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#1
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Heard too much and need to vent.
Now I have been following NASA's odd ideas on space policy for a few years now, where if you can forgive my desire I just need to make myself heard. These days of course it is all about the Shuttle and how this is a flawed system. Well in my view this is just working out the little left over flaws from the original design. Hey it is not a bad system after all, despite the slip-ups, where until someone goes out and builds something better, then they should keep their mouth closed. I do agree though that the Shuttle should be scrapped some time into the near future, but this is not due to it going bang and taking out another crew, but more an issue with launch mass. Also I have heard many odd ideas over the years, but I can only feel that anyone with ideas that is going to degrade launch mass should be taken out back and shot. So the one key flaw with the Shuttle is that the crew support system, landing gear, wings and the whole structure to bind this together makes for one hell of a heavy craft. Not a good idea, when what is most important here is the mass of the cargo that you can get to orbit. Also lets face the fact that if NASA is going to build a brand new craft, then they are likely to spend billions with only a slim chance of getting something remotely better than the Shuttle out of it. So if you are serious on replacing the shuttle, then to do this in the shortest and least costly way, then the only option is to work with what we already have. Hence the most logical first step is to put some engines below the main fuel tank. Get rid of the shuttle and already you have the base system to launch 100 plus tons into LEO. As I very much like the idea of maximizing the amount of cargo that can be lifted, then what you choose to do with this after that is less important. This after all can be serious ISS components, building NASA's in orbit fuel station, lifting fuel alone, parts for a lunar base, new in orbit craft, or my personal favourite of loads to paying passengers who would quickly die due to lack of in orbit resources. Well if NASA could launch them, then just maybe one of these international companies could get the idea of having them go somewhere, when after all no company would build an in-orbit tourist attraction if there was no paying visitors. So if NASA wanted to do something interesting, then they could fit seating for dozens and offer a reduced rate trip. Just do one of those up and down and they would attract a whole load of attention. Ok so worst case scenario of dozens of US citizens falling to earth is not the best idea, but should I need to say that they knew what they were getting into when they purchased the ticket. Also at this point I can only wonder about NASA's desire to use kerosene based engines. As since I already know that hydrogen produces the best reaction mass, then this to me sounds like another idea that needs a slow and painful death. In fact has anyone done any number crunching for a launch to orbit example for both types of system? As not needing the thermal protection on the main tank any more would reduce the launch mass, but I still feel that it would be worse off. One other thing that constantly annoys me is how everyone is on about what should get people into orbit instead of the Shuttle, but ideas on the much wider picture are lacking. Or at least in what I have been reading. And so if the Shuttle is one day scrapped, then lets not think about the exact craft to replace it, but the whole method in that people and cargo are moved up and down. So lets break launch, in orbit transfer and getting the vitals back down into three separate areas. The most important craft that I would like to see is an in orbit space tug, of whatever size and shape you desire. Since this craft does little beyond moving items from A to B in orbit, then so is there no need for re-entry capability. Due to foreseeing the need to have this craft manned, then it should certainly include life support. I do not see that they would have the need to get outside that much, where if anything needs repair, then it could always be dragged back to the ISS or future service station. One very important use for this craft is that once it is available, where two or three of them would be ideal, then so can you remove all in orbit maneuvering capabilities from almost all launched cargo. As after launch the space tug can just go and pick it up and move it to where it needs to be. My problem area is in figuring how to get the vitals back down again, where I do mean vitals and not the junk that NASA often brings back down. As to the junk then fit the ISS with a cannon type device and blast it out of orbit to burn up on re-entry, where as an added bonus you even get to raise the ISS a little. Maybe that is a little on the extreme side, but I am sure that they do not need to carry the junk back down again. So the big question is how much vitals is there to bring back down? If there is not that much, then making use of what Russia provides would save hell of a lot of cost in doing it any other way. Still if it is more, then the best if not only solution is to fit re-entry and landing capabilities on some of what you launch. As certainly if you remove the Shuttle, then