It's a step in the right direction to be sure. The ATV will be using the probe and drogue method, right?<br /><br />Edit<br /><br />Looked it up, using the RDS. <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero? Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>
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<blockquote><font class="small">In reply to:</font><hr /><p> The x-38 wasn't a failure, it was just cancelled. <p><hr /></p></p></blockquote><br /><br />It's the same thing in this case. According to http://www.suborbitalinstitute.org/news.html $300 million had been spent on the X-38 before it got canceled. It was to be a simple crew rescue vehicle. Fly to the ISS, dock, stick around for a year, and land the crew. Simple. I mean we went to the Moon almost 40 years ago for crying out loud. In the 90s though, a $300 million bought a tiny sub-scale model that could land with a parafoil. The total cost of the project was estimated at 1 billion. Okay, now tell me at 300 million already and just doing sub-scale drop tests, would it have overrun its budget once the functional and debugged item was ready to be bought?<br /><br />
<font color="yellow">"In space, the exterior design is irrelevent."</font><br /><br />Granted. However -- the mass is a critical factor.<br /><br /><font color="yellow">"...while a sphere might contain the most interior space for a given volume, it's utility might be less than using some other designs.</font><br /><br />Great. Explain some of the utility the shape of the lifting body is going to fulfill in space.<br /><br />Meanwhile -- see if you can follow this logic trail:<br /><br />- Regardless of shape -- spacecraft with a given mission have to contain a certain 'laundry list' of subsystems, expendables, living space, etc. The sum of all of these comes up to volume 'X' being required for the spacecraft to fulfill the mission.<br />- A capsule CEV of 'Volume X' will have a lower mass than a lifting body CEV -- even if you discount the subsystems that a lifting body needs, but a capsule does not.<br />- So, once in space, we have two craft with the same set of mission-requirement subsystems, expendables, etc. One has a considerably larger mass than the other. Since our goal is not to get into LEO, but to the Moon/Mars -- that mass difference is going to translate into the more massive craft requiring a lot more prepellant to have the same performance. Since this propellant needs to be <b>in orbit</b>, that equates to a lot of additional expense to perform the same mission. <br /><br />I hope the utility that the lifting body shape is going to give us once in space is <b>really</b> useful.<br /> <br /><font color="yellow">'...this is offset by the convenience of landing it precisely where you want it...</font><br /><br />Obviously you didn't bother (or have forgotten) the quote from Griffin about landing a capsule in Edwards or White Sands. Either location would be pretty convenient.
Ee, argue all you want, but The Lockheed team already debated with themselves wether a capsule or Lifting Body would be better as you can see from their concept art which features ( A CAPSULE!), So they obviously have their reasons.
<font color="yellow">"let us not forget that the Apollo capsule was conencted to a service module...<br /><br />I ask you all, which one would you rather have? the Apollo Service module is discarded "</font><br /><br />*sigh* I'll ask again -- do you keep track of what you're arguing for. The lockheed CEV... remember -- not the HL42? That would be the same CEV that <b>also has a propulsion module?!?!</b> We don't know if the LM propulsion module is discarded -- but the simplistic design would seem to imply that it is. The vast majority of the mass of the SM was the engines and propellant -- which the LMCEV needs also -- and the HL42 would need if it were designed to go to the Moon.<br /><br />Since none of us has a detailed list of what the LockMart CEV contains in the way of susbsytems and expendables -- there's no way for me to try to work up 'equivalents' for an upsized Apollo CM. All that I can do (and did) was to estimate the mass of an upsized CM with the same capabilities. Once we have (if we ever get) some more stats on the LMCEV, I should be able to provide some comparable mass estimates. What I was answering in my post was your question about:<br /><br /><font color="yellow">"Can it be scaled up by a factor of 2-3?"</font><br /><br />and your statement that:<br /><br /><font color="yellow">"A parafoil for such a big craft -remember, this is bigger than the apollo capsule, and that used 3 parachutes- will be huge, much bigger than that used in the X38 tests." </font><br /><br />The post I made showed that the craft need not scale by 2-3 times, nor would it be heavier than the X-38 (which had essentially the same capabilities... no OMS, no SM, etc.). It had an expendable DO module, but that was *above-and-beyond* the kg value used for comparision, which was landing mass.
