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Here we go again with the Dilbert accounting tricks and the "have YOU ever..."'s and now caps-lock & bold screaming about "we have no rights" blah blah blah
..."profitability about the spaceplanes - as the Nuclear type engine assemblies are charged as cargo and thus are charged based on their weight been taking into orbit ( ex fuel ) against other projects plus the costs of pasengers and other cargo onboard both ways the spaceplanes are quite profitable."
Um, what? Accounting tricks aren't going to change the reality of the situation Tristar. Someone will have to pay for those expensive nuclear engines, simply writing them off as "payload" does not make their high cost go away. Ultimatly you will have to charge your customers for the cost of those engines, and since you need a new one every single time you launch, this will raise the cost of every flight dramatically.
It is the low launch cost that makes spaceplanes worth building Tristar, that is their primary reason for being, they are FAR more expensive to construct and develop then conventional rockets, and so the only way that they make financial sense if if the launch price can be held very low. If you have to buy a brand new nuclear engine for every flight, reguardless of its safety or performance issues, then nobody will pay for your spaceplane.
And you say you want to sell the NTR engines when you get up there? If you are flying, say, 150-200 flights per year.. which you would need to support space industrial/research operations you have listed above, that is 150-200 NTR engines you have to find a use for. Since they are so big, you would only need one of them for any concievable payload... but you won't have that many payloads that needs them. And, if your engines are reuseable, then the cargo transfer ships could be reuseable too, so they would need even fewer of your big NTR engines... In short, nobody would buy so many engines, and so you won't get hardly any money for them.
"Have you experimented with the Nuclear Type Engine designs to create new drive systems?"
How typical... I think that you have a fundimental misunderstanding about how experimentation works. When you set up an experiment, you are NOT just blindly playing around and "oh I wonder what happens if...," NO it does not work that way.
Before you do anything, you must have a particular question that you are trying to answer (no "I wonder..."), and you must have some idea of what is going on, so that when you do get your data that you can have a good chance of accuratly interpreting it to answer your question.
Now, I know for fact pretty well what is going on, that you are going to be producing multigram or even kilogram quantities of hyper-radioactive fission decay fragments during the operation of your engine. I know for a fact that that these materials are truely the most deadly poisons in the universe, bar-none, for their sheer killing power. And I know that you will be carrying these decay fragments in a flimsy metal tin can that is just short of melting or exploding, which it being carried over all our heads in a hypersonic derigible that could crash any time, anywhere and no light-weight armor could ensure containment.
I do not need to experiment to tell me that this is a problem, because I know that these materials are extremely deadly, so the only possible answers to the safety question are all "not safe." No experiment concerning the safety of NTR engines is nessesarry, and since chemical engines can do the same job as your NTR engine can, and they can do cheaper, and they don't have this risk problem... Then the ultimate question, chemical or nuclear, is already answerd.
I also know a little bit about rockets, and one of these concepts is the idea of a thrust-to-weight ratio. If your spaceplane has a low thrust/weight ratio, then it will have a difficult time flying because you must use so much fuel just keeping you from falling down again. Since you will need to use your engine mostly out of the atmosphere, you won't have any lift to help you here either. The old NERVA engines were quite heavy compared to the thrust they produced, and that isn't counting the radiation shield or reentry armor or the extra tank mass & drag.
This adds up to tell me that your engine will not provide you radically superior performance compared to chemical engines because of all these problems it has. From a pure performance standpoint, I don't really need to do any simulations of exactly how much weight your engine would save/add because we already know the range of possible answers well enough to estimate that the bennefits are limited. Because NTR rockets are only about twice as efficent but all the extra mass (reactor, shielding, tanks, etc) will easily eliminate these bennefits.
If the reactor weighs around ten or fifteen tonnes (most large NERVA engines topped 20MT), its radiation shield another few tonnes, the extra fuel tanks another ten tonnes more, and you haven't even gotten to the crash armor yet... It is clear to me that the bennefits obviously do not overcome the fatal expense of not reuseing the engines and certainly doesn't overcome the risk of catastrophy.
