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Space Science Technology

SpaceShipOne Back in Action 200

Posted by michael from the extra-duct-tape-on-board dept.
JoeSilva writes "After a 3 month wait, Scaled Composites' SpaceShipOne is back in the skies above Mojave! Not only is it patched up from a failed landing gear, it's got a 'thermal protection system' installed. Looks like high temp insulation on the leading edges. Also they have a picture of it with 'the rocket motor for the flight 13p'. This was the 12th SpaceShipOne flight."
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SpaceShipOne Back in Action More

SpaceShipOne Back in Action

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  • Lucky 13? (Score:3, Insightful)

    by dont_call_me_jim ( 472330 ) on Tuesday March 16, 2004 @01:54PM (#8580740) Homepage
    So does that mean that SpaceShipOne will be making a run for the money soon?
    • if the 13th flight experiences major problems, and the pilot(s) survive heroically, Hollywood can make a movie out of it!

      Rutan, we have a problem!
      -

    • Re:Lucky 13? (Score:5, Informative)

      by jwriney ( 16598 ) on Tuesday March 16, 2004 @02:03PM (#8580838) Homepage
      Any team wanting to make an attempt must notify the X-Prize officials at least a month in advance with the launch date and location. I would assume that this information would be released with some fanfare. Since no notification has been made yet, no official flight.

      That's not to say they couldn't go to space unofficially, before going for the big money; in fact they probably will, as part of their test series.

      --riney

      • Re:Lucky 13? (Score:5, Informative)

        by ericspinder ( 146776 ) on Tuesday March 16, 2004 @02:25PM (#8581053) Journal
        Most likely they'll hit space with a lone pilot a couple of times first. Ever flight so far only has 2 in the WK and 1 in the SSO. To win the X-Prize they would need 3 people in the SSO. So far they have been playing it safe by only having just as many people as needed(as they should), I don't see any reason they'll change the play. All the test runs they are making is showing the strength of their system, if this were NASA the runs would be 6 months apart. Besides, it's not like there is any other group so close to winning the prize. Maybe some other team might just pop outta nowhere and grab that brass ring, but they would have to be awefully sneaky to do that.

        • Re:Lucky 13? (Score:3, Informative)

          by NeoThermic ( 732100 )
          We also musn't forget the conditons of winning, that the three people who go up in the first flight must do it again in three weeks from the sucessfull landing.

          With the results and proof that nothing has knocked SSO out of the contest, I do think that is perfectly possible for them to do this.

          NeoThermic

        • Three people not necessary (Score:5, Informative)

          by jmichaelg ( 148257 ) on Tuesday March 16, 2004 @03:22PM (#8581625) Journal
          To win the X-Prize they would need 3 people in the SSO.

          The ship only has to have accomodations for three people. The rules allow for substituting ballast for the passenger's weight and letting the single pilot go up alone. The relevant rule [xprize.com] is

          3. The flight vehicle must be flown twice within a 14-day period. Each flight must carry at least one person, to minimum altitude of 100 km (62 miles). The flight vehicle must be built with the capacity (weight and volume) to carry a minimum of 3 adults of height 188 cm (6 feet 2 inches) and weight 90 kg (198 pounds) each. Three people of this size or larger must be able to enter, occupy, and be fastened into the flight vehicle on Earth's surface prior to take-off, and equivalent ballast must be carried in-flight if the number of persons on-board during flight is less than 3 persons.

        • Re:Lucky 13? (Score:2, Redundant)

          by gravelpup ( 305775 )
          To win the X-Prize they would need 3 people in the SSO.

          Close but not quite. It has to be capable of carrying three, but only has to carry one, plus the equivalent weight in ballast of the two other people.

          From the X-Prize rules page [xprize.org]:

          The flight vehicle must be flown twice within a 14-day period. Each flight must carry at least one person, to minimum altitude of 100 km (62 miles). The flight vehicle must be built with the capacity (weight and volume) to carry a minimum of 3 adults of height 188 cm (6 f

    • Re:Lucky 13? (Score:2, Insightful)

      by rijrunner ( 263757 )
      The thing to keep in mind about Scaled and some of the other groups out there is that they are working on building suborbital vehicles as a goal in, and of, itself.

