion dollar development costs. There's also the reliability factor to consider - with its two SRBs, Ares V has a built-in SRB catastrophic failure probability that's twice that of Ares 1 While I don't like SRB's, I'd rather see a vehicle with two four segment SRB's than vehicles with five segments, simply because there is more commonality between them and the current shuttle SRB's. A single five segment SRB still seems like a bad idea from development and safety viewpoints. Which would make perfect sense if the extra running costs of taking the truck to the store were lower than the cost of buying and running a car to do the trip. Similarly, if the full cost of five Aries V launches (including development, launch site maintenance etc) is lower than the cost of four Aries 1 launches and one Aries V launch each year, then launching crew on a launcher with twice the required payload capacity makes perfect sense. It's quite conceivable that the costs of operating two launchers rather than one could easily swallow up any savings from one launcher having lower base costs per launch. I depends on how many total launches you have in mind... if it's something like ten or twenty, then maybe just going for Ares V makes sense as your sole launcher. If you end up with around 100 launches desired, of which only 20 need the Ares V's lifting capability, then you probably end up saving money by going the two booster route. I think you're living in a fantasy world if you think NASA would need 80 Ares I launches. I think they'll never get past an average of four to six manned launches per year (two to ISS and the remainder to ???), which means a program that will run for something like 15 to 20 years. If past experience is anything to go by, once made Ares 1 will end up being used for a very long time and for missions that are unforeseen nowadays. Imagine if you went back to the original Thor IRBM design team and told them that around 50 years down the line, a much evolved version of their missile would be landing rovers on Mars Doubtful due to the way NASA has been running Saturn/Shuttle/Ares. It will always remain a NASA only launch vehicle. Note that NASA was banned from selling launches commercially after the Challenger disaster and the Air Force will continue to use EELV's for their launches. Once bitten, twice shy. Even more so, if you use a semi truck to drive everywhere and then you buy a small car for the trips where it 'doesn't make sense', and the truck then spends most of the time sitting on your driveway, pretty soon your wife will be nagging you to get rid of it. Just as it's much easier for Congress to scrap an Aries V that flies once per year to launch big payloads on mega-missions than to scrap an Aries V which flies multiple times per year and is the only manned launcher you have. The two problems with the annual mega-mission idea is that the mega-mission can only go to one destination, and you've still got all that upkeep and infrastructure to maintain in the other eleven months of the year eating up your money, just like the Shuttle does when it's been grounded. How would Ares I/V avoid high infrastructure costs? It's looking to be a very low flight rate system that uses much of the shuttle infrastructure but will be supporting two launchers instead of one. Also, I'm pretty sure this now takes two Ares V launches per manned Lunar mission using the present weight Orion CEV and the promulgated Lunar lander. If we're not going to do the Lunar missions, then there's no reason to build Ares V at all, because we intend to finish up our diminished ISS with the Shuttle, and there's no real need for another station in the near future after that. If we don't go back to the moon, there's no need for Ares I either. A reasonably sized capsule can be built to service ISS and can be launched on an EELV. If you drop the lunar mission, the size of the service module drops *considerably*. NASA looked at making a "tuna can" SM for the Apollo CM for Earth orbit missions, but it was easier just to delete extra tanks and hardware from the existing luanr design. Eliminate the lunar requirements and the CEV goes back to being a "single use" sort of vehicle that's a lot easier to make lighter. Jeff -- "They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety" - B. Franklin, Bartlett's Familiar Quotations (1919) |
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NASA Encounters Problems With Ares 1 Launch Vehicle Design
"Kevin Willoughby" wrote in message ... In article , says... I don't think NASA ought to be designing any new launch vehicles. Part of NASA's charter is to do R&D. To advance the state of the art, you pretty much have to design and fly new things. R&D ought to be X-vehicle programs that benefits the US launch industry as a whole, not NASA specific launch vehicle programs that don't push the state of the art in much of anything. Jeff -- "They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety" - B. Franklin, Bartlett's Familiar Quotations (1919) |
#98
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NASA Encounters Problems With Ares 1 Launch Vehicle Design
Jeff Findley wrote: But it's big enough you could launch it twice a year (assuming six month crew rotations) with the cargo you need for those six months. Yeah... but do you need _that_ much cargo for six months? Maybe with the full six-man crew you would, but at its present crew status that seems excessive. And the problem is, unlike the Shuttle, the CEV isn't designed to bring cargo back from the ISS. So you've lost your "Quark" style dump truck when it's retired. I imagine the ESA Jules Verne module will get pressed into service for this, carrying trash to a destructive reentry like a oversized Progress. One thing you could do is carry a spare Orion up to the station on a dual Orion Ares V launch, so that he station would finally have a six person lifeboat on it and could be fully crewed. After it's attached you start playing the "Switch The Soyuz" game and each new Orion flight to the station takes the Orion already there home while leaving their own in its place. But you only need a single Ares V to do that. Ares V would have been great for building the station, as it could have been made up of fewer, far larger, modules. But once it's built, do you really need that much cargo capacity? Plus it's the fixed costs that dominate Ares. When you're talking about two ISS crew rotations and possibly two lunar missions per year, the money "saved" by using the smaller Ares I will likely never pay for its multi-billion dollar development costs. I was very skeptical when I first saw it, but that DIRECT concept has a lot going for it. It's considerably more capable than Ares 1, but not so huge as Ares V, and that would seem a good size for it to be. All-in-all, I 'm going to be very surprised if either Ares 1 or Ares V (in particular) ever end up on a launch pad. Certainly, NASA's recent history of manned spacecraft development doesn't exactly inspire confidence in this regard. There's also the reliability factor to consider - with its two SRBs, Ares V has a built-in SRB catastrophic failure probability that's twice that of Ares 1 While I don't