you can connect many different types of cargo containers to this setup. Now as to getting people up there, then this should be done with as small a craft as possible. So room for a small crew, support capabilities to keep them alive long enough, with extra room for bringing those vitals down. Do I need to point out that Russia already has such a craft that has been working very well for years, where they would only be happy to share. As it seems to me that it is only a matter of national pride to produce their better craft. Well if they do want a new one, then I believe that this should be flexible enough to be launched on different rockets if needed, but for now lets stick it on top of our heavy cargo lifting capability. Also is it just me or is NASA being a bit weird in their OSP requirements concerning the injured crew member? When it is not like some astronaut is going to fall off the roof and break a leg. Sure there may be a valid reason, but it is not like they have ever needed such an emergency situation before. After all in this environment they will live on anyway or already be dead. This I believe is just NASA not wishing to kill any more of their employees, without realising that no rocket launch will ever be totally safe. I am sure that you will all be wondering about what to do with this main fuel tank now blasted into orbit. Well I am sure some use can be made for it, but if NASA really wants their engines back, then just make them detachable. Granted that it would not be easy to bring the engines back down, but with such heavy lifting capability I am sure that something extra could be blasted to orbit that would allow for engine re-entry and recovery. Well there are my thoughts to cover heavy lift, in orbit maneuvering and getting things back down, where sure my plan may not be perfect, but it is not bad either. Then of course since the ISS is in a cud orbit, then maybe NASA should build other things. Fuel in orbit would be very good, which could even make use of some of those spare tanks if needed. You could even fit an engine to the ISS and have it raise its own damned orbit. Most of all I would desire to see a space station that simply orbits between the Earth and the Moon constantly. This does not even need to be crewed most of the time, when it is just for moving people and cargo about between Earth and Lunar orbit and back again. In other words to provide the life support capabilities and decent living conditions for the short trip. Pick them up, drop them off, where you have a station nearby to help out in building a lunar base. Well in any case my main point is that with greatly increasing what you can blast to orbit, then so can you include lots of extra stuff. You are now free to pick apart my theory as you please. Cardman. In all NASA's greatest crime is that they spend billions launching people and items to orbit, where this money is wasted when it all comes back down again. |
#2
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Heard too much and need to vent.
Cardman wrote:
snip Also I have heard many odd ideas over the years, but I can only feel that anyone with ideas that is going to degrade launch mass should be taken out back and shot. Hence, all future NASA vehicles should be built using carbon nanotube reinforced composites as primary structure. They are several times lighter for a given strength than anything else available, and they only cost $900 per gram. -- http://inquisitor.i.am/ | | Ian Stirling. ---------------------------+-------------------------+-------------------------- Money is a powerful aphrodisiac, but flowers work almost as well. -- Robert A Heinlein. |
#3
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Heard too much and need to vent.
On Wed, 23 Jul 2003 12:31:38 +1000, David Findlay
wrote: They are several times lighter for a given strength than anything else available, and they only cost $900 per gram. Are they viable yet? I haven't seen any real world use of them yet. These are indeed though the only way to really get the space program happening again. Start really innovating and taking risks instead of doing what we know is old and tried and tested. One of NASA's problems in recent years is with trying to make new technology happen, where as this is easier said than done, then they usually end up abandoning projects due to it. That is why I do like them taking the route of developing key components like new rocket engines instead. Where this is just improving old tried and tested technology with the latest ideas and materials. So in the end you get a much better rocket engine to use in your new launch rocket. Why are aluminium modules still being used? Surely even kevlar or similiar would be lighter. Outside my knowledge area. I presume this is a cost issue and that the rocket fuel weighs a lot more. Well if they wanted to shift more mass, then increasing the size of the SRBs seems like the easy answer. Yet of course as the shuttle is the beginning and ending of the cargo carrying limits, then there was never the need. Inflatable modules would give the station much more room. And goes pop if hit by a micro meteorite, but I agree they could have assembled larger sections if desired. This new larger ISS component is the movie theater. ;-] Cardman. |
#4
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Heard too much and need to vent.