      Which means that the X-Prize is incidental to Scaled goals here. Scaled is getting paid on contract terms to build this vehicle and it's pretty clear that the prize is just an incidental side-issue to their planned goal. The backers had this in line a long time before X-Prize was fully funded and they did not even enter it until after the P

  • I like that... (Score:5, Funny)

    by Phillup ( 317168 ) on Tuesday March 16, 2004 @01:55PM (#8580756)
    They have a "falling bathtub mode".

    Wonder how much they could make selling rides on that thing.

  • missing flights? (Score:3, Insightful)

    by Anonymous Coward on Tuesday March 16, 2004 @01:56PM (#8580772)
    so what happened to flights 9 through 11? The flight log jumps from flight 8 (first powered) to this latest one.

    • Re:missing flights? (Score:3, Informative)

      by jnik ( 1733 )
      11P 17 Dec 03 first powered
      10G 4 Dec 03
      09G 19-Nov-03
      08G 14-Nov-03

      Maybe they've updated the page since you looked, but they're all clearly there right now.

  • For those who don't know (Score:5, Informative)

    by ferralis ( 736358 ) on Tuesday March 16, 2004 @01:58PM (#8580785) Homepage Journal
    the "P" stands for Powered... looks like they're tipping their hand and the next flight will be with boost!

    WOOHOO!!!

    Check out the test updates here. [scaled.com]

    AFAIK, these guys are the closest to winning the X-Prize- go team!!!

  • Photos (Score:5, Informative)

    by bobthemuse ( 574400 ) on Tuesday March 16, 2004 @01:58PM (#8580786)
    A great set of photos (hopefully soon to be mirrored) is available here [scaled.com].

  • Minimal info (Score:5, Interesting)

    by apsmith ( 17989 ) * on Tuesday March 16, 2004 @01:58PM (#8580788) Homepage
    Looks like the flight was a few days ago (March 11) - why is this the first report? They're being very quiet about this. And how did Joe Silva track this down?

    • Re:Minimal info (Score:2, Insightful)

      by ferralis ( 736358 )
      He's probably doing the same thing I am- hitting their site periodically for an update.

    • Re:Minimal info (Score:5, Insightful)

      by SeaDour ( 704727 ) on Tuesday March 16, 2004 @02:08PM (#8580893) Homepage
      To say they're "being very quiet about this" is an understatement. They didn't even announce the project until well after it had gone through the design and prototype phases. Additionally, the test flights have usually been announced and discussed at least a week after their occurance. Also, we're still not even sure who all the investors in the project are. I would guess that the main reason they're keeping it so secretive is to prevent other teams from gaining the upperhand.
      • Being a private organization, Scaled is under no onus to release, announce, or update anything. Folks often seem to forget this.

  • Global Flyer (Score:5, Interesting)

    by stoolpigeon ( 454276 ) <bittercode@gmail> on Tuesday March 16, 2004 @01:59PM (#8580804) Homepage Journal
    While you are there check out the Global Flyer [scaled.com] It is just as cool in my book. The similarity in the designs of the craft are interesting. The idea of flying around the world on one tank of gas is pretty wild.

    • Re:Global Flyer (Score:5, Informative)

      by CXI ( 46706 ) on Tuesday March 16, 2004 @02:16PM (#8580982) Homepage
      Dick Rutan did a similar flight with two pilots back in 1986 with Voyager. [dickrutan.com]

      Talk about similar designs... Burt Rutan designed Voyager. :)
      • That is totally cool. I bumped into the global flyer checking up on the space ship progress last week. I didn't even know about Voyager. Kind of takes a little of the wow factor out of Global Flyer for me, seeing as they did it 18 years ago. Thanks for pointing that out.

        • This one is to be flown by a single pilot, so it has a jet engine to make it faster, but they still expect it to take 3 days. I don't know how much auto pilot they expect to use, but it won't be nearly as much an achievement if they use it at all. That would almost turn it into nothing but a drone.

