VSE: LAST CHANCE TO KILL NEGATIVITY?

[magick58]

Just out of morbid curiosity why do most of you hate the idea of wings for a LEO vehicle?<br /><br />And don't use the same tired reasons that I keep seeing, because the guy a couple up posts up just shot them down. <br />

 

[spacefire]

I'll answer for him: because you can get good cross-range, RTLS abort capabilities and horizontal landing with a lifting body <img src="/images/icons/smile.gif" /><br />at the same time, you won't have the extra weight and exra TPS requirements of a wing. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[magick58]

Spacefire: don't help me by loveing your lifting body <img src="/images/icons/smile.gif" /><br /><br />Shuttle_guy: "With a wing that propulsion system would have to work harder than if the vehicle had wings."<br /><br />I didn't get that?!?!?!?!

 

[spacefire]

of course you can glide back to the launch site in a lifting body....why would YOU figure otherwise?!?!?<br /><br />http://library-dspace.larc.nasa.gov/dspace/jsp/bitstream/2002/11386/1/tp3449.pdf <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[spacefire]

may I inform you that I researched the paper I have offered you to read for one of my MAE classes and did a presentation on it? <br />Why don't you read it too, and THEN post. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[magick58]

ok let me get this straight you said that a craft with wings would work better for RTLS?

 

[wdobner]

<i>A most excellent post, wdobner! </i><br /><br />Why thank you kindly Mr. HSR Fan. And thanks for pointing me toward this board, I'm sure Gilbert B Norman greatly appreciates it. <br /><br /><i>The US could not have landed men on the moon before 1970 using that approach.</i><br /><br />Not neccesarily true. The moon program could have been done in-line with the space station program such that a station begun in 1965 or 66 could have been complete enough to allow the staging of a moon mission out of it by 1968 or 69. It most likely would have been a simple chemical rocket and basically a bare propoganda attempt (like Apollo), but the existence of a space station and as such would leave us in a much better position after going to the moon to return regularly. It's a whole lot easier to ask congress for enough money for a Titan 3 loaded with fuel and the crew to go back to the moon via a craft already in orbit rather than blowing an entire Saturn V to do what the previous mission already put in space. Whether we would have made it to the moon by 1970 is somewhat iffy, as it was on the Apollo program, but certainly we would have stayed on the moon much more easily with a space program which didn't attempt to fly from the earth to the moon and back directly. <br /><br /><i> And it doesn't really matter what might have been. What matters is the present and the future.</i><br /><br />Which is why we have a thread on this board detailing comments the current NASA administrator made disparaging his predecessors?<br /><br /><i> I say it again: Griffin's plan is the best we'll get. </i><br /><br />Hardly. There are many better ways to the moon than the one Mr. Griffin has committed us to. We could very easily push for the development of an SSTO and work from there, using the lower cost per pound to LEO to get to the moon in a more sustainable manner. The current lunar program makes no great advances which create economy to allow it to be maintained, so we're still going to end u

 

[vt_hokie]

<i>"Why thank you kindly Mr. HSR Fan. And thanks for pointing me toward this board, I'm sure Gilbert B Norman greatly appreciates it."</i><br /><br />Haha...you know, I didn't even make the connection! Glad to be of assistance...welcome aboard! <img src="/images/icons/smile.gif" />

 

[john_316]

Matt Sorry I haven't been on in some time but I do disagree with one point of this arguement.<br /><br /><br />They moan because it doesn't have fancy nuclear or ion propulsion systems: <br /><br />NOT GOING TO HAPPEN... <br /><br /><br />The likely use of regular chemical rocketry to Mars in less than a 6 month travel time frame will never happen. The likelyhood of Nuclear Power to propel the Mars Craft in a rapid sufficient manner is likely to happen. For the saftey of the crew and use of consumables in route I think that will happen...<br /><br />My 2 cents.<br /><br /><img src="/images/icons/smile.gif" /><br />