like SRB's, I'd rather see a vehicle with two four segment SRB's than vehicles with five segments, simply because there is more commonality between them and the current shuttle SRB's. A single five segment SRB still seems like a bad idea from development and safety viewpoints. We'd have to check with Scott on this one, as I don't know if they intend to change the nozzle design or change the fuel composition or center bore design to give it improved performance without overstressing the casing (i.e. same burn time at greater thrust, or longer burn time at the same thrust). Did they fire a five segment one already in a early test? Something about that rings a bell. I depends on how many total launches you have in mind... if it's something like ten or twenty, then maybe just going for Ares V makes sense as your sole launcher. If you end up with around 100 launches desired, of which only 20 need the Ares V's lifting capability, then you probably end up saving money by going the two booster route. I think you're living in a fantasy world if you think NASA would need 80 Ares I launches. I think they'll never get past an average of four to six manned launches per year (two to ISS and the remainder to ???), which means a program that will run for something like 15 to 20 years. Once Ares 1 gets built, they'll start looking around for new missions for it to perform so as to keep it in use; it's capable of carrying a very good-sized payload into LEO; with a new third stage, or by lengthening the second stage, you could send some good-sized probes to the planets. If past experience is anything to go by, once made Ares 1 will end up being used for a very long time and for missions that are unforeseen nowadays. Imagine if you went back to the original Thor IRBM design team and told them that around 50 years down the line, a much evolved version of their missile would be landing rovers on Mars Doubtful due to the way NASA has been running Saturn/Shuttle/Ares. It will always remain a NASA only launch vehicle. Note that NASA was banned from selling launches commercially after the Challenger disaster and the Air Force will continue to use EELV's for their launches. Once bitten, twice shy. I doubt it will get used commercially - that will remain the Atlas V/Delta IV market (or whichever one BoeLockMart decides to stick with), but I can see NASA using it for a lot of science missions because of its payload capacity. The two problems with the annual mega-mission idea is that the mega-mission can only go to one destination, and you've still got all that upkeep and infrastructure to maintain in the other eleven months of the year eating up your money, just like the Shuttle does when it's been grounded. How would Ares I/V avoid high infrastructure costs? It's looking to be a very low flight rate system that uses much of the shuttle infrastructure but will be supporting two launchers instead of one. That's indeed the problem, and that's why I think what will happen if this program goes forward is that Ares 1 will get built, and Ares V never be built, as it costs too much. Unfortunately, that nails the Moon mission this is supposed to all be about, but you can see that happening, can't you? And that's why the DIRECT design appeals to me- it allows fairly heavy cargo to be carried to the ISS, and it also allows the Moon mission via orbital assembly. If you're only get one new rocket, that's the one to go for. If we're not going to do the Lunar missions, then there's no reason to build Ares V at all, because we intend to finish up our diminished ISS with the Shuttle, and there's no real need for another station in the near future after that. If we don't go back to the moon, there's no need for Ares I either. A reasonably sized capsule can be built to service ISS and can be launched on an EELV. If you drop the lunar mission, the size of the service module drops *considerably*. NASA looked at making a "tuna can" SM for the Apollo CM for Earth orbit missions, but it was easier just to delete extra tanks and hardware from the existing luanr design. Eliminate the lunar requirements and the CEV goes back to being a "single use" sort of vehicle that's a lot easier to make lighter. If you designed the Orion so that you could use it as a personnel carrier, a cargo carrier with minimal crew*, or a mixture of both (removable seats) you could end up with a vehicle that has a lot of mission flexibility, like the Soyuz/Progress design. Space given to propellants in the Orion SM, could be used for additional cargo, or alternately the SM's engine could be used during ascent into orbit to allow the total payload weight to LEO to be increased. In short turn it into a combined third stage/retro module. * Or for that matter, no crew; either develop a simple cargo module to replace the capsule, or leave the capsule in place, and give a six-person ISS crew a set of folding seats they can attach in it for use as a lifeboat. Every time a new cargo Orion arrives the old one's capsule is filled with things that can be returned to Earth (experiments and garbage) and the emptied new one becomes the new de facto lifeboat. Pat |
#99
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NASA Encounters Problems With Ares 1 Launch Vehicle Design
"Jeff Findley" wrote in message
... R&D ought to be X-vehicle programs that benefits the US launch industry as a whole What, and have Airbus scream 'subsidy'? :-) |
#100
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NASA Encounters Problems With Ares 1 Launch Vehicle Design
In article ,
Charles Buckley wrote: NASA could do the state of the art in launchers a tremendous amount of good by building and flying some X-rockets... Don't hold your breath. Hmm.. What are the odds that someone would be able to fly the Linear Aerospike engine if it were not earmarked for a specific NASA flight program? Or, worded differently.. what would happen if someone wanted to fly the already developed hardware? would it be possible? It would be distinctly tricky, I'm afraid, because that hardware came about in a cooperative effort funded by both NASA and LockMart, which would probably mean getting both of them to sign off on using it. And the User's Manual :-) might well be Rocketdyne proprietary info, just to complicate things further. I wouldn't say it's impossible, but I would guess that it would require serious political clout, and quite possibly a certain amount of cash, to pry this particular project loose. That *is* an unusually complicated case, mind you. Seems to me that there is the potential that a lot of specific research items are getting buried when their overall program is axed that might be of use in other commercial ventures not related to NASA. Yep, quite likely. The problem often is that they're only half-finished, and are of limited use in that state. (For example, XCOR's work on nonflammable composite LOX tanks had demonstrated feasibility of the materials concept, but hadn't fully solved the fabrication problems of building complete tanks with it.) -- spsystems.net is temporarily off the air; | Henry Spencer mail to henry at zoo.utoronto.ca instead. | |
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