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And Dennis applies the smackdown... bravo
...Just don't like the idea of building anything at ISS. The orbit of ISS puts a serious dent into the payload mass that can be orbited from KSC, and building large things out of small pieces has proven to be an inefficent way of making spacecraft.
Launch major componets on a HLV (Shuttle-C/Z or EELV-derived) unmanned with self-docking capacity or a tertiary on-orbit tug. The first two modules of the ISS were joined without any preexsisting structure or direct human oversight. Launch cargoes on EELVs for the moment and worry about reuseable launchers later, unless they can be done on the cheap (DC-X). Go ahead and build a nuclear reactor, we'll need one for Mars and for the majority of the Lunar surface.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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And Dennis applies the smackdown... bravo
Will this become point, counterpoint? Wingo v Bell as a regular feature?
I daresay the spacedaily website operators hope so. . .
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Edit: Re-reading the Wingo piece I find this:
Mr. Bell continues in his strawman development by making claims about how many EELV's it will take to implement the Lunar initiative. To use his language, he is dead wrong. While it could take the number of EELV's that he speaks of, it would only be if we were completely stupid in how we built the system.
Mr. Bell implicitly assumes that everything will be thrown away after every mission requiring multiple launches each time to put up new hardware. Where is this defined in any of NASA's plans? Answer, it is not.NASA's NeXT team explicitly called for fully reusable chemical and solar electric tugs as well as the fuel modules for the refueling of both systems.
and then this:
The solar electric tugs (my company is already building a lightweight version for the commercial market) would be used to move very heavy payloads that do not require fast transit such as the L1 station and lunar landers, and the chemical tugs would carry the humans rapidly through the Van Allen radiation belts.
Hopefully NeXT will be followed. Otherwise Bell would be correct about the number of EELV launches needed, right?
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Here is why I am primarily on the fence on this whole SDV thing... yes, there is a definite use for the thing, and yes it does make "large" payload to space more managable... but that is exactly what Saturn and the Shuttle gave us.
Look where we are, now.
Now, I don't have a problem with the SDV or HLLV unto itself, it's the underlying architecture of EELV and HLLV/SDV that I consider.
When we have a big basket to fill, we won't launch until the basket is filled. That means infrequent flights, every once in a while, when we have all the material ready. This constrains our ability to really try out multiple avenues, or smaller steps.
EELV though is a smaller basket. That means more launches. That means more routine. That means consistent production and utilization. Wouldn't this follow along the lines of mass-production/consumption= decrease in cost?
Wouldn't EELV mean more launches, consistently? It would also provide an incentive to further upgrade and refine the exsisting private market launch supply to meet this new demand. This would in turn reduce cost for others who wish to utilize these rockets. Uncle Sam helps bring launch costs down through purchase, not through production.
This has the next effect, with EELV, to come within the range of private organzations and universities as they buy cheaper rockets, or small payload space on the EELV that is being used by Uncle Sam. The only people who need the HLLV are the lun-ies and the military afterall.
I believe I have read elsewhere that NASA (or some other) is looking at EELV to help with ISS construction (maybe I was daydreaming). I haven't heard from Boeing... bastards.
Bell isn't right about the number of EELV launches becuase there simply is no CEV yet to define the number of launches needed. We don't know what the entire architecture is, what kind of approach will be used, etc. But of course, with all things, Bell could still be right.
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As usual, the devil is in the details... instinct would say, that if you launched alot of EELV rockets, each one would cost less, right?
Not so fast... each one of those EELVs is practicly hand built marvel that takes weeks, or months in the case of the Delta-IV Heavy, to construct and ready for flight. Simply put, a modest increase in flight rate would not substantially lower the cost of building and flying them. Only a very large increase in flight rate would make it cheap enough per-pound to do anything shy of Fortune-500/Gov't payloads. The cost for a single Delta-IV HLV still runs north of $3,000-4,000 a pound not counting payload integration, and each one of those that flies needs four or five large, expensive rocket engines and electronics, where a "package deal" is not much of a deal.
