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Space The Almighty Buck Science

The Business Case for Reusable Launch Vehicles 232

Posted by michael from the four-thousand-dollars-per-payload-pound dept.
An anonymous reader writes "Remember the failures of "shuttle replacements" like VentureStar? A Space Review article argues that even if VentureStar succeeded technically, it and other proposed big RLVs would never have made it financially: they cost too much to develop and wouldn't have made it up through increased launches. What's the solution? The author says that suborbital RLVs, like what Carmack, Rutan, and the other X Prize contenders are working on, will create a business cycle that will eventually lead to orbital vehicles."
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The Business Case for Reusable Launch Vehicles More

The Business Case for Reusable Launch Vehicles

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  • There is no incremental development path to orbit. (Score:5, Informative)

    by Dr. Zowie ( 109983 ) * <slashdot@@@deforest...org> on Tuesday September 02, 2003 @05:14PM (#6854234)

    The problem with incremental development of RLVs is that there's a huge
    leap between the size and difficulty of putting something into space
    for five minutes (as in the current X-prize contenders) and putting it
    into orbit (as in the shuttle). That will make it difficult to evolve our
    way into a commercial space program.

    I often find myself pointing out that just getting into space isn't
    all that hard. Lifting yourself up 100km requires about a megajoule
    (that's the energy equivalent of a stick of dynamite, or about 1/12th
    of a gallon of gasoline (about 1/4 kg or 1/2 pound of gasoline), or a
    jelly doughnut, or running a hairdryer for 2 minutes) per kilogram of
    mass.

    By contrast, orbital speed is something like 7000 meters per second,
    (or 16,000 miles per hour for you provincials). Getting going that fast
    requires an additional 24 megajoules per kilogram of mass (for a total of
    25).

    In short, the difference between the amount of energy you need to
    get into orbit and just into space is a factor of 25, for the same
    mass. That ratio of 25 is about equal to the difference between the
    latent chemical energies of broccoli and gasoline.

    Except that, in the case of space travel, you better be burning
    something at least as energetic as gasoline to start with, or you'll
    never even hoist yourself up 100km.

    The way we've traditionally gotten into orbit is to concentrate the
    kinetic energy into ever smaller bits of the vehicle: you use a huge
    rocket motor and tanks to get everything started moving, then ditch the
    empty tankage and rocket motors for the first stage -- that lets you
    concentrate on moving a smaller amount of stuff even faster.

    Realistic reusable designs are usually not staged designs,
    because it's hard to recover and reuse the first stages. The problem is
    that you have to have incredibly lightweight tankage and engines to make
    everything work. But pushing stuff to lighter weight makes it more
    flimsy and less prone to being reusable. Darn.

    The VentureStar, IIRC, ran into problems with exactly this technology --
    they were using lightweight carbon fiber tanks to hold their propellant,
    and they couldn't make the tank light enough to boost itself into orbit.

    The shuttle is NOT a reusable vehicle in any but the most technical
    sense of the word: it requires constant skilled redesign and intelligent
    (rather than scripted) maintenance, and the engines have to be overhauled
    after every flight.

    • Re:There is no incremental development path to orb (Score:4, Insightful)

      by ignipotentis ( 461249 ) on Tuesday September 02, 2003 @05:25PM (#6854302)

      From my point of view, you seem to have hit the nail on the head. RLVs are something that our current energy sources just can't dream to achive. We could build the vehicle that could sustain it, but we currently have no way of powering that vehicle.

      IIRC, this is the reason behind the space elevator [space.com]. Thus, we can get into space and dock with something already in orbit. Then we can transfer to some other station where work on space only vehicles can take place. These vehicles can then take advantage of ION Propulsion [nasa.gov] since it provides a constant acceleration.

      My degree isn't in aerospace engineering, neither i have i even attempted to read futher on either of the above concepts other than a quick glimpse, but it seems to me that we are going about things in the wrong direction. I wonder what it will take to bring that revelation that suddenly changes everything?

    • That ratio of 25 is about equal to the difference between the latent chemical energies of broccoli and gasoline.

      I'd be happy with some of that space broccoli.
      <homer>Mmmmm, space broccoli...arggahgahggaagha...</homer>
    • Don't forget that all this stuff called "air" gets in the way at times. Once you're 100 km above the surface of the earth, speeding up is just a matter of pushing yourself forward; starting from the surface, you need to worry about pushing all that air out of the way.

      I don't know any sort of exact figures, but I'm sure the ratio is much less than 25:1 when you consider the energy lost to air resistance.

