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On 29 Dec, 13:59, "Martha Adams" wrote:
"Leopold Stotch" wrote in message news:kVX5l.500909$yE1.187414@attbi_s21... kT wrote The foam problems still remain as the fundamental engineering science of rocket science, something America has abandoned with Michael Griffin. The "foam problem" is only a problem when you mount the crew vehicle in tandem with the booster the way the STS does. *Put the crew vehicle on the top and shed foam till the cows come home, who cares? *So long as there is nothing important to hit foam shedding is not an issue. Hell, put the CV on top and forget about putting foam on the thing at all. I think there's a major problem here, about *what is* good engineering? As I look at today's industrial base for getting out to space, seems to me it has largely degenerated into a business of getting money. *Like medicine, in recent decades. *If you then bring in the military, maybe you see reasons for heaving a great lumpy airframe up into space rather than simpler up-and-maybe-return vehicles. *The airframe yields much greater cross-range capability, a military value. *So it turned out sending out airframes was harder to do than expected in advance and apparently less rewarding, and here we are today. As I think Iimplied in a previous posting the main problem is reentry. If you can go from LEO to the ground WITHOUT ablation you have potentially a solution. If you put ablative tiles on the underside of your airframe you might just as well have a capsule as the kinetic theory of gases tells us that less will be ablated for a steep reentry. If you can manage an airframe where refactory materials are in thermal equilibrium and the airframe can reenter indefinitely you will have succeeded in reducing costs. There was NEVER any point in having a Shuttle with tiles. A capsule would have done the job a lot better. True the Shuttle has cross range. A capsule has no cross range. Since when has cross range been of such critical importance? The military have never in fact made use of that capability. Only two airfields have ever handled a Shuttle. Cape Canaveral and Edwards. With all those people and institutions boiling around the space business, could someone step back from the mess and develop a history of it? *I'd like to see that. *And I view Elon Musk's SpaceX with considerable hope, but how soon will Big Money and Big Military step in and take it over? *With what consequences in this violent universe to our human future? The military does not want turkeys. In fact it could be said that it was the military who killed the Shuttle when they saw it for what it was. In my view, we need some people to step out and affirm, the reason for going out to space is it's where the future is. *The best outline of this that I have seen is Frederick Jackson Turner's paper in 1893 about the frontier in America's development. *If you know something about today's space technology and about what was thrown away when Apollo was killed, you can translate Turner's paper from what he wrote in the late 1800's into a very plausible outline of a possible future to come. *And I believe that future is almost sure to happen, but I'm not so sure its base will be American. With costs as they are I thing that only an international grouping can explore space. However you look at it the way to reduce costs is to rationalize. There are those whio advocate new technology - like trult recoverable winged vehicles. There are those, like myself who are more skeptical. Those who want new technology must be aware that it is going to be expensive to develop. This thread and also "Steve Linsey astronaut liar" bear this out. NASA simply cannot spend billions and billions on every possibility. If you want cheaper expendible rockets again rationalisation + a larger market is the answer. The USA has great difficulties in engaging in collaborative projects. Eventually it willl have to do do. It won't like not having all the decisions not going its way. - Ian Parker |
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On Tue, 30 Dec 2008 06:21:00 -0800 (PST), Ian Parker
wrote: (snip) True the Shuttle has cross range. A capsule has no cross range. Unless it's built with its center of gravity offset from the centerline of the capsule... Since when has cross range been of such critical importance? The military have never in fact made use of that capability. Only two airfields have ever handled a Shuttle. Cape Canaveral and Edwards. Three. They landed at White Sands at least once. take care, Scott |