It was somewhere said that only a ten-fold decrease in launch costs (closer to 20 likly with reduced flight sched.) versus Shuttle would make private industry move beyond comm sats... EELV is half way there, but the cost per unit since it is entirely expendable is still too great to make the last five-fold decrease. It is my opinion that this level of efficency cannot be achieved without a TSTO RLV for large (25T) payloads, or a SSTO RLV for smaller (10T) ones.
Now, there are technical advantages to using HLLV/SDV... first is that you can build almost your entire ship on the ground, so the thing does not have to be cut up into small 25-ton chunks nor the extra trouble of docking collars and latches. One big launch for the crew and logistics section, one big launch for the TMI/TLI stage, and one big launch for the lander and TEI fuel and such. Were this rocket to be built on Shuttle hardware, this flight rate is achieveable today.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Not so fast... each one of those EELVs is practicly hand built marvel that takes weeks, or months in the case of the Delta-IV Heavy, to construct and ready for flight. Simply put, a modest increase in flight rate would not substantially lower the cost of building and flying them.
Granted, but there is no incentive to invest in a manufacturing process tha woud stremline the prodction of these rockets. A factory that can produce dozens of the rockets might cost more than it is currently worth to just hand build a few at a time. There's no reason to change that equation, since producing more rockets, without the demand would increase the surplus supply.
The cost for a single Delta-IV HLV still runs north of $3,000-4,000 a pound not counting payload integration, and each one of those that flies needs four or five large, expensive rocket engines and electronics, where a "package deal" is not much of a deal.
Isn't the Shuttle $10,000 a pound? If so, how much will we really be reducing the cost even with an SDV. A SDV will still use the same infrastructure as the Shuttle, which is one of the reasons why it costs so much now.
Now, there are technical advantages to using HLLV/SDV... first is that you can build almost your entire ship on the ground, so the thing does not have to be cut up into small 25-ton chunks nor the extra trouble of docking collars and latches.
Granted. However, this continues the same problems we have now- infrequent space flights. Massive up-front budgets just to get started. Planning cycles on the order of decades. Cascade system redesign after alteration of one smaller component of the program/ship. One big roll of the dice, instead of a few smaller ones.
Which might have the better chance of being sustainable?
One big launch for the crew and logistics section, one big launch for the TMI/TLI stage, and one big launch for the lander and TEI fuel and such.
And a failure of any single launch will end the entire program, or hold us hostage like ISS is currently. The more we invest in a project, the more invested we become, and the less likely we are to be practical when the time comes (if it does).
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Isn't the Shuttle $10,000 a pound? If so, how much will we really be reducing the cost even with an SDV. A SDV will still use the same infrastructure as the Shuttle, which is one of the reasons why it costs so much now.
Each shuttle C launch should cost no more than an orbiter launch. Probably less if we exclude all orbiter reconstruction expense. But lets use orbiter launch costs.
Shuttle C can carry 3 times the mass of the orbiter, so that $10000 gets cut to $3300 right off the bat. If there are savings in flight operations by cancelling the orbiter, that figure goes down below $3300 per pound.
Shuttle C was not deployed in 1992 precisely because it would have embarassed NASA by finishing ISS too damn fast.
Right now Boeing cannot manufacture enough Delta IV barrels to sustain a robust exploration program. Before we can rely on EELV Boeing needs to build a whole new factory while we scrap the existing Morton Thiokol and Lockheed Martin facilities.
How can that be more effecient?
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SDV for cargo and EELV for crew.
Take the spare Russian ISS-Zarya module. Add one TransHab. Add a custom built re-useable lunar lander. Add aeroshell for Earth orbital capture.
Launch on shuttle C. Land on Moon. Return to the large lunar orbital module (ISS-Zarya + Transhab). Land elsewhere on moon. Return to large orbital module. Repeat until lunar lander fuel is exhausted.
Return to Earth orbit and off load moon rocks via CEV or Soyuz.
Launch 75000 kg in fuel on shuttle C. Refuel the above ships. Repeat mission.
If we cancel ISS and use STS/ISS money, we can accomplish this by 2010, no problem. Include the ISS partners as compensation for ISS cancellation.