Either you overcome these fundimental problems, or your plane doesn't fly. Period.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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I'm just going to jump in here with a question.
Large NTR engines would be expensive to develop and build, while reuseable H2/O2 engines are being developed right now
I didn't know anyone was pursuing reuseable engines any more, that any advances would be incremental in nature and would not be worth the effort.
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Some where back in this discusion we talked about enginge out capability for if an engine malfunctions.
Has any one else that that it also causes less fatigue on the engines, could allow for longer firing times and in addition if pushed to capabilities of the ratings allow for larger cargo to be launched.
As for Nuclear engines being not for launch I would say agreed and that once in orbit only shielding remains as a problem for a human carrier. As for reusability that's a plus if maintenance costs are very low for each reuse.
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No reuseable engines? http://www.pratt-whitney.com/prod_space … _cobra.asp
I think this would do the trick... able to handle the requisit 50 flights before overhaul, and excelent reliability. At least some componets of it have been test fired.
http://www.pratt-whitney.com/prod_space … ce_rlx.asp
Not sure about the fate of the RLX project, which may have gone out with SLI. It would also serve well for the application.
And make a reuseable version of this, http://www.space.com/businesstechnology … ...-1.html
Able to withstand at least 25 flights, and we'd be in business.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Thanks GC. There is so much to learn here. It took the free time I had and a couple of days to just to read the heavy lift topic and some of the links. Then I was chasing the new shuttle topic. And because I was born so long ago, I won't remember half of it.
So that cobra engine, the engine
My questions would drag this off topic, even though they may pertain to the shuttle. The cobra looks near heavy lift and I'm going over there.
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The COBRA engine wouldn't be suitable for heavy-lift applications, because it will be quite expensive per-copy. The Boeing RS-68 is much better suited hydrogen engine for heavy lift because it is so cheap, you can afford to throw it away.
COBRA is a specialty engine, and is what the SSME should have been when it was concieved. It would be perfect for a new spaceplane upper stage.
Then all we'd need is a reuseable kerosene rocket for the lower stage or a modernized jet/ramjet combination engine, perhaps with LOX augmentation to squeeze out that last mach number.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Question,
Lox augmentation, Do you mean to have Oxygen put into the airstream to cool and so condense the air stream ENTERING the engine or to have the engine burn it as well as kerosene. But we can use water for the same purpose so cooling the air entering the engine allowing increased thrust
Still I think if we where to have installed the tankage for storing either water or LOX it really would then make sense to have a rocket engine to provide the thrust after taking over from normal jets.
less needing of a new engine then.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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I mean inject liquid oxygen to accelerate combustion and raise the maximum altitude the engine can operate at. NASA experimented with the idea a little already, taking an engine from an F-15 fighter jet and spraying LOX into the compressor. In theory, the engine would still operate efficently up to around Mach-4 to Mach-5.
Worth looking into... Combine this technology with Ramjet engines, and perhaps reach Mach-6 and radically increase operating altitude such that both vehicles become much smaller.
I like the idea of using a jet engine becuse they are naturally more reuseable, the less time you spend on the ground servicing them the better, and much more efficent then rocket engines (because they need not carry all their reaction mass). If you could make them reliable enough, you could even have one carrier plane serve two or three spaceplanes, which will cut down the fleet size dramatically.
If a rocket engine is used, you'll need a new one of those anyway. Since the size of the lower stage is important to limit but not the specific impulse, you would naturally turn to Kerosene rocket engines. At the moment, no large reuseable kerosene engine exsists or is being developed as far as I know. And you'd have to lug along quite a bit of fuel for those engines, and their ~10MT/each mass.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Martian Republic,
Then I agree with your assessment of the issue it is dead to most you, that we can not find a proper transportation system for large scale movement of personnel and cargo into orbit. If we use the current modes of transport to orbit then we are just WE ARE TOURISTS AND HAVE NO RIGHT TO DICTATE SOLAR SYSTEM POLICIES.