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"Ian Parker" wrote in message ... On 29 Dec, 13:59, "Martha Adams" wrote: "Leopold Stotch" wrote in message news:kVX5l.500909$yE1.187414@attbi_s21... kT wrote The foam problems still remain as the fundamental engineering science of rocket science, something America has abandoned with Michael Griffin. The "foam problem" is only a problem when you mount the crew vehicle in tandem with the booster the way the STS does. Put the crew vehicle on the top and shed foam till the cows come home, who cares? So long as there is nothing important to hit foam shedding is not an issue. Hell, put the CV on top and forget about putting foam on the thing at all. I think there's a major problem here, about *what is* good engineering? As I look at today's industrial base for getting out to space, seems to me it has largely degenerated into a business of getting money. Like medicine, in recent decades. If you then bring in the military, maybe you see reasons for heaving a great lumpy airframe up into space rather than simpler up-and-maybe-return vehicles. The airframe yields much greater cross-range capability, a military value. So it turned out sending out airframes was harder to do than expected in advance and apparently less rewarding, and here we are today. As I think Iimplied in a previous posting the main problem is reentry. If you can go from LEO to the ground WITHOUT ablation you have potentially a solution. If you put ablative tiles on the underside of your airframe you might just as well have a capsule as the kinetic theory of gases tells us that less will be ablated for a steep reentry. If you can manage an airframe where refactory materials are in thermal equilibrium and the airframe can reenter indefinitely you will have succeeded in reducing costs. There was NEVER any point in having a Shuttle with tiles. A capsule would have done the job a lot better. True the Shuttle has cross range. A capsule has no cross range. Since when has cross range been of such critical importance? The military have never in fact made use of that capability. Only two airfields have ever handled a Shuttle. Cape Canaveral and Edwards. With all those people and institutions boiling around the space business, could someone step back from the mess and develop a history of it? I'd like to see that. And I view Elon Musk's SpaceX with considerable hope, but how soon will Big Money and Big Military step in and take it over? With what consequences in this violent universe to our human future? The military does not want turkeys. In fact it could be said that it was the military who killed the Shuttle when they saw it for what it was. In my view, we need some people to step out and affirm, the reason for going out to space is it's where the future is. The best outline of this that I have seen is Frederick Jackson Turner's paper in 1893 about the frontier in America's development. If you know something about today's space technology and about what was thrown away when Apollo was killed, you can translate Turner's paper from what he wrote in the late 1800's into a very plausible outline of a possible future to come. And I believe that future is almost sure to happen, but I'm not so sure its base will be American. With costs as they are I thing that only an international grouping can explore space. However you look at it the way to reduce costs is to rationalize. There are those whio advocate new technology - like trult recoverable winged vehicles. There are those, like myself who are more skeptical. Those who want new technology must be aware that it is going to be expensive to develop. This thread and also "Steve Linsey astronaut liar" bear this out. NASA simply cannot spend billions and billions on every possibility. If you want cheaper expendible rockets again rationalisation + a larger market is the answer. The USA has great difficulties in engaging in collaborative projects. Eventually it willl have to do do. It won't like not having all the decisions not going its way. - Ian Parker ========================================== Parker says, "With costs as they are I think that only an international grouping can explore space." Is this realistic thinking? I haven't the numbers in hand, however, I expect that if we compare the costs of the most recent American wars vs the cost of space, each less estimated value of their returns to America, then one can argue that if America can afford those wars, it can afford space ten times over. Thus no need for collaboration with other countries to cover those costs. Which would be, over the long run, a large net advantage since international ownership issues could not arise. So *how does* space cost so much only international grouping can pay it? Looking at this from another direction, under recent Republican administration, America has slipped down badly in this world. A recent book title, "Are We Rome?" is much too relevant right now. Space with its immense capacity to change and growth, like America was in the 1500s and 1600s, offers a way to change and recover from this. *If* we don't get tangled up in bureaucratic issues such as contractual obligations to other countries. Titeotwawki -- mha [sci.space.policy 2008 Dec 30] |
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x"Leopold Stotch" wrote in message
news:kVX5l.500909$yE1.187414@attbi_s21... kT wrote The foam problems still remain as the fundamental engineering science of rocket science, something America has abandoned with Michael Griffin. The "foam problem" is only a problem when you mount the crew vehicle in tandem with the booster the way the STS does. That's certainly a huge issue, but not the only one. There's still the concern about foam and ice hitting the engine area. Put the crew vehicle on the top and shed foam till the cows come home, who cares? So long as there is nothing important to hit foam shedding is not an issue. Hell, put the CV on top and forget about putting foam on the thing at all. Only if you want to have even more problems. You need to insulate the tanks. |
