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#11
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Heard too much and need to vent.
Cardman wrote:
(George William Herbert) wrote: Optimize *mission cost* for a given capability, not launched mass. Mass is cheap. Well how would you have liked to have been able to fully complete the ISS in just five launches instead of dozens? One launch, or two. Anyway, what we are doing here is optimizing launch costs, where to say this is not important due to the mission costs is just making excuses. I am going to say this again, slowly: If the mission costs 5x what the 'baseline' launch cost does, and you spend all your effort trying to reduce the 20% fraction dedicated to launch, you are an engineering economics fool. Please keep in mind as I say that, that I have been trying to get a BDB low cost launch company going for a number of years now. I know exactly how bad the launch cost situation is compared to where it might or should be. And I am all for decreasing engineering time... Or more correctly to refocus and optimize engineering time. Then focus on the expensive parts, if you're doing a program. There is a credible argument to be made that if launch costs drop first, then project costs will follow. But... for optimizing NASA type programs, generally 'throwing more mass at it' is a cost optimization. NASA spacecraft programs typically cost 3-5 times what their launch cost is. And what if the ISS had been made from "standard units", where NASA is so into making everything unique. Just plug the ISS together like a lego model and if you get bored you can always switch it around. Sure you need the extras like the solar panels and canada arm, but again these extras should be made as standard units. In this way technology gets improved slowly between different units, where someone has a bright idea and standard unit 3A is produced. Had this all been done, then sure the initial cost would have been high, but you would have completed the ISS by now. In fact there would be many ISSs up there including a real big one (the Hotel!). How much aerospace systems engineering experience do you have? What exactly do you propose to put in each 'standard unit'? Systems wise, I mean. Station control? Water loop life support stuff? Electrical power storage and distribution? Air recycling? Equipment racks? Human bunk space, galley and head space? What? What sized standard modules? With what docking or berthing facility between them? What's all this do to your mass budget, when berthing hatches and extra wiring and piping and all are all included? The probes and even craft can just be made the same way, when sure you got to worry about different environments between different planets, but at the core they can be the same. I repeat: how much aerospace systems engineering experience do you have? -george william herbert |
#13
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Heard too much and need to vent.
On 23 Jul 2003 13:36:37 -0400, jeff findley
wrote: Cardman writes: And what if the ISS had been made from "standard units", where NASA is so into making everything unique. Just plug the ISS together like a lego model and if you get bored you can always switch it around. I'm glad to see that you think that space stations are as easy to build as Lego models. You're ignoring the analysis of the system as a whole It should be made to survive the more harsh environment of space, with certainly a small living section to handle solar flares. Apart from that these things are primary for living in, storage, docking, construction and repair. and you're ignoring the cost of the individual modules. These things aren't cheap. What I am not ignoring is that NASA likes to make everything unique, where as a result most of the expense is in the design and testing. For example NASA spent very many billions even before building any of the main components of the ISS. So ignoring these aspects just how much does the raw materials and assembly cost? With a system planning on moving into mass production, then even that could be reduced. Even Russia built themselves a very nice space station out of the top section of their rockets. There you go standard sections that were not even largely planned well for a space station thus slotting together on the cheap. How do you propose to make your "standard units" cheap? By not making them unique, thereby spreading the design and testing costs between the units. For example now that you know how to make the ISS, then how much does it cost to make a second or third one? Having those second and third ones orbiting the Moon and Mars, would prove quite interesting. Still the ISS is aimed at research, which is something that I would never do beyond a standard lab and medical facility. What would the development costs be for these units? Beats me, but if you want space stations around the different planets, then this is the cheapest way to do it. Having a space station around each planet would provide a complete support facility for all activities at that planet. As you can tell I am a dictator... :-] And we all know how cost effective dictators can be, especially when the decisions they dictate aren't based on any sort of cost analysis, but on the whim of one person. J.F.K did get us to the Moon. Sure it was not cheap, but this set the standard bar that NASA has failed to live up to ever since. So certainly it would not be cheap, even if I am certainly aiming for efficient use of funds, but if I ever had the chance, then I would promise you a moon base within 10 years and an ever growing number of my standard space stations. And even dictators have to live in the set budget of others... NASA could even offer to build a space hotel for interested companies in this situation, using standard components of course, when the chance of paying guests being delivered is increasing all the time. And so NASA in the future should certainly think about funding themselves, where tourism is the obvious first choice. Cardman. |
#14
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Heard too much and need to vent.