Our organization hasn't got the huge resources yet, to bring us into the space transportation sector yet, but at least we are working towards goals that have better success for long term space research, training, and infrastructure for the future in private enterprise large scale space activities.
Infrastructure means - space vessel construction, communications, navigation, life sciences, colonizations techniques, social interactions, and more.
I'm not against building large transports or next generation shuttle. But you have to take a logical approach to build the next generation should. You also have to have a need for a large capacity shuttle too or your just spending money and not getting any return on it.
I like big projects too. But, I also know what it takes to accomplish those big projects. I have bounced the idea of building a city on Mars of a hundred thousand People several times in a forty to fifty year time frame. But, even I understand that in the economic system that is impossible to do. For the United States to be able to do that. We would have to have a National Space Goal to build that city on Mars and we would have to Nationalize the Federal Reserve System to do that. The reason that we would have to do both those things is: Without a National Goal, we would have no staying power to build that city on Mars. Without Nationalizing the Federal Reserve System and either putting it under the Treasury Department or setting up a Third National Banking System that run by the US Government, the US Government would not be able to come up with the money to build that city on Mars. Unless both those things happen, then build a City on Mars is impossible. Because, building that city on Mars will cost trillions of dollars, because you have to develop technology and you have to build the infrastructure to do that. It will take at least two generations to do that, because of the mass of new technologies you have to develop and the infrastructure you have to build and you can't do that on a shoe string budget like what you got. It just not going to happen. Like it would take the US Government forty or fifty years to do it with the power to America behind it and have control over there own banking system or the US Government could not do it either.
Larry,
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Martian Republic,
The main issue that people have in developing new spaceplanes or any other developments that require large resource allocations is that the creation of cash reserves to do it. We need to look at the valuation of space-based resources and then loan against those resources for construction of large infrastructure.
You are right that a single country on earth properly won't have the resources to use exclusively for the development of space eg. US$100 Billion per year for 50 years = US$5 trillion dollars in infrastructure and operational costs. That might be enough to get up to critical mass outside earth and thus the exploration and settlement could fund its on expansion without needing the earth's resources.
But then it comes down to alot of legal factors that have been discussed before. The most important requirements are the creation of a lunar office within the united nations and a mars office within the united nations and two separate councils be created to oversee the development of both locations out of the control of the any one government. But that won't happen and the development of spaceplanes, larger spacecrafts then will need a different answer , and might require a consortium of private interests and a long term vision and supporting the infrastructure through exisitng business interests globally.
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Martian Republic,
The main issue that people have in developing new spaceplanes or any other developments that require large resource allocations is that the creation of cash reserves to do it. We need to look at the valuation of space-based resources and then loan against those resources for construction of large infrastructure.
You are right that a single country on earth properly won't have the resources to use exclusively for the development of space eg. US$100 Billion per year for 50 years = US$5 trillion dollars in infrastructure and operational costs. That might be enough to get up to critical mass outside earth and thus the exploration and settlement could fund its on expansion without needing the earth's resources.
But then it comes down to alot of legal factors that have been discussed before. The most important requirements are the creation of a lunar office within the united nations and a mars office within the united nations and two separate councils be created to oversee the development of both locations out of the control of the any one government. But that won't happen and the development of spaceplanes, larger spacecrafts then will need a different answer , and might require a consortium of private interests and a long term vision and supporting the infrastructure through exisitng business interests globally.
I believe the Important thing if we want to have major industrial and infrastructure in space is to have a workable and fair treaty that allows use of resources and defensibly legal property claims or rights to free use of such.
