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#31
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SpaceX has plans--BIG plans
There may have been engineering challenges in the '50's, but technology and construction techniques have improved significantly since then. It's the unknown unknowns that get you. Materials and construction techniques aren't the problem. Things like injector designs don't necessarily scale up easily when you consider problems like combustion instability. Even if things look like they're going smoothly, you still want to have a robust, somewhat lengthy, ground test period to make sure you're not missing something. This takes time and money even if you don't run into significant problems. You mean the computer simulation isn't accurate? Inconceivable! rick jones -- The glass is neither half-empty nor half-full. The glass has a leak. The real question is "Can it be patched?" these opinions are mine, all mine; HP might not want them anyway... feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH... |
#33
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SpaceX has plans--BIG plans
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#34
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SpaceX has plans--BIG plans
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#35
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SpaceX has plans--BIG plans
On Aug 3, 5:15*pm, Pat Flannery wrote:
On 8/3/2010 7:36 AM, Jeff Findley wrote: I wish them luck, but they'll have challenges. *The F-1 development program was filled with engineering challenges, despite the fact that in many ways it was just a scaled up version of previous LOX/kerosene engines. That may be the problem; Lox/kerosene engine designs don't scale up well, as the Soviets found out with their failed RD-105 engine design; which was based on scaling up the V-2 Lox/alcohol engine technology:http://www.astronautix.com/engines/rd105.htm A photo of it hehttp://www.b14643.de/Spacerockets_1/...nes/RD-105.jpg When the very long combustion chamber shows up, it's a sure sign something isn't working right in the combustion process. Glushko foolishly promised Stalin that it would be easy and quick to develop, and got into real hot water when it flopped. Pat Did Glushko live to retell the experience? Stalin was usually uncompromising when it came to punishment of those who failed to deliver for him. Mayaschev was lucky that Stalin was dead when the M-4 Bison bomber came out: it clearly lacked the range for a round-trip bombing mission to the U.S., and when he told Khrushchev that the plane could hit the U.S. and land in Mexico, Nikita Sergeyich is supposed to have roard back "What do you think Mexico is, our mother- in-law? Even if the plane landed there, they wouldn't give it back!" If Mayaschev had to tell Stalin the same thing, those would be the last words he ever said.....because a 9-mm brain hemmorage would follow shortly thereafter. |
#36
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SpaceX has plans--BIG plans
On 5/08/2010 6:37 AM, Jeff Findley wrote:
Liquid rocket engine development isn't necessarily as quick and easy as some would think. Jeff Seems to be going well for SpaceX. ;-) Two engines; rapid development and only a couple of minor (albeit costly - two prototype vehicles lost) problems in the Falcon 1, but that's been sorted out. The thing that impresses me is the small scale of the operation compared to the scale of achievement. |
#37
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SpaceX has plans--BIG plans
On 8/4/2010 5:18 PM, Matt Wiser wrote:
On Aug 3, 5:15 pm, Pat wrote: On 8/3/2010 7:36 AM, Jeff Findley wrote: I wish them luck, but they'll have challenges. The F-1 development program was filled with engineering challenges, despite the fact that in many ways it was just a scaled up version of previous LOX/kerosene engines. That may be the problem; Lox/kerosene engine designs don't scale up well, as the Soviets found out with their failed RD-105 engine design; which was based on scaling up the V-2 Lox/alcohol engine technology:http://www.astronautix.com/engines/rd105.htm A photo of it hehttp://www.b14643.de/Spacerockets_1/...nes/RD-105.jpg When the very long combustion chamber shows up, it's a sure sign something isn't working right in the combustion process. Glushko foolishly promised Stalin that it would be easy and quick to develop, and got into real hot water when it flopped. Pat Did Glushko live to retell the experience? Stalin was usually uncompromising when it came to punishment of those who failed to deliver for him. Yeah, Glushko lived...he was one of the few people that knew how to make rocket engines, so was too important to have liquidated. Mayaschev was lucky that Stalin was dead when the M-4 Bison bomber came out: it clearly lacked the range for a round-trip bombing mission to the U.S., and when he told Khrushchev that the plane could hit the U.S. and land in Mexico, Nikita Sergeyich is supposed to have roard back "What do you think Mexico is, our mother- in-law? Even if the plane landed there, they wouldn't give it back!" If Mayaschev had to tell Stalin the same thing, those would be the last words he ever said.....because a 9-mm brain hemmorage would follow shortly thereafter. If you think about it, once WWIII broke out, there