    • Re:There is no incremental development path to orb (Score:4, Informative)

      by Bill Currie ( 487 ) on Tuesday September 02, 2003 @05:32PM (#6854362) Homepage
      You're out a bit with that hair dryer. At 2400W (max in places like Australia and New Zealand), it takes 416 seconds to go through a MJ and 555s at 1800W (max for North America (I think: I might be wrong about the 15A)). That's not quite 7 minutes and over 9 minutes, respectively. Even then, I don't think I'd want a 1800W hair dryer pointed at me. That's no hair dryer, that's a hot-air paint stripper!!!
    • About what I thought.

      Just as the Wright Brothers did not go from the Wright Flyer directly to a 747, or even a DC-3, we cannot expect to jump from expendable rockets immediately to large orbital RLVs.

      Except suborbital rollercoasters are more like Oriville strapping Wilbur to a kite and tying it to the bumper of their pickup truck. There's no logical economic path from that to even a Wright Flyer.
    • This was an excellent post!

      It could best be summarized as: "You can't get to orbit by climbing successively taller trees."

    • The only difference between a ballistic and an orbital trajectory is tangential velocity. But you knew that.

      There *is* an incremental development path to orbit. It goes from the X-Prize / microgravity / weather-monitoring straight up / straight down shots through ballistic trajectories, each one getting more and more hang time (higher, faster) until you're in orbit.

      Why would you want to do this? Inter-continental travel. The idea's been talked about for decades. Coast-to-coast in 30 minutes. Across the At
    • How about doing Orbital Sciences Pegasus launch vehicle one better??

      The Pegasus is a small solid rocket launch vehicle that is dropped from an L-1011 - having the inital aunch at 40,000 feet and Mach 0.85 does help a wee bit. Remember, for a given Isp and payload, the propellant mass goes to the e^(delta-V) - slight reductions in delta-V can give significant reductions in propellant mass.

      Launching from 100,000 feet and Mach 3 will help even more - there was a proposal to build the third B-70 to support

  • I don't see what the problem is: (Score:5, Funny)

    by burgburgburg ( 574866 ) <splisken06NO@SPAMemail.com> on Tuesday September 02, 2003 @05:16PM (#6854243)
    We already developed the Eagle RLVs for Moonbase Alpha more over 4 years ago. Ask Commander Koenig.

  • Just give them a chance... (Score:4, Insightful)

    by Meat Blaster ( 578650 ) on Tuesday September 02, 2003 @05:16PM (#6854244)
    The only way any of us are going to have a chance to experience space travel is if space is open to commercial entities. Nobody wants to put tax money into something that we'll all benefit from, and every disaster we experience gives us cold feet and slows down the whole process.

    The types of subsidy commercial entities are able to offer to space travel are nothing to scoff at, either. I would be willing to put up with advertising on the side of a shuttle, or under an orbital satellite, or even time-limited advertisements on the moon if it meant people got to ride there for free, and people who would complain about such things are no better than the ones who won't explore the heavens and won't let anybody else do so, either.

    We've got to start looking at these alternatives if we're ever going to get anywhere.

  • Other reuseable parts (Score:3, Insightful)

    by Creedo ( 548980 ) on Tuesday September 02, 2003 @05:16PM (#6854245) Journal
    Has any thought been given to reusing the main rockets? A friend once suggested getting them into orbit and using the shell as add-on modules for a space station. It seems like it would save time and money.
    • If you're referring to the shuttle's external tank, this has been suggested in the past. The ET already makes it most of the way to orbit on its own (it burns up and is the only component that is not reused.) It wouldn't be all that hard to add a kick motor to the underside of the tank. However, the proposals never went anywhere.

    • Been done kinda, see Skylab (Score:5, Insightful)

      by MyNameIsFred ( 543994 ) on Tuesday September 02, 2003 @05:50PM (#6854464)
      This was somewhat the idea behind Skylab. They used the upper stage as the space station. However, the upper stage was converted to a space station on the ground.

      If I understand your friend, he proposes converting the upper stages in space. This would be difficult. You would need to rip out the machinery. Then if humans are to go inside, decontaminate them of any hazardous chemicals, left-over fuel, etc. Then install the equipment to turn it into something useful, which has to be brought up separately. Considering the difficulties of working in space, it is probably easier to do all of this on the ground.

      • That may also have been a reference to reusing the Shuttle external tank. That's an idea that's been kicking around for a long time. Advantages are that it's pressure-tight (duh) and is already being carried most of the way to orbit.

        Decontamination shouldn't be hard. It stores hydrogen and oxygen, it's sucked mostly dry on the way up, and you could finish the job by opening a valve or two and letting the rest be vacuumed out.