If we involve the UN it will simply increase the red tape that any pioneering country will have to face to be able to use and utilise the materials found in space. Or worse it simply becomes a free for all with no country giving any regard to any other country. And it comes down to gunboat diplomacy.
But if we can reduce costs to orbit then so all other prices for space come down and that is why we are looking at spaceplanes. They might not be able to launch anything like the cargo that a medium to heavy lift rocket can do but they can send there cargoes up a lot lot cheaper simply through constant reuse.
It only takes a real good incentive for a country to develop spaceplanes and at the moment there is not one. But this can change.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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Grypd,
I think it would the best way to push the issue to ahead is to let competing forces get access to the resources in space and it will make them form alliances and eventually work together, and those who don't will perish from the universe , " its a destructive place and a place of beauty. "
That means spaceplanes and different engine designs, and even Mars plans could compete against each other for development and resource allocation.
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Grypd,
I think it would the best way to push the issue to ahead is to let competing forces get access to the resources in space and it will make them form alliances and eventually work together, and those who don't will perish from the universe , " its a destructive place and a place of beauty. "
That means spaceplanes and different engine designs, and even Mars plans could compete against each other for development and resource allocation.
One of the most destructive treaties to what we could have called a frontier was "the law of the sea". This treaty destroyed undersea mining and pretty much put to a stop the grand plans for cities under the sea or any big advance in manned prescence in the Oceans.
It did this by simple means.
The UN is in charge of the oceans period any company must pay the UN a fee to be able to operate on the ocean floor. And in the future this will also include large vessels crossing the Ocean.
Any country that has a shore in which you operate is entitled to a share of what you gain from the sea shore. And no country may claim resources that are 200 metres below the surface and all resources are the heritage of mankind. What this basically means is dont touch unless you can afford to pay the fees and you really desperatly need those resources.
Why do I tell this as it is basically how the UN and many nations amongst it want us to treat space. Any law of space and the outer space treaty is just such an example of a great hindrance to space utilisation.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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grypd,
I mean market forces, and whoever gets there can claim it. No treaty !!!!!
Because all governments are two faced and they only keep their word until they want to take control. So, If America (itself) or a group lead by America should claim their part and hold it or the others can do the same and private enterprise can do the same.
Because No-one will agree about the treaties and guarantee that entreprenuers won't be asked to sign treaties, So the best method is what runs on earth , America top of the pile, they will need to be the top of the pile in space or someone else will !!!!!!!!!!!!!.
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grypd,
I mean market forces, and whoever gets there can claim it. No treaty !!!!!
Because all governments are two faced and they only keep their word until they want to take control. So, If America (itself) or a group lead by America should claim their part and hold it or the others can do the same and private enterprise can do the same.
Because No-one will agree about the treaties and guarantee that entreprenuers won't be asked to sign treaties, So the best method is what runs on earth , America top of the pile, they will need to be the top of the pile in space or someone else will !!!!!!!!!!!!!.
But unfortunatly in the Moon treaty it clearly states that a country takes responsibility for any flight that is launched by citizens of that country. And that means that the treaty so applies too those people. So frankly unless the Moon treaties very negative sections that deal with owning extra terrestial property are dealt with there is no chance under international law that we will get away with declaring ownership of any property or right to utilise those resources for anyhting except exploration and aiding in such.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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Grypd,
Not all people are covered under that treaty only countries that sign the treaty and only the member states that have signed. !!!!!!!!!!
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Martian Republic,
The main issue that people have in developing new spaceplanes or any other developments that require large resource allocations is that the creation of cash reserves to do it. We need to look at the valuation of space-based resources and then loan against those resources for construction of large infrastructure.
You are right that a single country on earth properly won't have the resources to use exclusively for the development of space eg. US$100 Billion per year for 50 years = US$5 trillion dollars in infrastructure and operational costs. That might be enough to get up to critical mass outside earth and thus the exploration and settlement could fund its on expansion without needing the earth's resources.