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"Ian Parker" wrote in message
... True the Shuttle has cross range. A capsule has no cross range. Since when has cross range been of such critical importance? The military have never in fact made use of that capability. Only two airfields have ever handled a Shuttle. Cape Canaveral and Edwards. You might want to check your facts. As Jorge has pointed out, the cross-range capabilities have been used quite a lot in planning de-orbit ops. It opens up more times you can de-orbit. -- Greg Moore Ask me about lily, an RPI based CMC. |
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"Greg D. Moore (Strider)" wrote in message ... "Ian Parker" wrote in message ... True the Shuttle has cross range. A capsule has no cross range. Since when has cross range been of such critical importance? The military have never in fact made use of that capability. Only two airfields have ever handled a Shuttle. Cape Canaveral and Edwards. You might want to check your facts. As Jorge has pointed out, the cross-range capabilities have been used quite a lot in planning de-orbit ops. It opens up more times you can de-orbit. True, but part of the reason it's good for the shuttle is because of all the other constraints on a shuttle landing. For example, it can't land in rain or with high cross-winds. How many times has a shuttle landing been delayed or diverted by weather? I think what you need to look at is the overall ability of the new vehicle to land in a timely manner. The details, such as cross-range and ability to land in poor weather conditions, are just that, details. Furthermore, when you're talking about returning from the moon, the ability to land at more than two locations (KSC and Edwards) is a good thing. Also, resistance to bad weather during landing is more important, since you're committed to a landing time when you leave lunar orbit and weather has much more time to turn bad in that situation than after a de-orbit burn in LEO. Jeff -- "Many things that were acceptable in 1958 are no longer acceptable today. My own standards have changed too." -- Freeman Dyson |
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On 30 Dec, 15:28, "Martha Adams" wrote:
"With costs as they are I think that only an international grouping can explore space." Is this realistic thinking? *I haven't the numbers in hand, however, I expect that if we compare the costs of the most recent American wars vs the cost of space, each less estimated value of their returns to America, then one can argue that if America can afford those wars, it can afford space ten times over. I think there is a difference. Don't get me wrong. I have campaigned consistently against Iraq. Have been called names for so doing. Arrogance has compounded the folly. I believe that money should be spent on "curiosity" how much though? Science has always been international. Papers have been available for everyone to read. Way way back Isaac Newton wrote in Latin to make his work available to the widest possible readership. Everyone in those days could read Latin, now very few can. I believe it is realistic, particularly when we remember that Soyuz now flies from Kourou. Thus no need for collaboration with other countries to cover those costs. *Which would be, over the long run, a large net advantage since international ownership issues could not arise. *So *how does* space cost so much only international grouping can pay it? This depends on how you manage it. If you let each country have a say in every project then what you say is right. If on the other hand you let each country do what it is best at you then have a basis. Looking at this from another direction, under recent Republican administration, America has slipped down badly in this world. *A recent book title, "Are We Rome?" is much too relevant right now. *Space with its immense capacity to change and growth, like America was in the 1500s and 1600s, offers a way to change and recover from this. **If* we don't get tangled up in bureaucratic issues such as contractual obligations to other countries. America has indeed slipped down the international science rankings. America is biased to training lawyers. The reasons for this are complex. The Far East on the other has put an absolute priority on producing graduates in Science and Engineering. They say Chinese rockets are becoming more reliable. Basically people do not go into Science and Engineering because the perceived rewards are far higher elsewhere. Intelligent Design does not in itself secure a dearth of scientists, but the failure to listen to science, indeed the failure to listen to trained intelligence speaks volumes. Getting back to Iraq, people were chosen for the CPA not on any ability to do the job but on their evangelical credentials. I don't think anyone could speak Arabic. If this gets round people will not want to study Arabic, or Science for that matter. If you have a free enterprise commercial environment there is no reason why there should be bureaucratic tangles. What you do is the following. Say you want SSP. You put out a contract to lift 10,000 tons to GEO. X has a robot. X says no I can mine asteroids and I can give you 15,000 tons of Al foil sourced from asteroids. Do you accept my bid? The USA has always viewed space in nationalistic terms. This sort of thinking will have to cease. They do not have any prestige. It is hard to get prestige if the World's engineers are all in the Far East. - Ian Parker |