        There'd be a lot of work installing a power system and a thermal control system.

      • If I understand your friend, he proposes converting the upper stages in space. This would be difficult. You would need to rip out the machinery. Then if humans are to go inside, decontaminate them of any hazardous chemicals, left-over fuel, etc. Then install the equipment to turn it into something useful, which has to be brought up separately. Considering the difficulties of working in space, it is probably easier to do all of this on the ground.

        Which is exactly why Skylab switched from a 'wet lab' (what

    • The external fuel tanks from the shuttle - which are (almost criminally) wasted.

      They could have been left in orbit and recycled into a space station.

      But too much work and a safety hazard for NASA.

      For a sci-fi look try finding the short story "Tank Farm Dynamo" by David Brin

  • What About The Origional RLV? (Score:5, Interesting)

    by MBCook ( 132727 ) <foobarsoft@foobarsoft.com> on Tuesday September 02, 2003 @05:23PM (#6854289) Homepage
    I just saw a thing [aetv.com] on the shuttle a few days ago that aired on the History Channel [historychannel.com]. They said that the shuttle was origionaly designed to have an RLV, but it was canceled due to budget concerns. It was supposed to launch with the shuttle on it's back, and would fly up near orbit where the shuttle would detach and fly the rest of the way. The RLV would then land so that it could be used again. It looked sort of like a plane. Has anyone thought about updating the design for this thing and making it?

    The best picture I could find was this [howstuffworks.com] one on HowStuffWorks [howstuffworks.com].

    • Even more recently there was talk of a "Liquid Fueled Flyback Booster" that would replace the SRBs with (drum roll, please) liquid fueled boosters with wings that could be flown back to a computer controlled runway landing.

      Also killed due to budget.
    • Actually, yes, the shuttle was suppose to be that way, but Nixon decided that it was too much money up Front.

      [xprize.org]
      Now legendary Burt Rutan is doing it.
      I suspect that he is scaling up that design to go into orbit, bus suspect is different than knowing.

  • RLVs (Score:4, Interesting)

    by Henry V .009 ( 518000 ) on Tuesday September 02, 2003 @05:23PM (#6854290) Journal
    The one and only point of RLVs is to be cheaper than one-time use vehicles. But they aren't. The technology and the engineering just isn't there to make them so. As an idea, the RLV has been proved to be completely worthless.

    Now, it is possible through economies of scale to bring costs down a great deal. Look at what the Germans managed with the V2 rockets. But we aren't bombing England here, and there is no reason to make that expenditure right now -- certainly not for a million dollar "X-prize." And there is still no guarantee that RLVs will surpass the cost savings of one-time use vehicles.

  • It's NOT Business! (Score:5, Insightful)

    by eutychus_awakes ( 607787 ) on Tuesday September 02, 2003 @05:24PM (#6854294)
    It's imagination. The aviation industry used to have a handful of folks who could imagine and conceptualize the darndest vehicles - and a slew of brilliant engineers to turn those concepts into reality (or dis-prove the concept based on technical limitations, materiaks, etc.)

    Nowadays, money issues and the eternal pursuit of higher profit margins has forced many of the dreamers out of the big aerospace companies and into places where there simply isn't the technical base to turn their ideas into anything at all. That's where the X-Prize will hopefully bear fruit - IF (when) the prize is claimed.

    How long did it take for Trans-Atlantic airlines to start showing profits after Lindy made his flight? It's a rhetorical question, but the answer might be interesting, nonetheless.

  • This is nonsense (Score:3, Interesting)

    by Anonymous Coward on Tuesday September 02, 2003 @05:26PM (#6854304)
    I didn't read the article, because I've seen too many like it already. It is motivated by capitalist dogma. The fact is that space exploration does not make business sense. There is nothing stopping businesses from building these things right now, if the "market" could support it. The technology exists. The only way to support construction of these things right now is by government support, and the justification is not "it makes business sense", but because the knowledge gained through them is of benefit to humanity.

