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cheap access to space - majority opinion
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#12
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cheap access to space - majority opinion
Here is more detailed description of the system
of Earth-to-orbit transportation I have described in the first post: http://www.islandone.org/LEOBiblio/SPBI114.HTM |
#13
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cheap access to space - majority opinion
William Mook wrote:
Well, if you want cheap, reliable and tested, you're talking about modifying existing hardware. Big mistake! All existing liquid fuel engines have expensive turbopumps which are designed for minimum weight rather than maximum durability. This is not the best way to make a reusable spacecraft. ...Meanwhile, tank 4 re-enters and is recovered as in the other six tanks. The first stage tanks may be recovered by landing like a plane (e.g., russian Baikal). The second stage tanks will break during reentry unless they are heavy tanks of the pressure fed rocket. Recovering the third stage tanks is very difficult. By the way, some news servers ignore very long posts. |
#14
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cheap access to space - majority opinion
I agree on all your points Andrew. However, the difficulties you
detail are fully addressed by the technologies developed for SSTO. That is, while SSTO wasn't funded at levels to guarantee success, SSTO did some amazing things - and those things address the issues you raise. So, you can count these as solved problems - that make a common element for a multi-element launcher a reality. Since a multi-element vehicle is not as constrained by structural fraction as SSTO - it is achievable with today's technology - virtually off the shelf. This is the second time I've responded to this point - my bit bucket must be very large. Cheers Andrew Nowicki wrote in message ... William Mook wrote: Well, if you want cheap, reliable and tested, you're talking about modifying existing hardware. Big mistake! All existing liquid fuel engines have expensive turbopumps which are designed for minimum weight rather than maximum durability. This is not the best way to make a reusable spacecraft. ...Meanwhile, tank 4 re-enters and is recovered as in the other six tanks. The first stage tanks may be recovered by landing like a plane (e.g., russian Baikal). The second stage tanks will break during reentry unless they are heavy tanks of the pressure fed rocket. Recovering the third stage tanks is very difficult. By the way, some news servers ignore very long posts. |
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cheap access to space - majority opinion
Joann Evans wrote in message ...
william mook wrote: Joann Evans wrote in message ... william mook wrote: This would also help the US contain missile proliferation. If a low-cost RLV of the type described here were operational by a US based firm, it would undercut the rationale others in other nations have (as in Korea) for building an expendable launch vehicle. As a commercial satellite launcher for world markets, yes. Some nations who can't build (or buy) RLVs will still look at ELVs to maintain an independent launching capability, however. Yes, absolutely. But, their motives will be clear to everyone, which will make things easier for our State Department. And of course (espically in Korea's case), they will still want ELVs as medium and long range weapons. But they won't have the fig leaf of space launch development. That's the point. They will clearly be developing weapons systems to threaten us and any coalation that we can assemble who is similarly threatned. Again, this makes things easier geopolitically for the US to contain missile proliferation. The fact that the other guy operates a fleet of RLVs won't affect that. (Except perhaps to the extent that he knows that the other guy can get someone up there for recon on short notice.) Well, there are tactical issues and there are strategic issues. You've got the tactical right. The strategic you are ignoring. As noted in the other message, that distinction depends partly on who and where you are. Correct. And by controlling who and where the RLVs are, we can mitigate the risks. Consider a world where no RLVs exist and everyone still uses ELVs. Any nation can build an ELV and say they're doing so to become space capable. Its not as clear in this environment that they're building weapons systems. Now, consider a world where ELVs are a technology of the past and everyone's using RLVs. Those who make, maintain, and operate the RLVs, lack the capacity to mass produce the components on a scale needed to create threatening weapons systems. In fact, RLV manufacturers can be controlled in a way that still permits them to operate, but also allows them to demonstrate through inspection and whatnot that their systems are incapable of being converted to long-range missiles. And what happens once they leave the manufacturer's hands? They are licensed and inspected and owned by licensed operators who routinely report to inspection agencies. We want RLVs to ultimately be as common as, say, wide bodied jets. Yes. What stops someone from modifying one of those for some military purpose? (Some wanted the US to use modified 747s as long range cruise missile carriers, rather than develop the B-1, for example.) The same thing that stops airlines from modifying airliners for