But then it comes down to alot of legal factors that have been discussed before. The most important requirements are the creation of a lunar office within the united nations and a mars office within the united nations and two separate councils be created to oversee the development of both locations out of the control of the any one government. But that won't happen and the development of spaceplanes, larger spacecrafts then will need a different answer , and might require a consortium of private interests and a long term vision and supporting the infrastructure through exisitng business interests globally.
But, I would like the United States to put the Federal Reserve into bankruptcy and reorganized into either a Third National Bank or put under the Treasury Department, before the eminent economic collapse of the US Economy like the 1929 Stock Market Crash.
Then the US Government will have to restart the US economy and the only way they can do that is by generating credit internally from either the Treasury Department of the Third National Bank the way that FDR did. Now initially we will have to have between one to two trillion dollars or so of new credit to start off with and an additional five hundred billion to one trillion dollars of new credit there after to keep the economy going. Since the US Government is going to be the one generating that new credit instead of some private bank called the Federal Reserve System, the US Government will be the one directing where that new credit going to be going. If we just direct 10% of that new credit being generated to NASA and a new National Space Goal like that of John F. Kennedy for say fifty years or so. Now the other 90% of that credit will be spent down here building levitated trains, nuclear power plants, FDR river dams and power plant programs, subways systems, NAWAPA, etc. That will be how these massive space projects will be funded and how we will build those massive infrastructural projects. We would have to have somebody like John F. Kennedy as President of the United States to say that we have a national mission to build a city on Mars in a forty to fifty year time frame and then tip it to NASA and have them work on the problem. Once you know what you want to accomplish, then you know what you have to develop to accomplish your new mission that was put forth by the President of the United States. Any serious or large scale space project, mission or colonization will have to come from this direction, because this is the only way that it could be financed and built.
Private Enterprise in space would spring from these roots and it would be profitable for Private Enterprise in space to function and develop only under these conditions.
I have gotten into argument with other people about how private enterprise can not develop or colonize space by themselves. It just not going to happen. Some one will say what about the tourist industry? We could make million of dollars from rich people as tourist in space. But, it going to cost billions to develop shuttle that can reach the ISS station and that only a small part of the problem that we need to address. Then someone will say, we will put a hotel on the moon, although it may be a little Spartan though. It will cost 50 to maybe 200 billion dollars to build a Spartan hotel on the moon. For another 50 to 100 million dollar you can doll it up like the hotels here on the Earth. They think maybe some how saving 50 to 100 million will either build the infrastructure that needs to be there at an affordable level and will some how make that 50 to 200 billion or more acceptable minus that 50 to 100 million for price of carpet and other such things. The point is, that the tourist industry is never going to pay for the price of developing any thing in space when you only are getting back 2% or 3% of what it cost to make it in the first place.
The market forces are not going to drive a space economy either and neither will mining or manufacturing in space or immigration into space drive a space economy either. Even if you could setup a mining colony in space. One question! Who are you going to sell your ore to if there no one in space? Who going to refine that ore into metal to be use by colonist? To build a colony of sufficient size that could make your mined ore valuable would be expensive? Because, it going to cost you hundreds of billion to maybe trillions of dollars to build that colony in space or the moon or Mars. The building of that colony will have to be done at a loss, so your mining venture may be able to make a profit. It doesn't matter how your figuring it, what you need to do to make a profit in space on a large scale in space will come up short in the hundreds of billion of dollar range. Unless you can deal with these problems, you grandiose vision of the future will go nowhere. Your plans are based on a fulty economic system that does not work and can not work and will never work and under no circumstance could it ever work.
I know a government under the leadership of Abe Lincoln, FDR, John F Kennedy had done in the past. Under the leadership of Abe Lincoln we built the transcontinental Rail Road, became an industrial Nation, developed electricity and other new inventions. Under the leadership of FDR, Dams rural electrification, roads, Social Security, Medicaid & Medicare, etc. Under leadership John F. Kennedy, we went to the Moon. Under a new President of the United States, we need to re-industrialize the United States and we need an FDR type programs to rebuild American, because it is collapsing into disrepair. The bridges are falling down, the sewer and water system are old and falling apart, etc.