> <i><font color="yellow">The x-38 wasn't a failure, it was just cancelled.</font>/i><br /><br />In the world outside of government, that is called a failure. <img src="/images/icons/wink.gif" /><br /><br />Nevertheless, the X-38 provides several interesting and/or instructive points:<br /><br /><font color="yellow"><b>(1) The X-38 was killed in part because of Darwinian budget competition.</b></font> ISS was running over budget, budgets were tight, and the financial meat cleaver was swinging at lots of things. In such environments even good efforts get killed, so a program manager needs to position his project and market it <i>against</i> fellow projects -- all may be good, but not everyone is going to survive. NASA will probably face this again and again in the future.<br /><br /><font color="yellow"><b>(2) The X-38 was one element in a long string of failed/cancelled projects.</b></font> The X-30, X-33, X-34, X-37, X-38, SLI, OSP -- whether NASA cannot budget well, reaches too far, or has attention deficit disorder, every NASA effort to build a post-shuttle manned space vehicle in the last quarter century has failed to reach its goal.<br /><br /><font color="yellow"><b>(3) X-38 suffers by comparison.</b></font> The X-38 was started by an organization full of rocket scientists, was under development for 7 years, spent about $300 million, and only achieved a handful of subsonic drop tests. Meanwhile, Scale Composites started with no space experience, spent about 2 years of development, spent about $25 million, and achieved three suborbital flights and received contracts to build much larger versions for commercial operations. Likewise, Bigelow's America's Space Prize is looking for a much more capable system, developed in only 4.5 years, and is only offering a $50 million prize. (interesting factoid - the X-38 test vehicle was built by Scaled Composi</i>
<font color="yellow"> *sigh* I'll ask again -- do you keep track of what you're arguing for. The lockheed CEV... remember -- not the HL42? That would be the same CEV that also has a propulsion module?!?! We don't know if the LM propulsion module is discarded -- but the simplistic design would seem to imply that it is. The vast majority of the mass of the SM was the engines and propellant -- which the LMCEV needs also -- and the HL42 would need if it were designed to go to the Moon.<br /><br />Since none of us has a detailed list of what the LockMart CEV contains in the way of susbsytems and expendables -- there's no way for me to try to work up 'equivalents' for an upsized Apollo CM. All that I can do (and did) was to estimate the mass of an upsized CM with the same capabilities. Once we have (if we ever get) some more stats on the LMCEV, I should be able to provide some comparable mass estimates. What I was answering in my post was your question about</font><br /><br /><br />I'm for lifting bodies being used! I don't care about the CEV that much, since, as I said in many posts, my bet is that it will be cancelled , probably when the US administration changes. Also, Mars missions are orders of magnitude more expensive than lunar missions and they require much more hardware in orbit.<br />Without a robust and cheap RLV , no missions to Mars are going to get off the ground.<br />Implementing a lifting body transfer vehicle is the first step towards a fully reusable launch vehicle. There simply is no better configuration to use if you want to get to orbit and back down with all of the dry mass you had when you lifted off, lob high payloads and make it all cheap! <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>
Boeing capsule vs Lockheed lifting body CEV<br /><br />I'm sort of surprised at all the heat over capsules vs lifting bodies. If anything, I would think the most controversial aspect of the Lockheed CEV is the way it combines the equivalent of the command module and the service module into a single vehicle.<br /><br />The NASA requirements for the CEV is (among other things) the ability for direct return from Lunar orbit to Earth while keeping under 20 tons launch mass. From the cutaway views of the Lockheed CEV available it looks like the fuel for direct return is there. My WAG for the Lockheed CEV is 18 tons mass including 6 tons of stored rocket propellent.<br /><br />As far as the relative merits of the Lockheed design, yes the lifting body would have a higher development risk, but I think it would pay off in lower flight risk compared a capsule. For direct return to Earth, the superior crossrange of a lifting body would be a great advantage over a capsule. Unlike a spacecraft lingering in LEO, zipping in from the moon permits only one chance at reentry. And as for the lack of volume efficiency of a lifting body, the cylindrical + boxy shape Lockheed selected doesn't look much less efficient than the cone + cylinder shape of the Apollo CSM.<br /><br />I don't know what shape the Boeing design will take, but I have another WAG. Since Grumman and Boeing are partnered, with Grumman taking the lead for spiral one, I'm basing my guess on some artwork from Grumman material. The Boeing CEV is going to be nothing much more than a 4 man Soyuz, with the same solar power arrangement, the same orbital module, re-entry module, service module configuration and the same launch shroud.<br /><br />Not that there's anything wrong with that. The Soyuz is a very efficient design, much more efficient than Apollo ever was. So the Boeing design should encompass the virtues of light weight and conservative design.<br /><br />Bottom line on CEV -- Boeing's lightweight and low cost desig
><i>For direct return to Earth, the superior crossrange of a lifting body would be a great advantage over a capsule.</i><p>True. But how much cross-range capability does the shape that L-M chose really have? The Apollo CM had a quite respectable l/d ratio, more than enough to ensure that the lunar mission landings were all within a few miles of the targeted site.</p>
"Also, Mars missions are orders of magnitude more expensive than lunar missions"<br /><br />Do you even know what "order of magnitude" means?