    What do they honestly recommend? That we wait while individuals businesses develop inferior, and largely useless, suborbital vehicles in order to "create a business cycle", when the technology to build more useful orbital vehicles exists and has for decades? It does't make economic sense, and it certainly doesn't make sense if you believe space travel is in the greater interest of humanity. Like the internet, there may be a day when space vehicles are cheap enough that building them and operating them DOES make business sense, but like the internet, it will get there through public investment, not the dogma of economic liberalism.
    • I have come around to the opinion that the current shuttle configuration doesn't make sense for a couple of reasons. One was the aforementioned fact that it was woefully underfunded in the early stages of development. Second is the paridigm that if it's reusable, it's got to have wings & a stick that someone can control. There have been some good discussions (e.g., at http://spaceflightnow.com/news/n0307/23osp/) around just using a reusable Apollo type CM with a refurbishable heat shield as an RV. N

  • Where is the "killer app" for suborbital vehicles? (Score:5, Interesting)

    by RocketRick ( 648281 ) on Tuesday September 02, 2003 @05:29PM (#6854328)
    While the article does make some good points about the high development costs, technological hurdles, and poor ROI on reusable orbital vehicles, I think that there is very little evidence of any solid business case for reusable sub-orbital vehicles. Just because it's not cost-effective to build and fly ROVs doesn't somehow make RSVs any more logical.

    As a development step leading to the next ROV, an RSV may make sense. I am the first to admit that *anything* that gets the public to refocus their attention (and money) on the pursuit of space-related technological goals is a good thing, as it will inevitably drive the aerospace industry to push the engineering envelope in many areas, particularly in materials science (things like new composites, high-temperature ceramics, etc.). Technological advancement is a worthy (and, ultimately, profitable) pursuit.

    But, in and of itself, as a "working vehicle", I can't see any suborbital spacecraft making money. There just aren't that many rich "space tourists" around to subsidize this as an industry. Suborbital vehicles are completely useless for the two main "space jobs" that countries and/or companies are willing to pay for: satellite launches and trips to the ISS.

    Low Earth Orbit (LEO) is a useful destination. If you can get "stuff" into LEO, later trips can bring more "stuff", and, if you bring enough pieces of another space ship to LEO, you can assemble them there, and can go to other places. In terms of energy, LEO is truly "halfway to anywhere". One of the (rejected for complexity and deadline reasons) proposed Apollo moon landing plans involved assembling a Earth-to-Moon ship in LEO from modules launched over a period of time using multiple smaller launchers.

    But, suborbital vehicles, by definition, can't reach LEO. Anything launched sub-orbitally *will* return to Earth, usually sooner, rather than later. There's simply no market for delivery vehicles that always bring their cargo back, and never leave it at the destination!

    Bottom line: it may make sense to use an RSV as a technology test-bed as a step on the path to developing an ROV. It makes no sense to develop an RSV as an end in itself.

  • An intersting article (Score:5, Insightful)

    by fname ( 199759 ) on Tuesday September 02, 2003 @05:29PM (#6854333) Journal
    Well, the article makes a case for how the X-prize entries could be the springboard to cheaper access to orbital space. It seems like a nice idea, but it remains to be seen if that's the direction it will go in. I'm sure the X-prize backers have in mind a scenario like that for expanding the scope of non-governmental space efforts.

    As for an RLV, it is true that only one design has ever flown; however, to give up on a whole class of vehicles when we're still on the 1st model seems very premature. Here's one remarkable fact about the Space Shuttle Columbia: their was a breach in the wing and the it was coming apart. Yet the craft (and its software) was actually able to maintain level flight until the wing actually broke off.

    Are there flaws in the shuttle? You bet. But with 125 flights under their belt, NASA has a much better idea now how to build a reliable RLV. We're a long way from an operational vehicle, but that's only because of the high cost (and subsequent low number) of tests and launches. Maybe the X-prize entrants will solve this problem, or maybe a 2nd generation RLV will make a quantum leap in improvement-- today's big, dumb boosters are a lot better than how they started out; I bet the biggest improvments were early on.

    So good luck to Armadillo and Scaled and NASA. If congress allocates the funds for NASA, I'm sure they can build a better, safer shuttle. If not, private industry will get there someday.

  • Ed lu (Score:5, Informative)

    by zaneIO ( 606505 ) on Tuesday September 02, 2003 @05:31PM (#6854346)
    Ed, one of the guys aboard the ISS currently, wrote his take on the future of spaceships [nasa.gov], which i thought was a good read.

  • Face It Chemical Rockets Suck! (Score:2, Insightful)

    by Anonymous Coward
    or Blow if you prefer, but as long as we keep using them this whole space exploration going to consist of nothing more than hop around the moon at best and a few robot probes.

    Time to start considering real concepts like Daedalus or Orion.

