NASA to build Saturn VI (in-line SDLV)

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mrmorris

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<font color="yellow">"Why would three SRB's not get your 120 -140MT payload vehicle high enough for a second stage to get you to orbit? "</font><br /><br />With the 120 <b>US</b>ton SDHLV design, the ET/SSME is active during the first stage, but also acts as the second stage. There is then a <font color="blue">third</font>stage with the J2S thrusters. What your post suggested (i.e. simply replacing the ET/SSME with another SRB) will not make up for the loss of the total thrust they supply to the launch. The specs on the thrust and burn times for the SRBs and SSME/ET system is:<br /><br />SRB (1)<br />Thrust (vac): 1,174,713 kgf. <br />Burn time: 124 sec.<br />Total thrust supplied: 145,664,412 kgf-sec<br /><br />3 SSME/ET<br />Thrust (vac): 696,905 kgf. <br />Burn time: 480 sec<br />Total thrust supplied: 334,514,400 kgf-sec<br /><br />So you're down 188,849,988 kgf-seconds of thrust. Since the 120 <b>US</b> ton figure is for LEO, and with that much force missing, the craft won't <b>make</b> LEO, you have a sounding rocket -- even after the J2S stage performs its burn.
 
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no_way

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<blockquote><font class="small">In reply to:</font><hr /><p> "You fly the last shuttle safely if the work force on the last shuttle feels there is a path to the future for them." <br />"All in all the best path for NASA appears to be the shuttle-derived approach," Griffin said<p><hr /></p></p></blockquote><br /><br />Ok, this is nice. Because you have a workforce and infrastructure that costs you several billion dollars a year anyway that you cannot get rid of or put to do some more useful work instead of trying to compete in launch industry, the best path is to continue on down that road ??<br /><br />Theres no politically viable way of escaping shuttle, ever, is there ? <br />( Apart from another accident or perhaps "accident" ) <br />
 
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mrmorris

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<font color="yellow">"Theres no politically viable way of escaping shuttle, ever, is there ? "</font><br /><br />Well... no, actually. However, SDHLV can be viewed as a half-step along that route. It will allow a considerable reduction in the orbiter-specific portion of the workforce. This will make any future step to a completely STS-independent system (whenever that becomes necessary) much less of a drastic step for the agency.
 
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no_way

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Well, why the hell does it have to be a launch vehicle ? I couldnt care less if it were Shuttle-derived moon rover or shuttle-derived deep space observatory or shuttle-derived toilet seat or whatever suits their fancy, but its a _launch vehicle_ and NASA should have no bussiness in mucking around on launch market.<br /><br />Hey, a shuttle-derived orbital fuelling depot and shuttle-derived orbital tug would be great, as long as its launched by commercial vendors.<br />
 
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spacester

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gunsandrockets,<br /><br />It appears you've replied to everyone but me, and I know I've become that crazy guy with the Mars Settlement and ACCESS thingie, and I know I write long posts, so I'll summarize what I'm saying for your's and other's benefit. I seem to be the only one considering the potential impact of private space flight, it is a wonder to me that should be the case at this point in time. I'm used to it, but I figured by now others would at least start thinking about it.<br /><br />Mr. Griffin has a chicken-or-the-egg dilemma: Which comes first?<br /><br />The chicken: Lunar and Martian bases<br /><br />The eggs: A HLLV (Heavy Lift Launch Vehicle of whatever design) and a CEV<br /><br />NASA has been trying and failing for years to produce an egg. It is true that we want chickens that can win blue ribbons at the state fair, and it is true that you need blue ribbon eggs to make a blue ribbon chickens.<br /><br />NASA's previous eggs were either unfertilized or still-born. The henhouse is built and stands empty, NASA needs to get some chickens. They need a rooster and a chicken actually. (HLLV & CEV)<br /><br />Mr. Griffin needs to find two eggs right now that are as guaranteed to hatch as possible. The time to make blue ribbon chickens has passed.<br /><br />These eggs are less than ideal, but they work for me.<br /><br />If we can just get some chickens in the coop, non-government birds can begin to grow the flock.<br /><br />BTW, Nuclear propulsion to LEO is a rotten egg.<br /> <div class="Discussion_UserSignature"> </div>
 
