SpaceX is a go for April 30th: 1st commercial launch to space station

Discussion in 'Science and Technology' started by RAMA, Apr 17, 2012.

  1. M'Sharak

    M'Sharak Definitely Herbert. Maybe. Moderator

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  2. publiusr

    publiusr Rear Admiral Rear Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    There was an oxygen harvester called Profac: http://www.bisbos.com/rocketscience/spacecraft/profac/profac.html

    I'm not spooked by the nuclear fuel of this thing, which has to fly rather 'low' to harvest--maybe not as low as this satellite which feels enough drag to warrant fins: http://en.wikipedia.org/wiki/Gravity_Field_and_Steady-State_Ocean_Circulation_Explorer

    My fear is a repeat of the disaster caused by the poor mans Centaur:
    http://en.wikipedia.org/wiki/Briz-M http://www.satobs.org/seesat/Apr-2007/0199.html

    I seem to remember that a Briz upper stage explosion caused more debris than the Chinese ASAT test and the recent American satellite shoot-down with a Standard missile 3 combined:
    http://military.discovery.com/tv/satellite-shootdown/numbers/numbers.html

    And that wasn't even trying to be a depot. Add hypergolics to the mix with a meteoroid, and you can imagine the rest. This is the real reason I favor HLLVs. Dump all you fuel off as thrust as quickly as you can and swap sloshing fuel for inertia that can't leak. Introduce docking and refueling to a zero g environment and you are asking for trouble.
     
  3. sojourner

    sojourner Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    Yep, it's been a BIG problem on ISS and MIR.

    not.:rolleyes:

    Inertia from an HLLV can only get you so far. Eventually you need to develop refueling sources.
     
  4. Crazy Eddie

    Crazy Eddie Vice Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    Most of the inertia from HLVs is wasted on the rocket itself. Ultimately, you're stacking an extra hundred tons of rocket just to get an extra ten tons of payload into orbit; it's not getting up there all that much faster, UNLESS you count some sort of huge Earth departure stage (which is cheating, by the way).

    The only reason to use an HLV is if you don't have the patience to use cheaper EELVs to do the same job piecemeal. Thus America's first space station was built on the ground and tossed into orbit on top an HLV (Skylab on a Saturn-V). The Space Shuttle, arguably, was also an HLV if you count the mass of the orbiter as payload, but that still meant building the station piecemeal, and with the shuttle's lower payload it was essentially a highly expensive MLV.

    In the end, we no longer use HLVs to launch space stations because we've discovered that we can build larger and more efficient structures using the tinkertoy approach. The same would be true of interplanetary missions for the same basic reason: you can build a larger spacecraft with much more propellant and much better equipment if you don't have to fit the whole thing onto a single rocket.
     
  5. publiusr

    publiusr Rear Admiral Rear Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    That tinkertoy approach actually costs you more in the long run. Most missions we have now don't need assembly. It is just better to have all liquid handling done here on the ground. ISS modules are rather cramped--especially the Soviet versions. Remember, the American ISS parts werelaunched by shuttle so they are just cans--all propulsion was handled by orbiters which no longer fly.

    A couple other folks on SLS--Carolyn Porco of the Cassini mission
    http://forum.nasaspaceflight.com/index.php?topic=27703.msg848485#msg848485

    So, yes, the capability of the rocket DOES come before the mission design and the payload determination.

    http://forum.nasaspaceflight.com/index.php?topic=27703.msg848427#msg848427

    John Grunsfeld
    http://www.nature.com/news/an-astronaut-and-a-scientist-1.9835

    The other is the size of the SLS. If down the road we wanted to launch a telescope that could, for instance, study the entire energy balance of Earth with pixel sizes smaller than clouds, it would take a big telescope. With a big rocket, you can think start to think about launching big optical systems. We think of the SLS as the human spaceflight programme, but it could be hugely enabling for science.
     
  6. sojourner

    sojourner Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    incorrect.

    We don't have any missions now that require an HLV. In the long run it is cheaper to tinkertoy missions together. Economy of scale on MLV's out paces launching one or two HLV's per year pretty much any way you look at it.

    Just for example, how much mass could you put in orbit aboard Atlas 5's or Falcon 9's compared to the cost of one launch of SLS? Assuming SLS ever gets built?

    Carolyn goes on to say in the same post that "Planetary scientists want cheap rockets". Which completely conflicts with her assertion that she wants SLS sized missions.

    Heck, your quote from John Grunsfeld contradicts her quote about rocket coming before the mission. He's designing a mission (this super resolution earth telescope) before having a vehicle to lift it on.

    And neither of them seem to understand that SLS will leave no money to develop those missions they want.
     
  7. Crazy Eddie

    Crazy Eddie Vice Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    All of the Salyut space stations as well as the Mir were assembled in orbit without the aid of an orbiter. China's space station concept is similar to the Mir and calls for assembly the same way. And if you consider that Skylab required some major repairs in orbit before it could be made operational, this means that ISS is the only space station ever constructed that "required" the space shuttle orbiter for construction; all of the others employed old fashioned autonomous rendezvous using either disposable space tugs or a minimum amount of self-propulsion.

    As for the "rather cramped" ISS modules... nothing is more cramped than a non-existent module, which is exactly what NASA will have if it has to depend on HLVs just to service the station, let alone send up a crew. China and Russia both understand this, which is why China has no long-term plans to develop HLV capability and Russia wisely gave up after the N1 fiasco and has been using the Soyuz ever since.

    As far as NASA is concerned, this is true. Not because it's SUPPOSED to be this way, but because the U.S. Senate has gotten used to using space exploration has a pork barrel public works project: the rocket is designed to maximize participation by selected aerospace contractors, not with any particular mission or capability in mind.

    Really, it's like handing a car designer a set of specifications that say "It must use a GM transmission, a Ford engine and alternator, computers and electronics installed by either HP or Intel, a Sirius Satellite Radio, Eddie Bauer seats, an aluminum frame, and it must be really really big."

    We already have telescopes that can do that. The NRO has been using them for decades (in fact they have so many of them that they're giving them away) None of them require HLVs to put them into orbit.

    The Hubble telescope doesn't qualify as a "big optical system" to you? Because it does to most people, and the entire system only weighs about 12 tons, about what you could launch on an Ariane 5 or a Proton.

