Lockheed Martin's CEV is winged! (Part 2)

larper · May 11, 2005

Hence my comment above. <div class="Discussion_UserSignature"> Vote Libertarian </div>

spacefire · May 11, 2005

you obviously missed my point entirely. for a reusable system , you will not have to replace the entire craft and rebuild it. maybe you would replace a nozzle after one flight, a pump later on, same way you replace parts in your car. You can buy a fender and have it shipped to you from anywhere in the country. If you were to order a new car from another state, well, you would pay a lot to have it brought over, unless you go pick it up yourself and drive it back, which is not an option with a rocket stage or a spacecraft. by nitpicking my choice of words, you only prove your lack of seriousness and your intention to win this debate through intimidation, which of course you won't. I used the term 'ferry' correctly in context, as can be seen here: http://www.m-w.com/cgi-bin/dictionary?book=Dictionary&va=ferry&x=17&y=8 <div class="Discussion_UserSignature"> http://asteroid-invasion.blogspot.comhttp://www.solvengineer.com/asteroid-invasion.html </div>

larper · May 11, 2005

No, we both got your point, he just couldn't believe what you were saying. You obviously believe that transporting the pieces to the launch site is a prohibitive cost to a capsule based system. You also obviously think that a charge rate of $100K per year per worker is unusual. Actually, it sounds kind of low to me. Now, I have an honest question. It is not meant to belittle or demean: How old are you? You sound about 14. I remember when I was young. I had a LOT of misconceptions about how stuff worked. <div class="Discussion_UserSignature"> Vote Libertarian </div>

gofer · May 11, 2005

I personally don't see the need for 100% re-usability until the flight rate is considerably increased (10 flights per week should do it as then it's just cheaper to manufacture replacement parts), as I subscribe to the economy of scale notion (=price of unit goes down as the number of produced units goes up). Although , re-using things like nav/gyro/etc... stuff is good. Still, assuming we want reusability, I don't see at all how a capsule design loses in this at all! I mean what is that mysterious reason that prevents the insides and the structure of a capsule to be reused? Tell you what: here's an approximate launch prep order for my reusable capsule: 1. attach a new TPS shield* 2. repack parachutes, parafoils and SRMs 3. top off RCS [edited: was RMS <img src="/images/icons/wink.gif" /> ]/OMS/main prop, life-support and fuel-cell (if any) consumables 4. recalibrate the avionics and the guidance system 5. replace fuses in the power bus 6. change the high G mitigation liners on the seats 7. put on a coat of fresh paint 8. attach it to a fresh (or refurbished) second stage prop module 9. attach the above stack to the launcher ________ bill me when you are done + tips I mean, is it even THAT good compared to your vehicle? *I can tell you attaching a whole pre-fabricated disposable shield onto the bottom of my capsule is going to be just so much cheaper and faster (+ much lower labor costs) than you going with a fine comb through every tile and RCC on the leading edges/nose

gofer · May 11, 2005

<blockquote>In reply to:<hr />...I mean what is that mysterious reason that prevents the insides and the structure of a capsule to be reused<hr /></blockquote> Perhaps, it's because it 'hits the ground too hard' compared to a non-capsule? Well, the crew take it well and can themselves be reused (pardon the bad morbid humor). But titanium or aluminum alloy struts and spinners can't survive it, and just have to be thown away? Of course, not.

drwayne · May 11, 2005

It is rare to have a major business in aerospace in which the multiplier is too much lower than 2. Sometimes, in a higher overhead business, it can go up to 2.2, 2.3 or more. So 100K per worker is probably somewhere in the 40 to 50K per year salary range. Thats not real high in aerospace, looks low in fact to me. Wayne <div class="Discussion_UserSignature"> "1) Give no quarter; 2) Take no prisoners; 3) Sink everything." Admiral Jackie Fisher </div>

larper · May 11, 2005

Right. I would expect a charge rate at around $180K. Spacefire's big mistake is assuming that hardware is expensive, that the act of production is the big expense. Wrong. People are expensive. It is the act of maintanence that eats up your budget. <div class="Discussion_UserSignature"> Vote Libertarian </div>

drwayne · May 11, 2005

There is an interesting analogy here to the evolution of software. In the old days, when I was a whipper-snapper - the hardware was expensive and the people were cheap. Today, that is turned around. The hardware is cheap (and infinitely more capable), and the people are expensive. Wayne <div class="Discussion_UserSignature"> "1) Give no quarter; 2) Take no prisoners; 3) Sink everything." Admiral Jackie Fisher </div>