However I can show you a history of the real American Economic System that has worked when ever we apply the principle that are written in the US Constitution. These Economic principle worked for Alexander Hamilton, Abe Lincoln, FDR, John F. Kennedy. If I could direct the US Government, those same principle will work for me too.
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"But, I would like the United States to put the Federal Reserve into bankruptcy...
...I can show you a history of the real American Economic System that has worked when ever we apply the principle that are written in the US Constitution. These Economic principle worked for Alexander Hamilton, Abe Lincoln, FDR, John F. Kennedy. If I could direct the US Government, those same principle will work for me too."
Translation: Blah blah insane conspiracy theory blah blah I hate George W Bush blah blah state-suicide via credit collapse blah blah beliefe in gov't credit is an endless money maker blah blah outrageous price figures blah blah rediculous long-term goal setting blah blah more conspiracy about secret impending economic catastrophy blah blah stupid beliefe in anticent economic systems working today blah blah LaRouche-like delusions of grandeur...
And all that other fun stuff, which belongs in other threads, that we have heard countless times from MR.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Grypd,
Not all people are covered under that treaty only countries that sign the treaty and only the member states that have signed. !!!!!!!!!!
Ah but in the case of the Moon treaty there is very few states that have not ratified it and those are so small it really does not matter. The Moon treaty and its legal standings can rightfully be said to be applied to all countries.
But it was a treaty designed to stop a land grab race between the USSR and the USA which could have lead to real tensions and the other parts like a spaceship remains the property of the country that launched it and free access to any space endeavour are just to stop potential trouble. But for private access and use it is a big hindrance and pretty much is putting a stop to any real plans. As those companies and private organisations will simply be treated under the treaty as extensions of that country and therefore requiring to obey the treaty.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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I cannot believe we are going to design another Toy for the
Top Gun set at NASA. Two Crew have to be dedicated to
just Pilots on the Shuttle. That's 28% of your Human Wetware that becomes useless during the Mission itself.
Think about the extra hardware a Shuttle needs so it
can function as a reuseable craft.
Landing Gear Assembly. Actuator Motors for control surfaces. Double occupancy Cockpit. Extra large windows. Large
Surface Area Reentry Thermal tiling.
Unless we are talking about a Scramjet aircraft that severely lowers the cost of LOE I see no reason to make your new spacecraft reuseable. Reusabilty is a gimmick intended to justify "space plane" technology, and simply a jobs program
for the contractors.
How can this be true?
Because taking apart a man rated craft after it has flown and
refurbishing it and recertifying for use is acutally much more
expensive than building expendable throw away Assebly line
spacecraft. The Shuttle is the proof of this.
It is far better to go with an modenized Apollo Command module adapted to hold 6 crew and 1 pilot. If you need a larger Mission Ship. Just have larger module dock with the CM nose to nose. (obviously a small LOE Retro-Maneuver module
would be required also)
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I cannot believe we are going to design another Toy for the
Top Gun set at NASA. Two Crew have to be dedicated to
just Pilots on the Shuttle. That's 28% of your Human Wetware that becomes useless during the Mission itself.Think about the extra hardware a Shuttle needs so it
can function as a reuseable craft.Landing Gear Assembly. Actuator Motors for control surfaces. Double occupancy Cockpit. Extra large windows. Large
Surface Area Reentry Thermal tiling.
Unless we are talking about a Scramjet aircraft that severely lowers the cost of LOE I see no reason to make your new spacecraft reuseable. Reusabilty is a gimmick intended to justify "space plane" technology, and simply a jobs program
for the contractors.How can this be true?