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Ian Parker wrote:
:On 29 Dec, 13:59, "Martha Adams" wrote: : "Leopold Stotch" wrote in message : : news:kVX5l.500909$yE1.187414@attbi_s21... : : kT wrote : : The foam problems still remain as the fundamental engineering science : of rocket science, something America has abandoned with Michael : Griffin. : : The "foam problem" is only a problem when you mount the crew vehicle : in tandem with the booster the way the STS does. *Put the crew vehicle : on the top and shed foam till the cows come home, who cares? *So long : as there is nothing important to hit foam shedding is not an issue. : Hell, put the CV on top and forget about putting foam on the thing at : all. : : I think there's a major problem here, about *what is* good engineering? : As I look at today's industrial base for getting out to space, seems to : me it has largely degenerated into a business of getting money. *Like : medicine, in recent decades. *If you then bring in the military, maybe : you see reasons for heaving a great lumpy airframe up into space rather : than simpler up-and-maybe-return vehicles. *The airframe yields much : greater cross-range capability, a military value. *So it turned out : sending out airframes was harder to do than expected in advance and : apparently less rewarding, and here we are today. : :As I think Iimplied in a previous posting the main problem is reentry. :If you can go from LEO to the ground WITHOUT ablation you have otentially a solution. If you put ablative tiles on the underside of :your airframe you might just as well have a capsule as the kinetic :theory of gases tells us that less will be ablated for a steep :reentry. : :If you can manage an airframe where refactory materials are in thermal :equilibrium and the airframe can reenter indefinitely you will have :succeeded in reducing costs. There was NEVER any point in having a :Shuttle with tiles. A capsule would have done the job a lot better. : You seem to think the tiles on the Shuttle are ablative protection. They're not. Hence, by your own implication, the shuttle must be "potentially a solution". -- "Ignorance is preferable to error, and he is less remote from the truth who believes nothing than he who believes what is wrong." -- Thomas Jefferson |
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"Martha Adams" wrote:
: :"Ian Parker" wrote in message ... : :With costs as they are I thing that only an international grouping can :explore space. However you look at it the way to reduce costs is to :rationalize. There are those whio advocate new technology - like trult :recoverable winged vehicles. There are those, like myself who are more :skeptical. : :========================================== : :Parker says, :"With costs as they are I think that only an international grouping can :explore space." : :Is this realistic thinking? : It's not. It's ideology driving possibilities rather than facts doing so. 'International space' costs so much more than doing the same thing alone that any lift we might get from international funding is more than eaten up. Other countries may benefit from international grouping, but only if there are also 'losers' in the group. : :I haven't the numbers in hand, however, I :expect that if we compare the costs of the most recent American wars vs :the cost of space, each less estimated value of their returns to :America, then one can argue that if America can afford those wars, it :can afford space ten times over. : Another fallacious argument. It makes no difference what we spend on other things. What matters is funding available vs priority given the task. Space is well down the list for the US. The only way to drive it further down the list is an 'international grouping'. : :Looking at this from another direction, under recent Republican :administration, America has slipped down badly in this world. : You're doing the same thing Ian did; letting your own ideologies drive your reasoning rather than using the facts. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
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"Jeff Findley" wrote:
: : :Furthermore, when you're talking about returning from the moon, the ability :to land at more than two locations (KSC and Edwards) is a good thing. Also, :resistance to bad weather during landing is more important, since you're :committed to a landing time when you leave lunar orbit and weather has much :more time to turn bad in that situation than after a de-orbit burn in LEO. : Why? Why couldn't you plan your return with an LEO insertion burn and just sit up there until conditions were good? -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
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