        • Re:Global Flyer (Score:3, Informative)

          by Phurd Phlegm ( 241627 )
          Voyager is at the National Air and Space Museum--hanging from the ceiling. It is a pretty spectacular sight. Here's a link [si.edu] to their article about it, and another to the museum [si.edu]. It's one of the only places I'd ever bother going in Washington D.C....

      • Re:Global Flyer (Score:3, Interesting)

        by SB9876 ( 723368 )
        Just a wierd little anecdote:
        My father was working as a welder on a solar collector project back around at the time down in the Mojave desert. Since the rest of the family was back in Montana, he had lots of free time and would pass the time by driving around the area.

        One day, he happened across Scaled Compsites. He had heard of them from their work on the EZ-flyer and other projects. So, he just got out of his truck and proceeded to wander into a hanger. A couple guys looked up from their work but did

  • Armadillo Aerospace (Score:5, Insightful)

    by Sparky77 ( 633674 ) on Tuesday March 16, 2004 @01:59PM (#8580808) Homepage
    I've been following the X-Prize work at Armadillo [armadilloaerospace.com] for the last year or so. If nothing else than for the John Carmack factor. They seem to have stalled lately, always reengineering their rocket motors and such. I'm still cheering them on anyway though I can't see them surpassing Scaled Composites at this point.

    • Re:Armadillo Aerospace (Score:5, Interesting)

      by AKAImBatman ( 238306 ) <<moc.liamg> <ta> <namtabmiaka>> on Tuesday March 16, 2004 @02:29PM (#8581082) Homepage Journal
      I wouldn't worry too much. Rutan seems to be putting on a show more than actually at a "space capable" stage. IIRC, the X-Prize requires that the craft reach 100KM. Rutan's craft has only reached ~14Km, about where a 747 flies. Actual LEO is really 200km - 1500km.

      FWIW, it looks like Carmack is taking the time to understand his engines before shooting them off and hoping they fly. This is particularly important since his Monoprop fuel has an Isp of a mere 160. (Shuttle SRBs get 250, and LHOx like the Shuttle main engines get 450.)
      • A show? Was it "just a show" when the space shuttle Enterprise began drop tests [nasa.gov] from the 747 Shuttle Carrier Aircraft to validate its performance on final approach and landing?

        Tests of this type are very important. If it weren't for the 5th and final ALT test, the first flight crew (Young and Crippen aboard Columbia for STS-1) might have found themselves in a pilot-induced oscillation [nasa.gov] and crashed on landing, which would have been disastrous and delayed the program even more than it had been by that point -
        • My point is not that these aren't necessary tests. But Rutan's tests are obviously much more showy than Armadillo's. This leads people to the impression that Rutan is very near to achieving the X-Prize. The truth of the matter is that they are both in similar stages of development, albeit with different designs.
          • A glider like this one is going to require a different kind of test regime than a pure rocket is, and large flying things tend to be more noticeable to the public. All kinds of static rocket tests are carried out for all kinds of programs (one of the STS-114 SRBs got ground-test-fired this year to see how it stood up to a long wait on the pad, for instance) yet few make regular news. I think a lot of the "show" factor is coming from what the press does and doesn't find worth bothering with. Maybe not all, b

      • Re:Armadillo Aerospace (Score:4, Informative)

        by Ephboy ( 761440 ) on Tuesday March 16, 2004 @03:25PM (#8581688)
        According to their flight log: Motor light off was achieved at 44,400 feet and 0.55M. Burnout occurred at 1.2M and apogee was 67,800 feet. The max specs for a 747 are ~45,000 ft. Yes, they've got a bit more to go, but the 67,800 ft was on their first test of the engine. I'm sure they could have let it go longer and easily gotten higher.
        • My apologies. He's made it ~20km, giving a net powered flight of 6km. That leaves him about 80km to go. Hope he packed some extra fuel.
        • I believe one of the picture annotations says that they dumped their oxidizer once they hit their target altitude. Perhaps they were out of fuel, but that made me think they had fuel and dumped for safety reasons before they could land.
      • If I was John Carmack and was serious about winning the X-prize, I would be very worried about Rutan & his SS1. True, Rutan only got 14Km, but that is the whole point of a test campaign: you get to your goal in small steps. And how heigh did Carmack got by now?

