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At least IMO the article points out the confusion of the term spiral.
http://www.thespacereview.com/article/322/1]CEV: let’s try and clear this up once and for all
There has been a lot of confusion over the last few weeks on what the actual Crew Exploration Vehicle (CEV) mission is going to be. Some sources claimed that the CEV was going to be strictly an Earth-to-Moon vehicle and was not being designed to go anywhere near the ISS.
The old what if?
If the CEV turns into another OSP or X-33, it will probably be the end of NASA in its current form.
At some point soon, the Exploration Systems office is going to have to tell the contractors and the public, in plain and simple English, what it wants the CEV to do, and to present a rough schedule for accomplishing those goals.
You beat me to this post of Dinerman's essay.
One cause of http://www.thespacereview.com/article/322/1]this problem - - IMHO - - is that the Vision for Space Exploration remains astonishingly vague.
Edited By BWhite on 1108388754
Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]
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Well if we go by what is written on Spiral development,
then we would be at this point.
The Draft Statement of Work for the CEV has been issued by NASA on December 9th, 2004. One month later, NASA has issued a Draft RFP (Request For Proposal) on January 21st, 2005 for the CEV (Crew Exploration Vehicle). The Final RFP is expected on March 1st 2005.
NASA then plans to have a suborbital or an Earth orbit fly-off called Flight Application of Spacecraft Technologies (FAST) between two teams' CEV designs before September 1st 2008.
NASA will choose two main contractor teams for the flyoff. Each team will have a complete design for the CEV and its launch vehicle. The teams will also have to develop a plan for their CEV to take part in the assembly of a lunar expedition in earth orbit.
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Do you know if any CEV Companies are working on a replacment shuttle ? to carry more than 5 crew and passengers into orbit ?
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Why would they be making a replacement Shuttle? A spaceplane can't return from the Moon safely.
[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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GCNRevenger ,
What I have read the Crew Exploration Program is to develop a complete transportation program for space movement of humans from earth - to - orbit, orbit - to moon, orbit to mars, mars orbit to martian surface and beyond.
Spaceplane technologies could be used for both earth - orbit - earth and mars orbit - surface as well. I wanted to know if anyone has read any CEV Companies working on spaceplanes ?
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"Spaceplane technologies could be used for both earth - orbit - earth and mars orbit - surface as well."
No, no they can't.
-Spaceplanes can't fly in the Martian atmosphere, its too thin.
-Spaceplanes can't fly back to Earth from anywhere except LEO, their weaker heat shields can't handle it. Only capsules can.
-Spaceplanes have to carry their wings and wheels with them to wherever they are going, making them unsuitable for Lunar trips.
[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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GCNRevenger,
I asked If anyone hear of any of the CEV Contractors developing concepts for CEV with a spaceplane design.
Furthermore, GCNRevenger, I didn't ask about the use of spaceplanes as lunar lander craft, I wanted to know if anyone was designing a total transportation system for atomspheric and non-atomspheric environments other than the old capsule / lander approach.
The CEVs information I have seen is the Tourist type capsule concept for 3-8 persons for short-term duration missions. I want to know if any of the contractors are looking at large cargo, passenger and crew volume for their transportation systems.
As usual we are going to spending billions of dollars on a system that doesn't work and in the long term must be scrapped because its like using a " small boat " to try and move the a superliner of passengers, crew, cargo, and supplies to moon , mars and beyond.
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Generally I agree that a reusable spaceplane for Earth could only reach LEO, but...
Spaceplanes can't fly in the Martian atmosphere, its too thin.
Well, actually sailplanes can fly on Mars. NASA is working on one. There's a proposal for a propeller craft driven by electric motor and solar panels, like the one NASA is already flying in Earth's atmosphere. There's also a proposal for a jet engine that uses Mars CO2 as the oxidiser, it's fuelled by magnesium powder blow into the engine by nitrogen gas. There are probably other fuels that would burn with CO2, I just haven't heard of them yet. But GCNRevenger is right that such a plane could never achieve Mars orbit. In fact, the thin atmosphere of Mars makes a conventional rocket very efficient. If you want a reusable Mars shuttle, it would be based on the Delta Clipper (DC-X).