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radarredux

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> <i><font color="yellow">how much mass would be required for a proper moon base.</font>/i><br /><br />I think Griffin thinks very much along these lines. I am certain that when the report comes out in the next few weeks, estimated mass to the moon will be a major part of the plan.<br /><br /><br /> /> <i><font color="yellow">Has anyone made an estimate of how much mass needs to be landed on Mars to sustain and return a crew, with or without ISRU?</font>/i><br /><br />The Mars Society in general and Robert Zubrin in particular have thought a lot about this. Zubrin's "The Case For Mars" is an interesting read. By the way, I am surprised we have not heard more from Zubrin. What is up with him lately?<br /><br />...Zzzt. Little searching found:<br />"Getting Space Exploration Right" by Robert Zubrin, a 48 page report.<br />http://www.marssociety.org/docs/TNA08-Zubrin.pdf<br /><br />Tonight's reading material has been found! <img src="/images/icons/smile.gif" /></i></i>
 
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radarredux

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> <i><font color="yellow">I seem to be the only one considering the potential impact of private space flight</font>/i><br /><br />Not true <img src="/images/icons/smile.gif" /><br /><br /> /> <i><font color="yellow">If we can just get some chickens in the coop, non-government birds can begin to grow the flock.</font>/i><br /><br />That was certainly one of the stranger analogies I have read.</i></i>
 
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mrmorris

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<font color="orange">"If we can just get some chickens in the coop, non-government birds can begin to grow the flock. "</font><br /><br /><font color="yellow">"That was certainly one of the stranger analogies I have read. "</font><br /><br />I'm not sure. But I think that was a really roundabout way of saying that private rocket firms are eventually going to f**k NASA. <img src="/images/icons/smile.gif" />
 
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spacester

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I can do mangled metaphors as well as goofy analogies. Is there a preference? <br /><br /><img src="/images/icons/laugh.gif" /> <div class="Discussion_UserSignature"> </div>
 
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space_dreamer

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I don’t have the time I used to, so I tend just to read the threads and rarely post, but I’ve just got to post on this one!<br /><br />If the figures that the SafeSimpleSoon web site are to be believed this is an amazing opportunity for NASA and I don’t see why anybody would think this is a bad deal.<br /><br /> In exchange for loosing the pretty winged orbiters <br /><br />NASA gets –<br /><br />A relatively cheaper way of getting people to orbit on the CEV (and more often and the shuttle program ever allowed) <br /><br />A super heavy lift booster.<br /><br />Just over 2 $ billon per year for new Luna landers, Habs and mars R&D.<br /><br />And to top it all NASA could get the air launched CXV from TSpace as well.<br /><br />I’ve been dreaming of a scenario like this for years!<br /><br />
 
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gunsandrockets

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"In exchange for loosing the pretty winged orbiters <br /><br />NASA gets – <br /><br />A relatively cheaper way of getting people to orbit on the CEV (and more often and the shuttle program ever allowed) <br /><br />A super heavy lift booster. <br /><br /> Just over 2 $ billon per year for new Luna landers, Habs and mars R&D."<br /><br />Yeah, and the original shuttle program promised 20 million dollar flights and ended up costing a billion dollars per flight. I'm not saying the new proposal would equal that level of a boondoggle, but I doubt the new cost savings now claimed will pan out. The most likely scenario is a program that costs just as much as the current shuttle program, but flying different, and yes improved, launch vehicles.<br /><br />That leaves money problems for NASA. With the Shuttle derived CEV booster and HLV sucking up all that money, how will NASA pay for VSE? <br /><br />
 
