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On Tue, 17 May 2005 21:21:24 -0400, in a place far, far away, "Scott
Hedrick" made the phosphor on my monitor glow in such a way as to indicate that: So we "unreasonable" folk are increasingly frustrated at your inability to let go of the "EVA is hard, and expensive, and rare, and undesirable Because currently it is just that. But not because of any laws of physics--it's because of flawed decisions made in the past. And *not one person* has ever said otherwise. No, they only implied it. Another handwave on your part. ?? If you're going to use hackneyed phrases, you might at least use applicable ones. What you apparently want Herb to do is speculate on the future. No, what we want Herb to do is to recognize that there were not just technological and physical forces driving that decision, but political ones, *None* of which changes the *fact* that no money is being spent on improve EVA capabilities, so *Herb is right* when he says it's poor design to design something that requires an EVA capability that *will not exist* because no effort is being spent on developing it. But since money could be spent on developing it, the point remains pointless. The entire architecture is under planning and development, and part of that architecture could be improved EVA equipment. rest of idiotically condescending nonsense snipped No doubt you'll wave your hands again, instead of providing any real research. "Research"? What does "research" have to do with it? What is it I'm supposed to be "researching"? What strange non sequiturs you come up with. |
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"Michael P. Walsh" wrote in message
... "Pete Lynn" wrote in message ... It would not surprise me if their lack of high purity hydrogen peroxide, (regulatory reasons?), cost them a year. Switching to LOX earlier might have been another way around this. Buying in engines would have been quicker, but excepting the unforseen delays, not cheaper, I expect it would have also constrained them designwise. They can make and develop the less sophisticated type of engines they need much cheaper and faster than anyone else, including XCor. Cheaper quite possibly. Cheaper and faster than anyone else, including XCOR? In theory yes. Not proven by their progress so far. I believe that Armadillo is finding engine development to be a lot harder than they believed it would be when they started. Indeed, their development path has been somewhat circuitous, though they are quick learners in new field, fast becoming experts. I also note that if you are trying to win a time constrained prize then you need to avoid getting into long lead time R&D programs and that is typical of engine development. True, but as you know the X-Prize was never their prime objective, more a self imposed deadline, theirs is a long term low cost sustainable and measured development path. Personally I think they are doing it exactly right. This is the type of integrated incremental design and build typical of serious low cost development in other fields. The one off design mentality more typical in this industry has very high costs and achieves very low levels of refinement, though it is very appropriate within the fixed contract, waste everything but time context. Doing it right for what? In the context of winning a time limited program it is not the way to go and I believe Armadillo's experience shows that. Doing it right not in the context of winning the prize, but in that they a systematically exploring all variations along their development path, continually doing their homework and optimising their design instead of just choosing one flawed approach and trying to make it work. This approach would have worked well for the X-Prize had they been willing to sink more resources into it and speed up their prototyping cycle, but the cost benefit was not there - this is volunteer work and they are taking a more measured approach. Scaled Composites took the high end. They (with the help of Paul Allen's money) competed a new hybrid engine development from two separate contractors. Throwing more resources into the program reduces the risk of not making a fixed deadline in time, although buying an already available LO2-kerosene engine might have provided an even lower time risk, assuming a suitable engine was available on the market. Indeed, while impressive, SS1 did cost what, $20-25 million? In some ways this was not a CATS success story. I still ask myself the question, could the X-Prize have been won for under $10 million? If so how? I suspect that the Armadillo type approach is potentially capable of this, they are truly a CATS operation. Theirs is an ongoing sustainable development path, and I think it is only a matter of time before they eventually start meeting with major success. Armadillo seemingly reached a dead end on the monopropellant H2O2 engine and has moved on to LO2-kerosene. I suspect they have a long program of engine development ahead of them. This is due quite a bit to their limited resources and available expertise. Indeed, though I am sure they will make steady progress. I assume John Carmack is too intelligent to risk his financial health on some kind of attempt to provide a low cost propulsion system or manned operating space vehicle. I think this actually is his intent, though I am sure that he will not risk life or limb on anything that is unsafe or unviable. If it happens, I am sure he will post the results on his website. The openness and honesty of their development has greatly impressed me, it speaks volumes. Pete. |
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On Wed, 18 May 2005 16:18:58 -0400, in a place far, far away, "Scott
Hedrick" made the phosphor on my monitor glow in such a way as to indicate that: "Rand Simberg" wrote in message .. . The point remains that not all people think that EVA is something for the distant, unthinkable future. But the *funding* appears to be. Because NASA is as blinkered as you, apparently (other than the possible exception of the Millennial Prize). They could provide funding for it anytime they choose to do so, just as they are for systems that don't require it. You're still welcome to provide some verifiable examples of *current* funding. A pointless request, in the context of the discussion. But what's new? |