should I take this as a personal attack?<br /><br /><br />besides a philosophy student, are you an aerospace engineer as well?<br /><br /><br />assuming from your quote that you are British, it's pretty funny that you borrowed the name of the engineer who designed rockets that were killing your countrymen in WW2- rockets so advanced poor Brits didn't have anything at their disposal to stop them!<br /><br /><br /><br /><br /><br /><br /> <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>
"besides a philosophy student, are you an aerospace engineer as well?"<br /><br />No. But I know (as does any good aerospace engineer) that Mars missions are not orders of magnitude more expensive than lunar missions.
obviously, a space-ship designed for trip to Mars will make it to the Moon 
<br />but that is not the point. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>
<br />but that is not the point. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>"assuming from your quote that you are British, it's pretty funny that you borrowed the name of the engineer who designed rockets that were killing your countrymen in WW2- rockets so advanced poor Brits didn't have anything at their disposal to stop them!"<br /><br />I'm german and please stop adding to your original post. Just make a new one.
please give me quotes for a lunar mission and a mission to Mars, both accomplished the cheapest way possible. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>
"obviously, a space-ship designed for trip to Mars will make it to the Moon <br />but that is not the point."<br /><br />That's not the point, right. So why do you bring it up?
<br />but that is not the point."<br /><br />That's not the point, right. So why do you bring it up?"please give me quotes for a lunar mission and a mission to Mars, both accomplished the cheapest way possible."<br /><br /><br />Mike Griffin, the current NASA administrator estimates a return to the moon could be accomplished for $30-40 billion. That's the lowest NASA estimate I've seen so far.<br /><br />Griffin estimates the cost of a manned Mars mission at $100 billion although NASA did a detailed study in the early 90s that came up with a $60 billion estimate (Design Reference Mission/Mars Semi-Direct). There are still lower estimates from Robert Zubrin ($30 billion or lower, Mars Direct).<br /><br />
> <i><font color="yellow">Do you even know what "order of magnitude" means?</font>/b><br /><br />Depends on what base you are working in. <img src="/images/icons/smile.gif" /><br /><br />In most sciences, an order of magnitude usually means a factor of 10. In computer science, it frequently means a factor of 2. Sometimes I have seen it associated with a factor of 1000 (e.g., one billion is an order of magnitude larger than one million).</i>
I suspected the CEV would have wings to support a return landing. Any chance of building a fleet of vesels in our lifetimes?
if your quotes are related in any way to the CEV, please be aware that the plan is to use some of the hardware for both Moon and Mars missions. This means that the initial cost will be inflated(Lunar operations performed with overly designed spaceships), while subsequent missions will cost less (the hardware for Manned Mars Missions will have achieved a measure of maturity after being tested on the Moon)<br />The CEV is obviously a very long-lead project with a high initial investment and payoffs pretty far down the road. It will not survive another administration. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>
You still haven't said anything to justify your claim that Mars missions will be "orders of magnitude" more expensive than lunar missions. <br /><br /><br />"This means that the initial cost will be inflated(Lunar operations performed with overly designed spaceships), while subsequent missions will cost less (the hardware for Manned Mars Missions will have achieved a measure of maturity after being tested on the Moon)"<br /><br />No mission architecture has been selected yet.
Assuming all your points about the capusle design are correct , the problem is that it's a minimalist approach. It will have just enough capability to get the job done with out too much margin or additional performance. Also granted it might prove cheaper on initial development and deployment, but going down the road, we are probably going to have to come back to some sort of return vehicle that can <b>actively</b> fly to where it needs to go. The other thing is that the capsule design calls for no improvement in our technology and it's improvement that we need to really overcome the obsticles that we face. Getting the lifting body/ winged CEV to work will likley force the development of a better TPS system just as the X-33 and X-38 programs were doing before their respective cancellations. What we absolutely need to do MtM and any other exploration in space is improvements in propulsion and TPS and a real reliable means of doing the ground to LEO leg of any mission. Our whole fundation is based on this. EELV is just not a strong enough foundation to seriously build our space future on. The shuttle was, but it's high cost and reliabilty killed it. <div class="Discussion_UserSignature"> </div>
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