Spaceplanes can't fly back to Earth from anywhere except LEO, their weaker heat shields can't handle it. Only capsules can.
Well, actually NASA was looking at titanium shingles before silica foam tiles were proposed. When the shuttle flies belly first into the upper atmosphere, it also creates a shock wave in front of it, similar to a blunt body, that prevents the hottest part of hypersonic air from contacting it. That helps keep it cool. Modern inconel alloy would work better than titanium, the problem is the weight of such a heat shield. Inconel foil over ceramic fibre cloth with ceramic batting isn't even able to handle the heat of the Shuttle's black tiles. Inconel plate over folded inconel foil layers was proposed as the primary heat shield for the next shuttle, but it required a shallow descent to avoid as much heat as Shuttle currently takes. It would take a truly heavy heat shield to handle an interplanetary trajectory. Such a heat shield would be too heavy to be practical; an ablative heat shield would be more cost effective, and once the heat shield is consumable you might as well use the smaller mass of an expendable capsule.
Martin_Tristar, you can use reusable spacecraft for the whole trip, but you have to use purpose built craft for each leg of the journey. A spaceplane from Earth surface to LEO, then a lunar vehicle from LEO to lunar surface and back. The lunar vehicle can use aerocapture at Earth's atmosphere, but that only works if it skims the atmosphere to avoid excessive heating. For Mars use the same spaceplane to LEO, then an interplanetary vehicle to Mars orbit, then a DC-X style Mars shuttle to the surface. A reusable Mars shuttle will only be practical after infrastructure is in place on Mars to manufacture fuel. That means after a base is built, not the initial mission.
References:
http://www.astronautix.com/lvs/dcx.htm]DC-X 1/3 scale demonstrator with pictures.
http://www.astronautix.com/craft/dcy.htm]DC-Y proposed full size SSTO RLV.
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The statement of objectives includes the following DRAFT Key Performance Parameters:
3. CEV system shall integrate with the Constellation Launch Vehicle to achieve low earth orbit.
4. CEV system shall integrate with the Earth Departure Stage to achieve lunar orbit.
5. CEV system shall integrate with the Lunar Surface Access Module to achieve lunar surface mission objectives.
My assumption is that requires a single capsule to be mounted on an expendible launch vehicle, transfered to a TLI stage, then land on the lunar surface with a legged descent/ascent stage(s). Then the same capusle has to get back to Earth. Unless there's another interpretation of "integrate", this assumes an expendable capsule. Then again, if "integrate" can mean docking two vehicles in LEO to transfer crew then you could use reusable vehicles. However, all this refers to ferrying crew back and forth. To build a lunar base you need a large mass of one-way cargo. That's best accomplished by a big expendible launch vehicle, like Shuttle-C. There are other HLLVs but we have other threads to discuss them.
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The requirements are deliberately ambiguous. Notice how it says CEV system rather than CEV capsule or CEV module. Basically, the draft key performance parameters just says some part of the CEV system has to land on the Moon.
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Would it be possible to make either DC-X 1/3 scale demonstrator or the DC-Y SSTO RLV the lander for the moon or mars?
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I asked If anyone hear of any of the CEV Contractors developing concepts for CEV with a spaceplane design.
Furthermore, GCNRevenger, I didn't ask about the use of spaceplanes as lunar lander craft, I wanted to know if anyone was designing a total transportation system for atomspheric and non-atomspheric environments other than the old capsule / lander approach.
The CEVs information I have seen is the Tourist type capsule concept for 3-8 persons for short-term duration missions. I want to know if any of the contractors are looking at large cargo, passenger and crew volume for their transportation systems.
As usual we are going to spending billions of dollars on a system that doesn't work and in the long term must be scrapped because its like using a " small boat " to try and move the a superliner of passengers, crew, cargo, and supplies to moon , mars and beyond.