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Shuttle C can carry 3 times the mass of the orbiter, so that $10000 gets cut to $3300 right off the bat. If there are savings in flight operations by cancelling the orbiter, that figure goes down below $3300 per pound.
Okay, but if we can move more, won't we be flying less? So that means most of the time, the space shuttle infrastructure goes idle. How is that effecient? And, if there is a failure in launch, we lose three times as much. Disaster magnified.
Then there are those times, which I have no doubt we will encounter, where we cannot send the Shuttle C up with a full basket. We save nothing in those instances. Where is the improvement?
Shuttle C was not deployed in 1992 precisely because it would have embarassed NASA by finishing ISS too damn fast.
Leave the backroom conspiracy theories outside, with the face on Mars.
"No, no, no. Too good. Slow down, you're going to make us look bad by succeeding."
Right now Boeing cannot manufacture enough Delta IV barrels to sustain a robust exploration program.
Right now, NASA can't get into space. There is no difference in either of our statements here Bill. Might it be possible, or plausible, to expect that Boeing or Lockheed, or some other upstart builds the factories if they know there is no HLLV-government-subsidized-rocket to compete with? just maybe.
An SDV now increases the likelihood that we will develop a lunar Cap Canareval. We could always develop the Ares at a later date, after, or near the end of lunar exploration. EELV would constrain the immediate future years launch capability, which might keep a lid on the size of any eventual lunar base.
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Ares will be impossible once Pad 39 is scrapped.
If all flights are on EELV, why pay to maintain Pad 39, the crawler and the VAB?
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I'm sure some group or other will band together to save it for 'memories' sake. :laugh: That and the foam. Save the Foam! Save the Foam! Don't let it fall to Earth!
Perhaps at some later date, we won't need NASA at all to build something like the Ares... if we get into the habit of purchasing our launch capability, instead of manufacturing it ourself, NASA get's back into the business of exploration, and out of business management.
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Right now Boeing cannot manufacture enough Delta IV barrels to sustain a robust exploration program. Before we can rely on EELV Boeing needs to build a whole new factory while we scrap the existing Morton Thiokol and Lockheed Martin facilities.
The limiting factor for SDV is that the Michoud plant can only build around a dozen ET's per year. However, unmanned SDV's will still be able to exceed shuttle flight rates because much of the safety checking can be skipped. Even with the manned orbiters, the space shuttles logged nine flights in 1985; I don't have any lower expectations for the SDV as long as there are enough payloads.
Who needs Michael Griffin when you can have Peter Griffin? Catch "Family Guy" Sunday nights on FOX.
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Even with the manned orbiters, the space shuttles logged nine flights in 1985; I don't have any lower expectations for the SDV as long as there are enough payloads.
After the ISS. What are the magic payloads that will keep the SDV employed? Say we had an SDV today. Say it flew 9 times in one year. Well, ISS is complete in one year (27 shuttle loads). Now what?
Wouldn't this increase the likelihood of a 'make work' program for the SDV. Discounted launch rates just to keep her flying and the staff trained? So much for private launch competition.
Then we would have this ability to put a lot of stuff in space, but nobody up there to do anything with it. We perhaps end up man-rating the SDV, just for the option of occasionaly throwing a CEV up now and then. Back to saftey checks!
And, if we accept less saftey checks, won't we encounter a higher failure rate? That's a lot of money burning up in the upper atmosphere...
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Say we had an SDV today. Say it flew 9 times in one year. Well, ISS is complete in one year (27 shuttle loads). Now what?
Yep, that is the killer argument against an SDV. Sure, if we had enough space budget to continually launch Moon and Mars missions, we'd have an acceptable launch rate. But we are not likely to have such massive budgets anytime soon.
And still, a full sequence of realistic Mars missions would only use up 2-3 SDV launches per mission. And since they would be grouped around opportune Mars launch windows, we would see some years without any SDV Mars launch.
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Right now Boeing cannot manufacture enough Delta IV barrels to sustain a robust exploration program. Before we can rely on EELV Boeing needs to build a whole new factory while we scrap the existing Morton Thiokol and Lockheed Martin facilities.
