LRB's and Ares1

[frodo1008]

By the way you might find it interesting to go out to Boeings site for the SSME (even though Pratt & Whitney now own Rocketdyne I see that Boeing still has an excellent site) and then go further to the SSME incredible facts at the bottom of the page!<br /><br />Here is the link:<br />www.boeing.com/defense-space/space/propul/SSME.html <br /><br />I had the fantastic privalege of working on not only the engines for the Saturn V that placed men on the moon, but also on the truly great SSME's. Quite possibly the most advanced piece of machinery ever devised by the hand of man!!<br /><br />PS: You might also note the reliability factors for the SSMS!<br />

 

[jimfromnsf]

"Why do you think that NASA uses the venerable Delta II as its main launch vehicle for almost all of its Mars and deep space probes? "<br /><br />Because they were cheap. but not anymore<br /><br />"Delta IV from the current Heavy configuration by adding additional stages of the Common Booster Core (a relatively simple and less expensive alternate to adding more segments to a solid booster),"<br /><br />more parts, less reliable<br /><br />"the manufacturing and loading of these large rockets, this is both a very exacting and expensive procedure!"<br /><br />Not really. Easier than building a liquid engine.<br /><br />Green runs don't matter. It is not attached to the flight vehicle, just like the propellant isn't in the SRM. So your argument is invalid. <br /><br />History (the list of vehicles I provided) shows that liquid engines fail more often than SRM's<br /><br />

 

[frodo1008]

Well, obviously I am not going to convince you of anything, so I will drop out of this thread.<br /><br />Just one slight historical fact however. Wherner Von Braun would not place human beings into even orbit around the Earth using solid rocket motors, let alone taking them to the moon. And his rockets not only had a perfect flight record, they actually took us to the moon!! We will see if NASA's solid stick configuration is as good. I certainly hope so!!<br />

 

[vulture2]

Most rockets have a few failures early on. Any rocket can be made fairly reliable with enough testing. My main concern with the use of large SRBs is their relatively high processing cost. They are both hazardous and heavy from the moment they arrive. A dropped SRB segment would probably ignite, destroying the VAB. The Ares will require maintaining the entire VAB and SRB processing infrastructure, and the impressive but expensive MLPs and crawlers. In contrast the EELVs can be transported at the pad on rubber tired vehicles and/or rails at much lower cost. There are many tedious crane lifts and many hours of fairly hazardous labor in assembling the fueled segments, including such things as hand-positioning the O-rings under a segment suspended on a crane, which I believe required an OSHA waiver. So far as I know the question of reusability has not even been decided for the Ares SRB; certainly reuse is expensive for the Shuttle. For the Shuttle, the SRBs saved cost in development, but added cost to each flight. The largest SRB other than the Shuttle is on the Ariane, and it is far smaller. I simply don't see any prospect for the Ares bringing the cost of human spaceflight down to a practical level. <br /><br />Personally I feel the only cost-effective solids are the "small" SRBs used on the Delta and Atlas which use monolithic cases and nonsteerable nozzles, and can be shipped and attached in one piece; attaching various numbers or SRBs allows some flexibility in payload requirements. Even then, the all-liquid Delta IV-H, despite its teething problems, has higher performance. <br />

 

[jimfromnsf]

" I simply don't see any prospect for the Ares bringing the cost of human spaceflight down to a practical level. "<br /><br />Never was a requirement

 

[ianke]

Hi vulture2,<br /><br />You have just won the award for the most alphabet soup in one post. <br /><br /><br />"If the IUG is PLG, then the QSA can XYZ". Its simple.<img src="/images/icons/smile.gif" /> <br /><br />Ianke <div class="Discussion_UserSignature"> </div>

 

[radarredux]

>> <i>" I simply don't see any prospect for the Ares bringing the cost of human spaceflight down to a practical level. "</i><br /><br /> /> <i><font color="yellow">Never was a requirement</font>/i><br /><br />How sad. <img src="/images/icons/frown.gif" /></i>

 

[frodo1008]