    The really funny thing is, if you docked those optical systems together in an array -- say, a huge fan of smaller mirror/receptors in steerable grids -- then you wouldn't have to launch the whole thing on a single rocket, you could send them a few at a time and then dock them together into an increasingly large telescope platform; the array could literally be as large as you want it to be. 12 tons or 120 tons, perfectly scalable, in addition to being much easier to repair and service. Most importantly, not requiring a $20 billion HLV to put it into orbit means it doesn't have to work perfectly the first time you put it up there, nor do you only have to settle for ONE of them.
     
  8. publiusr

    publiusr Rear Admiral Rear Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    Well the HLV isn't going to cost 20 billion. Thats a figure floated by its enemies within NASA. Also EELV launched modules will be even more cramped than Shuttle launched modules--where the shuttle did all the lofting, docking etc. HLV advocates were around long before it became pork. Selling lots of EELVs is pork too, especially if you are constantly launching say, 36 D-IV heavies or 24 F-9 heavies to do what one or two HLLVs can do. Five of them and ISS would have been finished with most of its useful life ahead of it, not behind it.

    Ares V was going to be used for a piecemeal optical system: http://up-ship.com/blog/?p=9363

    SLS can launch a goodly sized scope on one shot as well
    http://www.stsci.edu/institute/atlast/
    http://event.arc.nasa.gov/aresv/
    http://www.futureinspaceoperations.com/papers/SPIE%20Stahl%20Ares%20V.pdf
    http://www.nasa.gov/mission_pages/constellation/ares/space_telescopes.html
    http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/40727/1/JPl Pub 08-03_A.pdf

    Ms Porco from Cassini knows her stuff. Proton was a manned station launcher before placing a rover on the moon. As far as NRO giving those spysats away, you might want to look at the post of this JPL man:
    http://www.bautforum.com/showthread...tary-Is-Gifting-NASA...?p=2028241#post2028241

    More http://www.thespacereview.com/article/150/1

    This examination shows there is no significant cost savings by pursuing the use of numbers of medium-lift vehicles when compared to the development of a new, shuttle-derived heavy lift booster.

    SLS will not always be in the development phase. Remember, we sustained over 100 STS missions that were HLVs in their own right It was just 90 to 100 tons of that was the orbiter. Now it will be all payload--payloads no one thought to ask for before the capability. People want to raid SLS budgets so they can keep launching Delta II sounding rockets and are being small minded and petty. That is what Carolyn refered to. delta II launches are like lollypops an alcoholic father gives to kinds every five minutes to keep their traps shut. Better to spend that money on a filling meal at the end of the day--even if that means listening to their squawks

    http://www.wired.com/politics/law/magazine/16-10/sl_porco

    Now imagine if we had flown 100 Saturn or SLS missions instead of shuttle missions-- and imagine at what we might have up there now--maybe even something like this: http://up-ship.com/blog/?p=15169

    Nice fictional model of a shuttle:
    http://www.starshipmodeler.co/gallery15/ap_030212_usnshuttle.html
     
    Last edited: Jun 18, 2012
  9. sojourner

    sojourner Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    incorrect all current ISS components could have been launched on existing vehicles.
    24 f9H's for one or two HLLV's? The F9H will be capable of 53,000 kilograms. The SLS in it's final form will carry about 127,000kilograms. Do the math again and tell me which is cheaper per Kilo?
    Yeah, actually, it will pretty much. remind us again when the first flight of block one is? and block 2?
    Now imagine what we could have built with 1000's of cheaper launches. something like this perhaps:
    http://www.nss.org/settlement/space/oneillcylinder.htm
     
  10. Crazy Eddie

    Crazy Eddie Vice Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    It's less than the space shuttle ended up costing, even in 2012 dollars. And the space shuttle was developed with a number of specific missions in mind, its specifications developed around those missions even though half of them never materialized. The Senate Launch System is being designed with NO specific mission in mind and thus its specifications are highly nebulous and subject to random, arbitrary changes.

    In this case, it isn't a question of whether the rocket will overrun its budget by a small or huge amount. Given the political realities faced by NASA, it's a question of whether or not it will ever fly at all.

    And this makes a difference WHY? The Russians built SEVERAL space stations this way, and the Chinese are reusing that technique for Tiangong-2.

    Ironically, Skylab remains the only space station that was ever launched, fully assembled, with an HLV. This is ironic, because NASA's reliance on HLVs (the Saturn-V) and derivative technology left their space program with a gaping performance gap through which Skylab eventually crashed. And now that we are returning to HLVs for future exploration, the exact same thing is happening to the ISS: a bigger space station with a bigger performance hole, SSDD. The only difference is we now HAVE a fallback position in a fleet of proven and reliable EELVs that wouldn't take much to man-rate, plus the Falcon 9 system which has ALREADY proven its ability to send payloads to the space station. It would be cheaper and easier to evolve that existing capability to support the space station and build NEW space stations than embrace a technological pipe dream that has already proven not to work very well.

    First of all, you don't seem to understand what "pork" means, since in this case there aren't a lot of politicians slumming for ULA or SpaceX just to give them something to do. The EELVs actually have a lot of important work to do for the NRO and the JPL, as does SpaceX -- now -- have a lot of work to do for NASA. That's like saying the auto industry is pork just because the government gave them a loan.

    Second of all, your math is a little funny on this, considering 24 F9 Heavies would be worth TEN HLVs, not just one or two. If you want a better comparison, it's really more like comparing a single SLS rocket -- at its ultimate capacity of 120 tons -- to the standard Falcon 9. The SLS puts that payload into orbit for $2 billion (space shuttle pricing). The Falcon 9 puts that into orbit over ten launches for a little over $1 billion. In the end, the smaller rockets do the same job at a lower cost, with less concentration of risk for the entire payload. Moreover, splitting the payload into ten launches lets you benefit from economies of scale and you actually wind up spending LESS than the full billion when it's all said and done.

    With EELVS and replacement modules, the ISS's useful life is STILL very much ahead of it. The only reason there's any talk of retiring it is because NASA doesn't have the means to send replacement modules, nor the budget to build them, nor the political leverage to ask for more money to do so. The reason for three of these is that they have been ordered by congress to spend all of their money on an HLV that will not be operational for more than a decade.