The limiting factor for SDV is that the Michoud plant can only build around a dozen ET's per year. However, unmanned SDV's will still be able to exceed shuttle flight rates because much of the safety checking can be skipped. Even with the manned orbiters, the space shuttles logged nine flights in 1985; I don't have any lower expectations for the SDV as long as there are enough payloads.
Each shuttle C can carry at least three times the payload of Delta IV, correct? 12 SDV will equal at least 36 Delta IV launches. 12 per year will be more than sufficient for a while to come.
turning to clark. . .
Wouldn't this increase the likelihood of a 'make work' program for the SDV. Discounted launch rates just to keep her flying and the staff trained? So much for private launch competition.
Elon Musk has his hands full trying to compete with Falcon, which is equivalent to Dnepr, very much smaller than even Delta. Before we turn things over to the privaet sector, maybe we should see at least some private sector success.
Anyway, I would spur private sector EELV by NOT man rating SDV. Lets see the commercial companies launch Delta II orr II or IV sized rockets before we burn the HLLV infrastructure.
As I said before, an SDV launched space hotel (unmanned, lofted with one throw) combined continuing service via Soyuz and Falcon follow ons would spur private sector development faster than anything.
Then we would have this ability to put a lot of stuff in space, but nobody up there to do anything with it. We perhaps end up man-rating the SDV, just for the option of occasionaly throwing a CEV up now and then.
Aim for 5 or 6 launches per year. Both cargo for manned missions to meet up with crew via CEV or Soyuz and also BIG unmanned probes.
Build TWO big JIMOs, or FOUR. How much more did Opportunity cost once Spirit was designed? The real cost is in the R&D not adding additional identical copies.
Back to saftey checks! And, if we accept less saftey checks, won't we encounter a higher failure rate? That's a lot of money burning up in the upper atmosphere...
Why less safety checks? Run the launch following the proven STS launch protocols. Challenger was the only launch system failure with STS and we fixed it. We solve CAIB by grounding the orbiter. Otherwise, launch shuttle C/B or Z with all the bells and whistles of any shuttle launch just NO orbiter.
It will still be far cheaper than orbiter just because of no freaking ceramic tiles to service or replace.
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Say we had an SDV today. Say it flew 9 times in one year. Well, ISS is complete in one year (27 shuttle loads). Now what?
Yep, that is the killer argument against an SDV. Sure, if we had enough space budget to continually launch Moon and Mars missions, we'd have an acceptable launch rate. But we are not likely to have such massive budgets anytime soon.
And still, a full sequence of realistic Mars missions would only use up 2-3 SDV launches per mission. And since they would be grouped around opportune Mars launch windows, we would see some years without any SDV Mars launch.
Start with the moon, then Mas, but why stop going to the moon just because we go to Mars? 2-3 for Mars & 1-2 for the Moon & 1 for robotic missions & 1 for filling an orbital fuel depot.
If there is no usable water on the Moon (hence no lunar H2 for rocket fuel) one shuttle C flight per year could carry up a tank full of rocket fuel to a fueling depot. The payload is a giant fuel tank.
Non-cryogenic fuel might be an option to avoid boil off and then large spacecraft could stay in Earth orbit for trips to the Moon and Mars and refuel without landing on Earth.
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Besides, water may well prove the radiation shield of choice. Therefore we will need lots of water in LEO and that stuff is heavy.
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If we want to do a moon base or Mars base correctly, we will have a full manifest for the SDV. The bases need to be resupplied with consumables and scientific equipment.
On the subject of safety checks, I do not advocate cutting corners with launchers, as all of them are mega-expensive pieces of machinery. I'm just saying that the level of quality assurance will always be higher with manned systems. Eliminate any need for life support or thermal protection and the burden on the shuttle team will be easier.
Who needs Michael Griffin when you can have Peter Griffin? Catch "Family Guy" Sunday nights on FOX.
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Before we turn things over to the privaet sector, maybe we should see at least some private sector success.