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Rand Simberg ) wrote:
: On Tue, 17 May 2005 21:21:24 -0400, in a place far, far away, "Scott : Hedrick" made the phosphor on my monitor glow in : such a way as to indicate that: : So we "unreasonable" folk are increasingly frustrated at your inability : to : let go of the "EVA is hard, and expensive, and rare, and undesirable : : Because currently it is just that. : : But not because of any laws of physics--it's because of flawed : decisions made in the past. : : And *not one person* has ever said otherwise. : No, they only implied it. : Another handwave on your part. : ?? : If you're going to use hackneyed phrases, you might at least use : applicable ones. : What you apparently want Herb to do is speculate on the future. : : No, what we want Herb to do is to recognize that there were not just : technological and physical forces driving that decision, but political : ones, : : *None* of which changes the *fact* that no money is being spent on improve : EVA capabilities, so *Herb is right* when he says it's poor design to design : something that requires an EVA capability that *will not exist* because no : effort is being spent on developing it. : But since money could be spent on developing it, the point remains : pointless. The entire architecture is under planning and development, : and part of that architecture could be improved EVA equipment. : rest of idiotically condescending nonsense snipped : No doubt you'll wave your hands again, instead of providing any real : research. : "Research"? What does "research" have to do with it? What is it I'm : supposed to be "researching"? I think Scott means that he's unwilling to take your opinion as fact any longer and you'll have to back up what you say with references by doing actual research. : What strange non sequiturs you come up with. I'm sure it appears that way to you. Eric |
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Scott Hedrick wrote:
[... *None* of which changes the *fact* that no money is being spent on improve EVA capabilities, [....] That statement is factually false, Scott. Money is being spent, at low levels, both by NASA and at contractors and at various academic institutions working on various improvements on EVA systems. It is fair and accurate to say "not enough to make reasonable progress", but "no" is grossly inaccurate. -george william herbert / |
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Herb Schaltegger wrote:
On Wed, 18 May 2005 14:04:03 -0500, George William Herbert: [...] Unless the estimated cost to develop and prove it is less than the cost of developing heavy lift alternatives. Only if you presume the requirement to develop heavy lift boosters in the first place. 20 ton chunks will not get us to Mars without some sort of orbital assembly, and only get about 1 person at a time to the Lunar surface. Which is a usefully arguable argument, with "traditional vendor" answers on both sides being in the billions of dollars. My opinion on this matter is that orbital assembly can be simplified and looked at as a special case of the orbital docking or berthing problem. Yes, I agree. Not all docking/berthing mechanisms under consideration are suitable for high accelleration flight, Yes, I agree on this point as well. but many are, and the problem is simplified if you don't have to run a pressurized hatch connection between the vehicles. Very true, although IVA assembly is certainly do-able. Consider the U.S., European and Japanese modules of SSF/ISS as a proof-of-concept, if you will. You need to connect a control run of some sort, but merely plugging in one cable bundle manually in a minimal EVA after the docking is not a high risk EVA activity, True, however . . . once you set the ground rules to allow for EVA assembly tasks of any kind, designers often start adding on other tasks. "Since the crew is going to be outside anyway, why can't they ALSO do . . . " It's a very slippery slope. There are several effective ways of dealing with this, including firing the first couple of people to suggest that during the development program. Creep in various areas is a sign of ineffective management or improperly set constraints. and there are credible unmanned ways of doing it as well (short arm with a plug on the end...). Think "piston" and you've got the right idea. Requires perfect alignment of the two units, which is not necessarily a given for many docking mechanisms. Most will latch across a wide range (or free range) of rotations of the assembly. Small multi-DOF arms are cheap and easy and could even be redundant... Orbital assembly at that level is not nearly as mass efficient as more labor intensive options, but does get you around having to build and buy a HLV. Yes, hence my comment above. It's adequate for Moon/Mars missions. Exactly. Right. As long as there's agreement that plugging large pre-integrated modules together and connecting a few or singular cables isn't outside the range of reasonable off the shelf technology options, we have nothing to argue about on that point. -george william herbert |