    You're blurring the lines between EELVs and HLVs, then, considering Proton's capabilities are similar to the Delta-IV Heavy but less than predicted for the Falcon 9H. If THAT'S what you mean by HLVs, then we're already having two different conversations altogether.

    OTOH, by that definition all the "normal" HLVs currently in use would still have to build orbiting structures piecemeal, just using slightly bigger modules.

    No, they want to raid SLS budgets so they can fund SpaceX and Sierra Nevadas development of rockets and spacecraft that already exist and are far more likely to be useful in space exploration. It's the same people who crunched the numbers and figured out that the same money that is being spent on the DEVELOPMENT of the Senate Launch System could just as easily find a hundred LAUNCHES of useful payloads on the rockets we already have.

    Think of it like a family argument. Dad wants to buy a Ford-F250 Heavy Duty with a Hemi engine and customized suspension because he wants to be able to haul three months worth of groceries in a U-haul trailer (which he will ALSO have to pay for). Everyone else in the family tells him they already have a sedan and a perfectly good minivan to shop with and the money he wants to spend on a new truck could be spent elsewhere.

    It's a silly argument, because at the end of the day the only reason to buy the truck is "because it's cool!"

    For that same money you could get 1000 EELVs or Falcon-9Hs. If you're using it for building space stations or long-haul interplanetary vessels, the former is going to be a LOT more efficient in the long run, especially since an EELV can launch every 6 months from any SINGLE launch pad (and can use multiple locations without a lot of overhead) and an HLV can barely manage it once a year and can only launch from Kennedy.
     
  11. publiusr

    publiusr Rear Admiral Rear Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    "The Senate Launch System is being designed with NO specific mission in mind."

    Lunar flybys are going to be one of many missions.
    It looks like there is a push for a lunar return among many nations: http://www.thespacereview.com/article/2094/1

    Speaking at a plenary session at GLEX on May 22 that featured the leaders or other top officials of six space agencies, Popovkin suggested the Moon, and not the asteroids, was the preferred destination of the Russian space program...“I think General Popovkin’s comments this morning were on target,” Griffin said, emphasizing that he was expressing his own opinion and not speaking for anyone else, including the AIAA, where Griffin serves as president.


    "In this case, it isn't a question of whether the rocket will overrun its budget by a small or huge amount. Given the political realities faced by NASA, it's a question of whether or not it will ever fly at all."

    Well, if this really is the Senate LV as people joke--and they hold the purse-strings (not slide rules--that's MSFC), they will push on:

    http://www.nasaspaceflight.com/2012/06/sls-teams-drawing-experience-preparation-hardware-production/

    "The Russians built SEVERAL space stations this way, and the Chinese are reusing that technique for Tiangong-2."

    The Chinese modules are not really Mir Examples. Remember there were two Chinese station examples. One module will be launched by their upcoming Long March 5--these are more Shenzou based craft, so its even smaller than Mir--but they are working on HLLVs.

    "This is ironic, because NASA's reliance on HLVs (the Saturn-V) and derivative technology left their space program with a gaping performance gap through which Skylab eventually crashed."

    I was abandoning Saturn in favor of STS that really held us back.That and this push for RLVs. You might remember the 1970s Mars missions using Saturn architecture that STS gobbled up. RLVs are the technological pipe dream that has already proven not to work very well.

    "Second of all, your math is a little funny on this, considering 24 F9 Heavies would be worth TEN HLVs, not just one or two."

    Assuming the hydrogen didn't boil off from the first launches into space--making a case to keep launching? Even if it made economic sense to say, cut up the Curiosity rover and launch it on 20 or so Vanguard rockets--is that really the best thing to do? That's why Musk himself wants to build Falcon XX.


    "--an HLV that will not be operational for more than a decade." On that we will have to wait and see.

    "It's the same people who crunched the numbers and figured out that the same money that is being spent on the DEVELOPMENT of the Senate Launch System could just as easily find a hundred LAUNCHES of useful payloads on the rockets we already have."

    That was also the arguments of fans of clipper-ships who thought larger steel ships like Great Eastern were a waste. Why, you could fund lots of schooners with that money. And you could buy lots of cessnas for the price of a C-5 Galaxy. But that is short sighted.

    "It's a silly argument, because at the end of the day the only reason to buy the truck is "because it's cool!"

    That's Skylon your talking about ;)

    "EELV can launch every 6 months from any SINGLE launch pad (and can use multiple locations without a lot of overhead) and an HLV can barely manage it once a year and can only launch from Kennedy."

    Stratolaunch could do even better if Paul Allen spends some dough. But Delta has become a real pad sitter. Shuttle flew about as frequently as Delta IV, and SLS won't have that orbiter to deal with.

    As it stands, it looks like Shuttle-derived heavy lift seems secure. Obama allowed Bolden and Lori Garver (who wasn't fond of HLLVs, or so scuttlebut has it) to roll out SLS. Worse for enemies of SLS, is this quote from the article I linked to above:

    " both Griffin and Pace...are advising presumptive Republican presidential nominee Mitt Romney on space issues."


    The good thing is that Falcon's success may erode support for the Ares-I redux that is called Liberty. Dynetics, which has Griffin as an advisor, wants to build F-1 powered LFBs to replace SRBs, and also is to do work on Stratolaunch. Moreover P&W Rocetdyne is up for sale, and Bezos wanted to recover the recently discovered Saturn stages from the sea Floor. It looks like interest in larger engines is here to stay.
     
  12. sojourner

    sojourner Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    your assumption applies to the HLV as well. And the answer to your bogey man of "the hydrogen will boil off!!!!" is to launch the fuel late in the scheme of events. Regardless, your whole line of reasoning here does not address the financial benefits of launching MLVs over HLVs.
    This has nothing to do with reality. Curiousity did not launch on an HLV. If your trying to twist our "MLV is better than HLV" argument with "A smaller rocket is always cheaper" then you're not dealing with reality.
    Elon has already dismissed the powerpoint slides that were going around of "Falcon XX". They have no "FXX" in development at this time.
    By NASA's own timeline, it won't. Only 2 launches over the next decade putting an orion capsule around the moon. Those 2 missions could easily be done with 2 MLVs per mission at a small fraction of the cost.

    You want to know what the real problem with SLS is? Not that it's an HLV, but that it's the same old pork barrel jobs program NASA has been saddled with since the 70's. It will be over priced and under utilized. If NASA had been able (or wanted) to run a competition like COTS to get it built we could have had an SLS within 5 years launching at least twice per year with tons of money left over for payloads.
     