What kind of success do we need? They have 30+ years of experience in launching rockets. Most of the sats now in GEO or LEO were launched by private industry. The EELV for Lockheed and Boeing are little more than the same rocket systems configured differently to launch larger payloads. Even at their current performance specs, they will still need to improve the EELV (if for nothing else than to man-rate them).
So there will be investment to improve the EELV. Why is it hard to imagine that we turn to private industry to produce an HLLV when the need arises? Perhaps this is a chicken and egg situation- aerospace has been saying that they can't compete with NASA's monopoly on the HLLV. NASA says it has to have it's won HLLV becuase private industry can't provide the capability.... I'm tired of going in circles in LEO.
As I said before, an SDV launched space hotel (unmanned, lofted with one throw) combined continuing service via Soyuz and Falcon follow ons would spur private sector development faster than anything.
Great idea. But who would put something like this together? Where are they now? We have a problem getting ISS to function properly now, so I think we may be a bit off on the technological know-how-can-do for a space hotel.
Build TWO big JIMOs, or FOUR. How much more did Opportunity cost once Spirit was designed? The real cost is in the R&D not adding additional identical copies.
Okay, but you still need the upfront resources to start big space projects. Big budget requests don't sit well with Congress.
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What kind of sucess? I would like to see a private company launch a rocket that they designed and built without any government money or help that will lift at least 10MT to LEO sans packaging.
All the Delta and Atlas and other major US rockets are either derivitives of missiles built to kill the Communists or are at least partially funded by the government. This is the distinction I make for a rocket to be called "private."
I'm sure that Nasa will get help from LM/Boeing/et al if they are going to build any new rocket, but it will be paid for at least in part by government money. Private industry will help make the HLLV, but they aren't going to put up money for it.
As far as reliability goes, I would like to see a rocket like the Falcon V make a years' worth of launches at a reasonable flight rate before putting any high risk missions (basicly anything but fuel/food/water) on it.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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As far as reliability goes, I would like to see a rocket like the Falcon V make a years' worth of launches at a reasonable flight rate before putting any high risk missions (basicly anything but fuel/food/water) on it.
How can there be any reasonable flight rate if NASA has it's own bird? There is an over-abundance of launch capacity now.
Launching fuel? For whom? Food? For whom? Water? For whom? The ATV's are being built to take care of the ISS needs, which means Boeing, SpaceX, et. al., can't prove themselves in this arena.
I'm sure that Nasa will get help from LM/Boeing/et al if they are going to build any new rocket, but it will be paid for at least in part by government money. Private industry will help make the HLLV, but they aren't going to put up money for it.
So you're willing to trust them to help build an HLLV/SDV, but not build one on their own? What gives? Perhaps priavte industry won't put up the money becuase they realize it's not worth it to build their own. There are no customers if NASA has it's own bird. And you seem to accept some kind of synergy between government and industry, so why can't NASA subsidize development of a privately owned HLLV? Perhaps they might realize some patent revenue if a deal were struck in the right way...
All the Delta and Atlas and other major US rockets are either derivitives of missiles built to kill the Communists or are at least partially funded by the government. This is the distinction I make for a rocket to be called "private."
Well, I don't really care what the rockets were once used for, or what the heritage is. You accept that private industry will be used to build a government rocket, so then you must accept that they have the skill base and the ability. If so, then what would it take to get private industry to build an HLLV?
Incentive. A need with a profit margin. Lack of competition.
SDV by NASA gives none of this.
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Your post is as confusing as it is emphatic...
I don't believe that there will be any commertial-only affordable HLLV for a long time, probably long enough for the HLLV concept to become unessesarry. It is questionable enough that any corperation would foot the bill for anything big enough to build a manned installation (Delta-IV HLV/Proton).
I don't believe that any corperation will find anything to do in space profitably beyond launching small automated manufacturing gear... so, the only source of money to build an HLLV is the government's need for one to launch large componets to perform space exploration missions.