On Wed, 23 Jul 2003 20:29:43 +0100, in a place far, far away, Cardman
made the phosphor on my monitor glow in such a way as to indicate that: And so NASA in the future should certainly think about funding themselves, where tourism is the obvious first choice. Yes, that's what we need, another government agency competing with the private sector for private services. -- 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: |
#15
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Heard too much and need to vent.
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#16
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Heard too much and need to vent.
Cardman wrote:
(George William Herbert) wrote: How much aerospace systems engineering experience do you have? None, but I do have a good talent in seeing how things should be done. I have a short textbook recommendation list: _Spacecraft Systems Engineering_, Fortescue & Stark ($75) _Rocket and spacecraft propulsion_, Turner ($80) _Rocket Propulsion Elements_, Sutton (6th or 7th ed) ($110) _Modern Engineering for Design of Liquid-Propellant Rocket Engines_, Huzel & Huang ($110) _Reducing Space Mission Cost_, Wertz & Larson ($45) _Space Mission Analysis and Design_, Wertz & Larson ($45) _Human Spaceflight: Mission Analysis and Design_, Larson & Pranke ($45) _Aerospace Vehicle Design, Vol 2_, Woods (this is long out of print, though) _LEO on the Cheap_, London (http://www.dunnspace.com/leo_on_the_cheap.htm) Unfortunately an expensive list, but important. Where all I am hearing about improving their launch system are excuses, both valid and invalid, to stop this important thing happening. Some of what you are hearing are excuses. Some of what you are hearing are professionals who simply want you to understand that what physics, engineering, and economics actually let you *do* as opposed to talk about are a lot harder than you seem to suppose. If you want to figure out ways to do that which we currently believe to be impossible... go for it. DARPA and NASA SBIR grants and the Institute for Advanced Propulsion are out there. If you want to figure out easier ways to do things which we currently believe are very hard... understand why they are hard first, please. It cuts down on everyone's frustration 8-) [..] Do you really like making my simple good points so complex that it wastes every ones time with things that cannot be answered? These things can be answered. The question is whether the detailed answers support your origional idea or make it less attractive. Knowing what you can and can't do right now, and why, is important to working to improve the situation. The devil is in the details. Don't let the Devil get you. Get him first, *then* propose a way forwards... -george william herbert |
#17
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Heard too much and need to vent.
On 23 Jul 2003 13:30:22 -0400, jeff findley
wrote: Cardman writes: 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. So we come to aerospike engines, which is something that only now are starting to get off the ground. 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? The problem is that the Saturn V with all its stages was considerably complex, where again the Shuttle needs a huge amount of handling. I can certainly see changing the Shuttle system into a cargo lifter could well result in the closure of a couple of buildings and the loss of quite a few workers. That by the way is a good thing... Where are the facts to back up your assertion that the shuttle is "considerably cheaper" than Saturn V? Not the Shuttle, but the much technically simple and easier to handle launcher that could be made from it. 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. I agree, but congress did directly pay for the Shuttle out of extra funds, which makes that extra Saturn V upgrades questionable. 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). And I fully agree that the Saturn V could have been keep working, but the point is that they got rid of it and used the Shuttle instead. Also I think we all know by now that the Shuttle is on borrowed time, when it is just too complex for its own good. So my idea in just making use of most of the exact same Shuttle systems in a new Shuttle-less cargo launcher is again improving what there already is instead of totally scrapping it (at extreme cost) to making something new. 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? Considerable to begin with, but much less for each one produced. Since this project could well make use of a lot of what was done with the ISS, then I would say that the first station could be made for about half the cost. Yikes, I hear you say. Then making copies could be quite cheap, where these is minimal research and testing to be done. How do you launch such things cheaply? That is the easy part. See my ideas on a Shuttle-less cargo launcher, which could build the likes of the ISS in just one year. 