starfhury · May 11, 2005

Spacefire: Mrmorris and others make very persuavise argruements for the capsule design. Quite frankly it's hard to debate them very effectively on the issue. At any point, they can win on the cost, or efficiency or some other points. The true telling is to plain work the math out. If the math is done correctly, it will hold the true answer. If it says the capsule is the best way to go then, by design, nature will force our hands in that direction. But the math is not the only part of the solution. This is why even though it's cheaper and more efficient to use and operate an economy car, given the option, most people would go with a luxury vehicle. The math does not lie. An economy car is cheaper and more efficient to operate than any luxury car. In this case, the capsule is effectively the economy car and the winged/lifting body design is the luxury car. What it boils down to is what your perspectives are. I also happen to know that the best latest technology usually starts in luxury cars then eventually trickle down to economy cars. Yes, the capsule can do the job, but I don't think it's the kind of technology we can invest in which will break open the final frontier. It sets the bar too low, which means we will have to do it again and that ends up being more costly in the longer. It's getting so that people are afraid to innovate because it's to expensive or too hard to do. No one wants to give the LB design a chanee. I think that's just a myopic view. <div class="Discussion_UserSignature"> </div>

spacefire · May 11, 2005

unfortunately, we won't know until a manned lifting body is flown in orbit and back to earth, or a manned lifting body launcher is developed and tested. all we know is that after 40 years of using capsules, the price one man (not an astronaut) has to pay to get to orbit is 20 million,which is still extremely high <img src="/images/icons/tongue.gif" /> Let's not think about the Shuttle as an alternative because we'll open another can of worms. I would call the capsule (or unmanned payload) placed atop an expendable rocket a mature launch system, with both the US and Russia having quite a lot of experience using it. Yet it has not populated LEO with factories and hotels or even massive government-military space stations. In conclusion, the infrastructure created on LEO is minor: a few temporary space stations, at most two at the time, with the ISS supported by the shuttle mainly and crippled now that the shuttle isn't flying. I think without a solid infrastructure in LEO (at least one space station that can act as a staging and assembly point for cislunar or interplanetary vehicles) , earthlings will forever be limited to one shot type of missions to the Moon, and, maybe, Mars. But hey, if planting flags floats your boat, go ahead, stay with capsules and disposable rockets.. This is my final contribution in this thread. <div class="Discussion_UserSignature"> http://asteroid-invasion.blogspot.comhttp://www.solvengineer.com/asteroid-invasion.html </div>

starfhury · May 12, 2005

That's exactly the problem I have with the capsule proposals. They seek to do too little. You'd think after 40 + years we'd be a lot farther along than now. Expensive as the shuttle is, its probably launched more people into space than any other spacecraft. Had the ISS been started as Reagan wanted back in the 80's we'd be a lot farther along by now. They guys advocatiing the capsules in my opinion are missing the boat all together in terms of what we want to and should be doing in space. <div class="Discussion_UserSignature"> </div>

najab · May 12, 2005

>They guys advocatiing the capsules in my opinion are missing the boat all together in terms of what we want to and should be doing in space.On the contrary. What we (at least I) am saying is that instead of spending $15 billion dollars and 10 years developing a super-fancy CEV, we should spend as little of that time and money developing the vehicle, and as much of it actually doing something and going places.

nacnud · May 12, 2005

Seconded.

mrmorris · May 12, 2005

" This is why even though it's cheaper and more efficient to use and operate an economy car, given the option, most people would go with a luxury vehicle. " Tell you what -- let's run with that analogy -- ot at least a twist on it. A lot of people are indeed going with luxury cars instead of economy ones -- in fact, what is happening more and more is that people are leasing luxury cars because they can afford to lease a much nicer car than they could afford to actually buy. This is a great thing... sort of. They pay more money than they can really afford to drive a car for a few years. Of course when the lease runs out -- they have nothing -- because all of their money was being spent as operating costs for the luxury lease. So when the one lease runs out, they lease *another* luxury car, to have for a few years... taking up all their cash... ad infinitum. Let's move on to NASA... You do understand that one of the primary reasons we have no shuttle replacement is because the shuttle takes up such a huge amount of the budget that there's no money to properly develop its successor. So in five years we're going to have no shuttle, and we're scrambling for the cash to develop its replacement in a hurry. We do *not* need to 'lease' another luxury spacecraft to replace the shuttle just because it looks so cool when you're flying around cislunar space in it. You lament the thought that capsules are a step backward and won't push the envelope -- but that's not truly the case. We will still develop new technologies and expand our knowledge of building manned spacecraft by using a capsule design. This is a given. You don't truly think that a capsule-based system is going to have the same tech in it as the shuttle, do you? It won't advance those technologies specifically associated with a lifting body, but it will advance a *lot* of the technologie