  13. Crazy Eddie

    Crazy Eddie Vice Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    NASA has no lunar flyby mission even in the planning stages that requires SLS. They're in no position to ATTEMPT to plan such a mission since 90% of the components for it aren't even on the drawing board yet (significantly, this includes the Orion's service module).

    Yes, they'll spend a lot of money building it. That doesn't mean it'll actually DO anything.

    Tiangong-1 isn't (more of a slightly scaled-down Salyut). Their plans for Tiangong-2 largely echo the Mir, though even at a slightly reduced size, this is more than can be said for NASA until at least the middle of next decade.

    In the end, so are HLVs, in this case for the same basic reason: overly-optimistic projections of utility and overly conservative projections of risk.

    Of particular note is the fact that Skylab entered orbit in a barely-functional state, one solar array lost and the other damaged and inoperable with its sun shield torn off. A team of astronauts had to be sent up to make repairs before the station was even useable; they rode into orbit on a Saturn-IB, NASA's smaller and less expensive medium-lift booster. A Saturn-V would have been massive overkill for a rescue mission to Skylab; more importantly, it probably wouldn't have been ready in time to keep the station's orbit from decaying.

    ISS uses hydrazine for reboost, not LH2. Beyond that, I don't really understand what you're talking about.

    Probably not. Which is why it's a good thing Curiosity is small enough not to require an HLV to get anywhere.

    On the other hand, if you were really strapped for cash you could split a space probe up into 20 parts and ship it to an orbiting space station, have the astronauts assemble it, strap some ion thrusters to it and send it on its merry way. Since you can also certify and test the probe in space BEFORE it leaves orbit, that would further avoid alot of the headaches that have plagued previous since missions (Phobos-Grunt's epic computer fail, or the Cassini's high-grain antenna failing to deploy properly).

    The question really is which rocket design gives you more bang for your buck. How much time and money do really save by avoiding in-space assembly? The fact that in-space assembly and in space REPAIR are related tasks -- and the fact that every space station ever flown has required a certain amount of repair/assembly after launch -- are you really saving anything at all?

    Or put that another way: if in the 1970s NASA had possessed ONLY the Saturn-V rockets as its sole means of transporting humans into space, would they have been able to salvage Skylab?

    LOL no it wasn't :lol:

    You're getting your analogies muddled up; in this case, it's more of a C-47 vs. the Spruce Goose. One is a large aircraft that is expected to carry a large amount of cargo at a low cost. The other is a RIDICULOUSLY large aircraft that can carry more cargo than you probably need for more money than you can probably afford.

    It'll take a MAJOR technological breakthrough before HLVs become in any way economical for widespread use. SLS, far from being a breakthrough, is actually a rehash of 1970s technology slightly rearranged in a new configuration just to give some aerospace contractors and their pet space capsule something to do with their spare time. It's not even a proper launch vehicle so much as it is a multi-billion dollar nostalgia project.

    "Allowed" isn't the word for it; NASA is required by law to build it. The only constant when it comes to discussing NASA's budget is that Congressional mandates and priories are subject to change without reason or logic.

    There's support for Liberty?
     
    Last edited: Jun 23, 2012
  14. publiusr

    publiusr Rear Admiral Rear Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    As for Liberty we will have to wait and see. Musk has drawn first blood and has impressed Griffin--who supports Stratolaunch--which has to be huge to have a more Falcon 5 type rocket to carry a payload just shy of R-7 Soyuz launcher--so size does matter. Remember, the DoD needs a vibrant solid fuel industry to make air-to-air missiles, surface-to-air, etc. So Solid fuel solutions are likely to be propped up.

    SLS is hardly Spruce Goose--which actually would have been a good Ekranoplan had they made if differently for wing-in-ground-effect.

    SLS will deliver a Delta IV upper stage as a payload to place articles beyond Earth orbit--and seeing that EELVs have Musk for competition, they are gradualy coming to accept heavy-lift--especially now that my home state of Alabama (home of Delta IV) has stabbed Boeing in the heart with a new Airbus plant that is coming to Mobile to make the A320neo http://blog.al.com/live/2012/06/airbus_videos_highlight_featur.html

    So right now, SLS is going to look pretty good to Boeing--so they have adopted it as their own it seems www.beyondearth.com

    There is a move to downselect to two providers to LEO, allowing NASA to focus on BEO missions with SLS and Musk taking up the slack--although he may face competition from Antares (Taurus II)
    http://www.nasaspaceflight.com/2012/06/spacex-merlin-1d-orbital-fire-aj-26-engine/

    Remember, it was The Aerospace Corporation that "participated in the planning and development of system requirements for the Evolved Expendable Launch Vehicle (EELV) program" http://en.wikipedia.org/wiki/The_Aerospace_Corporation

    Now early on, the EELV fans took shots at Ares/Constellation, and floated all this depot nonsense specifically to launch scores of EELV since the 1990's DOT.COM bubble burst and the teledesic internet in the sky deal fell through: http://en.wikipedia.org/wiki/Teledesic

    This all left the DoD saddled with two rockets--an albatross they tried to force on Griffin's neck, and a lot of people believed their hype about how NASA shouldn't be in the rocket building business, and should rely on private space manufacturers--meaning EELV.

    And then Musk came along--a true private space company. Then--all of a sudden, the Aerospace Corp--retired Blue Suiters mind you, changed their minds and said that maybe the time isn't right for true private space:
    http://spacetalknow.org/wordpress/?p=2728
    http://tweetmeme.com/story/45874774...dumps-on-commercial-crew-prospects-nasa-watch
    www.bautforum.com/showthread.php/114170-Falcon-9-Heavy-and-propellant-depots?p=1873638#post1873638

    There was talk about preserving infrastructure. In a recent column from Aviation Week and Space Technology, Musk responded with the question "Whose infrastructure are we preserving? what with Russian RD-180s, AN-124s etc.

    Now isn't that interesting? Anytime someone talks to you about costs of this or that--think about where they are coming from. When Musk launched his first rockets, the EELVs were also just getting started. Musk was forced off the coast under the aegis of "range safety"--as if an EELV couldn't have went off course and hit his rocket instead. My guess is that this was done to eat his paypal fortune alive in immense logistics costs--and to price him out of the market--so he would quit like Beal did.

