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Rumor has it that "Exploration Systems Mission Directorate has laid out a program that would achieve the first human lunar landing since Apollo by March 2017"
Gossip is a terrible thing :>
[color=darkred]Let's go to Mars and far beyond - triple NASA's budget ![/color] [url=irc://freenode#space] #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps] - videos !!![/url]
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Things to note...
-Griffin is getting in a hurry to get to the Moon. Probobly to minimize the chance that a future administration will decide their budget could be "better spent elsewhere."
-Griffin has apparently abandoned the SSME for TheStick. The engine would have required some modification, but its hard to believe that much. This sounds like a cost-saving measure. Or, the SSME folks really are completly incompetant, whichever.
-Griffin doesn't have to decide which engine will power the big HLLV core stage yet... maybe he is biding his time and hopping congressional support for the expensive SSME will falter, so he can swap the far cheaper RS-68 instead.
It seems unlikly that the SSME could be radically simplified to make them cheaper, and unless orders of ~10-15 units a year could greatly reduce the unit cost through economies of scale, then dumping SSME is very important to holding down launch vehicle cost.
[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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The abandoning the SSME for the J-2S might indeed be a cost saving move, but it's one for commonality of engines since as GCNR pointed out they will be used on the HLLV upper stage anyways.
I have a love hate relationship with Griffins go fast attitude, on the one hand we need to get on the moon as fast as possible so we can get on with Mars, which should have been where we started anyways. On the other hand, doing things like dropping the lCH4 requirement for the CEV is short sited. We can't start morgaging Mars to pay for the moon.
The again, I don't understand why developing the CEV for orbit is taking even as long as it is, we are litterally inventing nothing, it's just well proven, existing engineering.
In fact couldn't you just scale up the Apollo CM to 5.5M diameter and switch to modern alloys, prehaps with a larger OML angle.
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The again, I don't understand why developing the CEV for orbit is taking even as long as it is, .
see the "Griffin: ISS, Shuttle were mistakes' thread, the interview... it's just money. The ISS and STS albatross... He says it could be done much faster if they had more money... Also this 'sooner' scenario: maybe that's another way to gain more support from Congress? Saying: hey, see, we *can* do better, if we scrap some SSME pork'
They then can either say: yeah, attaboy! or panic and give more money... (or veto the sooner plan...)
doing things like dropping the lCH4 requirement for the CEV is short sited. We can't start morgaging Mars to pay for the moon.
Sigh, I feel like that too, but OTOH... Mars isn't on the drawing-boards yet. So it's a long way to start investing money in it, before it could 'pay back'
Then again... it *is* mortgageing... if they gradually start chopping the expandability... Then Mars will need another big decision for a go/no go, because it will be a big step, technology-wise, not a gradual one...
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NASA is basically trading developing the five-segment SRB, which is easy compared to modified versions of the hypra-complex SSME, whos engineers are likly unable to cope with VSE needs to make air start and cheaper versions of the engine.
See, it goes something like this... the people that build new rocket engines or modify complicated ones for NASA appear to be a weak link in VSE that Griffin is trying to minimize. When we get close to the Moon deadline, the risk of having one or two componets holding up the rest is unacceptable.
The thing we marsies need to keep in mind, that if the Moon doesn't happen, then Mars definatly isn't going to happen. Since money is tight, dropping a little Mars tech (methane rocket) to better ensure the Moon happens might be worth while.
Again, you have to think of it two ways, NASA has two accounts, one financial and one political. If they run out of either one, NASA is doomed.
The CEV isn't quite like Apollo, it will be the first manned space vehicle to be built majority from composites, has to be able to withstand reentry multiple times unlike Apollo, and so on.
[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 agree, Griffin is taking the sane approach.
Shuttle, ISS have proven to be unfeasible, largely because of too complex, hence the spiralling costs.
I'm not saying it will be easy, but it looks like he's pruning and keeping the stuff that's promising and doable w/o having to try and shoehorn unproven or overly complex tech into the program. Too many projects got axxed that way (Venturestar for instance)
It's a good thing what's happening, given the state NASA is in. Once the shuttle is mothballed, and ISS finished enough to either 'sell' or write off, it looks like there WILL be things happening out of LEO. At last.
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I agree, Griffin is taking the sane approach.
Shuttle, ISS have proven to be unfeasible, largely because of too complex, hence the spiralling costs.