probably wouldn't be a USSR to return to anyway; at least not the base it came from. The same would apply to our B-52s. Khrushchev used the M-4 Bison's short range and Tu-20 Bear's vulnerability due to its lower speed as a rational to curtail the Soviet strategic bomber program and save defense spending by basing the Soviet deterrent force on a "Biad" of ICBM's and SLBM's, rather than a "triad" like the US had. Even then, he canceled the ICBM version of the Proton rocket, saying "I can build the giant silos for these or socialism; but not both at once". The ICBM version of the N-1 was really something to behold: http://www.astronautix.com/graphics/n/n11gr2.jpg It was based on the second and third stages of the standard N-1. Two or three of these would theoretically be able to destroy all major US cities with huge yield warheads sent in on a depressed trajectory to help avoid ABM's, or into low orbit from which they would descend onto their targets when commanded, allowing an attack from the south to avoid radar detection rather than going over the North Pole like conventional ICBM's. Pat |
#38
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SpaceX has plans--BIG plans
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#39
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SpaceX has plans--BIG plans
On 8/2/2010 9:24 AM, Anonymous wrote:
"Damon wrote in message ... Too much detail to go into here, follow the links: http://commercialspace.pbworks.com/f...M%20small.pptx http://commercialspace.pbworks.com/f...20Propulsion%2 0small.pptx Discusses Raptor upper stage and engine, Merlin 2 engine, Falcon X and Falcon XX, which is a tad larger and more powerful than the Saturn V, and technology for manned deep space exploration. Wow, this all sounds terribly exciting, but none of it is official. What's SpaceX's response to all this? The Ares X and Ares XX sound ambitious, on par with the Saturn V in payload and performance. I assume these are SpaceX's proposals for NASA's Heavy Lift program which Congress has ordered. It will be interesting to see how this will stack up against Boeing's Ares V- derivative, both in cost and development time. Boeing has done next to nothing on Ares V, so in terms of development time they should both stack up pretty evenly. It would be strategically unwise for the U.S. government to put all its eggs (COTS and Heavy Lift) in one basket (i.e. in the hands of one company), so I doubt SpaceX will be allowed to develop Ares XX, but it depends on the price-tag they put on it. If they quote something on the order of $2 billion to $3 billion it will be difficult for the government to resist (Boeing has quoted something like $ 15 billion for Ares-V IIRC). OTOH from the drawings it looks like they're already commited to developing the larger Merlin-2 engine, vital for even attempting to consider something like Ares XX. Good luck SpaceX! If anybody is really interested in these kinds of unaffordable and unsustainable monster zombie vampire Jesus rockets, I am blobbing them again on my new and improved stock Wordpress blog at the same old URL : http://cosmic.lifeform.org Satire. Parody. Call it what you will. And no AJAX development either! As always, you can peruse my papers on these and other subjects, privately, without IP monitoring or tracking, at my ISP repository : http://webpages.charter.net/tsiolkovsky/ Enjoy your anonymous rocket browsing! |
#40
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SpaceX has plans--BIG plans
On 8/5/2010 3:08 AM, Jeff Findley wrote:
I don't think that the actual engine development program at SpaceX was completely smooth. They certainly have some good engineers, but they were still starting essentially from scratch. They deliberately chose a gas generator cycle for their LOX/kerosene Merlin 1 engines (surely partly to control development and operational costs). This was a conservative approach that didn't necessarily push the state of the art in liquid rocket engine development forward, at least in terms of technology. Despite that conservative approach, a quick search of news articles indicates that there was at least one engine failure on the test stand (combustion chamber #13) despite the fact that all of the previous combustion chambers "worked fine". The one that failed tried a radical idea out to cut engine costs; it used a ablative liner on the interior wall of the combustion chamber rather than regenerative cooling. The idea was that this would simplify the engine and lower its production costs, and after booster recovery the combustion chamber would be opened and a new liner inserted before the next flight. Many rocket engine engineers were skeptical of the concept, and it turned out they were correct. During a firing test the liner disintegrated and was blown out of the engine nozzle. SpaceX ditched the concept and went back to the tried and true regenerative combustion chamber cooling concept. SpaceX's triumph may have been _not_ to use any revolutionary technology (other than the parachute recovery of the first stage that has yet to be proven), like so many failed private rocket companies tried (and Roton comes especially to mind in that regard) but rather just stick to tried and true technology and figure a way to cut the cost. Pat |
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