    But Musk didn't. Now, seeing that the same folks who put heavy-lift down are the same folks who went after Musk--can you really believe the figures they spouted, especially now after the Druyen tanker scandal, the EELV data theft all forgotten now that Boeing and Lockmart are one big happy fleet under ULA, etc?

    The heavy lift advocates are not selling things, they are engineers too long ignored by folks who want the status quo. Musk wasn't the first. Take Bob Truax who wanted low cost big dumb boosters like Sea Dragon, that NASA called technically uninteresting
    http://www.articles.latimes.com/1985-12-08/news/vw-14582_1_backyard-rocket/2
    http://neverworld.net/truax/

    Heavy-lift supporters sound engineering arguements have for too long been ignored by 'fastter better cheaper' folks who really want smaller and expensive--or RLV fanatics who want cool spaceplanes. HLLVs are not sexy or cool--and that is why I support them.

    Musk apparently does as well
    http://www.nasaspaceflight.com/2011/06/sls-decision-nasa-two-phase-approach/

    “Falcon Heavy should not be confused with the super heavy lift rocket program being debated by the U.S. Congress,” SpaceX officially cited when revealing their Falcon Heavy launch vehicle. “That vehicle is authorized to carry between 70-130 metric tons to orbit. SpaceX agrees with the need to develop a vehicle of that class as the best way to conduct a large number of human missions to Mars.”

    So SLS hits ULA high, and Space X hits them low. No wonder the EELV folks squawk so much.
     
    Last edited: Jul 1, 2012
  15. sojourner

    sojourner Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    Good luck with SLS getting more than 4 launches in the next 20 years. That's not a space program, it's a jobs program. Meanwhile, I believe, most of the real work will end up getting done by MLVs and FH.

    And Musk may say one thing to keep NASA happy, seeing as they are a customer, but it's what he does that's important.
     
  16. Crazy Eddie

    Crazy Eddie Vice Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    SLS would have been good too if they had made it differently. For starters -- ironically -- they probably could have saved a lot of time and money by sticking with the side-mount and going with the Shuttle-C concept from the 90s; at least then the only thing they'd have to develop is a disposable orbiter that would sit where the shuttle normally would and development would be a pretty straightforward process. With all the changes that will have to be made to make this thing fly, SLS is almost a totally new launch system that is "shuttle derived" only on paper.

    It COULD, sure. at 70mt, there's a long list of things that COULD ride on the top of an SLS to do all kinds of things beyond Earth orbit. The problem isn't the skepticism that the SLS will be able to do any of these things IF it gets built. The problem is, if NASA has no long term plans to build anything that NEEDS an SLS to get into space. Even the Orion capsule is probably going to perform its first lunar flyby off the top of a Delta-IV Heavy. With the Falcon-9H coming online around that same time, it'll be a whole new design process just to find things for the SLS to do.

    That's over and done with. They're downselecting to two firms with partial funding for a third. That basically means SpaceX and Sierra Nevada with some support going to ULA for man-rating the Atlas and/or Delta, which is what NASA planned all along.

    And if they were the ONLY people interested in the concept of propellant depots, you might have a point. You're forgetting, however, where the original idea originally came from the Marshall Space Flight Center back in the 1980s as one of the possible uses for a new manned space station in Earth orbit. Actually, MSC wanted SEVERAL space stations to be built, some of which would be propellant/supply/repair depots and others would be construction yards for orbital spacecraft.

    Most of the current propellant depot proposals are coming out of industry studies focussed directly on manned space flight architecture, including NASA's own study groups.

    The talk about "preserving infrastructure" started with the retirement of the shuttle and the impending firing of the STS standing army. SpaceX is at best a sideshow in that entire discussion.

    "Just getting started" is an interesting way of glossing over the fact that the Falcon-1 was just getting out of the concept stages when the Delta-IV and Atlas-V were starting to launch operational payloads into orbit. It's not really as if anyone thought Elon Musk represented serious competition at the time, and strictly speaking, he didn't.

    Again, this has a lot more to do with the political investment in the space shuttle and the pork monkey attached to it. This, by the way, is the second time you have tried to claim the propellant depots are just a pitch by EELV fanboys as if this undermines the validity of the concept itself OR supports the case for Heavy Lift, even if it were true, and it isn't.

    Funny, since the engineers and politicians who support the SLS program were the architects of the OLD status quo vis a vis the space shuttle. They may have been many things over the years, but "ignored" is not one of them.

    Since "Faster better cheaper" is the cornerstone if affordable manned space flight, their resistance to the idea should tell you something. And the RLV crowd remains a fringe group that is not and has never been particularly influential beyond their ability to produce a dizzying number of powerpoint presentations.

    For everyone else, it's not about being sexy or cool. It's about the fact that HLVs are unneccesary for 90% of what we want to do in space, and the 10% of those tasks you can use them for can be just as easily accomplished with smaller rockets, for less money, and in a shorter amount of time.

    To dust off an earlier analogy, it's again like the argument that you need to buy a thirty ton truck for your family. "It's not sexy or cool like a sports car" isn't all that compelling an argument when it comes to discussing the utility of what you're paying for, and at the end of the day, it's just not the kind of thing you need for the kind of work you're planning to do.

    Says the man whose most immediate political enemy is the person who single handedly designed the SLS by congressional mandate.

    What else did you expect him to say?
     
  17. publiusr

    publiusr Rear Admiral Rear Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    It tells me that folks are fed up with the Dan Golden era stagnation of endless also-ran Delta II missions of the Goldin era. And six or seven Delta IV heavies will easily cost as much as a single production SLS launch--thus no savings--just overcomplicated ISS style assembly methods and other costs that go with mission complexity that HLVs eliminate. That's why engineers favor them. Take the skycrane for Curiosity. That work-around is the direct result of EELV contraints.