        Don't understand me wrong: I don't have anything against Carmack and I think it's great what he is doing. From a betting perspective, however, who would you put your money on: a game developer with lot of creativity and spare time, or a company le

      • Umm has Carmack made any flights with his prototype? I know he had a flying chair but that is about it. Rutan is running not a show but a proffesional test program. He is going step by step and expanding the flight profile a little each time. That is the way you do it and not kill your test pilot.

        I think that it is great that Carmack is trying to win this prize but Rutan is every bit as creative and know a lot more about building flying machines than Carmack. Saying that Carmack should not worry about Rut

  • Looks good (Score:5, Interesting)

    by Skyshadow ( 508 ) on Tuesday March 16, 2004 @02:01PM (#8580821) Homepage
    Ship looks pretty tight, IMO.

    Of course, the project we have to compare it to is John Carmack's Armadillo Aerospace venture (since they have the decency to provide week-by-week status reports, which I consider manditory Monday reading). The folks at Armadillo are still working on getting their engines to light reliably (extra important since they're using five of them) and still haven't had anything like a successful test flight.

    I dunno, man -- If I'm Carmack, I'm thinking it's time to really get at it if you're still serious about winning the X-prize. The SpaceShipOne folks seem to be putting them further and further into the rear-view. Which isn't to say they *can't* catch up; if the Armadillo team can get their engines lighting reliably, they should be about ready to bolt the thing together and start flying.

    Man, this beats the heck out of money pits like the ISS, eh? Nothing like a little old fashioned get-the-prize competition to turn up some interesting stuff. Maybe a $100 billion prize for the first company to land people on Mars and bring them back ought to be next -- get the government to cooperate with permits and NASA to share their tech. I'd bet you'd see people there inside a decade.

    • > Man, this beats the heck out of money pits like the ISS, eh? Nothing like a little old fashioned get-the-prize competition to turn up some interesting stuff. Maybe a $100 billion prize for the first company to land people on Mars and bring them back ought to be next -- get the government to cooperate with permits and NASA to share their tech. I'd bet you'd see people there inside a decade.

      Proposal: The first human being(s) to survive one year on Mars and return safely to earth... gets their choic

      • Giving them mars kind of defeats the purpose, doesn't it?
      • And who would do the 'giving', the present owner?

        Or the UN maybe?

        • > And who would do the 'giving', the present owner?
          >
          > Or the UN maybe?

          As I understand it, the only reason the Moon, or Mars, cannot be "owned" by US citizens is because the US is a signatory to a treaty.

          All the US would have to do is say "We withdraw from this convention, on the grounds that property rights are the means by which all persons - Terran or Martian - exercise their unalienable right to life, liberty, and the pursuit of happiness. Mars belongs to the Martians."

    • Re:Looks good (Score:3, Insightful)

      by Orne ( 144925 )
      I wouldn't get too down. This is the USA after all, and the race is rarely won by the "first", and usually won by the "cost efficient" (or, if you're a cynic, it's won by the "heavily marketed").

      After all, today's commercial airline industry [airlinetechnology.net] isn't flying planes built by Burgess, Curtiss, or Loening [centennialofflight.gov]... It was Boeing who got the contracts for training planes during World War I, and commercial transport planes afterwards...
    • I dunno, man -- If I'm Carmack, I'm thinking it's time to really get at it if you're still serious about winning the X-prize.
      He's never been serious about winning the X-Prize. Carmack is interested in CATS (Cheap Acess to Space), and the X-Prize is mostly a sideshow when it comes to that.

  • heat shielding (Score:5, Interesting)

    by black ninja ( 737113 ) on Tuesday March 16, 2004 @02:01PM (#8580826)
    I'm just a lowly undergrad of physics, but won't they need more than just a heat shield on leading edges? Any aero-eng guys out there? I slow to landing speed as you come out of orbit I think you have to come in at a fairly high angle of attack so that you present a large cross-section to the air, and let the drag slow you down. That is why the space shuttles underbelly is all thermo-shield.

    Also, IMHO the ship looks like some high-school science project with way to much duct-tape with the leading edges done the way they have it.

