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Private Rocketplane Test A Success

HobbySpacer writes: "XCOR announced the success of the first phase of flight tests for the EZ-Rocket. In the most recent flight, Dick Rutan fired both of its rocket engines to take off and reach a speed of 160knots and an altitude of 6200 feet. The vehicle is a Long-EZ kit plane modified to hold twin 400 lb thrust rocket engines fueled by isopropyl alcohol and liquid oxygen. The project is not aimed at a homebuilt EZ-Rocket but will demonstrate safe and reliable rocket propulsion. The primary goal is development of reusable launch technology that leads next to a high altitude sub-orbital rocket vehicle for space tourism, rocket racing (e.g. vertical drag racing at air shows) and the X-Prize competition."

23 of 283 comments (clear)

  1. Pointless by kin_korn_karn · · Score: 3, Insightful

    Rockets are the most inefficient method of propulsion that's still in use, a better goal would be figuring out an entirely new propulsion system that could apply to everything. Speaking of which, what's the latest on Ginger?

    And furthermore, who cares about "vertical drag racing"? Drag racing cars is fun because it's something everyone can relate to. Very, very few people can relate to racing rockets.

    1. Re:Pointless by Rogerborg · · Score: 5, Informative
      • Rockets are the most inefficient method of propulsion that's still in use, a better goal would be figuring out an entirely new propulsion system that could apply to everything

      Got any ideas? Once you're at the edge of the atmosphere, you're pretty much limited to using a self contained reaction motor.

      Ground laser launching relies on superheating air, plus it's only been used to shove vehicles directly up, so it's basically a really cool but expensive way to replace July 4 bottle rockets. A more viable alternative is turning beamed EM into electricity then powering magnetohydrodynamic motors that superheat air, but you still have that pesky problem that you are relying on an atmosphere to get your speed.

      You could accelerate the vehicle in a rail gun or rocket sled until it reaches orbital velocity while it's still on the ground. Ballpark figure, at a (barely) survivable 20g, you'd need a 150km track to reach the 7.73km/s orbital velocity of a typical shuttle mission, ignoring air resistance. Except you can't ignore air resistance, because at 7.73km/sec at 1 atmosphere, you'd burn the vehicle to a toasty crisp.

      Even if you postulated antigrav, you still need to generate lateral acceleration to achieve orbital velocity, which again requires a self contained rocket, or an atmosphere.

      A beanstalk (space elevator)? Heck, maybe we've already got the technology to do it, but we're not going to, not for a long, long time.

      So, really, if you've got any ideas about what to use as an alternative to rocketry today, let's hear them. I'm fresh out.

      --
      If you were blocking sigs, you wouldn't have to read this.
    2. Re:Pointless by Catbeller · · Score: 3, Informative

      The "rocket sled" (actually a linear induction motor used as a railgun of sorts, also called a mass driver by Gerry O'Neill and company, and first dubbed a "catapult" by Heinlein and something totally else by Clarke) doesn't have to accelerate the ship to orbital speed. That's ludicrous.

      It merely has to replace the first stage, and that only requires a few miles of track, an upwardly sloping mountainside, and a few G's of acceleration. One the ship leaves the mouth of the catapult, it's moving fast enough for a very small fuel tank to kick it all the way to orbit -- not to mention the fact that at mountain height, it's past a goodly chuck of the atmosphere pretty quickly.

      It's surprising how little ship you need to achieve orbit once you get rid of the first few miles and get some speed buildup. The ship is SMALL.

      A catpult would prolly use maglev, be pretty cheap once the thing is built, and only require electricity to operate instead of rocket fuel. And it is reusable to a ridiculous degree.

  2. Some People Shouldn't Have Kids by ekrout · · Score: 3, Funny
    In the most recent flight, Dick Rutan fired both of its rocket engines to take off and reach a speed of 160knots and an altitude of 6200 feet.

    If your last name was Rutan (read "Rootin'"), you should not name your kid Richard (or encourage the nickname Dick!). This is common sense.

    Thankfully, Bart & Lisa's prank calls to Moe on The Simpsons should discourage future "Hugh Jass"s, "Ivana Tinkles"s, and "I.P. Freely"s.

    --

    If you celebrate Xmas, befriend me (538
    1. Re:Some People Shouldn't Have Kids by unitron · · Score: 3, Funny
      He pronounces it Roo-tan.