    On the second bit, SLS is directly necessary for what we want to do in space
    http://www.nasaspaceflight.com/2012/03/boeing-outlines-new-modulestechnologies-for-nea-missions/
    http://www.nasaspaceflight.com/2012/01/sls-exploration-roadmap-pointing-dual-mars-approach/
    http://www.nasaspaceflight.com/2012...pa-lander-capability-enceladus-sample-return/

    The first Delta IV flight won't be a flyby but a simple test to a high Earth orbit to test the heatshield.
    http://www.nasaspaceflight.com/2012/02/orion-ptv-preparing-drop-test-eft-1-orion-progress/

    Boil-off problems are not solved, and any depots are likely to be SLS launched anyway:
    http://www.nasaspaceflight.com/2011...tform-hosting-reusable-lunar-lander-proposed/


    Also remember that the larger an LV is, the greater the internal volume growth--External surface area grows with the square with volume increasing by the cube--so having large diameters, especially for hydrogen--should be encouraged:
    http://www.ncamlp.org/technology/fsw-history.html

    As it stands, we are well on our way to SLS
    http://forum.nasaspaceflight.com/index.php?topic=29193.msg918909#msg918909

    On D-IV vs Falcon heavy
    http://forum.nasaspaceflight.com/index.php?topic=29193.msg919672#msg919672

    In terms of a down select--it would actually be better if Dream Chaser and Musk got the contracts, perhaps allowing them to work together and pool money, instead of Dream Chaser being a junior partner to ULA
     
  18. Crazy Eddie

    Crazy Eddie Vice Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    Hard to be fed up with something that is no longer occurring, don't you think? That's like going to a political rally next Tuesday and saying "I'm sure we're all really fed up with Osama bin Laden."

    Then it's a good thing it only takes four of them to outperform the SLS' initial payload mass.;)

    Have been employed and proven to work on two different space stations now. The one and only time we used an HLV to throw an entire station into orbit in one sitting... guess what? It arrived in orbit barely functional and had to be rescued by an astronaut crew anyway. Interestingly, the Soviets tried the same thing with the Energia rocket, attempting to toss an entire unmanned space station in a single sitting, resulting in epic fail and the epitaph of Energia.

    Ultimately, avoiding in-space assembly doesn't save you any money, it only saves you TIME, which in the context of space flight is about the ONLY thing we have in abundance. Unless we're building a space station with the intention of fighting off a Klingon invasion next month, we can afford to take the time and split the construction up into multiple launches, which ultimately saves money AND leads to a more robust launch system that can be used to do other things.

    LOL not by a longshot. It's a result of the fact that what they're essentially trying to do is a propulsive landing on mars with a robotic vehicle the size of a jeep, without having the time or the money to develop a totally new space capsule for it to ride in (which would be neccesary if you want a propulsive landing all the way to the surface without screwing up the rover's sensors). If they waited a few years they could get Elon Musk to loan them a man-rated Dragon and launch it on a Falcon Heavy. If they waited a few years longer, they could launch it on a regular Falcon 9, and then use a second Falcon 9 to lift an ion-powered transfer stage: the entire curiosity mission at one tenth the budget.

    Only if we want to do it really quickly on a ridiculously huge budget. Either of which necessarily implies TEMPORARILY, which is exactly what we have always gotten with HLVs: very short-lived, very temporary space missions with absurdly high price tags.

    That's the problem with HLVs: with a non-infinite budget, you can't use them very often and you can't use alot of them. Your weight restrictions are actually made WORSE, because you have to fit everything you need into a single launch and if something goes wrong you won't get another chance for AT LEAST six months. Smaller launch systems can tolerate a higher flight rate, which means more on-orbit support, which means you can launch longer missions more often for less money.

    The first FLYBY probably will be as well, which is what I actually said.

    Hydrazine doesn't boil off.

    And my grandmother is likely to grow wheels and become a wagon.

    Using hydrogen for orbital propellant, however, should not. On long term missions you need a storable propellant that doesn't need babysitting; the extra isp you get from LOX/LH2 isn't all that useful in the context of orbit changes and stationkeeping (for most spacecraft, it's a difference of like 200m/s BEFORE it gets eaten up by the extra weight of the tankage). Hydrazine takes a smaller tank and less complicated engines, and you can store it for years; twenty tons of that stuff in an orbital depot could meet the needs of a hundred space probes or a thousand Hubble telescopes.

    From this you get mission flexibility: Curiosity rides up in a Falcon-9 and an astronaut crew checks it out in orbit BEFORE it leaves to make sure nothing got damaged during liftoff. And therein lies the rub: what if something DID get damaged during liftoff? Are you gonna pack up replacements and wait six months for NASA to prepare the next SLS, or are you gonna toss a repair package into orbit with the other Falcon 9 you already contracted to launch an unfueled Earth Departure Stage?

    Actually, I'm pretty sure ULA is going to wind up being the Junior Partner to Sierra Nevada; the way things are working out, NASA's mainly focussing on getting a manned spacecraft developed, not so much a man-rated ROCKET, which they see as a secondary need for commercial crew development.
     
  19. publiusr

    publiusr Rear Admiral Rear Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    I would have no problems with hydrazine depots myself. That's what von Braun wanted, but folks are really risk averse today. That Briz failure spooked a lot of people. Robustness seems key:
    http://www.nasaspaceflight.com/2012/07/nasa-safety-panel-crew-risk-mitigation-debut-sls-mission/
    http://www.nasaspaceflight.com/2012/04/sls-robust-face-scrubs-launch-delays-pad-stays/

    There is some interesting news: The stratolauncher doesn't seem to be the only air-launched concept being looked at--and I'm not just talking White Knight 2

    http://www.nasaspaceflight.com/2012/07/commercial-shows-reignited-interest-air-launch-system/

    Dream Chaser news
    www.nasaspaceflight.com/2012/07/dream-chaser-nlg-skid-system-landing-tests/

    Orion (wingless designs) capsule still best for returning from the Moon/Mars
    http://www.nasaspaceflight.com/2012/07/nasa-esd-key-orion-requirement-lunar-missions/

    Liberty has made the news again. Liberty isn't just the Ariane 5/SRB--ATK makes a near all composite capsule. Strange mid-service module cargo design here:
    http://www.nasaspaceflight.com/2012/07/atk-us-space-flight-independence-liberty/



    I wish I could believe that--but Boeing already has their own capsule that they would like to sell:
    http://www.nasaspaceflight.com/2012/05/boeings-cst-100-successful-full-landing-system-test/

    This is also to be launched by Atlas, so Dream Chaser will wind up having to deal with a conflict of interest. This is why the downselect must be Dream Chaser and Space X, in that each compliments the other. So write your Congressmen.