 

[mattblack]

I only say 'Not Going To Happen' because of all the anti-nuke sentiment that has always gone on. And unless there is a real seachange in attitude within the next 5 years or so, time will run out. Also, there have been no statements that future lunar missions will use a small reactor. I know that chemical (LOX/LH2) wont get you to Mars in less than six months. With nuclear-thermal you might slice the transit time to 4 months and with VASIMIR, 3 months. However, if you want to make aerobraking a feature of your mission architecture, you cannot go much faster than the 6 month figure, because the aerocapture velocities start getting dicey. Also, any use of nuclear-electric, VASIMIR, and maybe even nuclear-thermal propulsion starts to take the mission architecture away from "standardised" hardware that is both derived from the coming lunar spacecraft and is well-understood from a conventional engineering standpoint.<br /><br />Now, I'm all for thinking outside the box, but if Mars mission hardware and architecture starts deviating too far from the low-cost and Zubrinite schools of thought, the costs start spiralling into the $250 billion dollar realm of 'paper spaceship' fantasies and what used to be called the 'Battlestar Galactica' mentality.<br /><br />We all know that nuclear power for a longstay Mars mission is virtually ESSENTIAL. Fullstop, can't be argued. After all, your ascent and Earth-return propellant would be manufactured from the Martian atmosphere through the Sabatier methanation process. Such a process requires months of multi-kilowatt hour electricity. A nuclear reactor it HAS to be.<br /><br />But to depart Earth orbit for Mars in a 45-tonne spacecraft requires at least 110 tonnes of LOX/LH2 burned by high isp engines. The way that mass fractions are, if you increased the departure payload to 60 tonnes, you'd need about 140 tonnes of fuel. The higher you increase your trans-Mars injection payload, the worse the ratios get and so on and so-forth. If your pay <div class="Discussion_UserSignature"> <p> </p><p>One Percent of Federal Funding For Space: America <strong><em><u>CAN</u></em></strong> Afford it!!  LEO is a <strong><em>Prison</em></strong> -- It's time for a <em><strong>JAILBREAK</strong></em>!!</p> </div>

 

[JonClarke]

You don't need nukes to run an ISPP plant on Mars. In fact, you want to follow the KISS principle you want to avoid one if at all possible. In fact, for a semi direct architecture with a four person crew you need only 20 kW to run the whole ISRU plant. Operating 10 hrs per day this could produce all the consumables needed by the mission in before the crew actually gets to Mars. This amount of power can be provided quite nicely on solar cells, on equivalent mass to a reactor but with greater simplicity, reliability, and lower risk (technical and political) Larger missions or ones to high latitudes would need reactors.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[spacefire]

<font color="yellow">So you tell ME why YOU think a lifting body can do a RTLS without a propulsion system to get it back to the launch site. BTW that is what the LS means in RTLS.. </font><br />why don't you read the paper? you can download Acrobat Reader free from the Internet.<br />In the paper you will see that over a portion of the ascent, a lifting body mounted atop a rocket would be able, upon any malfunction of the booster, to separate (using the abort motor) and glide back, performing the so called <b><font color="red">Return To Launch Site</font>/b> abort.<br /><br /><br /></b> <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[wvbraun]

<br />"Not neccesarily true."<br /><br />BS. NASA barely made it with the Apollo architecture. Starting in 1961 there is no way NASA could have reached the moon by 1970 using von Braun's original plan.<br /><br /><br />"There are many better ways to the moon than the one Mr. Griffin has committed us to."<br /><br />I didn't say there is no better plan but the VSE is the best plan with a fair chance of actually being implemented.<br /><br /><br />"We could very easily push for the development of an SSTO and work from there..."<br /><br />LOL. Ever heard of X-33? NASP?<br /><br /><br />"I would say that the Shuttle is both hardly a failure, and not a representative of what a spaceplane should be."<br /><br />I wasn't referring to the Shuttle. See above.<br /><br /><br />Regarding scramjets: We don't need them for achieving CATS. It's just another fancy technology project to keep the wind tunnels open. And no, NASA has shown no interest in seriously trying to lower the cost of spaceflight.<br /><br /><br />"I hardly see any private group near LEO"<br /><br />SpaceX