And what is wrong with the old capsule aproach? They work just fine, and have a proven track reccord, and will work just fine.
At the moment, nobody is even seriously contemplating a reuseable cargo launcher, be it a RLV spaceplane or DC-I style "clippership." The reason being, there is no reason for it, and the high development cost would take up all the money you would build a Lunar base or Ion tug with.
We are simply not ready for the "development" phase when we would need a real RLV to move large masses of cargo or large crews regularly... What we need to do is set up a perminant presence first with today's technology as a "beach head" of sorts, and then start thinking about an expensive RLV. This process will take some number of years, depending on where we set up at.
Sailplanes for Mars are a novel idea, but their design makes them unsuitable for launch into orbit. Big, flimsy wings, very low total mass, and so on. A Methane-powerd DC-I style rocket would be preferred for Mars.
A spaceplane able to withstand translunar velocity reentry with an ablative shield would be very difficult to build, since the hot spots would be much hotter and the pressures on the vehicle (especially wings and soft spots) would be much higher. I don't think that an ablative shield would be reliable enough. Landing gear penitrations would be hard too.
Something like that, perhaps the capsule would remain with the TEI stage in orbit (since launching TEI fuel from the Moon would be dumb) and the lander would be a seperate manned vehicle. I envision that the lander would also be the HAB, and be suited for 4-6mo of operation with one or two resupplies.
Cargo could also be sent by a pair of EELV+ vehicles carrying payload lander + TLI stage, which would save development money, but cost more per sortie then HLLV. An ion tug for later term operations that eliminates the TLI stage might bypass this problem.
[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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Surely, we're capable today of multiple, non-returnable launches of any number of uncrewed supply and/or habitat landers directly to the Moon, right now, within "walking distance" of each another. Then, under remote-presence control, with predictive nearly-realtime operation, the base could be prepared remotely to the stage where crewed landings were feasible, with plenty of pre-planned modular hardware on hand to configure returning vehicle(s) as desired to meet ongoing needs.
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I think that it is possible to land multiple landers in a fairly small area provided the lander has plenty of maneuvering fuel and radar/lidar for landing and a navigation beacon or three. Fling a few RTG-powerd navigation beacons on a Delta-II and use a radio telescope to accuratly determine their position on the surface or put a half dozen "Lunar GPS" satelites in orbit.
What isn't practical is having them build a whole base by themselves, you would need at least one manned crew to handle the more delicate assembly operations probobly.
I also bet that it would be a good idea to design a "half sized" lander small enough to deliver a small supply payload to the Moon with only one 40M launch with chemical engines... big enough for a single Mega Atlas, Delta-IV+, or Ariane-5 ECA.
[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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GCNRevenger,
The question I asked was a simple Yes or No, and if Yes the who ?
" CEV Contractors are any developing a replacement to the space shuttle or a reusable spaceplane technology "
The discussion you started regarding the differences between capsule or reusable shuttle, comes down to the tourist and immigration statement I made on another topic. The capsule is a small vehicle for up to 8 person like a mini-van / suv or other vehicles similar in size compare to a shuttle like a bus ( single deck, multi-deck or extend length ) carrying upwards of 10 times the passengers.
Secondly, to move that volume of passengers into space denotes the infrastructure requirements for that volume of passengers including living environment and work environment. Thus expanding humanity from a tourist race into space but an immigrating race into space with a permanent presence in space in a larger scale and larger infrastructure then before.
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GCNRevenger,
The question I asked was a simple Yes or No, and if Yes the who ?
" CEV Contractors are any developing a replacement to the space shuttle or a reusable spaceplane technology "
The discussion you started regarding the differences between capsule or reusable shuttle, comes down to the tourist and immigration statement I made on another topic. The capsule is a small vehicle for up to 8 person like a mini-van / suv or other vehicles similar in size compare to a shuttle like a bus ( single deck, multi-deck or extend length ) carrying upwards of 10 times the passengers.