    • You know more about physics than I do probably so I'll leave that- but I'm sure the appearance in the photo is not what the finished product will look like. I would guess that all the tape over things like the windows is there for protection during installation and probably painting.

      What was more funny to me is that the nose piece looks like a giant shuttlecock.

    • Re:heat shielding (Score:5, Insightful)

      by RichMan ( 8097 ) on Tuesday March 16, 2004 @02:09PM (#8580906)
      This is a sub-orbital flight. A parabolic up-down with "comparativly little" speed WRT the ground. A true orbital flight needs momentum to balance out gravity. This means a lot higher ground speed for an orbital flight.

      As this is not an orbital flight there is no excessive velocity to burn off. Hence, the bathtub mode of recovery from altitude.
    • They're not going all that high. They aren't even achieving escape velocity.

      So the re-entry heating won't be all that great. This is one of the things that makes the x-prize achievable.

      MM
      --

    • Heat shielding is minor compared to orbital craft (Score:5, Informative)

      by Dr. Zowie ( 109983 ) <slashdot@@@deforest...org> on Tuesday March 16, 2004 @02:14PM (#8580951)
      Remember (nobody ever seems to) that getting into space is not nearly has hard as getting into orbit. We're used to descriptions of the amazing technology that is used to protect astronauts and such on re-entry -- but that amazing technology is only needed because of the enormous speeds that orbital vehicles have to attain.

      The kinetic energy required to accelerate a gallon of gasoline to orbital speed is more than the chemical energy contained in the gasoline.

      By contrast, "merely" lifting something up 100km doesn't require much energy at all.

      So, er, no, leading-edge heat shields ought to be just fine. Fiberglass or carbon-fiber composites might even survive a flight or two without any shielding at all.

      • Re:Heat shielding is minor compared to orbital cra (Score:5, Informative)

        by ThosLives ( 686517 ) on Tuesday March 16, 2004 @02:48PM (#8581298) Journal
        I can't resist:

        The energy content of gasoline is about 42e6 J/kg.

        Orbital velocity (at the surface of the earth) is about 8000 m/s. Kinetic energy of 1 kg at 8000 m/s is 32e6 J. (That is, you need about 32 MJ/kg)

        However for those who want the whole story, the parent to this is correct: to get all that energy out of the kg of gasoline, you *also* need about 2.8 kg oxygen. Gasoline-oxygen gets you about 11 MJ/kg, which is about a third of what you need to hit orbital velocity.

        To get to 100 km altitude, you need only 0.96 MJ/kg, which is no problem for gasoline-oxygen.

      • This design also uses the wing itself as a massive air brake by tilting the wing, eliminating (or reducing) the need to assume a nose-high attitude (shuttle orbiters pitch up by 30-40 degrees for most of the re-entry phase of the mission, by comparison.)

    • The Space Shuttle comes in a lot faster and through far more atmosphere (Think angle of attack, not just vertical height). These guys are just barely getting out into "space", and aren't anywhere near the altitude or velocity required to get to even low earth orbit, so they don't need much heat shielding at all.

      Of course LEO isn't a requirement for the X-prize.

      Why yes, I am a rocket scientist.

    • Re:heat shielding (Score:3, Interesting)

      by orac2 ( 88688 )
      Don't forget that Rutan's vehicle is suborbital (as are all the X-Prize contendors). The speeds of suborbital vehicles are much lower than orbital speeds: the shuttle has to dump a lot of energy in a short time when coming back from orbit and needs much more thermal protection as a result. For contrast to the shuttle, consider the X-15, which could just reach beyond the 50 mile boundary that marked whether or not you got to add U.S. astronaut to your resume: it didn't require tiles, or an ablative shield, j

      • Re:heat shielding (Score:3, Interesting)

        by golgotha007 ( 62687 )
        consider the X-15, which could just reach beyond the 50 mile boundary

        so, basically you're saying that i can win 10 million bucks if i can reverse engineer technology developed before 1959? yes, that's 45 or more years ago.

        neato

        • And do it without the massive funding the USAF has. (yes, folks, the X-15 program wasn't a NACA/NASA effort.)
        • The X-15 was relieved of having to rely on its own propulsion (for the most part) to reach that altitude. The aircraft was carried under the wing of a B-52, then dropped off at 45,000 feet after which the four hydrogen peroxide rocket motors would be ignited.