My definition of a true "commertial" launcher remains, that it would be a rocket developed in its entireity by commertial interests, unlike Delta/Atlas/Titan, for the sake of monetary profit. It is possible that such a rocket would be built on the promise of contracts with the government to use as a cargo hauler for exploration, which is why I mentioned the Falcon-V, but then it wouldn't be a true commertial launcher and I have doubts that it will work because of reliability concerns.
There is no incentive, so there will be no true commertial HLLV.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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I don't believe that any corperation will find anything to do in space profitably beyond launching small automated manufacturing gear... so, the only source of money to build an HLLV is the government's need for one to launch large componets to perform space exploration missions.
Why do we need "large" components for space exploration?
Couldn't the same result be achieved through more numerous, but smaller sized payload launches? Modular self-assembly (something we couldn't do back in the Apollo days... it would have taken to long to develop the skills and technology, and we were in a race).
If all we need to do is explore, we only need a few people to do it. We don't need to place an entire city in space, or on the moon, or on Mars. So what's the point of having an HLLV in the first place?
Again, let me stress that I see two competing archetictures for the future of space launch- smaller, priavte industry produced rockets, or larger, government produced rockets. Why should NASA pursue SDV or HLLV over utilizing the exsisting capabilities of the priavte launch industry?
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We need large componets because putting together alot of little ones is a huge pain, it is more efficent to launch large ones all at once. See Skylab. Furthermore, each componet has to be flight worthy on its own, think of all the extra mass of module bulkheads/docking equipment or the weight of many smaller tanks versus a big one for the same volume. And, not all componets can be self-docking: you can't make trusses, solar pannels, radiators, etc self docking, these would have to be ferried up with a tug of some sort, which will itself require development. And then there is the reliability concern, that you can put the whole thing together on the ground for testing before launch much more easily, that isn't as practical for small bits. Then you have to consider launch rate, that for a years' worth of Shuttle-Z launches (say, 3) you need Fifteen Delta-IV/Atlas-V HLV shots, with Forty-Five RS-68 engines for Delta or Seventy Five SRBs for Atlas-V, and thats nothing to say about the Thirty RL-10 engines...
This increases the risk of catastrophic failure of launch considerably, since none of these vehicles have engine-out capacity. Oh and then there's the cost, $200-250M a pop for a Delta-IV HLV and probably a little less for Atlas-V, which even a Shuttle-Z with a $1Bn/flight cost amoratizing development would still would be less expensive probably, since you don't have to pay to develop or launch the extra mass of your vehicle in bite-sized chunks.
There is also efficency in using SDV-HLLV or a NOVA-HLLV inherint in their size and engines... really big solid rocket boosters have a substantial advantage in moving heavy loads off the pad efficenctly, and the sheer size of the tank (8M+) means it can hold more fuel volume per tank mass, important for LH2.
Its possible that Boeing/LM can do this high flight rate if devided between them, but I have strong doubts, and this is not accounting for the mass penalty of "Legoization" of the ship which will push this figure into the 20 launches region if you have to include a tug on each flight... I think Dr. Bell mentioned that Boeing is limited to 20 Delta-IV CBCs a year and Russia can't build RD-180 engines for Atlas-V very fast.
Oh and then don't forget, that without a really dang big rocket you can't go "direct" to anywhere. Period.
Yes its possible to do PlanBush with EELV, it just isn't very wise. I shudder to think at the amount of money the gov't would have to send Boeing/LockMart's way to make it worth their while to expand the EELV plants and import RD-180 construction.
Edit: Heck, the more I think about it, developing a big ship in small pieces is silly... it would cost bucket loads of money to cut the thing up into little pieces, if for no other reason the cost of planning and packaging to put them together. ISS pieces undergo months/years of planning before astronauts go out and risk their necks to put a few bolts and wires together.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Okay, to make space exploration easier, and more efficient, we need HLLV. When are we going to need that capability? According to the current plan, sometime after 2014, when we start exploring. Ten years from now.
Now, we build an HLLV or SDV today, in 2004, we can finish the ISS much, much sooner. Then we have an HLLV, with a capability, but nowhere else to go, or nothing else to do. We spin our wheels until the CEV is developed.