Secondly, to move that volume of passengers into space denotes the infrastructure requirements for that volume of passengers including living environment and work environment. Thus expanding humanity from a tourist race into space but an immigrating race into space with a permanent presence in space in a larger scale and larger infrastructure then before.
In answer to your question:
Yes, but I'm not sure if it been canceled.
We have had two failed attempts with the X-33 and X-34 shuttles. Up until George Bush's declaration that we are going back to the Moon, NASA was going to have a Fly off between a Boeing version of a next generation shuttle with Lockheed version of a next generation shuttle in about 2012. Whether or not that been canceled, I don't know. Then there are several concept of what a new shuttle should look like by several people. Then we have the Russian claim to developing a shuttle. That all I know about any new shuttle either being developed or being planned.
Larry,
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Shuttle-II has been effectively axed.
[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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This is old but perhaps the best info I've seen regarding the various "spirals" that the CEV will travel.
http://prod.nais.nasa.gov/eps/eps_data/ … c]Glossery
Exploration Spiral 1 (Crew Transportation System Earth Orbit Mission) – Encompasses the capabilities necessary to insert humans into Earth orbit and return them safely to Earth, employing a post-Space Shuttle flight system. A programmatic constraint has been imposed on Spiral 1: ”NASA shall conduct the initial test flight for the Crew Exploration Vehicle before the end of the decade in order to provide an operational capability to support human exploration missions no later than 2014”. The flight elements of the Exploration Spiral 1 Crew Transportation System are the Crew Exploration Vehicle and Crew Launch Vehicle. Robotic Precursor Missions that are scheduled to launch prior to the Earth orbit demonstration of the Spiral 1 CTS are considered Exploration Spiral 1 missions.
Exploration Spiral 2 (Extended-Duration Lunar Campaign) – Encompasses the capabilities necessary to execute extended-duration human lunar exploration. Extended duration lunar missions will be 4-14 days in duration on the lunar surface, and do not require pre-deployed surface systems (e.g., Habitation Module or Surface Power). A programmatic constraint has been imposed on Spiral 2: “NASA shall conduct the first extended human expedition to the lunar surface as early as 2015, but no later than the year 2020, in preparation for human exploration of Mars and other destinations”. Robotic Precursor Missions scheduled to launch after the Spiral 1 CTS flight demonstration, and prior to the first Spiral 3 Lunar mission are considered Exploration Spiral 2 missions.
Exploration Spiral 3 (Long-Duration Lunar Campaign) – Encompasses the capabilities necessary to execute a long-duration human lunar exploration campaign. This campaign requires development of extensive surface systems (e.g., habitation and surface power system), and long-duration lunar-vicinity parking capability of the crew transportation system. Long-duration lunar missions will extend from 14-98 days. Robotic Precursor Missions that are scheduled to launch after the last Spiral 2 extended- duration lunar mission, and prior to the initial Exploration Spiral 4 mission are considered Exploration Spiral 3 missions.
Exploration Spiral 4 (Crew Transportation System Mars Flyby) – Encompasses the capabilities to conduct a Mars flyby mission using elements of the Human-Mars Crew Transportation System. Upon completion of successful Mars flyby(s), Exploration Spiral 5 will commence. Robotic Precursor Missions scheduled to launch prior to the first Human-Martian surface mission are considered Spiral 4 missions.
Exploration Spiral 5 (Human Mars Surface Campaign) – Spiral 5 encompasses the capabilities necessary to execute human Mars exploration missions. Robotic Precursor Missions scheduled to launch after the final Mars flyby mission, and prior to the start of Exploration Spiral 6 (TBD content) are considered Spiral 5 missions.
A couple of personal thoughts...
If the CEV turns out to be reusable, a handful of spiral 1 class CEV's can be used indefinitely for ISS or future space station operations for only the operations and cost of launcher.
The best way to accomplish our spiral 2 & 3 objectives maybe to just create an add-on to the spiral 1 CEV in the from of a reusable Lander. This can be left in Lunar or LEO, and refueled either by a separate cargo mission or for free once we get lunar fuel production up and running.