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gunsandrockets

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"It appears you've replied to everyone but me, "<br /><br />Well then, here you go.<br /><br />Your chicken and egg analogy is garbled as even you at one point describe both chickens and eggs as launch vehicles. Be that as it may here is the real problem: NASA doesn't have enough money for everything it might like to have and may barely have enough money to buy everything it will need. And an HLV, shuttle derived or otherwise, is something nice to have not something NASA needs to have.<br /><br />My fear is the Shuttle derived vehicle program will cost just as much year to year as the current shuttle program. Even if the new SDHLV and SD CEV launchers turn out to be fantastic vehicles, how would NASA afford anything else besides?<br /><br />One of those anything elses is nuclear power. NASA needs nuclear power to get to Mars or to stay on the moon. Not only does NASA need nuclear power the cascading benefits from nuclear power applications could ease things all down the line.<br /><br />Take Nuclear Thermal Rockets for example. The payoff for NTR could solve so many problems. With NTR you wouldn't need an HLV to lift tons and tons of chemical rocket fuel up to orbit for a deep space moon (or Mars) transfer vehicle. And even if you did need a HLV, an NTR upper stage could transform a medium lift vehicle into a heavy lift vehicle.<br /><br />So you see I disagree with your statement, "BTW, Nuclear propulsion to LEO is a rotten egg." If you have no problem with pollution from the chemically toxic Proton booster, I don't see what the big deal is about an NTR booster polluting suborbital space. And if launch accidents are your concern than you can forget about any nuclear reactor power source ever being sent to the moon or Mars. So much for your dreams of colonization!<br /><br />I think keeping the shuttle program extended with shuttle derived vehicles is a trap for NASA. Three 25 tonne payload medium lift vehicles can equal one heavy lift Shuttle C payload of 77 tonnes.
 
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starfhury

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Holmec,<br /><br />I agree with you on this. People are dismissing the wings as unnecessary. Yes, they are not necessary on space only vehicles, but when returning to earth from orbit it has it's benefits. The convenience of having them in atmosphere can be traded for the absolute efficiency of not having them at all. The real reason we have to even consider wings and parachutes is that not only do current propulsion systems lack suffieient power and efficiency, but they have horrendous prop consumption rates. We don't have enough power to come up with more elegant solutions. So in atmosphere, wings have their advantages as so aptly demonstrated by commercial aviation. If you want an even partially powered return to a particular location, having wings in atmosphere saves on prop. All other options call for passive reentry or a completely powered flight to ground.<br /><br />Another thing I'd like to point out is the gross payload inefficiency of the automobile. The vast majority of cars are barely every used at max capacity on every trip or even half the trips made. The convenience factors outweight absolute efficiency and payload capacity. That's the point we should be trying to aim for with any new space vehicle that we design and commission in the future. I'm not sure how SDLV get us there. The problem being, it's launch rate will probably be very low. This means it's payload capacity becomes very very precious and as is common with precious things, they cost a lot. What we want is throw away capacity so that things can become cheap. If we follow the scenerios of the past 60 years I do not see how we will get to that point.<br /><br />I'll say this through that Rutan has pointed us in the right direction. The reason for this is that White Knight can be launched when ever and has throw away capacity. It's now being used for X-37 drop tests or what ever else might come along in the future. Would anyone here object to me calling SpaceShipOne a space v <div class="Discussion_UserSignature"> </div>
 
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spacester

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I should know better than to try to write something clever first thing in the morning. The chicken and egg analogy is in fact garbled. Scrambled, really. It's not the kind of hard boiled analysis we need. Enough already, the yolks on me. Sorry . . .<br /><br />As always, there's too much to talk about at once. Stick to the topic then, I will.<br /><br />I don't understand why people don't see why we need 100 MT class payloads. I can understand the economic argument, draining resources from other activities. Myself, I don't think that way, but I can understand the thinking.<br /><br />Four 25 MT payloads do not equal one 100 MT payload if you waste all kinds of mass, manpower and money hooking them all together to get the 100 MT payload you needed in the first place. How do you split a nuclear power system up and put it together again?<br /><br />The increased diameter of the payload shroud alone should be enough to get people excited. Think airlocks: the bigger the shroud, the bigger the airlock you can send up to attach to your inflatable habitat, thus the bigger you can make your habitat, thus the more people you can support, thus the more you can get away from just flags and footprints.<br /><br />If the SDHLV and CEV system cost as much as STS does today, so what? We can spend the same money and actually get stuff done, what's wrong with that?<br /><br />If you start sketching out what we need at Luna and Ares to even get started at being space-faring, you soon reach the conclusion that the SDHLV will have plenty of payloads.<br /><br />If you say "well, doing that stuff is decades away, so we don't need it" then you are making a self-fulfilling prophesy. I would much rather appear the fool at trying to speed things up than making the oh so safe prediction that we will need several more decades and so we should just wait for a magic silver techno bullet that will make all these problems go away.<br /><br />If your vision for space development can't forecast more than one SDHLV <div class="Discussion_UserSignature"> </div>
 
