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#21
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High Launch Costs - Result of Physics?
You can't heat something like green beans on a stove
without using extra water. Mary Shafer wrote: You're kidding, aren't you? I can heat sauteed green beans in a skillet with no added water. Ditto stir-frying. Okay, extra *liquid* then. I chose to speak of water because it doesn't change the nutritional characteristics -- or, generally, the taste -- of the food. I suppose, technically, one *could* fry vegetables on a dry skillet over a wood fire, or roast them, but they'd totally lose their "fresh" flavor in the process. And I apologize for the extra-strength tangent. I will try to exercise restraint and no longer respond to Mr. Ordover. |
#23
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High Launch Costs - Result of Physics?
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#24
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High Launch Costs - Result of Physics?
(John Ordover) wrote in message . com...
(Alex Terrell) wrote in message . com... "Christopher M. Jones" wrote in message ... That's just plain idiotic. There are cars from 2003 which can out-perform the average car today. Sheesh. Get a dictionary, look up the word "tautology". Or do you want to compare Thrust SST to one of those cars from 1969? Looking to the thread topic, I see the subject is *cost*, not speed. Shouldn't you be comparing the "amount of car" you get for a dollar (inflation adjusted, of course) now vs. in the 1800s? I would bet that it's quite a bit more now than then. Oh, and I suppose they had gas-electric hybrids for sale in 1899 right? With airbags. And air conditioning. And power steering. And anti-lock brakes. And 50 mpg gas mileage. I've seen some of the NCAP crash tests. Two years ago the Citroen C5 was the first car to get 5 stars. Now a dozen cars have five stars, and if your car is over 5 years old, it's probably a deathtrap compared to today's cars. The improvement, as you point out, is amazing. Does it run by something other than an Internal combustion engine? Do you want Floo Powder? Our computers still use silicon, and run on electricity, just as they have for the last 30 years or more. According to your argument, they can't have progressed either. |
#25
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High Launch Costs - Result of Physics?
All the points below seem to indicate that high launch costs are a
result of economics, not physics. With a high enough volume, unit costs tend to come down to the point where raw materials are a significant, if not the dominating factor. I think a car costs about 10 - 20 times the cost of the basic raw materials. I also think (I am prepared to be corrected) that a modern car is actually more complex than a modern rocket, in terms of number of components and assembley. A modern car costs about $2 billion to develop, which is more than an expendable rocket. Let's suppose there were no economic limitations, and production of rockets was in the millions. What orbital launch cost would result from a rocket cost of 20 times the material cost? Cheap! So the key question is not whether economics or physics is cause of high cost, it's can: 1. The economics be overcome 2. Can some physics / engineering advance be used to change the economics (John Ordover) wrote in message . com... "Christopher M. Jones" wrote in message ... "jeff findley" wrote: You're asking all of us to give up and wait for a miracle. The first automobiles were hidiously expensive. The first airline flights were also. So were the first microprocessors. What made all of the products that use these various technologies more affordable wasn't some magic technology. The technology is largely the same for most of these. Interestingly, microprocessors now would be much more expensive than most computers were in the 50s and 60s if each fabrication plant only produced one cpu. Those plants cost billions of dollars for state of the art chips, but they produce so many that the cost is amortized down to a pittance per chip. That's because there is a huge volume of customers, so they can sell a heck of a lot of chips. Similarly, if the cost of a launch vehicle were even many billions of dollars to build but was highly reusible with very low incremental costs (i.e. fuel and minimal labor) the per flight cost would be rediculously cheap as well. Only if there were as many customers for launches as for chips. But there aren't, and won't be, because there's nothing valuable in space go to and bring back... Jumbo jets cost tens and hundreds of millions of dollars, but fly so often that the ticket price is mostly due to fuel and labor costs. ....and no one to visit or do business with. As I've pointed out more than once on these newsgroups, the technological capability to do RLV SSTO launch vehicles using LOX/Kerosene (a propellant mixture that the current generation of aerospace blue- noses don't much care for, despite its obvious advantages) is very nearly on the shelf. Existing and historical rocket stages should be capable of SSTO operation with only minor upgrades. With only *slightly* improved engine, design, construction, and materials it should be abundantly possible to build an RLV SSTO capable of routine operations with low incremental cost (e.g. using composite structures, slightly upgraded engines, advanced alloys, and low-maintenance thermal protection systems). To sell rides to whom? To do what? We have the technology, what we lack is the right people with enough funding and the right designs. No, you lack customers and a profit motive. Scatter a trillion dollars in gold bullion on the Moon, private industry will get us there. As long as the Moon is only a dirty beach - well, we have dirty beaches right here. |
#26
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High Launch Costs - Result of Physics?