Spiral 4 or 5 would present a perfect opportunity to test out key technology needed in manned lander by performing sample return missions with it. Take your basic spiral 1 CEV, gut it of life support systems, and fill it with sample racks, and some method of getting the samples to the top of the stack. Add your prototype Martian lander, with whatever rover/excavator needed to collect the samples, and send it on its way. It performs its mission, blasts off, and returns to earth in the now well tested CEV, hopefully avoiding any messy Genesis repeats. You can take it one step further by adding the fuel production technology Zubrin developed, and sending it with an inflatable sample storage ship, and having it land at one spot, operate for a month gathering samples and fuel, close up shop and take off, dropping off its samples and a little bit of fuel, a land at its next spot, rinse and repeat until the next earth return window, and use the fuel you've been gathering to return to earth. You'll need an orbital or lunar facility to look at the samples, or some other lander, but that’s a small price to pay for TONS of samples from all over the planet. And when you’re all done you'll have put the Lander well through its paces.
"Yes, I was going to give this astronaut selection my best shot, I was determined when the NASA proctologist looked up my ass, he would see pipes so dazzling he would ask the nurse to get his sunglasses."
---Shuttle Astronaut Mike Mullane
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Making a reuseable lander doesn't make any sense in the near-to-mid term, since making copies of an expendable lander will be cheaper (or at least more reliable) then developing a highly reliable reuseable one and sending the fuel to launch the reuseable back into Lunar orbit following its mission. A reuseable lander doesn't make sense until there is a true RLV on the Earth end or rocket fuel is extracted from Lunar ice.
As far as using Lunar manned systems as a Mars technology demonstrator, I don't think that is going to be worth the cost of the modifications. Whatever Mars ship is built is probobly going to be entirely new, perhaps with some CEV-derived componets for landing at Earth or Mars, but will be sufficently different that using Lunar hardware for the demo doesn't make sense.
Also, I don't think we need to test an ISRU plant, its just a chemical plant and it can be tested right here on Earth just fine. Same thing with a simple nuclear reactor for power, which will also be tested on the Moon most likly. Notice how the first Lunar missions will stay no longer then two weeks? Thats how long it is between Lunar sunrise and sunset... when solar pannels work.
[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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If we use Dennis Wingo's architecture - - a staging base at L1 and a reuseable lunar lander - - then lunar LOX combined with methane or LH2 shipped to L1 would be a marvelous way to set up shuttle service to the lunar surface. Assemble Gateway with the spare FGB-2, a Bigelow inflatable, docking ports and solar panels. (I am sure someone proposed this before Wingo, but that is where I saw this most recently.)
Fly crew via CEV or Kliper or Shenzou/Soyuz to L1 Gateway Station and then shuttle crew back and forth from gateway to the lunar surface in a reuseable lunar lander.
=IF= recoverable lunar water is discovered =THEN= great!
Otherwise, fly LH2 or methane to L1 from Earth and obtain LOX from lunar regolith. (Edit: ion drive would be useful to spiral out tanks of methane or LH2 to L1)
= = =
Form follows function. Or you can reverse engineer and determine true intentions by the capabilities that are actually developed.
A commitment to finish ISS combined with a CEV design that does not allow efficient access to the Moon reveals the original true intentions of the VSE.
Edited By BWhite on 1108697436
Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]
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I'm glad to see Spirals 1 through 5 fleshed out. This is the most detail I've seen on the Spiral development plan. Taylor Dinerman at The Space Review should be pleased.
Who needs Michael Griffin when you can have Peter Griffin? Catch "Family Guy" Sunday nights on FOX.
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Nah, thats a down-the-road thing Bill. Plus, with that setup, you are relying on TLI fuel for manned/fast trips coming from Earth, rather then from the Moon where the gravity is so much weaker. Buying rockets to fling tons of fuel into LEO to push CEV (neither Klipper nor Shenzou have enough for TLI) to the Moon when you have a Lunar fuel supply for "free" doesn't make alot of sense.