It really isn’t sad, as reducing cost to LEO never has been NASA’s job, that particular job belongs to private industry. This is because NASA’s job has always been, and is now and in the future will always be pushing the envelope on human exploration.<br /><br />The main reason for this is that exploration itself will never be profitable in the financial sense. It is the job of private interests to bring down the costs of space flight (first to LEO, and then steadily, slowly but surely outward) as they must make an actual financial profit, or they can not continue in business!<br /><br />At this time I believe that Burt Rutan and Virgin Galactic are the closest to doing this over time. He seems well on his way to reducing the cost of getting to sub orbital space to such a degree that he and his partners can actually make such flights profitable. The time frame for seeing if this small first step can actually be done is somewhere around the same as the retirement of the shuttles (2010 to 2015).<br /><br />At the same time it seems that the Air Force (for its own military reasons) is doing the expensive but necessary research into flying in the hypersonic region from about Mach 4 to Mach 12 or so. I see no reason why the results of such research would be kept secret as a viable and inexpensive space industry would even be helpful for military purposes. So I would hope that Rutan’s next logical step would be (it might even be possible for him to be teaming up not only with Virgin, but even possibly someone with a lot of aircraft experience such as Boeing) to use the hypersonic region in concert with sub orbital flight to have craft navigating around the globe in only a few hours. There IS a market for such flight as businessmen consider time to be worth a whole lot of money!<br /><br />Finally, I would think that attaching a linear aerospike type of pure rocket engine (such as the ones that were built and successfully tested for the X33) to the linear rear porti

 

[jimfromnsf]

I don't not support the Stick, since it duplicates existing vehicles. Also, it is uses a non optimal first stage. But on a pure LRB vs SRB, SRB wins many categories

 

[frodo1008]

As most of my post states, I fully believe that the ultimate rocket powered vehicle for bringing down the cost of placing a pound of material into LEO is going to be a liquid powered Horizontal Take Off and Landing vehicle, based on the ideas put forth in the old NASP program. Such a vehicle would take off and land at ordinary airports using conventional jet engines, then at high supersonic speeds convert to hypersonic propulsion. Such propulsion could then be used to take such a craft anywhere on the earth in less then two hours or adding a linear propulsion aerospike type of engine (which as the craft would already be traveling at some 12 to 15 Mach would not have to be a very powerful engine) boost to LEO. Such a craft would then also land horizontally at ordinary airports, and could then be made ready to launch again in less than a day. As there is really no limit other than the sizes of the airports involved of such a craft eventually such a vehicle could take at least 50 to 100 people to LEO at a time at a cost per passenger that even upper middle income people could afford. I do realize that developing such a craft is a long term effort of some 20 years or more at least. And further that such development is going to quite probably be the province of for profit private space interests. Indeed, this is not NASA’s present job.<br /><br />The mission of NASA at present is to finish the ISS, retire the shuttle, and get the US space program out of LEO and back to the moon and beyond to at least Mars in the first half of this century at a budget level that congress can and will approve of (a budget that I would like to see much higher, but realistically I won’t).<br /><br />I am at this time worried that powerful politics might just be interfering with NASA doing this in the best manner. I hope not, but I am just not sure. And if such a true space pioneer and enthusiast as John Young is also not so sure?<br /><br />Another thing that makes me think that NASA m

 

[vulture2]

>>It really isn’t sad, as reducing cost to LEO never has been NASA’s job, that particular job belongs to private industry. This is because NASA’s job has always been, and is now and in the future will always be pushing the envelope on human exploration. <br /><br />While I agree that is true today, historically NASA was at one time very involved in reducing costs. The NACA No. 10 cowling saved so much fuel in its first year of use that it paid for NACA's entire budget from its founding in 1917. According to the book "Engineer in Charge", every NACA project, whether it was referred to as theoretical or applied, was intended to produce knowledge of practical value to aviation. NACA's mission was retained when its name was changed to NASA, though it is now almost forgotten. The Shuttle was intended specifically to reduce the cost of human spaceflight. It failed to achieve this, but does that mean we should stop trying?

 

[gunsandrockets]

<Another thing I don’t understand is why aren’t Boeing and LM pushing the EELV at this time when it seems that the SRB idea seems somewhat vulnerable with the weight problem of the Ares capsule getting worse all the time. ><br /><br />There is a rumor that Lockheed-Martin was directly warned to shut-up about manned Atlas V alternatives to the stick if it wanted any more NASA business.