mrmorris · May 12, 2005

"Mr Morris or whatever your name is, I am sick of your insults, sir! You obviously love taking everything I say and adding a big no in front of it. That is the capacity of your debating skills." I believe that if you look back over my responses to your posts, I generally provide a rationale behind my disagreements with the points you raise. - When you continued through the early parts of this thread to insist that a lifting body was lighter than a capsule, I created a fairly lengthy explanation of why this is not the case due to geometry and the additional controls required for a lifting body. - When you compared a lifting body to the Delta and the Falcon V, I explained that one is a re-entry vehicle and the others are boosters. - When you suggested that flyback boosters couldn't be used with capsules, I explained why this was not the case. You are of the opinion that a lifting-body design is a superior choice for the CEV than a capsule one. This is perfectly fine. You're entitled to your own opinion in this. I cannot definitively state that you are incorrect. What I can do is to explain all of the reasons that I think your opinion is incorrect. What you can do is lay out all of the reasons why you think that you *are* correct. The problem lies in the fact that you continue to present incorrect data in your reasonings. Lifting bodies are heavier that capsules for the same volume of space and materials used; you continue to incorrectly claim that lifting bodies can do 'X' and capsules cannot; and so on. I don't really have any hope (or desire really) to convince you that the capsule concept is indeed superior to the lifting body for the CEV. However, when you make incorrect statements such as you have, I *will* make a post and correct those statements (assuming someone else doesn't beat me to it) for no other reason that to try to keep someone else fro

danwoodard · May 12, 2005

>Someone posted previously that subsequent to the event noted just above >they came up with a foil lining for the composite tank. According to the >post at the time that tank system worked. Here is a link to some current development work on composite LH2 tanks, which is very promising: http://www.compositesworld.com/hpc/issues/2004/March/379 The delamination failures that occurred in the X-33 project were due mainly to liquified H2 permiating between the plies; when the tank was emptied and warmed the H2 expanded, forcing apart the laminations. Problems like this are common in development of new technologies, and cancelling the program without looking for a solution was obviously not justified. In fact, it was a mistake to kill the technology demonstrator programs, the DC-X, X-33, X-34, and X-37. They could have provided the real flight experience that would have allowed us to make informe choices. As it is, we have only analysis, and (as was amply demonstrated by the Shuttle program) analysis is not equivalent to experience. Regarding the lifing body vs capsule debate, I suspect Lockheed knows astronauts will have input, and knows they are more likely to pick a vehicle that looks as though they can fly it, event hough in fact it could obviously fly automatically and doesn't even have a windshield. Whether reuse is practical depends on how much disassembly and inspection is needed between flights, and the manufacturing cost. The capsule is less likely to be reusable simply because replacements wuill cost less, while the refurbishment cost will be similar to the lifting body. I also feel reuse isn't practical in the early years, since design is continually changing and the vehicle would have to be disassembled for every modification. The crossrange issue is pretty much a wash; the capsule can achieve the same effective cro

najab · May 12, 2005

>Not a vaild point. The Space Shuttle Orbiter is too unstable to be flown manually during entry.That's actually the point he was making - capsules can enter ballistically, winged vehicles and most lifting body shapes cannot.

