LM Plan Evolves Atlas to Saturn V-Class Performance

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mrmorris

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<font color="yellow">" It's use in other applications is not optimized ..."</font><br /><br />From what I've read about it (and assuming I've correctly interpreted what I've read) -- there's a bit too much hoopla about the aerospike. It's not a silver bullet. It provides a potential efficiency increase, since it allows a nozzle with an expansion that is less varying with atmospheric pressure. Ergo the nozzle will have approximately the same thrust efficiency at sea-level as in vacuum. There's an interesting article here. It lists several of the advantages and disadvantages of the aerospike (plus a full tutorial on nozzles overall). If it were going to make a *huge* difference -- it'd already be in use. Instead -- the only person that's flown one yet supposedly is that dude (forget his name -- starts with a 'G') developing the nanosat launcher.
 
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nacnud

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Yeah but thats the fuel cost for a falcon I kerosene engine. What would be the difference if it was LH fueled? It might be insignificant but I don't know the difference.
 
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mrmorris

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<font color="yellow">"What would be the difference if it was LH fueled? "</font><br /><br />Well SG has indicated in the past that it's an insignificant part of the shuttle launch expenses. <br /><br />However, there are small countries with GDPs that are insignificant compared to the shuttle launch costs... so dunno. <img src="/images/icons/smile.gif" />
 
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kane007

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"Then you have not seen a video from inside a Shuttle Orbiter during ascent. It is very rough."<br /><br />Aren't all rocket launchings rough on their passengers - whether Solid or liquid. I think I can recall some documentary footage of Apollo astronauts also getting a good shaking.<br />
 
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kane007

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I remmember an earlier post, I think from shuttle_guy, who stated that the only similarities between the current Atlas family and the ICBM's of the 1950's is the name - oh yeah and the manufacturor.
 
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drwayne

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"One Saturn 5 came VERY close to shaking itself apart."<br /><br />Apollo 13. Second stage, middle engine, turbo-pump went into POGO induced cavitation. Computer shut it down with fractions of a second of catastrophic failure.<br /><br />newsartist has had to see me go off on this enough times.<br /><br />Getting the Titan POGO down was a matter of trial and error. Some well thought out fixes not only did not work, they made matters worse.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>
 
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drwayne

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Good clarification SG. <img src="/images/icons/smile.gif" /> <br /><br />I suffer from a disease in which I basically worship the ground a lot of those guys walked on. Geniuses with slide rules. If something they tried didn't work, by golly, nature got it *wrong*! <br /><br />Note that the Shuttle has never had any problems with POGO. Part of that of course is the stack configuration, but part of it is the improved ability to simulate and deal with vehicle resonances.<br /><br />The POGO operations on the Titan were also complicated by the fact that the Air Force was being put under great pressure to man-rate the Titan. They didn't really care for that, or want it. For them, the Titan was a tool for lobbing nuclear weapons, which were pretty robust as it turns out to little things like POGO.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>
 
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gunsandrockets

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"This is a false dicotomy, since it assumes that only a 55t or 100t launcher is available. It is much more likely that both will be in existance and that either can be used as appropriate. "<br /><br />And NASA will get the money to do this from...?<br /><br />NASA already has on it's plate operating the STS, finishing the ISS, developing the CEV, probably NTR development and probably SDHLV development. All of that might be too much for NASA to handle within it's limited budget. So NASA may have to make some hard choices, some hard trade offs. That's why Northrop Grumman made the recommendation to go with a 55t intermediate launch vehicle and forego a 130t heavy launch vehicle. <br /><br />Assuming private or DOD development of a 55t vehicle within a timeframe that NASA could rely upon strikes me as wishful thinking. And no one seems to be seriously talking about developing a 100t or 130t SDHLV, because it wouldn't be able to use existing infrastructure. The likeliest SDHLV is the Shuttle C with a payload of only 45 to 77 metric tons to LEO.<br /><br />http://www.astronautix.com/lvs/shuttlec.htm
 
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gunsandrockets

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"Man it will cost about 1 billion dollars to man rate a EELV."<br /><br /><br /><br />Man rating is really a chimerical issue today (mostly employed by those trying to market a product) as made clear by Michael Griffin in this testimony to Congress on May 2003...<br /> <br /><br />"What challenges may NASA face in using an Expendable Launch Vehicle (ELV) as the boost vehicle for the OSP? Does the use of an ELV for human spaceflight pose an unacceptable risk? <br /><br />In the 1950s and 1960s, the term "man rating" was coined to describe the process of converting the military Redstone, Atlas, and Titan II vehicles to the requirements of manned spaceflight. This involved a number of factors such as pogo suppression, structural stiffening, and other details not particularly germane to today's expendable vehicles. The concept of "man rating" in this sense is, I believe, no longer very relevant." <br /><br />here is the link to the testimony <br /><br />http://www.spaceref.ca/news/viewsr.html?pid=9138 <br /><br /> <br />
 