John Ordover wrote: But I guess the important point is that we don't need to prove anything to the Ordovers of the world. I am exactly the kind of person you have to convince if you want investors who would just as soon invest in cheese as space. You have to show the short-term profit return. You throw out terms like "infrastructure will be developed" that seem to assume that infrastruture will appear from nowhere, at no cost, by magic. The reality is that the infrastructure you describe is wildly expensive, and no one wants to pay to put it in place. I don't believe that there is a short-term profit potential in space that would justify any substantial private sector investment. It will require billions of dollars to develop an RLV large enough to handle existing markets, and with low enough recurring costs to develop new markets. The only potential market large enough to make that kind of investment pay off is LEO tourism, and with exactly 2 customers through the gate so far I don't blame anyone for being sceptical about the size of the potential market. I personally own several thousand shares of Boeing stock, but I have not invested a single red cent in any start-up launch vehicle or X-Prize company, and don't intend to. I think the government is going to have to take the first step by developing a true RLV, and by making it as simple and reliable as possible to keep support costs to a minimum. After that, I think you will be shocked at how quickly things develop. Unfortunately, I see little evidence that NASA is interested in doing any such thing in the forseeable future. NASA, for the last 30+ years, has been fixated on pushing the technology envelope and on doing things the hard way in order to "justify" a lot of technology development to make more work for their research centers. That approach virtually guarantees high costs and low reliability. In the case of NASP and X-33, it guaranteed outright failure. Where you are going wrong, IMHO, is in assuming that it will require technology breakthroughs to develop a reliable, fully-reusable launch vehicle. You seem to think that the Shuttle has done the best that can possibly be done with existing technology, which is an incorrect assumption. The politicians and bureaucrats FUBAR'd the Shuttle design right from the start and it never had any chance of reducing costs. You appear to lack the engineering experience to understand how much better we could have done even at the state of the art in 1970. A 2-stage, VTOL RLV has been within the state-of-the-art for 30 years, but NASA is uninterested in such an unglamorous approach. Instead, we got stuck with a complex, partly-expendable design like the Shuttle, and to replace it NASA chose aerodynamically complex horizontal landing SSTO designs, which are beyond the state-of-the-art even now. The bottom line is that we don't have low cost space transportation now because most of the politicians and bureaucrats have never been able to find their a******* with both hands in order pull their heads out of same. God only knows when this situation will change substantially for the better, so, in the meantime, I would recommend you put your money into cheese futures. |
#27
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High Launch Costs - Result of Physics?
I also think (I am prepared to be corrected) that a modern car is
actually more complex than a modern rocket, AIUI, a rocket is more like a jumbo jet than a car, in the sense of the sheer *amount* of work that must be done to build it, and the number of systems required. Both rockets and jets require years of lead time to build. Automobiles come off the line one per day. |
#28
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High Launch Costs - Result of Physics?
John Ordover wrote: Sigh. The market is all but dead. Satellite service expansion into Asia is plummetting as the cell towers make headway. Just a few weeks ago Arianespace Flight 161 placed a few stud hoss geostationery communications satellites for Australia and Japan. Hop http://clowder.net/hop/index.html |
#29
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High Launch Costs - Result of Physics?
Such a King could not have wanted to build a
Montgolfiere without knowing what a Montgolfiere actually is, And such knowledge was not to be had in 1500 at any price. That is why a flight as earlier described would have needed 'pixie dust' in 1500; not for any lack of physical wherewithal. Hell, the Romans probably had the physical means for balloon building. They just didn't know how, just as the present USA probably possesses the industrial means to build a starship but for many years will not know how. |
#30
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High Launch Costs - Result of Physics?
Len wrote: Michael Walsh wrote in message ... Len wrote: Michael Walsh wrote in message ... Len wrote: ...snip... So far what I consider "baseline knowledge" is the Space Shuttle. ...snip.... Mike Walsh Aha. At last I realize why we disagree on cost estimates for development of a space transport. You believe the Space Shuttle is a good data point; I believe it is an incredibly lousy data point from the economics point of view. In the context of what I was discussing when I made this particular comparison I believe the "baseline knowledge" I was referring to was the aerothermodynamic environment on re-entry of a winged body vehicle. I maintain that integrating the propellant tank results in a much more benign reentry environment as a result of much lower planform loading. The effects, IMO, tend to compound: lower temperatures yield lighter TPS and that leads to lower planform loading that leads to lower temperatures, etc. I understand that, although I don't have a sufficient background in that particlular area to quantify it. My concern was that you are working in a region that is still not well defined. And as far as economics goes, it is a real data point. Got any others? No. But I'd rather consider the set of data to be empty --rather than a set containing only bad data points. I don't disagree with your outlook. However, one point of view is that the high cost of Shuttle operations provides more of an opportunity to demonstrate a market for something like crew transfer to a space station. The only other ones that can be used are capsules such as Mercury, Gemini, Apollo and Soyuz. Which we probably both agree aren't appropriate. Yes, although a capsule design could be a reasonable choice for an ISS escape system. I understand that the OSP program is looking at that possibility. The basic problem is that the only real data points are incredibly lousy from an economics point of view. However, if you re-read my post you should realize that wasn't what I was describing. OK. When it comes to Shuttle, my fuse is probably too short. My main observation is that our relative orientation with respect to acceptable data may explain the gap between us on cost estimates for what may be possible. That doesn't meen that you may not be right; moreover, you are entitled to your opinion with respect to what are reasonable cost estimates --the range of which are probably very unpredictable at this time. I just hope to be somewhat convincing that the low end of the range should not be dismissed as completely impossible. We have discussed this before. I agree that the Shuttle is a bad example for cost comparisons. I have mentioned in the past that whenever I see costs given for any kind of government program whether NASA or DOD the costs seem to be $500 million + for almost any significant program. The DOD is now trying to do some low end tests to deliver small satellite payloads and it will be interesting to see how they progress. One very basic problem is when I read the proposals by private entrepeneurs it reads as if the problem they are resolving would be of more interest to the military than a private investor trying to make money by putting satellites into orbit. A tourist trade could well be a paying business, but there seem to be a lot of "iffy" items that fall in the regulatory and political area that would cause concern to an investor. Mike Walsh |
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