  • Government != Profit (Score:5, Insightful)

    by Sean80 ( 567340 ) on Tuesday September 02, 2003 @05:40PM (#6854415)
    The first thing that strikes me about this article is the difference between hauling 100kg people up into space, and hauling the makings of a 10,000 tonne orbital factory into space. Will one lead to the other? Maybe. Will suborbital microgravity testing stations lead to a factory? Maybe. It just strikes me that we're not at a stage where this sort of thing can be done profitably, no matter who you are. As I say, from a market perspective, is there a logical progression from people to factories? Is there a logical progression from single-celled organisms to a human eye? Maybe, but I sure as hell can't see it. In my view, the government has always had to subsidize this sort of development simple because it can't be profitable at this stage of our development. Sure, the US government (as one example) seems to have forgotten the value of national infrastructure when it comes to Amtrak and the airlines, but surely they can still see the political merits of having an advantage in the space race? From a business perspective, I still can only see Saturn V rockets pulling factories into space. Is there a big enough market of millionaires to subsidize the trillions of dollars of development to put real rockets back into the sky? Maybe.

    The markets which such RLVs will serve also seem to be dominated by government. Missile testing? Remove sensing? I can't remember having bought a missile or whatever the hell it is that a remote sensor gives you lately. Seems like we'll be paying for it through taxes for a long time yet.

  • Waste of time, waste of money. (Score:3, Funny)

    by Anonymous Coward on Tuesday September 02, 2003 @05:46PM (#6854442)
    Why bother? The average "joe" out there is too busy swilling back another Budweiser to wonder about the awesome phenominum found in space. No... The average "joe" want's to see Jean-Luc gun down the Borg in another episode of Star Trek.

    The earth is a penal colony for the stupid, the lazy, the criminal, and the insane. (I fall into all of the above...)

    In short, unless you plan on not coming back, don't bother trying to escape.

    ---
    Earth has no survivors. Everyone who has ever been born here, has died here.

  • Space Elevator (Score:5, Interesting)

    by mumblestheclown ( 569987 ) on Tuesday September 02, 2003 @06:00PM (#6854505)
    Or, we do what we should be doing NOW:
    1. Funding to nanotubles.
    2. Use remaining shuttle flights to build a space elevator. Low estimates put this at 6 flights - let's conservatively double this to 12.
    3. Space elevator by 2015 is a possible reality - financially and technologically.

    Roadblocks:

    • "rocket culture" at NASA
    • "astronaut culture" at NASA
    • materials science issues are quickly disappearing
    • some probability of catastrophic (not deadly, just catastrophic) failure early on. must be budgeted using real-options analysis.
    • 10-20B USD. This can easily be funded without "coalition" help. The US would soon own space like never before, as ESA's rockets would quickly look outdated.
    • Defense concerns - the notion that a space elevator is vulnerable to, say, hostile fighter planes.
    SPACE ELEVATOR NOW - it's good science, it's good policy.
    • Nobody has demonstrated a material that is remotely strong enough to build a space elevator with yet. Until I can hold a piece of it in my hand, let's not get too excited.

      Oh, and your defence concerns are bunk.

    • Re:Space Elevator (Score:5, Interesting)

      by WolfWithoutAClause ( 162946 ) on Tuesday September 02, 2003 @06:41PM (#6854713) Homepage
      Currently, nanotubes cables are not strong enough to make space elevators, they may never be for all we know. It looks promising but it's premature to start building something without all the ingredients to make the cake rise.

      The problem, as I say is the cable. The current state of the art is about 72 GPa threads multiple centimeters long. That's extremely promising. Trouble is, nobody has built a strong rope from those threads yet. Splicing normally loses 20% of the strength; pretty much we need 65 GPa strength to reach orbit- plus a safety factor; but the carbon nanotubes are really slippery right now- sticking or splicing them doesn't seem to work.

      The second problem is nearly as bad. The projected cost is maybe $20 billion (for example, nanotubes are thousands of dollars per gram, but you need ~20 tonnes for the initial 'seed' cable).

      This means that the cost of putting something up the elevator (which takes a couple of weeks anyway) is projected to be something like $500/kg (bearing in mind that the money would have to be borrowed and repaid, quite a lot of the money is repayments of the loan). That's only slightly better than a rocket can do right now- and incidentally the same nanotube technology probably allows much cheaper/better rockets to be built.

      Then there's the radiation problem- the space elevator goes all the way through the Van Allen belts and out the other side. The Van Allen belts are really nasty- the Apollo astronauts got something like 1% of a fatal dose during the few hours they took to go through them, but an elevator goes much, much, much more slowly. That means heavy shielding, but the shielding cuts into the weight that the elevator cable can carry- you're talking about a foot thickness of heavy shielding all around the elevator. So the elevator is mostly only good for freight until you have a really beefy cable (expensive), or unless you can remove the Van Allen Belts (HiVolt is one proposal to do that).

    • We have yet to make a nanotube that is a milimeter long. The space elevator needs millions of nanotubes that are 50 miles long each.