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najab

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><i>The likeliest SDHLV is the Shuttle C with a payload of only 45 to 77 metric tons to LEO. </i><p>How the heck did you come up with 45 metric tons? The Shuttle Orbiter weighs over 100 tons and it carries a payload of up to 30 tons. Swap the orbiter out for an engine pod (three SSMEs and the thrust structure can't weigh more than about about 20 tons), and a payload 'shroud' (call it another 20 tons) and we're talking a LEO capacity of at least 110 tons!</p>
 
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holmec

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Not to mention that the Saturn V was created by NASA specs for NASA maned space program while the lockeed martin like companies need to cater to a market, Airforce, ESA, Universities...etc. Not only that but a more diversified missions, even more than one payload at a time. <br /><br />On top of that engineering techniques and material used have changed. Thus the tooling is different as mentioned by najaB. <br /><br />And to put the final nail in the coffin, the one thing that made Saturn V a success is Von Braun himself and his team. Without their experience, professionalism, and maticulous attention to detail the rocket would have been a disaster.<br /><br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>
 
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holmec

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>Von Braun didn't just suddenly appear and wave a wand to create S-5 to NASA orders. <<br /><br />No, but it was a lot of hard work. And you need a good team. Von Braun's was one of the best. <br /><br />I am not saying Von Braun created it. I am just saying the success to it was due to Von Baun and his team. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>
 
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holmec

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What is interesting about this is that coroporate companies are finally in reach of the performance of the Saturn V, a specific government project. Its ineresting that it took so long to do, 38 years (there about).<br /><br />How long will it take corporate companies to get people in orbit and on a station? And, how long will it take for privately funded deep space missions? How long will it take for space to be freely accesible to the public?<br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>
 
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holmec

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Air Force, NASA (maybe), ESA, RSA??, India??, Private companies launching space stations??... just speculating.<br /><br />I'm sure they wouldn't come out with this news without having confirmed interest in the plan. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>
 
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drwayne

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"Its ineresting that it took so long to do"<br /><br />I am not sure whether I am cynical or realistic when I observe that the fact that companies have not duplicated the capabilities of the Sat 5 is not surprising. Unless there is a payoff for a specific thing, like a Saturn 5 (or better) capacity vehicle, it will never be built by a company.<br /><br />And no, a company can not invest the huge amounts of money neccessary to build such a beast on the theory of "if we build it, they will come".<br /><br />Wayne<br /><br /> <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>
 
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najab

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><i>And no, a company can not invest the huge amounts of money neccessary to build such a beast on the theory of "if we build it, they will come". </i><p>Depends on the company - Boeing or (more likely) Lock-Mart could afford to do it. SpaceX or t/Space cannot.</p>
 
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drwayne

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There is unfortunately a difference between "can afford to" and will. A company may be able to afford to invest several billion dollars in developing something, but if there is no payoff for doing so in a definable future -odds are they will not do so.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>
 
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najab

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Oh yes, most definitely. I was just pointing out that it's not beyond the realm of proability that Boeing or LM could do it. It isn't very likely though.
 
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drwayne

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You can feel free to say something like<br /><br />"Wayne, you senile old cynical fart, how can you believe ..."<br /><br />Waynebozo <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>
 
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shyningnight

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Wayne, you senile old cynical fart, how can you believe ...<br /><br />Just kidding ;-)<br /><br />For a company to take such risks in developing a "SuperHeavy" launcher, they would have to either SEE a direct payoff, or make a GAMBLE that there would be one by the time it was ready for flight...<br />For example; when Airbus started the A380 project, it had NO customers.. and an industry that was FAR from convinced that such a large aircraft would be viable. By the time development was halfway done, they had customers. Now, when we're what, a year (?) from a first flight, there are LOTS of customers.<br /><br />It would be a HUGE gamble by a rocket-maker to make a "Saturn V class" launcher betting that "if we make it, they will come"... <br />But it's also not impossible that someone might stretch the payload envelope on a gamble. (I'll beleive it when I see it though...)<br /><br />Paul F.
 
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erauskydiver

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A380 is more of an example of why NOT to build a big rocket at risk. Airbus is struggling to just to get enough customers to break even.
 
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