    Dream Chaser is profiled on page 37 of the July 2 issue of Aviation Week and Space Technology, where Mark Sirangelo was interviewed. He went so far as to say that since there are no outside investors or venture capitalists, they "carry twice the industry average in R&D budget." There is talk about their great down mass capability, their BOR-4/HL-20 legacy. They bought up a lot of equipment from elsewhere--the old American Rocket Co for the hybrid motor, and Starsys Research, MicroSat, etc.

    The braking mechanism for Curiosity is also theirs in part, so that may be a black mark if something goes wrong."Unlike Space X, which has moved as much component fabrication as possible in-house, Sierra Nevada usually goes outside for equipment it does not already manufacture." That worries me a little, in that it is always good to do things in-house so as to not open yourself up to some other companies problems--but this combination of in-house capability plus market savvy is one more reason a Space X/Dream Chaser combo is needed so as to compare notes.

    On Page 32 of the July 9 issue of AV Week, there is a nice write-up on Space X and Sea Launch, and how Boeing's all electric bus 702SP satellite bus will allow new markets for Musk, and how ULA is "essentially out of the market for Commercial launches."

    What that means is that they will be even more fierce to go after the manned capsule movement.In the UK, they wanted their own planes, like TSR-2. They got force fed the F-111 because it was to be cheaper--and wasn't. But the damage was done. I fear that ULA might try to give the old Avro Arrow treatment to Dream Chaser.

    Spaceship 2 gets a nice article on page 119 of the July 9 issue. called Final Countdown.


    More news:
    http://aviationweek.com/onspace
    http://www.aviationweek.com/Blogs.a...f385Post:3353dc03-5709-4912-b155-eda538af3f00



    That was at the end of the USSR, after the farce that was a war in Afghanistan depleted their budgets--along with the Baikal Amur Mainline. Rails ate up a lot of their budget. In late 2002, the full electrification of the Trans-Siberian Railway was at last announced--after 74 years of work. Energia was falsely blamed for the collapse of the USSR. Their attempts to match the USA in blue-water navy-to-blue water navy, Bomber-to-bomber is what broke them. Nikita wanted an all missile system--in that it would actually be cheaper. Had Energiya been built instead of N-1--or had at least been done earlier, things would have been different.


    They are going to need huge aeroshells for anything larger:
    http://www.universetoday.com/96119/...nd-landing-for-future-human-missions-to-mars/

    This earlier article I found to be funny:
    http://www.universetoday.com/7024/t...ge-payloads-to-the-surface-of-the-red-planet/

    Rob Manning the Chief Engineer for the Mars Exploration Directorate says that: “the problem is that right now the heat shield diameter for a human-capable spacecraft overwhelms any possibility of launching that vehicle from Earth....The structure would need to be about thirty to forty meters in diameter. The problem here is that large, flexible structures are notoriously difficult to control. At this point in time there are also several other unknowns of developing and using a Hypercone."

    But then he goes on to say: “Mars is really begging for a space elevator,” said Manning. “I think it has great potential. That would solve a lot of problems, and Mars would be an excellent platform to try it.

    So let me get this straight. He has already dismissed future HLLVs out of hand, but then in the same breath talks about a space elevator tens of thousands of miles tall, dwarfing any HLLV. That anti-heavy-lift mindset is what is hobbling us. An HLLV is just a water tower. The best thing is to just build an SLS replacement launcher in about 30-50 years time that is itself 30 meters across and just launch the aeroshell in one piece. Now if you think that sounds large, it is--but not compared to other things we build, like the Troll platform or Very Large Crude Carriers (supertankers)

    Heck a reusable HLLV like NEXUS has a bulkhead very broad and shallow--very like a Mars aeroshell would need to be:
    http://en.wikipedia.org/wiki/NEXUS_%28rocket%29

    Certain Shuttle-C designs had rigid aeroshells the width of an orbiter.
    www.astronautix.com/craft/otv.htm
    http://adsabs.harvard.edu/full/1992lbsa.conf...17L
    http://www.astronautix.com/craft/rideport.htm
    http://pdf.aiaa.org/preview/CDReadyMJPC2004_946/PV2004_3734.pdf


    And there are other LV designs that allow for very wide structures as payloads--at least potentially:
    www.astronautix.com/craft/bonaucer.htm

    More do-able: OTRAG
    http://www.astronautix.com/lvs/otrag.htm

    Parallel staging allowed very large payload diameters up to 30 m and thrust acceleration to be limited to a maximum of 3 g to allow lighter payload and space vehicle structures. The low cost was mainly achieved by simple design, lack of moving components, cheap commercial materials and components, and large volume production of tens of thousands CRPU's per year.

    But that would be a later step. On Page 22 of the July 2, 2012 we see an article called Going Long: One way Orion could take astronauts to Mars. "John Karas VP and general manager of Human Spaceflight at Lockheed Martin Space Systems...argues the mission would be affordable based on NASA funding history...SLS should be cheaper than a shuttle because it uses shuttle-heritage hardware in a simpler configuration." Now this would be using a halo orbit and astronauts would control rovers via telepresence.

    Maybe this will help:

    http://uah.edu/news/items/10-research/2501-slapshot-to-deep-space
    http://www.universetoday.com/95991/new-flying-tea-kettle-could-get-us-to-mars-in-weeks-not-months/
    http://www.bautforum.com/showthread...tle”-Could-Get-Us-To-Mars-in-Weeks-Not-Months
    https://plus.google.com/u/0/105704136900260060076/posts
    http://www.csnr.usra.edu/

    More on the Z-pinch
    http://nextbigfuture.com/2012/07/washington-plasma-startup-creates-euv.html#more


    My point in all this is for folks to understand that rocket size has been stagnant. In the past, engineering accelerated beyond science. The amount of brain power that went into the development of the Beagle was more than the product of any one man--and I would dare to say that Darwins discovery took less brain power than what went into that ship.

    With spaceflight, the science and engineering coupled together--but sometimes got into each others way. When Brunel came up with the Great Eastern, he thankfully didn't have an oceanographer trying to raid his budget for a smaller FLIP ship. But if the former had not come along, the latter would never have been made possible. In short, planetary scientists should stop trying to interfere with rocket growth and should embrace it. In the current political climate, getting SLS killed doesn't automatically mean you free its budget up for other things. More likely is that the equipment sets around, and the money is cut, leaving everybody sour. Congress supports SLS and will support payloads for it. People need to be thankful.
     