      What about Nascar's unfortunately named Dick Trickle? Maybe his parents were operating on the "Boy Named Sue" theory.

      --

      I see even classic Slashdot is now pretty much unusable on dial up anymore.

  3. Rocket racing may be the "killer app". by Nindalf · · Score: 4, Insightful

    Think of how much money goes into car racing. Rocket racing would be an incredible spectacle.

    This could easily lead to full funding for the transitional stage of private rocketry before the obvious profit potentials of orbital flight.

  4. Unit conversions by metricman · · Score: 3, Informative

    160knots = 296 km/h
    6200 feet = 1890m
    400 lb = 1779N

    A cool feature for slashcode would be automatic unit conversions.

    1. Re:Unit conversions by marm · · Score: 3, Informative

      The whole idea of metric is that we should put all of our eggs in the one basket, so that people with certian brain defects would not be able to understand it. I found little logical in it to understand what people see so wonderful in it, and I have studied it for thirty years now.

      Umm, no. The beauty of metric, or rather the more modern form of metric called SI (Systeme Internationale) is that:

      a) multiples of a unit are always in base 10, so it is obvious that 27km = 27000m, and it is just as simple to write that in scientific notation (i.e. 27km = 2.7x10^4m) - you try telling me what 27 miles is in feet without reaching for a calculator

      and b) there is a small set of measured base units (there are 7 - metres, kilograms, seconds, amperes, kelvins, moles and candelas) and every other unit used throughout science and engineering is directly derived from these base units without any fudging

      Quite apart from the obvious benefits for calculation, it also makes things much easier to understand in your head - you only need to know the size of the 7 base units to be able to have some idea of exactly what each derived unit means. Also, if you are sticking to SI notation to the letter, it is plain from the name of the derived unit exactly how it is derived from the base units.

      Really, it is perfectly logical, and a heck of a lot simpler to learn than the old Imperial or Imperial-derived systems, where there were about 3 times as many different base units. Science has adopted SI worldwide, partly for its ease and simplicity, and yes, partly because scientists want to be able to understand each other. In most countries, engineers have also adopted the system for similar reasons, and even the general populace understands most of it thanks to everyday things being measured in SI units or multiples of - masses in grams or kilograms, volume in litres, distances in metres or kilometres.

      Anyway, in SI Units...

      160 knots = 82 ms^-1 (metres per second)
      6200 ft = 1900 m (yes, this one was right :)
      400 lbf = 1800mkgs^-2 (meters per kilogram per second, aka newtons)

      All conversions rounded to 2 significant figures... now, who's going to be the first to complain about the use of significant figures? ;)

  5. Re:Rocket Racing? by Alien54 · · Score: 3, Interesting
    Is it just me or does anyone else think that pushing the limits of rocket design technology at public airshows might not be in the best interests of public safty?

    The best thing would be a one way run away from a crowd, say out into a desert.

    Just make sure the chutes do not fail.

    Sound like something that could be cool out in a place like Death Valley.

    --
    "It is a greater offense to steal men's labor, than their clothes"
  6. Re:Wait a sec by Gorobei · · Score: 4, Insightful
    H2O2 is a walk in the park compared to liquid O2. Both are quite nasty, but people usually survive a dousing in 95% hydrogen peroxide: yes, you are porcelain white for a few weeks, but you live. That assumes you have a decent shower on-site (think water-tower, not hose-pipe.) O2 accidents of similar magnitude kill you: cryogenic freezing, plus O2 mixes with organics to form pressure-sensitive explosive slush.


    LOX eats through bad rocket elements (e.g. below spec piping and valves) much faster than H2O2, and the low temp makes valve sticking and thermal mismatch failures much more likely.


    To get equivalent safety, working with LOX will cost 10 times as much.

  7. ah Crap! by OO7david · · Score: 3, Funny

    Now, not only do I have crapily modified cars running down main street fridays and saturdays, but now I also have to deal with these jerks interruptin my flight!? I don't want to see a rocket with a 4' muffler, it's not cool. I don't care if your rocket has a Vtec engine. I want to fly safely from point A to point B, much as I would like to drive from point A to point B without having your terrestial counterpats fly past me at 100+ mph.

    Honestly, kids these days.