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tap_sa

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<font color="yellow">"Would anyone here object to me calling SpaceShipOne a space vehicle like the shuttle? No?"</font><br /><br />Can SS1 achieve stable orbit, stay there for a week and do reentry like the shuttle? No? Well then, I object.
 
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space_dreamer

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spacester<br /><br />But my question is, if we don't want large payloads, then, um, what's the point? That's the part that I just don't get. If you want to move forward in space, how do you do it without increased capability? <br /><br />NASA will never give us CATS anyway, so that's no answer.<br /><br />Your right there! Leave CATS to the private sector<br /><br />gunsandrockets<br /><br />Yeah, and the original shuttle program promised 20 million dollar flights and ended up costing a billion dollars per flight. I'm not saying the new proposal would equal that level of a boondoggle, but I doubt the new cost savings now claimed will pan out. The most likely scenario is a program that costs just as much as the current shuttle program, but flying different, and yes improved, launch vehicles.<br /><br />Most of the systems of this plan are already in use; to it should be a lot easy to cost the plan more accurately.<br /><br />At what point would NASA need a flight rate of more than a single Shuttle C per year? And for how many years before that break point would NASA need even less than one Shuttle C flight per year? Yet every year NASA would have to pay to keep the new HLV program going whether it flew any missions or not. <br /><br />If there’s only one launch of mission hardware per year then there would probably be at least one launch of a fuel tanker as well. <br /><br />ESA would probably be interested in being a customer for the SDHLV, not every year, but they are getting series about mars probes and sample return, <br /><br />The Japanese space agency I’m shore would be interested in big space probes and collaborating with the US in nuclear propulsion (there space pride has been hurt by Chinas manned program) <br /><br />By 2015 the privet sector space companies should be in a position to be building really big Bigelow type space hotel / labs. So they would be customers for the SDHLV as well. <br /><br />The SDHLV is not just a Super heavy lift rocket for NASA to go back to the moon
 
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no_way

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<blockquote><font class="small">In reply to:</font><hr /><p>NASA will never give us CATS anyway, so that's no answer. <br />Your right there! Leave CATS to the private sector <p><hr /></p></p></blockquote><br /><br />The problem is, NASA gets on the way. They should have no business in launch market but they still are planning to build _TWO_ of their own new launch vehicles.
 
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space_dreamer

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I think NASA still needs its own way of getting it’s people to orbit. As for the SDHLV; the private sector can't afford to build an 80MT + rocket at the moment. (NASA meant to be the trail blazer) I don’t think They are proposing to launch commercial satellites or Tourists with these systems. <br /><br />By 2020, 100MT payloads will be well established so the private sector (Like SpaceX BFG) can come in and bring cost down further. <br /><br />Tspace and Spacedev will give us CATS <br />
 
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gunsandrockets

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"If there’s only one launch of mission hardware per year then there would probably be at least one launch of a fuel tanker as well."<br /><br />The first manned flight to the moon isn't going to happen before 2015 and quite possibly later. That would be the first time HLV would be needed, one or possibly two HLV flights per each manned moon mission. So assuming two HLV flights per mission the average flight rate for HLV wouldn't equal more than once per year until we are sending missions to the moon at a rate faster than once every two years. I don't expect moon missions at that high a rate to happen before 2020.<br /><br />"ESA would probably be interested in being a customer for the SDHLV, not every year, but they are getting series about mars probes and sample return,"<br /><br />I seriously doubt the HLV payload of 77 tonnes is neccessary for an unmanned Mars mission with a sample return. Especially now that solar-electric rockets are available for unmanned missions.<br /><br />"The Japanese space agency I’m shore would be interested in big space probes and collaborating with the US in nuclear propulsion"<br /><br />That's great but NASA can't count on running it's budget based on Japanese charity.<br /><br />"By 2015 the privet sector space companies should be in a position to be building really big Bigelow type space hotel / labs. So they would be customers for the SDHLV as well. "<br /><br />That's extremely optimistic. Even if everything goes right the first and singular Bigelow Nautilus module of only 25 tonnes will fly in 2010. Multiple Nautilus modules will more than suffice for extra capacity for some time by combining with any modules already in orbit. Plus it's much less risky to the private investor to launch three 25 tonne modules one at a time than one super-dooper-uber module of 77 tonnes lifted by an HLV booster. And the alt-space industry is likely to have 25 tonne payload class rockets by 2015 that would undercut the tonnage to orbit cost of a NASA SD
 