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 Certainly, but I also considered the idea that the Shuttle if kept in orbit would do a perfectly fine job. So if there was no fatal reason why the Shuttle could not be maintained in orbit, then hey we have just saved billions. As I said it is better to improve on what NASA already has instead of building from new. The space tug idea is important, when sending up dumb cargo saves the otherwise complex and very expensive control system from having to land and be reused. and it would need constant refueling to keep it going. Yes, but fuel can be launched into orbit as well you know, where the fuel used is only a bit more than with their up / down system. The cargo is launched into orbit on the right ISS heading, where the Shuttle then leaves the ISS, goes to the collection point and then sees how well it can move 100 tons of cargo. Some of that cargo would be the fuel that the Shuttle needs. A reusable "space tug" was dropped long ago by NASA due to cost. And as I said NASA's key failing is in launching this heavy Shuttle each time and have it re-enter the atmosphere, lands and then be virtually rebuilt before the next launch. Very costly and time consuming. Doing this Shuttle launch system instead of moving the cargo about in orbit is what is taking up 80% of the launch mass. Besides, with the shuttle, they didn't really need a space tug. And very soon there will be no more Shuttle, unless they launch it into orbit and keep it there. Obviously NASA will be needing a new heavy launch system after this, where my idea is certainly a good one. Start work on it now and the earlier you can solve this Shuttle danger problem. After all the problems with the Shuttle is in launching it and bringing it back, where keeping it in space makes the Shuttle safe. Cardman. |
#18
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Heard too much and need to vent.
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#19
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Heard too much and need to vent.
On Wed, 23 Jul 2003 23:14:26 +0100, in a place far, far away, Cardman
made the phosphor on my monitor glow in such a way as to indicate that: Maybe one day I will have to look into where NASA spends its budget, Maybe you should do that *before* endlessly pontificating on subjects that you don't know much about... And yet no one has yet provided any facts to prove my ideas wrong. All these very experienced people and I wonder why that is, where instead we get snide comments. Maybe because we have better things to do with our time than go through and deal with a huge load of nonsense line by line. Maybe, because I am close to the truth, where some people just don't want to hear it. laughing Yes, that's what it is. You've broken the conspiracy wide open... -- 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: |
#20
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Heard too much and need to vent.
Cardman wrote:
(George William Herbert) wrote: Cardman wrote: (George William Herbert) wrote: How much aerospace systems engineering experience do you have? None, but I do have a good talent in seeing how things should be done. I have a short textbook recommendation list: _Spacecraft Systems Engineering_, Fortescue & Stark ($75) _Rocket and spacecraft propulsion_, Turner ($80) _Rocket Propulsion Elements_, Sutton (6th or 7th ed) ($110) _Modern Engineering for Design of Liquid-Propellant Rocket Engines_, Huzel & Huang ($110) _Reducing Space Mission Cost_, Wertz & Larson ($45) _Space Mission Analysis and Design_, Wertz & Larson ($45) _Human Spaceflight: Mission Analysis and Design_, Larson & Pranke ($45) _Aerospace Vehicle Design, Vol 2_, Woods (this is long out of print, though) _LEO on the Cheap_, London (http://www.dunnspace.com/leo_on_the_cheap.htm) Unfortunately an expensive list, but important. Sounds like interesting reading, which I may one day soon look into, but as the subject says I have just heard too much about the Shuttle and replacements as of late and just want to vent my own view. You are admitting, then, that your own view is not based on any experience or familiarity with the details of how space and space launch engineering work, and that you are not currently interested in learning those details? And come on it is not such a bad view... It's not such a good one either. The reason that nobody has built a Shuttle-C to date is not engineering difficulty... even the conventional aerospace contractors could do it in a couple or three years and a couple of billion dollars at most, if they wanted to. It's that nobody has a market for it. The only thing you can really conveniently launch in 100 ton chunks is a space station. The (singular) space station is already up in orbit. Do you have someone who is going to pay to launch something else that sized? -george william herbert |
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