ISS would be constructed, supplies would be provided by the ATV vehichles (at a fraction of the cost of an SDV or HLLV visit). The HLLV would be overkill for sending any manned missions to ISS, and if the Iran treaty is ammended, it is less of an issue.
I get the impression that most think the SDV or HLLV could be made in a couple of years, so why not wait until after the ISS is complete? Even if it's finished by 2012, there's plenty of time left to produce the SDV, or HLLV, and still retain the exsisting Shuttle infrastructure.
And, in the intervening years, perhaps some priavte concern will step forward to build an SDV or HLLV, or the exsisting EELV could advance further in their lift capacity and capability to obviate any need for NASA to build and HLLV or SDV. There seems to be few reasons why we would need to build one right now, if at all. And, if we do, we will be able to make a better determination at a later date.
If another Shuttle fails, then we have a pressing reason, one more loss, and no more Shuttle's fly. But we still have the three, so while a tough proposition, it's not impossible to finsih the mission of completing the ISS.
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Did I say we should build HLLV right now? ...Not to my knowledge. Of course we don't need to rush into the development today if there will be a big gap between ISS/Shuttle completion and Lunar missions.
Finishing ISS will have to be done by Shuttle. There really isn't a way around this, all the modules and cargo pallets are designed to ride in the Shuttle cargo bay, and so would require signifigant redesign to make them fly on any other vehicle. You would need to launch a tug too, adding to the mass considerably, since Shuttle-C/Z won't have last mile guideance.
However, Nasa seems to be moving twards the slow/steady aproach to development to hold budgets down, so if money is available to start thinking about a SDV-HLLV today, I think it should be spent, to get the program as far along as it can be before we need it.
I really don't think that any private venture (Space Island anyone?) will put up the money to build any super-heavy launch vehicle. It won't happen. There is no reason for it... there isn't even any reason for the tripple-barrel Delta-IV for commertial payloads. It will be paid for by the government and be used for the government.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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I get the impression that most think the SDV or HLLV could be made in a couple of years, so why not wait until after the ISS is complete? Even if it's finished by 2012, there's plenty of time left to produce the SDV, or HLLV, and still retain the exsisting Shuttle infrastructure.
Here is the catch. PlanBush proposes to transfer STS money to Constellation. That is how we pay for exploration.
But unless you lay off shuttle workers there really is no money to transfer. But if you lay off the shuttle workers standing army who will keep Pad 39 from rusting away? And who will we hire 10-12 years later when we want HLLV again?
2020 arrives and where are the trained workers who know how to build main tanks at Michoud? We start from scratch.
DeltaIV Super Heavy or Delta V or Atlas VI? We will need to build new launch pads and handling gear.
Zubrin designed Ares like he did so Pad39 could be used WITHOUT modification. Maybe SDV isn't the best HLLV we can imagine but we can use SDV without re-building Pad 39 infrastructure.
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To keep what existing HLLV infrastructre we now have, we must use it. As you correctly point out.
This means that PlanBush proposed return to moon by 2015-2020 is just too slow to keep America in the game.
Metaphor time - aircraft have stall speeds. Go too slow and you can't stay airborne. If slow and steady is TOO slow, all that happens is a crash.
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But unless you lay off shuttle workers there really is no money to transfer. But if you lay off the shuttle workers standing army who will keep Pad 39 from rusting away? And who will we hire 10-12 years later when we want HLLV again?
In ten to twelve years that same workforce will have retired, or be on the cusp of retiring. Same problem with either direction we pursue. If we don't find savings from the Shuttle, then there is no exploration, and then there is no need for SDV or HLLV. Period.
So where does that leave us?
Pursue EELV and small on-orbit assembly of modular components using new space tugs (which are in development) to move everything around. Build a small base on the Moon to practice living in the harshest environment possible. Use the lessons there to prepare for exploration of longer duration, and greater reach.
This constrains our development on the Moon, so it isn't Moon Base Giagantica. In order to do Mars though, we will need an SDV/HLLV of soms sort. Develop the HLLV for that purpose, not for the begining of the space exploration.
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