Sending the Hydrogen from Earth isn't a great solution either, the tanks would have to be very bulky, and a heavy hydrogen cryogenic condenser would be a must.
FGB-2 is already called for and will be mated to the ISS, and besides, you don't need a manned space station around the Moon for a fuel depot or crew transfer. Remember, there is no such thing as a sub-billion-dollar space station.
In the short term, everything headed to the Moon is going with an expendable lander. In the medium term you start moving to ion tugs to reduce TLI fuel needs and begin harvesting tonne quantities of Lunar water (or at least LOX) for return-to-Earth fuel. Finally, you have a fuel depot at L1 or in both Earth and Lunar orbits being fed by respective RLVs (or directly in LEO) so that each ship arrives in the destination orbit with tanks dry.
Most any vehicle suited for crew for the near future will be launched by an expendable rocket and will probobly have a (semi-) expendable crew capsule vehicle. This makes sense because it can be used for early as well as middle term Lunar travel, and so we should skip the developmental investment of an intermediate "baby space plane" before moving on to a real RLV...
...if we want to develop the Moon. If we want to go to Mars, then we take the HLLV used for the Moon and start thinking NTR TLI stage and aerobrake shield.
[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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Spirals are just another term for demonstrator programs and we all know how that turns out.
spiral 1 is only to orbit and does little to promote a ship capable to go to the moon unless it is targeted for long duration as a self contained mini station. Also useful CEV spiral 1 ship by 2014 at best to start moon missions IMO a snails pace to space.
Bwhite's thoughts a page back on a L1 staging base would be more successful IMO by canablizing the ISS modules that would prove useful (So take only the US modules if the partners complain..) and moving some of them to this point with added shielding of course.
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Spacenut, being that these space ships we have will never, ever reach the Moon, then you had best get over your pesimism about "NASA development programs" being ruinous. We will have to develop a set of new space vehicles to do anything.
The whole concept of the "spiral" system is SMALL steps, to acually accomplish real work twards a goal and meet deadlines rather then trying to do the biggest and most difficult thing all at once. See F-35 development, which has thus far been a model of efficency compared to most warplane development programs, and the head of the F-35 program now works for NASA.
It is unrealistic to think about whacking old parts off the ISS and pushing them to L1 to make a new and unnessesarry space station. That would probobly be violating the international agreement on the ISS since many major componets are vital. The technical challenge at doing something like that would be very large. I am confidant that entirely new componets would be cheaper.
Bill's plan isn't very good because too much fuel would have to be lifted from Earth using expendable rockets. Early Lunar missions will carry every drop they need for the whole mission, which dictates that you must save as much as possible. In that case, skip the LEO braking burn and instead reenter directly with a capsule like Apollo. Since a capsule's operational budget will not be much greater compared a baby spaceplane on top of a Delta-IV considering its additional development costs, then a capsule system makes more sense. Aerobraking a spaceplane/transfer vehicle/etc would require a very large aerobrake shield, which would in turn expose the vehicle to too much deceleration loadings.
Until either alot of rocket fuel is available on the Moon or in LEO from a cheap-to-fly RLV, then Bill's plan does not make sense.
[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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FGB-2?
I betcha the Russians would sell it for 400 or 500 million in hard currency. Especially if we bought a Proton to lift it and another Proton (or 2?) to dock and propel it to L1.
Less than 1 billion and FGB-2 is at L-1.
Add a Bigelow inflatable and some solar panels and a docking ring.
Then do your crew transfer with Soyuz/Shenzou, Kliper or CEV.
= = =
If the first return is 2020 and its all expendables for a while thereafter NOTHING INTERESTING WILL HAPPEN until the middle of the 2030s.
Why should any of us care, except in the most hypothetical or academic manner?
Rumsfeld said it best: "We need to use the rockets (army) we have not the rockets (army) we wish we had."
Edited By BWhite on 1108735450
Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]
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