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"Pete Lynn" wrote in message ... "Michael P. Walsh" wrote in message ... "Pete Lynn" wrote in message ... Indeed, while impressive, SS1 did cost what, $20-25 million? In some ways this was not a CATS success story. I still ask myself the question, could the X-Prize have been won for under $10 million? If so how? I suspect that the Armadillo type approach is potentially capable of this, they are truly a CATS operation. Theirs is an ongoing sustainable development path, and I think it is only a matter of time before they eventually start meeting with major success. Well, probably a matter of a very long time. And it will depend on just how many resources John Carmack is willing to expend on the program. Armadillo seemingly reached a dead end on the monopropellant H2O2 engine and has moved on to LO2-kerosene. I suspect they have a long program of engine development ahead of them. This is due quite a bit to their limited resources and available expertise. Indeed, though I am sure they will make steady progress. I assume John Carmack is too intelligent to risk his financial health on some kind of attempt to provide a low cost propulsion system or manned operating space vehicle. I think this actually is his intent, though I am sure that he will not risk life or limb on anything that is unsafe or unviable. Risk of ambiguosly wording a reply in a newsgroup. The key words were "too intelligent to risk his financial health". during his attempt to provide a low cost propulsion system or manned operating space vehicle. I assume your reply means you believe he will perservere at developing a low cost manned operating space vehicle, not that he will pursue a path that will risk his financial health. I assume that John Carmack is quite serious in his development efforts, just not convinced that he will achieve his goals. If it happens, I am sure he will post the results on his website. The openness and honesty of their development has greatly impressed me, it speaks volumes. Pete. I try to post with care when I am providing a critique of someone whose efforts I greatly respect. Sometimes I don't word things correctly and people can draw a different conclusion than intended. Usually I can understand where the communication went wrong after I re-read my post. Mike Walsh |
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"Michael P. Walsh" wrote in message
... I assume John Carmack is too intelligent to risk his financial health on some kind of attempt to provide a low cost propulsion system or manned operating space vehicle. I think this actually is his intent, though I am sure that he will not risk life or limb on anything that is unsafe or unviable. Risk of ambiguosly wording a reply in a newsgroup. The key words were "too intelligent to risk his financial health" during his attempt to provide a low cost propulsion system or manned operating space vehicle. Sorry for my ambiguousness. I meant to say that I think they are very intent on providing the low cost manned space vehicle, and that they have no intention or need to take any such risks. One thing that might potentially compromise such financial health would be a rash development program that lead to a serious accident for which there might also be serious and unmitigated financial consequences. This was one of the conclusions I was jumping to. I suppose the point I was trying to make was that low cost development in no way precludes due care with regard to economic viability and public safety. The two objectives can be fairly independent. I assume your reply means you believe he will perservere at developing a low cost manned operating space vehicle, not that he will pursue a path that will risk his financial health. Yes. I assume that John Carmack is quite serious in his development efforts, just not convinced that he will achieve his goals. They continue to make steady progress and unlike many others are not deadline constrained. It is an open ended sustainable development program, so it would seem to me that excepting some external difficulty, they eventually must get somewhere. Yes, this might take a while. Their primary concern might be, being overwhelmed by the boom/bust competition, though I expect this unlikely. Even then they might still carve out a niche for themselves. Pete. |
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Michael P. Walsh wrote: Well, probably a matter of a very long time. And it will depend on just how many resources John Carmack is willing to expend on the program. I still like Canadian Arrow's approach- somewhere out there, von Braun and Bonestell are smiling: http://www.canadianarrow.com/vehicle1.htm Now that, by God, is a rocketship! Even landing the first stage in the sea is right out of von Braun's Ferry Rocket ideas, and they get extra points (just like SpaceShipOne) for using round portholes, like rocketships are supposed to have. The pity of it all is that this gizmo could have been built around 1950, instead of 55 years later. The co-CEO of the corporation looks like Captain Nemo, and that is really ubercool also: http://www.canadianarrow.com/kathuria.jpg Right up to the time that British military aircraft start getting mysteriously rammed by a strange black V-2 look-alike rocket launched from inside an extinct Pacific volcano. :-D Pat |
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"Pat Flannery" wrote in message ... Michael P. Walsh wrote: Well, probably a matter of a very long time. And it will depend on just how many resources John Carmack is willing to expend on the program. I still like Canadian Arrow's approach- somewhere out there, von Braun and Bonestell are smiling: http://www.canadianarrow.com/vehicle1.htm Now that, by God, is a rocketship! Even landing the first stage in the sea is right out of von Braun's Ferry Rocket ideas, and they get extra points (just like SpaceShipOne) for using round portholes, like rocketships are supposed to have. The pity of it all is that this gizmo could have been built around 1950, instead of 55 years later. The co-CEO of the corporation looks like Captain Nemo, and that is really ubercool also: http://www.canadianarrow.com/kathuria.jpg Right up to the time that British military aircraft start getting mysteriously rammed by a strange black V-2 look-alike rocket launched from inside an extinct Pacific volcano. :-D Pat I am somewhat concerned that Canadian Arrow's approach will lead to some kind of disaster that will put a black mark on small scale private space efforts. Thank you for your reference. I see that they have done some significant engine firing tests. However, they need a lot more effort and testing on that escape capsule. Dropping it from a helicopter is a good first step, but testing the escape capsule should be regarded as essential by them before they commit to a manned launch. At least now they aren't pushing to make an X-Prize date so they should be able to concentrate on getting things to work without cutting corners in hopes of winning a prize. Mike Walsh |
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