    • Cool, let's bet the farm on technology that hasn't even been developed yet! Maybe we can use cold fusion to power it. Seriously, we should be using the technology we have now, and funding the development of new technology.
    • Roadblocks:

      * "rocket culture" at NASA
      * "astronaut culture" at NASA
      * materials science issues are quickly disappearing
      * some probability of catastrophic (not deadly, just catastrophic) failure early on. must be budgeted using real-options analysis.
      * 10-20B USD. This can easily be funded without "coalition" help. The US would soon own space like never before, as ESA's rockets would quickly look outdated.
      * Defense concerns - the notion that a space elevator is vulnerable to, say,

  • Not just RLVs (Score:3, Insightful)

    by timeOday ( 582209 ) on Tuesday September 02, 2003 @06:01PM (#6854514)
    Has there ever been a business case (ie profit) for ANY manned spacecraft at all? If NASA has failed to create one even with billions in taxpayer money, it follows that a huge leap would be required to fly one for profit. So I don't find the article too surprising.

  • We're going about it wrong (Score:5, Funny)

    by confused one ( 671304 ) on Tuesday September 02, 2003 @06:05PM (#6854532)
    I say we take the aerospace guys and mix them up with the guys who build the nuclear aircraft carriers and submarines. Tell them we want a vehicle that's nuclear powered, it has to reliably go to space and back, be self-contained (no boosters, onboard repair facilities, etc.), size / weight are not a factor (more power!!! Mwuahaha), budget is unlimited.

    Then sit back and see what kind of aircraft carrier sized behemoth vehicle they come up with...

    • I say we take the aerospace guys and mix them up with the guys who build the nuclear aircraft carriers and submarines.

      No, lets swap the aerospace guys with 3D game engine designers:

      ~
      /give flight
      /give speed
      /g_gravity 0

      Esc.

  • Go Ruskies! (Score:4, Interesting)

    by WolfWithoutAClause ( 162946 ) on Tuesday September 02, 2003 @06:12PM (#6854562) Homepage
    The article makes some very good points, and the route to space that they outline is a plausible one; but they've missed one thing.It's easy to forget that the Ruskies already sell space tourism services.

    So this gives another route there- the Ruskies sell a whole bunch of space tourist seats, and grow the market organically. Now, once they've tapped out the multibillionaires, the only way to grow is to cut the launch price; to attract the slightly less rich. The Ruskies are making a pretty decent profit on this at the moment, and if they up the launch rate the cost of the vehicle comes down at about 15% cheaper every time they double production. Now the biggest market is down at about $100,000-$500,000 per trip end, and the Ruskies are well placed to capture it and make a reasonable profit- their kit is cheap, and good.

    Of course as they prove out the market, it means that competitors will be able to borrow money to start up their own businesses; at the moment few investors believe that the market is real.

    So I don't believe that the RLV market is necessary to actually get us to full-on orbital tourism for the (well-heeled) common man. But it's still a good idea, and I hope it works out too.

    • The article makes some very good points, and the route to space that they outline is a plausible one; but they've missed one thing.It's easy to forget that the Ruskies already sell space tourism services.

      It's easy to forget, because the Russians are doing no such thing.

      The seats they have 'sold' are on flights already paid for by somebody else. (Kinda like meeting an airline pilot in a bar and slipping him a $20 to get you aboard a regularly scheduled flight, one the other passengers paid for.)

  • Rockets are antiquated (Score:5, Interesting)

    by ScrewMaster ( 602015 ) on Tuesday September 02, 2003 @06:39PM (#6854704)
    Let's not forget that there are a number of potentially viable alternatives to strapping oneself to a controlled chemical explosion and hoping it gets you where you want to go.

    The mass-driver concept pioneered by MIT is one that could provide continuous access to near-Earth orbits with clockwork precision. It would be expensive to build and run, but once running would reliably put anything we want into orbit, continuously, twenty-four hours a day.

    Another possibility is the laser-launcher. A rocket fueled simply by tanks of water would be heated by a bank of ground-based lasers: the resulting superheated steam would lift the vehicle into the desired orbit. The energy to propel the spacecraft would come from the source powering the lasers, not from any chemical fuel in the vehicle itself. This system would have the advantage of not requiring massive acceleration: laser power could be modulated to provide a comparatively gentle takeoff.

    The irrational focus on self-contained launch vehicles is the problem: there are ways to get the required kinetic energy to the vehicle without an on-board fuel supply. Granted, it might take a nuclear power plant or two to run either of the above options, but that's a lot cheaper than building even a single space shuttle, much less developing and flying the current crop of pie-in-the-sky alternatives. Current estimates put the cost of a single space-shuttle launch at 1.5 billion dollars (I suspect that's conservative.)