  8. A demonstration of O2 danger by drodver · · Score: 4, Funny
  9. Re:umm, what about balloons? by Gorobei · · Score: 5, Informative

    The main reason is the FAA. If you want to be a high alt attempt, you need to file a lot of paperwork concerning your flight plan and risks to populated areas/foreign airspace. In theory, you could get approval for an orbital shot from two places in the USA (Black Rock and Alaska,) if you have a self-destruct device on board. Note that a self-destruct doesn't make the rocket vanish, it just puts the debris in a safe zone. Now, if you want to float to 120,000 feet before launch, your debris zone is about the size of the Pacific Ocean. You don't get approval, end of story.

  10. life during wartime by motherhead · · Score: 3, Interesting

    The primary goal is development of reusable launch technology that leads next to a high altitude sub-orbital rocket vehicle

    Could a missile fired from sub orbit on an (relatively) inexpensive platform such as this one, actually knock out a satellite?

    Yes I realize that the missile would have to be expensive enough with it's payload and whatever guidance it would need to find it's target.

    But if these things can be made as cheaply as they say, I wonder if small governments (okay i am sicking of typing the "T" word) could use this kind of technology to cause a lot of mayhem.

  11. Re:It's all about velocity, not altitude. by Chakat · · Score: 3, Interesting

    Actually, a balloon first stage is incorporated into a number of fairly credible amateur rocket designs. By using a balloon to bypass the heaviest 15-20 miles of the atmosphere, you're cutting down not only on drag, but distance. This means you have to carry considerably less fuel, leading to a smaller, cheaper, and possibly more reliable design. It probably won't be used for getting large multi-ton objects into space, but for a small one-two man capsule, or a small satelite, a balloon launch makes a good deal of sense.

    --

    If god had intended you to be naked, you would have been born that way.

  12. Rotary Rocket gone by Animats · · Score: 3, Informative
    Rotary Rocket is gone. Sad. They had a launch vehicle that was supposed to go suborbital, and probably would have worked. The helicopter-type landing system passed flight test. Another Rutan airframe design, by the way.

    The big problem was that the new engine concept didn't work out, and using off the shelf engines doomed the thing to suborbital flight, for which there is no commercial market.

  13. Re:Rocket Racing! by Kris_J · · Score: 3, Funny

    And next season on Junkyard Wars two teams will have 10 hours to build their own Rocket Racers! (While the American host wanders around mispronouncing "pumpkin".)

  14. Re:umm, what about balloons? by Chris+Y+Taylor · · Score: 3, Informative

    I think you are refering to a "rockoon".

    http://www.friends-partners.org/mwade/lvs/rockoo n. htm

    They were invented by Dr. Van Allen and some of his associates. They were only for sounding rockets, which explore the upper atmosphere but don't go into orbit. If you want to go into orbit, you still need a lot of horizontal velocity so the rockoon is not as handy for that.

  15. Re:Is sub-orbital flight worth the risk ? by Chris+Y+Taylor · · Score: 3, Insightful

    It doesn't matter whether you think the risks are worth it.

    It matters if the potential customers think the risk is worth it.

  16. Extreme (rocket) Programming by warpeightbot · · Score: 5, Insightful
    It looks like Buzz Aldrin's got some competition now.... Buzz had been going at it with the idea of adapting existing missile tech in clusters to form a cheap booster for commercial space.... but it looks to me like he was using the cathedral method of design. Big and slow.

    On the other hand, it looks like the Rutan brothers are using something like Extreme Programming to build rockets... build up little by little, test daily, twice, three times a day, use existing airframes as testbeds (Dick Rutan could fly a LongEZ in his sleep, and probably has by now :) .... and you know damn good and well that when they get a reliable product they're gonna release it as a kit.

    (drum roll please)

    Open Source Aviation!

    No, I'm serious... when you buy a kitplane, you get the source (plans, etc.), and you are perfectly free to hack'em, and post your results and sell the resulting product. (Kindof a BSDish license... 1/2 :) The original 2-seat pusher LongEZ became the 4-seat Velocity, the taildragger Quickie, and inspired the commercial LearStar and Beechcraft StarShip designs.

    Yeah, aircraft design is kinda like doing something the size of Mozilla.. but once you've got something working (and the VariEze/LongEZ designs have been around for... well, the old VariViggen (the granddaddy of all homebuilt canards) the Museum of Flight was registered in 1972, so.... and once you've got something it's dead easy to do incremental improvement and even rapid prototyping.