Because taking apart a man rated craft after it has flown and
refurbishing it and recertifying for use is acutally much more
expensive than building expendable throw away Assebly line
spacecraft. The Shuttle is the proof of this.It is far better to go with an modenized Apollo Command module adapted to hold 6 crew and 1 pilot. If you need a larger Mission Ship. Just have larger module dock with the CM nose to nose. (obviously a small LOE Retro-Maneuver module
would be required also)
Indeed but if you can reuse these parts time and time again then there actual cost reduces as they are only intial outlay. When it comes to CEV it means you will spend a few million to purchase the one shot capsule and heatshield. If we can develop a TSTO then as it is used more and more it will overtake a CEV design.
But as for crew being put down as useless thats a load of ####. In a mission on the shuttle these crew also are quoted as doing there other specialities and can frankly be classed as scientist/mission technicians first and as pilots second.
We have already shown that the Shuttle was a disaster from a financial sense as its particular design was so flawed and it flew so little and needed so much in ground support. But one of its worst problems was it was to be the be all and end all. It had to carry cargo at the same time as crew and it did neither well. It weighs almost 105 tons and this is all fired up and returned. the TSTOs that are planned here are a lot smaller and are dedicated to a specific purpose either cargo with no crew on board at all and manned which is just that a pure passenger load. It also reuses all other items ie the lower stage is reused and as it does not leave the atmosphere and will likely be a jet powered plane can simply be quickly reused so reducing cost.
And it is the amount of flights that means actually how expensive a flight is. Look at how airlines are able to keep airplane tickets down just by constant flights.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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I cannot believe we are going to design another Toy for the
Top Gun set at NASA.
We aren't building a spaceplane right now, nor in the nearish future, but not because of the reasons you have cited.
If you had more then single-digit numbers of neurons in your head and have been reading the actual posts in the thread, you would have learned that a spaceplane is only a good idea if it can be flown repeatedly.
It is quite possible to build a real spaceplane that can withstand multiple flights (I am aiming for 25) that does not need refurbishing between them. Modern technology is a generation beyond what Shuttle was built with, and we can today build rocket engines, heat shields, and other equipment that are up to the task.
Yes a Shuttle-II would be expensive to develop (at least $15Bn), no doubt about it. They will also be very expensive (I would estimate as high as 15X-20X a comperable launcher) to build even if development were free. No argument there...
...but if the spaceplane can fly several hundred times for under a fifth of the cost of an expendable rocket each, then the spaceplane has rockets beat cold.
The Space Shuttle of today was a disaster, no question about that, a debacle of terrible proportions. Why? Because it was supposed to make too many people happy. Make NASA happy with it being reuseable and carry intermediate payloads (~40MT), make the USAF happy with single-orbit polar trajectories (big wings, lots of lift, heavier), and the accountants happy (small development and flight costs, which are mutually exclusive)... Shuttle could have only done only one of these things, but NASA was stupid and tried to do all three with technology that wasn't good enough.
And so, here we are.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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As a general point be careful when someone says
reusable is cost efficient in manned programs. I know we
only have one example, the worst type at that.
Even a simpler proceedure such as Shuttle SRB recyclying
is a logistical headache.
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A little bell rang loudly about a thread that some what matched the content of this article [url=http://www.msnbc.msn.com/id/11691989/]Did Pentagon create orbital space plane?
Magazine reports evidence for classified project, sparking some skepticism[/url]
Followint the links lead to a more coplete article [url=http://www.aviationnow.com/avnow/news/channel_awst_story.jsp?id=news/030606p1.xml]
Two-Stage-to-Orbit 'Blackstar' System Shelved at Groom Lake?[/url]
One Pentagon official suggests that the Blackstar system was "owned" and operated by a team of aerospace contractors, ensuring government leaders' plausible deniability. When asked about the system, they could honestly say, "we don't have anything like that."
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A fly-boy's play toy. Delta II could probably orbit more.
Please...
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