 

[centsworth_II]

<font color="yellow">"Just out of morbid curiosity why do most of you hate the idea of wings for a LEO vehicle?"</font><br /><br />Wings are great for a craft designed for frequent, repeated trips to and from LEO. The trouble (for you, not me) is that NASA is charged with going to the Moon and Mars. It would be wonderful to have a budget large enough to accomplish many big projects at once: Return to Moon, Space Plane, etc.... But NASA does not have that kind of budget and the mission is: Return to Moon, NOT Build a Space Plane. The budget simply is not large enough to include a Space Plane as part of the Moon program. <div class="Discussion_UserSignature"> </div>

 

[vt_hokie]

<i>"The budget simply is not large enough to include a Space Plane as part of the Moon program."</i><br /><br />Which is precisely why I cannot get behind this plan. I feel that the right course of action is to develop a "space plane" that will make access to LEO safer, cheaper, and more routine before we worry about sending a few token missions to the lunar surface.

 

[mlorrey]

Fixing the external tank can be done simply: the falling foam chunk problem didn't arise until the CFC ban treaty forced NASA to outlaw the use of freon in cleaning the surface of the ET. Less capable cleaners are now used and thus foam has a harder time sticking to the tank well.

 

[wdobner]

<i>BS. NASA barely made it with the Apollo architecture. Starting in 1961 there is no way NASA could have reached the moon by 1970 using von Braun's original plan. </i><br /><br />How do you know this? Looking at it from 1961 it seems equally unlikely that Apollo would make it. We can't go back and change things, but certainly to dismiss the possibility that an early space station would allow an EOR scenario with an Earth-Moon shuttle vehicle is rather irresponsible. I could just as easily say it'd be impossible the Saturn V could be built in a great enough quantity for a moon shot to occur, but I would be proven wrong by what happened. I believe the apollo program managers not only could have gotten a space station operational, but could have used that station to get astronauts to the moon by the end of 1969. <br /><br /><i>I didn't say there is no better plan but the VSE is the best plan with a fair chance of actually being implemented. </i><br /><br />That's because Mr. O'Keefe and Mr. Griffin have systematically eliminated all other options to the moon plans forced upon us by Dubya. A more rational approach would be to lower the cost of LEO access and THEN go to the moon, which would make it more likely that we'd be able to keep a long term lunar space program going. It's in NASA's best interests to develop cheap access to LEO, and it *ought* to be an imperative for our moon program and such. What will we do when we get to the moon? How are you going to keep congress from cancelling it this time? Now we've even knocked off programs which could have furthered the cause for manned spaceflight by dropping space telescope and nuclear space propulsion programs. A few nice pictures of a planet going around a distant star could make a very eloquent case for manned spaceflight, and it'd be much easier to get to Mars and beyond with nuclear propulsion, but instead we're betting it all on a moon program which offers few improvements to our long term inhabitation of s

 

[mlorrey]

<blockquote><font class="small">In reply to:</font><hr /><p><br />"Just out of morbid curiosity why do most of you hate the idea of wings for a LEO vehicle?" <br /><br />Wings are great for a craft designed for frequent, repeated trips to and from LEO. The trouble (for you, not me) is that NASA is charged with going to the Moon and Mars. It would be wonderful to have a budget large enough to accomplish many big projects at once: Return to Moon, Space Plane, etc.... But NASA does not have that kind of budget and the mission is: Return to Moon, NOT Build a Space Plane. The budget simply is not large enough to include a Space Plane as part of the Moon program. <br /><p><hr /></p></p></blockquote><br /><br />NASA already has the RBCC propulsion system for its GTX SSTO demonstrator developed and wind-tunnel tested. Of course, their choice of fuels sucks for an aerodynamic vehicle, but you can't expect NASA to do everything right.<br /><br />On the plus side, NASA will likely cancel this program too, allowing private industry to buy the technology surplus and make it really happen in a profitable way.