 

[frodo1008]

You have a good point theoretically. However, the realities of not having a very heavy launch schedule (low numbers of flights being the result) with continuing costs (something that a pure human exploration program such as NASA's will always be plagued with) resulted in the per flight rate of the shuttle being too low to actually reduce cost by much, if at all. In fact the shuttle which was originally to have flown about once per week eventually was flown far less then every two months on the average per each year of its operational life! For anyone with any kind of mathematical accounting ability this is a formula for high cost regardless of what NASA was to do! <br /><br />The advantage of having pure for profit enterprises take over the efforts to bring the costs down to LEO is that they would first see to it that there is indeed a heavy demand for large numbers of such flights, and only then develop systems to see to it that the per flight average costs would be brought down! This is called pure marketing research by for profit enterprise, and has been shown to work in such areas as human aircraft production and flight. Which is one of the main reasons why NASA’s and NACA’s efforts for such flight have indeed been very productive in reducing the cost of air travel!<br />

 

[frodo1008]

God, I hope not! That is WAY too political for even NASA! Of course, that seems to be the way that this current administration operates as a way of life!<br /><br />But, I did like to think better of the likes of Mike Griffin, especially as it was he that was so very angry with the cost estimates of ATK!

 

[radarredux]

> <i><font color="yellow">There is a rumor that Lockheed-Martin was directly warned to shut-up about manned Atlas V alternatives to the stick if it wanted any more NASA business.</font>/i><br /><br />Just speculating here, but it may be that the upper-level management at NASA is still willing to consider using the EELVs, but they don't want Boeing and LM pushing their position to outsiders. It makes them appear to not be team players. In other words, keep the dirty laundry internal.<br /><br />I was once chewed out by a government manager/leader for talking about a major concern I saw with tech transfer. Even though the manager agreed with my position, he said I should not have said it in a semi-public forum. Nine months later I lost my funding from that group.</i>

 

[vulture2]

>>it may be that the upper-level management at NASA is still willing to consider using the EELVs,<br /><br />It looks like metal is already being cut at KSC, even though the engine for the second stage is still up in the air. There seems to be too much momentum to change course now. <br /><br />The problem is not horizontal vs vertical integration, it's mass, infrastructure, hazards, and manhours. Atlas V is integrated vertically, Delta IV is integrated horizontally, but neither requires even 10% of the labor needed for the shuttle. They are safer and much less massive, since they are transported unfueled. The Delta is carried to the pad on a rubber-tired transporter. The massive crawlers are impressive, but the railroad tracks used for the mobile service tower for the Delta and the mobile launch platforms for the Atlas are less expensive and more efficient.<br /><br />The SRBs were a compromise from the start; a quick and dirty substitute for the original flyback first stage proposed for the shuttle when it became obvious that Rockwell had somehow vastly underestimated its development cost. It was a Faustian bargain; they saved money in development but became a major part of the high operational cost that undermined the Shuttle. That they should outlive the Orbiter itself is irony of the first order.

 

[holmec]

>since it duplicates existing vehicles<<br /><br />I really don't see the purpose of reinventing the proverbial wheel (in this case the rocket). There is a lot to explore out there, so let's get off the ground and progress. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[gunsandrockets]

<God, I hope not! That is WAY too political for even NASA! Of course, that seems to be the way that this current administration operates as a way of life! But, I did like to think better of the likes of Mike Griffin, especially as it was he that was so very angry with the cost estimates of ATK!><br /><br />The problem seems to lie with NASA, not whoever is in the whitehouse for the moment.<br /><br />And the news just get's worse. See this bit from nasaspaceflight.com...<br /><br />"Hot off of the press." <br /><br />"I just got an email from a ULA employee that someone high up in NASA called people high up in Boeing and Lockheed and the word has gotten down to ULA to stop selling the Atlas as a booster that can take humans into space. Reading between the lines, if the leaves fell right, this person might come forward and testify." <br /><br />"There has got to be some rule that high level government officials shouldn't attempt to strong arm contractors from selling their product on the open market just because they compete against a government system." <br /><br />"Maybe someone in the press would like to pick this up. A juicy NASA story will always sell a few newspapers. Where is Jim Oberg when you need him?" <br /><br />"Danny Deger"<br /><br />http://forum.nasaspaceflight.com/forums/thread-view.asp?tid=8071&start=61<br /><br /><br /><br />

 

[jimfromnsf]

That is old news

 

[publiusr]

This is what I would like to plan for. Get Ares V flying, then have some Air Force money confiscated from JSF/F-22 to go to a LFB (pressure-fed) that is very strong. This would replace EELV first stages and be used as strap-ons.<br /><br />We don't need three EELV class boosters--we need one HLLV and one EELV class.