    Last edited: Jul 13, 2012
  20. Crazy Eddie

    Crazy Eddie Vice Admiral Admiral

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    Re: SpaceX is a go for April 30th: 1st commercial launch to space stat

    Considering your constant objections to in-space assembly, you would appear to be one of them.


    They're welcome to try, but the CST-100 -- much like the Liberty -- is really just Boeing making a play for a CCDev grant. Their spokespeople can't say two words about the CST-100 without adding "Of course, we can't do it on our own, not without some funding from NASA *ahem ahem*." Which makes it all the more mysterious when they go ahead and develop the thing anyway even though NASA hasn't actually given them any money. I'm almost beginning to believe that the spacecraft itself is just a scam and that they'll find a way to cancel/stall development as soon as NASA starts paying for it.

    It wouldn't be a conflict since ULA isn't the one controlling the contract. NASA's still holding the purse strings, so it's really just a question of which design NASA wants to put money behind. In the end, Boeing and ULA will have to go along with it or risk being sidelined in the entire project (especially since the Falcon-9 could easily be adapted as a second choice for the Dreamchaser).

    Actually, SpaceX is about the only company that manufactures all their parts in-house. That's one of the reasons people think of it as the poster child for the NewSpace movement: unlike, say, Boeing or Orbital Sciences, they're not just building on existing architecture to expand the industry, they're a wholly independent party with almost no ties to the existing political-industrial complex.

    Like I said, that's what they're trying to do with the CST-100. It hasn't been working very well because NASA doesn't have that much money to give and their objective isn't so much to steer cash towards defense contactors so much as fund the development of a working spacecraft in the shortest time possible. Boeing is on the short bus because -- evidently -- nobody at NASA believes that Boeing needs the CCDev money to build a working spacecraft.


    The budget crunch doesn't do much for the fact that their orbiting space platform tumbled out of orbit and broke up in the Earth's atmosphere hours after launch. It is the second of two datapoints demonstrating that throwing an entire space station into orbit in a single giant heave is usually a bad idea; building one piecemeal is a lot safer, a lot easier, and in the long run, a lot cheaper. This is likely to be true of manned spacecraft as well, such as the Nautilus-X concept NASA's been throwing around.

    They're going to need a hell of a lot more than an aeroshell if they're planning to top Curiosity. Again, the only reason for the sky crane concept was because putting the landing platform UNDER the rover would put the thing at risk for damage due to dust and debris being blown around by the thrusters. Anything larger will have to sit inside of a fully protected space capsule with full propulsive and maneuvering capabilities, very probably with the ability to transfer to an alternate landing site if something is wrong with the primary. At that point you're basically doing a manned mission without the men; curiosity is almost that already.

    That's not anti-heavy lift, that's pro-space elevator. Those are two completely different things; space elevator proponents dismiss rocketry IN GENERAL, even to the point of pretending it won't be needed for spacecraft already in orbit.

    Interestingly, the solution is implied in the problem: a spacecraft large enough to get to mars would need an enormous heatshield and would therefore be too large to put on an HLV. The obvious solution is to build a modular spacecraft so you can leave most of your mission mass in orbit and drop to the surface in a much smaller craft. HLVs would not be necessary for any part of this mission, and actually neither would space elevators.

    Meanwhile, someone with more vision and less HLV fanboyism can use six or seven Falcon-9s to boost a drive section, two habitat modules, two landers, and a big tank of xenon and fly the entire mission with a VASIMR. Since that craft doesn't have to burn up in the Earth's atmosphere every time it returns (assuming you planned your flight profile correctly) then it can make five trips to Mars and back before your SLS replacement even leaves the drawing board.

    And what, prey tell, are you planning to land on Mars with a 30 meter heat shield? That's like moving to a new town by loading your house onto an airplane and flying it there.

    That's because rocketry, like everything else, is an industry. And industry is driven by market forces of supply and demand.

    Rocket size has been stagnant because there is no demand for HLVs in the 70 ton class. There is a world of difference between market demand and something someone somewhere thinks would be cool to have; to wit, the reason there's no demand for HLVs is because 99% of what we're sending into orbit doesn't need to be that heavy. Even space stations can be assembled in orbit, so that's one less thing we need HLVs for. More damningly, it turns out that most of the things we THINK we need HLVs for could be accomplished just as easily with MLVs that already exist.

    The only reason the SLS even exists is because Congress ordered NASA to build it. NASA has no specific reason to build the SLS other than that Congressional fiat; what they need RIGHT NOW is an MLV and a working space transportation system, and in a world that hadn't completely lost its mind, they would have parlayed those needs into new capabilities that slowly but surely build into NEW capabilities, resulting in a robust and reliable spaceflight architecture.

    This is like Christopher Columbus refusing to sail to India unless Isabella could give him a 700 ton Carrack. "I can't sail around the world with three small boats, I need one really BIG boat to make the journey!"

    Rocket GROWTH isn't an advantage here. The gamechanger is REUSABILITY: if you can recover at least the first stage of a booster, you can cut your launch costs in half, which allows you to send more payloads more often and for a lower price. That opens the market to broader participation, which means more payloads, which means more money AND more development, which in turn means better rockets and still lower prices.

    An HLV is ENTIRELY counterproductive in that goal; it flies a tenth as often for twice the price and any reusability would actually make it MORE expensive, not less. We simply don't need bigger rockets to do useful things in space, we need a lot more of them, and for a lower price.

    That's pretty much exactly what it means, since at the moment CCDev is the ONLY alternative to the SLS program. If SLS doesn't deliver a viable transportation architecture -- and it probably won't -- then NASA's left with a very small number of high-concept missions it can't do and a very large number of near-term missions it was planning to outsource to industry anyway.

    It's also not really true to say that Congress supports the SLS. Kay Bailey Hutchinson and Ben Nelson, along with a very small number of others, support the SLS because it provides pork funds to their political sponsors. All it takes is one bad election or one lobbyist pulling out of a real-estate deal for the question to show up on the Senate floor "Why are we spending twenty billion dollars on a new rocket when we don't have a spaceship to launch on it?"
     
    Last edited: Jul 14, 2012