military purposes. You can't really stop someone from customizing one of these. Why not? I can't modify the exhaust on my convertible beyond a certain range of noise and emissions. That's because my vehicle is licensed and inspected routinely, and I'm licensed to operate it and that is routinely renewed. This makes owning a RLV far different than owning an ELV factory. And if they're willing to clandestinely pre-place nukes (or other weapons) in orbit, it doesn't even take modification. Preventing nukes from being pre-placed in orbit is as easily achieved as preventing nukes from being pre-placed in our cities. Operate the RLVs from disignated launch centers and monitor those launch centers for radiological emissions. Our spaceports will be as secure as our airports - RLVs are another more capable version of wide bodied jets - as you pointed out. Wide bodied jets pose significant risks as we saw. These have been addressed. RLVs pose the same risks - not more. Then you have the added issue of demanding satellite inspection for everyone, when anyone can launch anything on an RLV. Every commercial satellite launched in the US from a US launch center is inspected now. Not so in Korea say. The way to think about this is as follows; In a world of ELVs -the world today- Korea get into the space race by spending a billion dollars on an ELV development. For their money they get a factory to build multi-stage rockets and a launch center. They can do anything they want there, and there are no inspections - and this development poses a significant risk. Since they can defend this investment as an investment in space travel, they confuse the issues about risk to the US and others. In a world of regulated RLVs - the world I propose- Korea gets into the space race by spending a billion dollars on a fleet of RLVs. For their money they get a fleet of proven RLVs operated from approved space ports - and if they sign the appropriate treaties - a space port of their own. They can do anything they want in space - as long as they follow the guidelines of the space agency in charge of regulating space launch. In such an environment, someone who set up an assembly line to produce hundreds of ELVs would have a very hard time of it geopolitically. Mot everyone will care. Mot? Do you mean 'Not'? or 'Most'? They'd be asked what with all the aid and incentives given by the US and its allies, why they chose the ELV route? There would be a very clear sense of international threat and as a result a very high probability of effective action to shut the ELV system down - either through negotation and cooperation - or through decisive limited military intervention - dropping a set of precision guided tungsten KKV rounds from orbit onto the plant. Hmmm...acting pre-emptively has a bad reputation these days. and similary, your intel had better be good. Acting pre-emptively against a space launch builder is difficult. Acting pre-emptively against an unregulated missile factory less so. |
#16
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cheap access to space - majority opinion
william mook wrote:
Joann Evans wrote in message ... william mook wrote: Joann Evans wrote in message ... william mook wrote: This would also help the US contain missile proliferation. If a low-cost RLV of the type described here were operational by a US based firm, it would undercut the rationale others in other nations have (as in Korea) for building an expendable launch vehicle. As a commercial satellite launcher for world markets, yes. Some nations who can't build (or buy) RLVs will still look at ELVs to maintain an independent launching capability, however. Yes, absolutely. But, their motives will be clear to everyone, which will make things easier for our State Department. And of course (espically in Korea's case), they will still want ELVs as medium and long range weapons. But they won't have the fig leaf of space launch development. That's the point. They will clearly be developing weapons systems to threaten us and any coalation that we can assemble who is similarly threatned. Again, this makes things easier geopolitically for the US to contain missile proliferation. The fact that the other guy operates a fleet of RLVs won't affect that. (Except perhaps to the extent that he knows that the other guy can get someone up there for recon on short notice.) Well, there are tactical issues and there are strategic issues. You've got the tactical right. The strategic you are ignoring. As noted in the other message, that distinction depends partly on who and where you are. Correct. And by controlling who and where the RLVs are, we can mitigate the risks. Consider a world where no RLVs exist and everyone still uses ELVs. Any nation can build an ELV and say they're doing so to become space capable. Its not as clear in this environment that they're building weapons systems. Now, consider a world where ELVs are a technology of the past and everyone's using RLVs. Those who make, maintain, and operate the RLVs, lack the capacity to mass produce the components on a scale needed to create threatening weapons systems. In fact, RLV manufacturers can be controlled in a way that still permits them to operate, but also allows them to demonstrate through inspection and whatnot that their systems are incapable of being converted to long-range missiles. Which still does not mean it can't be part of a weapon system. In addition to the example of the 747 as a cruise missle carrier, others