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najab

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><i>I seriously doubt the HLV payload of 77 tonnes is neccessary for an unmanned Mars mission with a sample return. Especially now that solar-electric rockets are available for unmanned missions. </i><p>This is the kind of thinking that will keep us on the ground forever. Sure you don't <b>need</b> 77 tonnes to do sample return, but if you <b>have</b> 77 tonnes, just think of the sample return mission you could do - your EELV launched MSR will bring back, what, 500g of what ever random rock the probe happens to land next to? My SDHLV mission will bring back 2 <b>TONNES</b> of samples, collected from a 20km wide swath by the <b>fleet</b> of rovers I sent along.<br /><br />(Yes, exaggeration, but you get the idea.)</p>
 
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radarredux

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> <i><font color="yellow">I don't understand why people don't see why we need 100 MT class payloads.</font>/i><br /><br />One reason is philosophical: What role should the government play vs. the private sector?<br /><br />The total number of global launches is still relatively small, and whenever government build their own, it shrinks the potential commercial market and scare off potential investors.<br /><br />For example, suppose the compant Space/Y comes up with a shuttle replacement, crunches the numbers, and figures it can recover its costs in 5 years with with 5 launches per year (e.g., estimate for finishing ISS) for $600 million per launch. But wait! This is 50% more expensive than the estimated $400 million per shuttle launch! How can Space/Y convince NASA, Congress, and the tax payer to spend 50% more money per launch?<br /><br />The problem is the shuttle actually costs over $1 billion per launch (once development costs have been amortized in -- which commercial companies must do)! So the $600 million for the Space/Y shuttle launch is actually 40% cheaper than the government launch.<br /><br />So the problem is that the commercial launch vehicle will never be built. The true launch cost of the shuttle is hidden. Likewise, the true cost of any SDHLV will be hidden as well.</i>
 
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gunsandrockets

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"This is the kind of thinking that will keep us on the ground forever."<br /><br />Maybe so. Perhaps you can convince the Congress to double the budget of NASA!<br /><br /><br />" Sure you don't need 77 tonnes to do sample return, but if you have 77 tonnes, just think of the sample return mission you could do - your EELV launched MSR will bring back, what, 500g of what ever random rock the probe happens to land next to? My SDHLV mission will bring back 2 TONNES of samples, collected from a 20km wide swath by the fleet of rovers I sent along"<br /><br />Talk about an exaggeration! A tripling of launch vehicle capability multiplies into 4,000 times the mission payoff, wow.<br /><br />Wheras the reality is my single rover mission could launch today, and your triple rover mission couldn't fly for at least 7 years.
 
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rocketwatcher2001

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<font color="yellow">Talk about an exaggeration! A tripling of launch vehicle capability multiplies into 4,000 times the mission payoff, wow.</font><br /><br />It's not as much of an exaggeration as you might think, I'll use aircraft carriers as an example. The U.K. and the U.S. have a completely different type of aircraft carrier style. They use smaller ships, about 1/4 the size of our Nimitz class carriers, and yet USS NIMITZ is far more effective than 4 of their carriers put together. Because the U.S. carrier is bigger, it is able to launch much bigger, longer range strikes and patrols, making it far mor effective. You could have 100 smaller, U.K. type carriers, and none of them could launch a deep strike, whereas the USS Nimitz can launch those strikes, everyday. <div class="Discussion_UserSignature"> </div>
 
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