    They've been doing this on a shoestring budget (I know how the Rutan brothers work, that's how they built Voyager) for about two years now, and they've got a bird in the air alreddie... where the Zoche folks have been at this aerodiesel thing for six years now, and still don't have anything flying... which is a reflection of the design philosophy; Zoche is going for an FAR-23 certified engine up front, where XCOR is happy to get something off the ground in a safe manner... in much the same way as Netscape would write this huge thing ground-up and only release it when it was all done as opposed to Mozilla pumping out milestone after milestone as things gradually started working...

    In short, real-world, non-code-geek example of why bazaar-style development works.

  17. Carmack's the Competition by deathcow · · Score: 3, Interesting

    I find it unbelievably strange that John Carmack (of Doom,Quake fame) is also building a rocket capable of transporting humans. He's made a ton of progress. His company: Armadillo Aerospace

  18. Rocket Science is Already Open Source by Chris+Y+Taylor · · Score: 5, Insightful

    I hate to break this to the programming community, but you did not invent the philosophy of "open source" or the "bazaar vs. the cathedral."

    Science has had an "open source" component for pretty much as long as there has been modern science. Everybody works on some little bit of the problem (figuring out how the universe works), and when they have something they think is reasonable they publish it for everyone else to critique. Such publications may not technically be free, because you have to subscribe to the journals, but in reality if you go to any science library you can get free access to them. Really, the philosophy of finding mistakes by releasing code as "open source" so that a lot of other people can look at it and tinker with it is the same old philosophy behind peer-review and publication of scientific papers. The "open source aircraft design movement" exists; it is called "Journal of Aircraft" and is delivered to my home every couple of months.

    This may get me modded down, but I think that "open source" is just Computer Scientists figuring out something that the other branches of science have already known for a very long time. Getting new developments into the public domain and letting other researchers bang around on them will yield even newer and better developments. One team of people locked away in isolation is not nearly as likely to develop a workable product (which for science would pretty much be a model of everything in the universe.)

    That said, I don't think the idea of developing aircraft the same way that you develop programs is a good idea, because they are NOT the same sort of things. I'm sure you all know the joke about if Airplane development went like Computer development then we'd already have hypersonic transport aircraft with world spanning range that the average person could afford to own and operate... and they would explode once every week or two killing everyone on board. Aircraft Theory and Aircraft Conceptual Design and Aerodynamic Behavior and other such things are generally done as public science and/or published in journals and presented at conferences (i.e. "open source"). When it gets time to actually design the aircraft, this is done with a relatively small, closed team of people. There is a good reason for this. Airplane and rocket crashes kill people. Pick up a copy of The Right Stuff and read the first chapter. Such things ARE tested regularly. They are tested methodically and often. In wind tunnels and CFD code and on the ground and finally in the air. They are tested with methods and in progressions that were proven to work with VERY costly (in dollars and lives) prior experience. You could call it "extreme programming" for aircraft. Aircraft design is also complex. Simply moving the battery from the front to the back of a plane this size can invalidate all previous flight test data, so it is with good reason that the development is done by people who know the whole picture intimately (a difficult thing for a hobbyist to do). And, many aircraft design groups don't want their detail designs and their "tricks of the trade" to be open source because they are proprietary or classified. Yes, other sciences have "Closed Source" projects, too; but unlike in computer science, they tend to usually be offshoots and niche developments with the bulk of science being "open source" (to use CS lingo). Even big, private company laboratories in other scientific fields publish a lot of "open source" scientific material. Not only do they realize the value of having it reviewed and verified by other scientists "for free," but they also understand the importance of such publication in maintaining their organization's prestige in their industry and in recruiting the best new talent.

    Aerospace has had "open source" for almost 100 years now. Physics has had it since the days of Newton and Galileo. Computer scientists, welcome to the club. Just don't think the rest of us haven't known about this for a long time... and stop tacking the phrase "open source" on everything. Try terms like "peer review" and "in the public domain" on for size; maybe you'll sound less socialist and the public will take it more seriously.

  19. Re:Rocket Racing! by John+Carmack · · Score: 3, Informative

    The rockets we are currently firing use hydrogen peroxide, which produces nothing but water and oxygen in the exhaust. Not even the most rabid greenie could argue with that.

    Hydrogen / oxygen rockets also produce water and excess hydrogen. Alcohol / ocygen rockets leave a few other things similar to auto exhaust, but not really worse.

    Solid rockets leave some bad stuff, and some propellants are truly nasty, like nitrogen tetroxide and hydrazine, but those are also much more expensive, so wouldn't be used in a cost effective program.

    John Carmack