    • Re:heat shielding (Score:3, Informative)

      by PD ( 9577 ) *
      You'd need a lot of heat shielding if you were reentering from orbit, but that's not what this rocket ship is designed to do. It's a suborbital ballistic flight profile, straight up to 60 miles, then freefall back down. Orbital profiles have to go up 200 miles, PLUS they need to have 17,000 MPH of speed to maintain the orbit. The forward momentum of an orbital spacecraft is more energy than the potential energy in 200 miles of altitude.

      Spaceship One will only generate temperatures of about 1000 degrees, an

    • How do you know? (Score:2, Interesting)

      by mnemonic_ ( 164550 )
      How do you know how what sort of cooling mechanism is in place or how effective the heat shield will be? Just looking at pictures? For all you know there could be some elaborate fluid cooling system internally distributed, making blunt edges less necessary. Or that heat shield could be more effective than what your extensive calculations and research indicate.

      My point is is that you shouldn't be so quick to judge. Or maybe you're just shoehorning some semi-related facts in an insightful-sounding post t
  • I think that the work being done by Scaled Composites will prove very useful in the next few years. Where I thank we need to see a much greater effort is in the fuels to drive these kind of vehicles. With advances in physical chemistry we could see an improvement of 2 or 3 orders of magnitude. With those kind of fuels one could put a bottle rocket into orbit!
    • Give yer head a shake, lad. 2 or 3 orders of magnitude means 100 to 1000 times more (unspecified rocket fuel goodness).
      Improvements usually come a few percent at a time.

    • Re:Needed: Improved Fuels (Score:2, Interesting)

      by Anonymous Coward
      Uh, bullshit.

      Cryogenic hydrogen/oxygen (LOX/LH2) is about the best you can get without big handling difficulties. You can go with flourine combos, but that only nets another 3%-4% ISP with truely horrid handling problems.

      There's no "improvement of 2 or 3 orders of magnitude" coming anywhere.

      And LH2 has the problem with needing huge tanks because it's so non-dense. If you consider tank size, you can actually get more into orbit on a smaller/lighter vehicle using LOX/kerosene like the Saturn V. The smaller

    • Re:Needed: Improved Fuels (Score:5, Informative)

      by Rorschach1 ( 174480 ) on Tuesday March 16, 2004 @02:31PM (#8581102) Homepage
      Where do you get that information from? I'm not a physical chemist, but the rocketry books I've read say that chemical fuels aren't going to get much past 450 to 500 seconds Isp. The SSMEs get about 450, I think. Isp (specific impulse) is directly proportional to exhaust temperature, which is always going to be an issue in practical rocket design.

      The 1970's NERVA nuclear rocket program managed to get about twice the Isp of our best chemical rockets with a decent amount of thrust. Ion drives might give you an order of magnitude improvement over chemical rockets, but they don't have the thrust to be used in launch vehicles.

      The only propulsion system I've seen proposed that could realistically produce 2 to 3 orders of magnitude increase in efficiency is the Orion drive. The government doesn't like the idea of building hundreds of small, clean nukes, though. Greenpeace gets a bit riled up about it, too.

      Of course, if I had my way, they'd be welcome to protest right at the launch site.

      • The why (and some of the difficulties) of NERVA (Score:5, Insightful)

        by Dr. Zowie ( 109983 ) <slashdot@@@deforest...org> on Tuesday March 16, 2004 @03:20PM (#8581594)
        Yup, chemical rockets can't get much past about 500 seconds because there just isn't any more energy in chemical bonds. The game in rocketry is to dump as much momentum as possible into as little propellant as possible. The rub: putting momentum into mass requires energy. Momentum scales linearly with your rocket's exhaust speed; but the kinetic energy of the exhaust scales like the square of the exhaust speed! Hence, the more propellant efficient you are, the more energy you need per unit mass. If I recall right, the most energetic-per-unit-mass reaction is atomic hydrogen bonding with atomic fluorine, yielding 0.1 eV/amu of fuel -- that translates to 9.6 megajoules per kg of fuel, or (with perfect conversion) about 4500 meters/second exhaust speed. Divide by 10 m/sec^2 to get Isp, and you find that 450 seconds is the limit for chemical rockets.