"Cardman" wrote:
Just too bad that the shuttle itself eats a lot of launch mass by protecting the cargo area within it. This has also imposed a size restriction on everything that went up with it since, from the hubble telescope to the ISS components. I doubt that anyone can deny that getting rid of the shuttle would give them the capacity to launch things that they can only now dream of. Think of what would happen if they launched a huge space telescope on such a system. They could even launch it in sections if desired and assemble it in orbit. As I pointed out in another post recently (to s.s.tech, I'm not sure if it got moderated yet), the Shuttle Orbiters weigh more than Skylab. And as I've pointed out on several occasions over the years, the Shuttle stack is a Saturn V class booster, with nearly the exact same payload to LEO (Saturn V: 118 tonnes, Shuttle, 117 tonnes including the orbiter but excluding the SSMEs). Except, of course, the orbiter eats up 80% of the payload of the Shuttle stack. Now, take some time to consider and to truly think about the fact that each and every Shuttle launch is roughly the equivalent of a Saturn-V launch. Think about what was done with a mere dozen Saturn-V launches (including the one which launched a complete space station) and think about the fact that we've had about 5 Shuttle launches a year and over 100 total Shuttle launches since 1981. That's 8 Apollos. That's at *least* 48 moon landings and 8 Skylabs. |
#5
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Heard too much and need to vent.
David Findlay wrote:
Why are aluminium modules still being used? Surely even kevlar or similiar would be lighter. Because in very rough terms 2/3 of the mass of a station module is something other than its hull, and all the pain and suffering involved in making composite structures 14 feet in diameter and 40 feet long was not seen as worthwhile to save the 10% of gross mass that you'd get by doing so. The term 'false economy' jumps to mind. Saving a pound that costs two thousand dollars to launch at an engineering and fabrication cost of close to a million dollars (don't laugh, that has happened before) is a really poor overall tradeoff. Optimize *mission cost* for a given capability, not launched mass. Mass is cheap. It's several times more expensive than it should be given reasonable launch providers, but it's still cheaper than engineer time. NASA spacecraft programs typically cost 3-5 times what their launch cost is. Making them 2x as large but only half as expensive otherwise to develop (larger margins, etc) would go from not changing the cost much (for a project which costs 3x launch cost) to saving 20% or more (for a project which costs 5x launch cost). And the real tradeoffs with mass are usually a much better payoff than 2x as large for half the cost, it's often 2x as large for 1/10 the cost if developed right. -george william herbert |
#6
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Heard too much and need to vent.
On 22 Jul 2003 23:23:37 -0700, in a place far, far away,
(George William Herbert) made the phosphor on my monitor glow in such a way as to indicate that: The term 'false economy' jumps to mind. Saving a pound that costs two thousand dollars to launch at an engineering and fabrication cost of close to a million dollars (don't laugh, that has happened before) is a really poor overall tradeoff. Yes, this "performance uber alles" attitude that many aerospace engineers seem to have is one of the reasons space hardware is unnecessarily expensive. -- simberg.interglobal.org * 310 372-7963 (CA) 307 739-1296 (Jackson Hole) interglobal space lines * 307 733-1715 (Fax) http://www.interglobal.org "Extraordinary launch vehicles require extraordinary markets..." Swap the first . and @ and throw out the ".trash" to email me. Here's my email address for autospammers: |
#7
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Heard too much and need to vent.
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#8
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Heard too much and need to vent.