    And hey, when one of these gound-based launching systems isn't boosting spacecraft into orbit, it can be connected to the local power grid to light homes and businesses. Sales of power to the local utilities could be used to help offset launch costs.
    • Put the reactor inside the rocket. Use it to heat the water directly.

      1) You can launch from anyplace.

      2) You can pick up fresh reaction mass pretty much anywhere, including far away from earth.

      3) The two above mean that you could make landfall on places too uncivilized to have a laser, such as Mars, and then take off again.

      4) Your nads aren't in the vicelike grip of whomever holds the "off" switch planetside.
    • The mass-driver concept pioneered by MIT is one that could provide continuous access to near-Earth orbits with clockwork precision.

      Not really practical for earth use I'm afraid. The projectiles would leave the breach doing mach 30 odd and suffer extreme ablation (i.e. tend to burn up); and generate enormous sonic booms. The electronic power handling equipment is exceedingly expensive given the most plausible technology (e.g. using silicon). It might work for getting part of the way to orbital speed, but r

      • Some people have suggested the idea of combining reusable vehicles with mass drivers. You know, launch a reusable vehicle out of a mass driver, etc...

        I feel this is completely backwards.

        Instead, I think you would get much more bang for your buck by putting a mass launcher on a reusable vehicle. Ablation at mach 30 is not such a big issue at 100,000 ft, and we already know how to build reusable vehicles (airplanes) which can go that high. If we had mountains that high, firing a mass launcher off the mou

  • Screw SSTO: Make boosters cheap (Score:3, Interesting)

    by tjstork ( 137384 ) <todd@bandrowsky.gmail@com> on Tuesday September 02, 2003 @06:57PM (#6854789) Homepage Journal

    I'm wondering if the right tack is to just make boosters cheap. It seems to me that it is fundamentally difficult, considering the requirements for reuse and reentry survivability, to make any sort of SSTO cost effective given not only today's technology, but, tomorrow's as well.

    Instead of trying to solve the hard problems via a pseudo commercial program, invest instead in the basic research for things like material sciences so that reusable space materials might be mass produced for other applications, driving down the cost of space.

    In the mean time, we should be looking at how to simplify and reduce the construction cost of rockets so they can be made cheaper - since they are throway, and, while we are at it, if we can't keep the space "capsule" itself from being throwaway, at least design rack mounted stuff so all of the expensive avionics can be swapped out into another shell.

  • The "A Rocket a Day" approach (Score:3, Interesting)

    by dublin ( 31215 ) on Tuesday September 02, 2003 @07:14PM (#6854869) Homepage
    I already wrote a comment about this under the new launch vehicle topic, but it seems to be a better fit.

    Those who haven't done so should read John Walker's (yep, the guy who wrote AutoCAD) paper written ten years ago on a different approach, one that *will* reduce the cost of spaceflight, and prove one way or the other if there is really enough commercial potential in space to build a sustainable space economy.

    Here's the link to the paper: A Rocket a Day - Keeps the High Costs Away [fourmilab.com]

    Note especially how there is valid historical documentation to support the viability of this aproach - it's not just blowing hot air, we have hard economic evidence that this both is doable and affordable.

    It's time to kill NASA and do this right. What are we waiting for?
    • Interesting ideas, but I have to question his use of the V2 as a model for mass rocketry. They were cheap, fast to build, and it only took a few people to launch one.

      Probably because the Germans didn't have human cargo that they wanted to keep alive on top of them.

  • Market Failure is the Result of Capital Failure (Score:3, Interesting)

    by Baldrson ( 78598 ) on Tuesday September 02, 2003 @07:34PM (#6855005) Homepage Journal
    It's insanely easy to open space up to frontier development. Reusable? Yes. Expendible? Yes. The issue isn't Reusable vs Expendible -- manned vs unmanned or any of the rest of it.

    Basically capital has failed to open space as a frontier due to capital welfare in the form of protection of asset concentrations paid for out of taxes on things other than asset concentrations themselves.

    The Coalition for Science and Commerce's work on space policy reform [geocities.com] and fusion policy reform [geocities.com] led to the realization that capitalization of technology required a radical restructuring of the tax code.