        Nuclear reactions yield about a million times more energy per unit mass than do chemical reactions, so it's natural to try to get the energy that way.

        NERVA got OK Isp (about a factor of 2 better than chemical rockets, something like 1000 seconds), but its thrust-to-weight ratio was pretty low, about 4 if I remember right. That's because it included a critical, operating nuclear reactor with an actively controlled chain reaction, and them thar things are heavy.

        Thrust-to-weight is just as important as Isp to a rocket: higher thrust-to-weight means you can tote more fuel, payload, and structure for the same Isp, since you always have to have the mass of the engine itself around. By contrast to the NERVA's thrust-to-weight of about 4, the Space Shuttle main engines have a thrust-to-weight ratio of around 75. Since solid rockets are technically made out of their own fuel, their effective weight is much lower for this calculation (pretty much just the bell nozzle) and you might see numbers in the several-hundreds range.

        Of course, one could always work on making the NERVA more lightweight -- but do you really want to optimize a nuclear reactor for mass, rather than safety? I didn't think so.

        Now, for use in space, thrust-to-weight isn't so important. The rocket doesn't have to support itself against gravity, so low-mass engines that also produce low thrust are perfectly OK.

        Of course, international treaty bans the use of critical nuclear reactors in space, but that alone wouldn't slow down our current administration very much.

        [Nuclear reactors get flown into space all the time, but they always have much less than critical mass, relying on spontaneous decay to keep the chain reaction limping along at a constant rate. NERVA would require controlled reaction rates, hence a critical-mass reactor.]

        • Yeah, NERVA demonstrated at least 900 seconds Isp if I remember right. The thrust-to-weight wasn't 4:1, but 3:4. In other words, it'd never be able to get itself off the ground.

          Orion gets around the exhaust temperature problem by having the reaction external to the rocket. You've got a series of small nukes that create superheated plasma that pushes against a huge steel plate. 'Project Orion: The True Story of the Atomic Spaceship' by George Dyson goes into a lot of detail and presents some of the hist
    • With advances in physical chemistry we could see an improvement of 2 or 3 orders of magnitude. With those kind of fuels one could put a bottle rocket into orbit!
      With those kind of fuels, a suicide bomber could destroy a medium-sized city.
      John Sauter (J_Sauter@Empire.Net)
    • All valid points from today's perspective on what constitutes a safe and stable fuel. However there are clearly many more unstable fuel possibilites. Perhaps a mechanism can be designed to use the stable materials to produce unstable materials in a pre-reaction chamber before introducing the unstable product to the reaction chamber. Look at the progress that's been made in chemical lasers. Just a few decades ago they were a joke, now they represent a credible advance in high power anti-missle technology

  • Armadillo Dreamin' (Score:5, Interesting)

    by Ephboy ( 761440 ) on Tuesday March 16, 2004 @02:08PM (#8580895)
    Apparently, Scaled Composites is one of two teams to have applied for a permit from the FAA [space.com] to launch a spaceflight. The other is Armadillo Aerospace [armadilloaerospace.com], run by John Carmack of Doom fame. It's interesting to compare and contrast the two companies. Rutan has a sleek ship with lots of cool round windows that launches from a funky big plane, and they have some good solid live testing. The Armadillo team's site really shows you the nitty-gritty of building something that flies in your spare time, with pictures of them welding engines together, making a crew capsule out of whatever they could find, and building a landing gear with some thick cable springs. I'm guessing that Rutan will win, but I'll hold out hope that the garage engineer can pull off at least some type of flight to give courage to that old entrepreneurial spirit....

    • Re:Armadillo Dreamin' (Score:5, Insightful)

      by Skyshadow ( 508 ) on Tuesday March 16, 2004 @02:17PM (#8580991) Homepage
      I'm not sure it's fair to characterize Rutan and Carmack this way.