 

[wdobner]

<i>On the plus side, NASA will likely cancel this program too, allowing private industry to buy the technology surplus and make it really happen in a profitable way. </i><br /><br />Oh yeah, real great. Now SpaceX, Arianespace, or even SeaLaunch can pick up our last best hope for truely convenient access to LEO and sit on it GM-style so they don't have to change their business model or actually innovate.

 

[spacefire]

yup. then we can send a lot more stuff to the Moon with the same budget! <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[wvbraun]

"Looking at it from 1961 it seems equally unlikely that Apollo would make it...I believe the apollo program managers not only could have gotten a space station operational, but could have used that station to get astronauts to the moon by the end of 1969."<br /><br />This is getting ridiculous. The Apollo managers and engineers at the time concluded that reaching the moon "before this decade is out" was only possible using the very simple Apollo architecture and even then just barely. That's the reason von Braun dropped his earlier plans - but maybe you want to pretend that you know better than NASA's finest...<br /><br /><br />"A more rational approach would be to lower the cost of LEO access and THEN go to the moon"<br /><br />Not going to happen. As you already pointed out in your post NASA's RLV programs failed for various reasons and I'm absolutely certain that they wouldn't do any better if they were given yet another chance. <br /><br /><br />"Neither of which ever got the chance to fly, so how can they be judged a failure? A bureaucratic failure, a failure of NASA's budget, yes, but a conceptual or engineering failure? Hardly."<br /><br />These programs failed in every way imaginable. They were both management/bureaucratic failures and engineering failures. We don't have the technology for SSTO spaceplanes and we won't have it any time soon. Scramjets don't help that much, something the NASP people realized too late. It would never have worked no matter how much money NASA had spent/wasted on this ill-concieved project.<br /><br /><br />"I do believe a great many aerospace scientists and engineers would tend to disagree with you."<br /><br />And a great many would tend to agree with me.<br /><br /><br />"Space X appears offer nothing new outside of a remarkably low cost."<br /><br />That's a bizarre statement. What more do we need? If we don't need scramjets to achieve CATS then why develop them? Because spaceplanes are so 'sexy'?

 

[vt_hokie]

<i>"...and sit on it GM-style so they don't have to change their business model or actually innovate."</i><br /><br />That's so true regarding GM! I'm looking to replace my 1997 Saturn SL2 which currently has 220,000 miles on it, and I'm not interested in very many GM products. It's truly a shame that GM turned Saturn into just another division, eliminating the independent management and engineering team as well as the unique labor agreement. Now, they're even phasing out Saturn's trademark dent resistant plastic body panels.

 

[scottb50]

I have a 94. Second engine, second transmission, the security system melted the wiring and failed. Parts and service are as much or more than Cadillacs.<br /><br />Good idea, poor execution in my opinion. <div class="Discussion_UserSignature"> </div>

 

[vt_hokie]

That sucks. I guess I got lucky with mine!

 

[vt_hokie]

<i>"That's because Mr. O'Keefe and Mr. Griffin have systematically eliminated all other options to the moon plans forced upon us by Dubya. A more rational approach would be to lower the cost of LEO access and THEN go to the moon, which would make it more likely that we'd be able to keep a long term lunar space program going. It's in NASA's best interests to develop cheap access to LEO, and it *ought* to be an imperative for our moon program and such."</i><br /><br />Absolutely. I agree 100%. <br /><br /><i>"Worldwide there are many programs working to develop working scramjets, we just happen to currently be the most advanced nation when it comes to them."</i><br /><br />If this thing really does exist, I hope that it emerges from the black world soon. I'd love to know what type of propulsion system it has!