    The result was a white paper [laboratory...states.com] titled "A Net Asset Tax Based On The Net Present Value Calculation and Market Democracy". Essentially the biggest economic problem civilization faces is the fact that those who acquire wealth can buy political favoritism in the form of taxes on everything _but_ wealth itself. This results in everyone paying the cost (in blood and money) of defending the legal rights of asset concentrations that are untenable militarily or morally. Stated another way: Wealth is not income. Its possession isn't protected for free. That's why taxes pay for police and armies and should be based on possession of wealth rather than its transfer (or its creation).

    The fact that welfare for capital is an inescapable feature of existing political entities has created the wrong kind of economic heirarchy in the world at the wrong point in history. The insanely zero-sum mentality infecting the leadership of the world, while solar energy streams past the Earth in quantities orders of magnitude over what we could even conceive of using on Earth will be investigated by future historians as the only worth-while subject to understand of this era.

    Here are the important excerpts from the aforementioned 1992 white paper:

    The government should tax net assets, in excess of levels typically protected under personal bankruptcy, at a rate equal to the rate of interest on the national debt, thereby eliminating other forms of taxation. Creator-owned intellectual property should be exempt.

    ...With the exception of basic functions of government and the pay down of debt, the government budget should be dispersed to citizens as cash, rather than being spent in government programs or even limited in the form of vouchers. This is "market democracy" in which the citizens and their markets, rather than central planning and politics, influence the selection of goods and services to be capitalized and provided.

    ...In reality, we are surrounded by "frontiers" in many dimensions. Few have the profound implications of a physical frontier such as the American west or space, but all share in common the attribute that proprietary access to them is restricted by government so as to prevent unproductive hoarding.

    In the case of technological frontiers, this problem is solved by limiting the patent claims to 17 years. An inventor can sit on an invention doing nothing with it for up to 17 years, but beyond that time, its use cannot be inhibited by the inventor. In practice, most inventors are so eager to see their invention brought into widespread use, they endanger their own claim. The patented technique is unique among frontier claims in that it's use is not inherently limited -- techniques are not "resources", and in that it is truly the creation of the inventor -- not an emergent phenomenon of civilization and nature.

    But in other areas, such as radio frequency and orbital slots, the analogy with frontier "land" is almost perfect.

    The NAT, unlike George's land tax, makes it possible for the government to open up all frontiers to private claim and development. Claimants must simply define and register the nature of the property rights that they wish to claim so

  • Maybe we shouldn't be trying to "made it financially" and maybe we should be trying to save the human race and get another planet colonized ASAP.

    M@
  • Anybody know of a geek like us with a few hundred thousand they're willing to blow on a rapid buildup for the x-prize?

    If so, let me know. If I could find a backer, I have a plan. downes_n@REMOVESPAMMENOWbellsouth.net

  • Star Trek Future and US doing things on the cheap (Score:3, Informative)

    by gstaines ( 607930 ) on Tuesday September 02, 2003 @09:36PM (#6855718) Homepage
    Im begining to understand the importance of why there is no currency in StarTrek (next gen) at least with the federation. It would be very depressing if the bean counters had to design the Enterprise and Picard had to fill out an expense report everytime he fired a photon torpedo.

    Once upon a time the USA never had a reputation for doing things on the cheap. But today, it looks like they are trying to do everything on the cheap. (Iraq?) Seems like Washinton has been invaded by penny pinching accountants, or is it body snatchers, I cant remember.

  • Nuclear Thermal Rockets [nuclearspace.com] are the only real hope for SSTO. The challenge is doing it safely.
  • Clark Lindsey at HobbySpace [hobbyspace.com] has some detailed suggestions [hobbyspace.com] for how NASA's shuttle budget could be re-tooled to promote the growth of private space industry, and still accomplish NASA"s human spaceflight goals. He advocates sending the remaining shuttles to museums, purchasing launch services first from the Russians, at least through 2004 when new commercial launchers should be available, and investing in the suborbital RLV industry mentioned in this space review article.

    Good ideas there... any chance of it
  • No place to go, nothing to do.

    RLVs aren't enough. To get the heavy infrastructure needed to bring the kind of space facilities (housing, industrial parks, labs, support facilities) which will make space industrialization and full-time space-based research by scientists going to work in labs up there every day, space tourism other than quick up and down trips, and to make powersats workable at a reasonable price per KWh, we need something cheaper than rockets.

    We need to bring the price of getting freight i

  • It would seem to me that companies like UPS, FedEx, USPS, etc... would find the ability to ship from New York to Hong Kong in a couple hours a significant incentive to start investing in this field.

    Is it possible, say within the next ten years, to develop a suborbital shipping vehicle that can carry enough payload to make it worth thier while?

    The idea is that as the companies compete to build systems that can handle even heavier payloads, out of this should emerge a system that can also handle orbital fli

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