have been turned into laser platforms, C-130s have been modified from cargo role, to specialized gunship. Once you sell a flying machine to someone else, the posible modifications are limited only by his technological capability. (Wide bodied jets have also been turned into manned cruise misslies, but that was admittedly a special case.) And what happens once they leave the manufacturer's hands? They are licensed and inspected and owned by licensed operators who routinely report to inspection agencies. Inspection by one's equivalent of the FAA is one thing. By an international agency is another. And an RLV bought and operated by another government (as opposed to a foreign commercial carrier) is yet another. As today, a government, as a matter of policy, may forbid sales to certain nations, but it doesn't mean that manufacturers in other countries can't/won't. We want RLVs to ultimately be as common as, say, wide bodied jets. Yes. What stops someone from modifying one of those for some military purpose? (Some wanted the US to use modified 747s as long range cruise missile carriers, rather than develop the B-1, for example.) The same thing that stops airlines from modifying airliners for military purposes. No profit. But airliners aren't governments. Again, you can currently only be sure of what operators in *your* country are doing. You can't really stop someone from customizing one of these. Why not? I can't modify the exhaust on my convertible beyond a certain range of noise and emissions. That's because my vehicle is licensed and inspected routinely, and I'm licensed to operate it and that is routinely renewed. And this is done by the state you live in, not an international agency. But stock, unmodified cars and trucks have been used in Oklahoma, New York (the first attempt on the WTC) and various places in the Middle East as explosive delivery systems. And that doesn't even consider common-garden non-political smuggling using cars. Thus my example of using unmodified (cargo is cargo) RLVs to pre-place weapons systems of one kind or another in orbit. Not one bolt need be changed between these inspections. This makes owning a RLV far different than owning an ELV factory. If it's built in your country, you knew what it was at the time of delivery, yes. And if they're willing to clandestinely pre-place nukes (or other weapons) in orbit, it doesn't even take modification. Preventing nukes from being pre-placed in orbit is as easily achieved as preventing nukes from being pre-placed in our cities. Operate the RLVs from disignated launch centers and monitor those launch centers for radiological emissions. Hmm. "You may launch from only these locations.' I suspect that's yet more soverignty that many nations will be reluctant to give up. Some because of a hostile adgenda, some just on principle. Our spaceports will be as secure as our airports - RLVs are another more capable version of wide bodied jets - as you pointed out. Wide bodied jets pose significant risks as we saw. These have been addressed. RLVs pose the same risks - not more. Then you have the added issue of demanding satellite inspection for everyone, when anyone can launch anything on an RLV. Every commercial satellite launched in the US from a US launch center is inspected now. Not so in Korea say. The way to think about this is as follows; In a world of ELVs -the world today- Korea get into the space race by spending a billion dollars on an ELV development. For their money they get a factory to build multi-stage rockets and a launch center. They can do anything they want there, and there are no inspections - and this development poses a significant risk. Since they can defend this investment as an investment in space travel, they confuse the issues about risk to the US and others. In a world of regulated RLVs - the world I propose- Korea gets into the space race by spending a billion dollars on a fleet of RLVs. For their money they get a fleet of proven RLVs operated from approved space ports - and if they sign the appropriate treaties - a space port of their own. They can do anything they want in space - as long as they follow the guidelines of the space agency in charge of regulating space launch. In such an environment, someone who set up an assembly line to produce hundreds of ELVs would have a very hard time of it geopolitically. Mot everyone will care. Mot? Do you mean 'Not'? or 'Most'? That should have been 'Not.' They'd be asked what with all the aid and incentives given by the US and its allies, why they chose the ELV route? There would be a very clear sense of international threat and as a result a very high probability of effective action to shut the ELV system down - either through negotation and cooperation - or through decisive limited military intervention - dropping a set of precision guided tungsten KKV rounds from orbit onto the plant. Hmmm...acting pre-emptively has a bad reputation these days. and similary, your intel had better be good. Acting pre-emptively against a space launch builder is difficult. Acting pre-emptively against an unregulated missile factory less so. Locating, and being certain of its purpose can be quite difficult. Irag and Germany (V-2 production) are examples. And there's still the issue of just how much ELV (amateur and small sounding rockets...which might even be reusable) it takes to cross your threshold... -- You know what to remove, to reply.... |
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