      Neither of these guys are professional rocket builders. They're both private individuals spending their (ample) money to compete for the X-prize. Rutan has previous experience building aircraft and has worked more at putting together a team and securing infrastructure to help with the build, but it's not as if Rutan is leading a billion-dollar team of button-down 1950's engineers at Boeing or something while Carmack is competing out of his back yard shed.

      Just because Carmack posts his day-to-day struggles on the web for us all to enjoy (and I *do* enjoy it, BTW) doesn't imply that the SpaceShipOne team isn't encountering the exact same sorts of technical hurdles, supply problems, permit bullshit and etc. In other words, whichever wins will be a victory for the little guy because they're *both* the little guy.

      • Re:Armadillo Dreamin' (Score:5, Informative)

        by RedWizzard ( 192002 ) on Tuesday March 16, 2004 @02:52PM (#8581339)
        They're both private individuals spending their (ample) money to compete for the X-prize.
        Please note that neither of these teams got into this for the X-prize. Carmack wanted to put someone in space for the hell of it, and Rutan is trying to develop a commercial space tourism platform. For Carmack the advent of the X-prize meant aiming for an X-prize sized vehicle earlier than otherwise. In Rutan's case the X-prize will nowhere near cover the cost of development (which I've heard is around $30M, IIRC), but will certainly reduce it.

      • Re:Armadillo Dreamin' (Score:4, Funny)

        by LS ( 57954 ) on Tuesday March 16, 2004 @03:01PM (#8581428) Homepage
        Hmm, I don't know if I agree with your characterization either. So Rutan is not a rocket builder, but he has a massive aviation engineering background and physical infrastructure in place. The difference between the Carmack and Rutan teams is likely significant - to balance it out, I would bet that Rutan would have a hell of a time building a top-notch first-person shooter...

        LS

  • I'm waiting... (Score:5, Funny)

    by Seoulstriker ( 748895 ) on Tuesday March 16, 2004 @02:09PM (#8580908)
    I'm waiting for Carmack to respond to the space race. I'm also waiting for a release date for DooM3! :)

  • A good thing too (Score:5, Interesting)

    by Anonymous Coward on Tuesday March 16, 2004 @02:10PM (#8580913)
    They better not have any more delays like that last one, if they want to win the X-Prize. The $10 million dollar prize expires at the end of this year, and a lot of other groups are competing for it.

    I think we'll see some exciting new developments in space technology over the next few years. I'm confident someone will win the X-Prize [xprize.com],(which is more a PR bonus for starting a space tourism company than anything else) the Bush Admin wants to send folks to the moon or Mars (probably using nuclear propulsion), and it's all but a foregone conclusion that someone [liftport.com] will try to build a Space Elevator soon.

    • Re:A good thing too (Score:4, Funny)

      by LS ( 57954 ) on Tuesday March 16, 2004 @02:53PM (#8581350) Homepage
      Dude, you're not a prophet, but you are a good Karma whore. What does the Bush administration and Mars have to do with this? How could you know what propulsion system is going to be used without NASA even working on it yet? And this Space Elevator company is a bunch of nerds building Lego Mindstorm models of their fantasy elevator!!!

  • Despite what it looks like... (Score:4, Interesting)

    by CBob ( 722532 ) <crzybob_in_nj&yahoo,com> on Tuesday March 16, 2004 @02:20PM (#8581022)
    Rutan and Scaled are prob the Ultimate Gargage Engineers. He's done stuff that "experts" called impossible for years.

    The "early" kit planes he designed are still works of "art".

    (bad news, the site is /.ed)
  • It is soooooo Buck Rogers-esque!! Not the late 70's/early 80's TV show Buck Rogers, I mean the 1930's - 1940's Buck Rogers.
  • Shotgun!!!!!!

  • TPS report (Score:2, Funny)

    by Apogaion ( 107849 )
    I wouldn't trust any Thermal Protection System until all the employees have submitted their TPS reports in triplicate.

  • no pilot will fly a pink spaceship... (Score:3, Insightful)

    by black_widow ( 41044 ) on Tuesday March 16, 2004 @05:14PM (#8583005) Homepage
    If you don't believe me, look at the x-15 x-15 in full ablative coatings [nasa.gov]. The pilots wouldn't fly it [nasa.gov] unless they put a painted on top of it...

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