I'm not saying it will be easy, but it looks like he's pruning and keeping the stuff that's promising and doable w/o having to try and shoehorn unproven or overly complex tech into the program. Too many projects got axxed that way (Venturestar for instance)
It's a good thing what's happening, given the state NASA is in. Once the shuttle is mothballed, and ISS finished enough to either 'sell' or write off, it looks like there WILL be things happening out of LEO. At last.
Well the X-33 just wasn't going to get anywhere close to the mass fraction it needed to be an SSTO. At the same time though dumping the entire program more or less because of a fabrication error that was found to be the cause of the tank failure seems very iffy to me, especially since composite tanks are going to be and important bit of hardware if we ever go down the RLV path again...The Venturestar might not have gotten to the point of being an SSTO but it would have been an excelent place to start for a TSTO.
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X-33 a debacle, that even with all the original optimistic estimates, it seems iffy that the VentureStar would have been able to carry much payload. Its a good example of NASA starting a project that is out of its reach, and hoping that the technology will catch up fast, which is pretty silly. It never would have worked, and NASA was right to cancel the program that it never should have started to begin with.
We aren't going to go down the RLV path again for a while. A long while. The USAF might to an extent, but NASA isn't going to be talking Shuttle-II for at least 25-35 years. By that time, whatever technology for composite fuel tanks we have now will probably be obsolete. Anyway, the tank that failed on X-33 was a new semi-hollow-walled honeycomb tank, regular solid composite ones work just fine.
I don't think that any SSTO vehicle powerd by rockets only of any kind is ever going to be viable, the Tiokovsky Equation is too hard to beat. Thus, the X-33/VentureStar idea was a bad one to begin with. At least, not without a radical leap forward in materials science that yeilds a massive reduction in fuel tank mass and superlight weight heat shielding.
As a TSTO, it would make much more sense. Put it on the back of a low-hypersonic carrier plane powerd by ramjets or rockets, and that would make alot more sense. Regular bell-nozzle engines, unmanned version for cargo to eliminate crew cabin volume/mass, and then you'd be talking. Of course, the carrier plane would be large cargo plane sized at least, while being twice as fast as the SR-71 Blackbird.
[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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Lunar sooner appears to be the accelerated lunar mission architecture as defined in the updated ESAS ... Spaceref has the full details here
extract:
# New accelerated approach:
* CLV: 5 segment RSRM / 1 J-2X upperstage.
* CaLV: 5 segment RSRM / 5 SSME core stage / 1 J-2X EDS stage.
* Requires development of a single upperstage engine, a single low cost SSME derivative for the CaLV core stage and a single solid rocket booster stage.
* As documented in ESAS, this concept achieves similar loss of mission / loss of crew estimates to that of the 4 segment /1 SSME concept.
The reevaluated cost and schedule to implement these changes will result in lower overall risk to the lunar mission, enabling the lunar missions sooner due to earlier development of the required hardware (fewer development steps/changes)
[color=darkred]Let's go to Mars and far beyond - triple NASA's budget ![/color] [url=irc://freenode#space] #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps] - videos !!![/url]
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Thank goodness for Michael Griffin, finally someone starting to talk some sense... Now, out with SSME, in with RS-68.
[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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Thank goodness for Michael Griffin, finally someone starting to talk some sense... Now, out with SSME, in with RS-68.
Griffin knows his stuff, he's doing some great work
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It does look as if RS-68 is in:
http://www.space.com/spacenews/business … 60320.html
And there is nothing to say that an SSME derived RS-25 can't come later. Perhaps a central SSME surrounded by RS-68s...
I too support Mike Griffin. He is the best thing to happen to NASA in two decades.
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We've seen this before publiusr, and its not a done deal yet; it would probobly take longer to build an extra-large main tank to accomodate RS-68 without payload penalty, which could be too big a risk given the incompetance of the Michoud folks, and NASA might not be allowed to summerly eliminate the SSME builders.
[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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Pratt & Whitney now produce both, so an order from NASA is something they have to fill--one good thing about Griffin keeping as much in house as he can--and away from the Primes--except ATK.
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The same company, yes, but not the same facilities... Stennis Space Center has alot to do with the SSME, and so telling congress "we don't need them anymore," especially on the hurricane-struck Lousiana coast where Stennis is located, might be politically radioactive.
[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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The same company, yes, but not the same facilities... Stennis Space Center has alot to do with the SSME, and so telling congress "we don't need them anymore," especially on the hurricane-struck Lousiana coast where Stennis is located, might be politically radioactive.
true, we must also take the re-building the coast or 'Hurricane-factor' into consideration
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