danwoodard · May 12, 2005

>I believe the problem was the piles opening up and allowing air to enter the tank skin and liquify. Then it changed back to a gas when the tank was drained. I do not believe there was a hydrogen leak! that would be very bad. The original article on the metal foil sealing process in Aviation Week described air permiation (in the Alliant Techsystems tank). However the page in Composites Week included this statement (on a new tank made by Northrup Grumman): "This [metal foil] ensures that no leaking hydrogen can accumulate within the core cells, causing high pressures that can disbond the tank skins. Such a phenomenon was believed responsible, in part, for the earlier test failure of a composite cryogenic tank designed by Lockheed Martin and fabricated by Alliant Techsystems (Clearfield Utah, U.S.A.) for the X-33 prototype space plane" I do not know which process was more important in the delamination. Also, the new tank represents a different approach since a layer of honeycomb is applied to the inside of the tank and the air extracted from the cells, to serve as vacuum insulation. Since the V-2, people have tried to glue insulation to the outside of rockets, and the insulation has been falling off. Putting the insulation inside the tank is revolutionary. The lesson is clear. Immediate but crude solutions like the metal LH2 tank for the X-33 will lead to poor performance. Elegant but sophisticated solutions that could give us a practical reusable launch vehicle will take time and testing of a range of alternatives to develop. Without the now-cancelled program of unmanned, flying, and reusable technology demonstrators, we will likely end up with either a conservative and safe design with very limited capability (i.e. the CEV) or a state-of-the-art design that has unforseen costs and risks (i.e. the Shuttle).

scottb50 · May 12, 2005

I was under the impression the biggest problem was moisture getting into the laminations and freezing once the tank was loaded with very cold Hydrogen. Once it froze it expanded and damaged the composites. <div class="Discussion_UserSignature"> </div>

gofer · May 12, 2005

<blockquote>In reply to:<hr />...Putting the insulation inside the tank is revolutionary. <hr /></blockquote> This part is not revolutionary. For example the third-stage of the Saturn V had tiled LH2 insulation on the inside. There is also the school of thought that hydrogen in the *first*stage of a launcher (as in the SSTO designs so far) is madness altogether, low density and all. <blockquote>In reply to:<hr /> ...a conservative and safe design with very limited capability (i.e. the CEV) <hr /></blockquote> Limited doesn't equal bad, though. In fact it's good that it's limited. That's what architecture is all about. "A specific module for a specific purpose" should be the motto if we want to get anywhere with it. Pushing envelopes once you are in space is good though. And I hope NASA knows there are plenty of envelopes to push besides redoing already known reentry methods. I mean what else can we want from a launch/reentry module besides getting folks up and down safely and cheaply*? Aerobatics? Interplanetary navigation? [edit]* I should clarify, relatively cheaply of course as we know how with the known *propulsion* methods. If someone discovers an anti-grav *propulsion* method for 10 bucks per pound lofted, ditch everything you are doing and go that way, of course!

gofer · May 13, 2005

Only tangentially related, I think we/NASA need a small capsule/cargo/tug sort of an improved Progress-M/Souyz type system. As far as logistics go what I've learnt is that the ability to sustain the 'light but frequent' runs should run above the 'huge but rare' capability. (fresh fruit, tool replacement, medication, spring water, astronauts' kids' crayon drawings for their birthday--important for psychological health, etc...) Granularity, scalability and efficiency, if we want sustainable infrustructure. NASA should check with UPS as to how they arrived at he optimal size of their truck. [edit] and put a refueling depot up there, for crying out loud! (I'll even cut some slack for the 'heavy-lift vehicles' they might be useful there)

SpaceKiwi · May 13, 2005

Okay, have we generally agreed that the LockMart CEV proposal isn't a goer? That seems to be the prevailing opinion from my reading. For a thread concerning a lifting body design, there seems to have been a heck of a lot of capsule talk. <div class="Discussion_UserSignature"> Who is this superhero? Henry, the mild-mannered janitor ... could be!-------------------------------------------------------------------------------------------Bring Back The Black! </div>

SpaceKiwi · May 13, 2005

Actually, as so much has been said, let's take a poll on this ... <div class="Discussion_UserSignature"> Who is this superhero? Henry, the mild-mannered janitor ... could be!-------------------------------------------------------------------------------------------Bring Back The Black! </div>

rybanis · May 13, 2005

I'm Ryban, and I endorse this poll. <div class="Discussion_UserSignature"> </div>

danwoodard · May 13, 2005

to change the orbital plane 1 degree take about 500 ft/sec of Delta V I believe the crossrange maneuver is usually done not with a plane change, but rather by adjusting the apogee or perigee a few orbits before landing. This changes the orbit period, which causes the ground track for subsequent orbits to move left or right as the earth rotates a greater or lesser amount during each orbit. The change is cumulative, so if the burn is made several orbits before entry, not much delta-V is needed to bring the ground track over the landing site. Of course this only works if the latitude of the landing site is no greater than the inclination of the orbit.

Lockheed Martin's CEV is winged! (Part 2)

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