Cardman writes:
These days of course it is all about the Shuttle and how this is a flawed system. Well in my view this is just working out the little left over flaws from the original design. Hey it is not a bad system after all, despite the slip-ups, where until someone goes out and builds something better, then they should keep their mouth closed. Against the shuttle's original goals, set by NASA, of high flight rate, low cost, and high reliability, it's a complete and utter failure. These were the goals used to sell the shuttle to congress and the (then current) administration. It was all b.s. The shuttle will never attain those goals. It's a failure against those metrics. I do agree though that the Shuttle should be scrapped some time into the near future, but this is not due to it going bang and taking out another crew, but more an issue with launch mass. So cost per kg into orbit isn't important? Just the launch mass? Please explain why cost isn't important. So if you are serious on replacing the shuttle, then to do this in the shortest and least costly way, then the only option is to work with what we already have. Hence the most logical first step is to put some engines below the main fuel tank. Get rid of the shuttle and already you have the base system to launch 100 plus tons into LEO. Congratulations. You've invented a Shuttle-C variant. Shuttle-C has been studied at length by NASA. The problem is the high cost per launch and the flight rate, which is even lower than the shuttle since you can launch more in one flight with Shuttle-C. Shuttle-C is a failure on cost, since it would cost billions to develop and would do little to eliminate the high cost of luanches. Well in any case my main point is that with greatly increasing what you can blast to orbit, then so can you include lots of extra stuff. Look at the current launch market. There is an overcapacity right now. We don't need ways to luanch more mass into orbit, we need ways to launch mass into orbit cheaply. Cost per kg to orbit is the most important factor here, not the number of kg's you can launch in one shot. Jeff -- Remove "no" and "spam" from email address to reply. If it says "This is not spam!", it's surely a lie. |
#9
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Heard too much and need to vent.
Cardman writes:
On Wed, 23 Jul 2003 01:21:31 -0500, "Christopher M. Jones" wrote: As I pointed out in another post recently (to s.s.tech, I'm not sure if it got moderated yet), the Shuttle Orbiters weigh more than Skylab. And as I've pointed out on several occasions over the years, the Shuttle stack is a Saturn V class booster, with nearly the exact same payload to LEO (Saturn V: 118 tonnes, Shuttle, 117 tonnes including the orbiter but excluding the SSMEs). Yes, except that we should keep in mind that the Saturn V was not a very good concept due to the staging. As to just have the lower engines doing all the work while the other engines sit ideal was not a very good idea. Actually, it wasn't so bad. On the two stage Saturn V, your second stage J-2 engines could be optimized to run in vacuum. This means that they didn't have to be as "high strung" as the SSME's running at their significantly higher chamber pressures. Sometimes the "one size fits all" approach of the SSME isn't so good. Certainly, but I believe the cost factor comes into this, when the complete Saturn V was not exactly cheap. So I believe that the Shuttle removed launch system is considerably cheaper. Where are the facts and figures to back this up? There was no large scale reduction in the number of buildings or workers at KSC between Saturn and shuttle operations. In fact, the shuttle uses much of the same facilities that the Saturn V did. So how is it cheaper? Where are the facts to back up your assertion that the shuttle is "considerably cheaper" than Saturn V? Besides, if Saturn kept flying and we never flew the shuttle, the development cost of the shuttle could have been spent on upgrades on the Saturn boosters. There is nothing fundamentally impossible about gradually turning Saturns into reusable boosters. Starting with recoverable first stages would have been a logical first step (so you don't throw away five F-1 engines with each Saturn V launch). Anyway, you have just made the same point that I did, when if cheap standard station components are made, then you could certainly have a lot of large stations up there in a short amount of time. At what cost? How do you launch such things cheaply? And as I said the key to all this is the "space tug", which will drag all this newly launch cargo to where it should be and help slot it together. At what cost? Your "space tug" would certainly cost NASA billions to develop and it would need constant refueling to keep it going. A reusable "space tug" was dropped long ago by NASA due to cost. Besides, with the shuttle, they didn't really need a space tug. Jeff -- Remove "no" and "spam" from email address to reply. If it says "This is not spam!", it's surely a lie. |
#10
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Heard too much and need to vent.
Cardman wrote:
Yes, except that we should keep in mind that the Saturn V was not a very good concept due to the staging. As to just have the lower engines doing all the work while the other engines sit ideal was not a very good idea. Staging is your friend. Stage early, stage often, or don't stage at all. Ok, now I would really take anyone who says that the Shuttle should be kept running out back and shoot them. ;-] Keep the shuttle running. Abandoning it before a functional replacement is in place is a sure way to lose the manned spaceflight program in the US entirely. For the same reason, ISS should be kept going. Sunk costs and such are gone. As dumb as some earlier decisions were, we have to go forwards to improve things not give up because of all we have wasted. -george william herbert |
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