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Rocket Men

Posted by ryuzaki0 on from the excellent-reason-to-go-into-traction dept.

theodp writes "Slate reports on the guys who really, really want to fly, who got together the other week at the Niagara Aerospace Museum for the First International Rocketbelt Convention. To date, only 11 men in history have free-flown a rocketbelt (aka JetPack). More men have walked on the moon. Why? 'It's not a matter of if you get hurt, it's when,' says Eric Scott, an ex-stuntman who's in the exclusive club."

15 of 150 comments (clear)

  1. Re:And this is different from by Itninja · · Score: 3, Insightful

    I guess the big difference is that if you bite it boarding, you might get seriously hurt. With an outside chance of death. Whereas, if your 150ft in the air, travelling at 25mph, and your jetpack decides to crap out.... there would only be an outside chance of NOT becoming a mangled corpse.

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  2. Re:And this is different from by Thisfox · · Score: 3, Funny

    Well, for a start, you are much less likely to run out of fuel 18 metres up in the air while on a skateboard...

  3. Gyroscopic stabilizers by Anonymous Coward · · Score: 5, Interesting

    These people need computer-controlled gyroscopic stabilizers. A fly-by-wire system could dramatically improve the safety of rocketbelts. No doubt that would make them much more popular.

    1. Re:Gyroscopic stabilizers by evanbd · · Score: 5, Informative
      And while we're at it, that's a *hell* of a lot easier said than done. You can't do it on cheap gyros (read: you're probably spending $5-10k per axis), and they're not particularly light weight (a couple pounds each may not seem like much, but it eats into your fuel budget quite quickly). And you need a *good* control program, which isn't easy to write. Getting it mostly right wouldn't be too hard, but would you trust your safety to "mostly right"? To date, only one VTVL rocket vehicle has demonstrated fully autonomous takeoff, hover, and landing (John Carmack's vehicle over at Armadillo Aerospace). It ain't easy.

      Also, don't forget you have to build the rocket motors and feed system and such. Most belts so far are peroxide monopropellants -- a good choice IMHO, but peroxide is hard to get and takes a lot of care to handle safely. And building any size rocket motor and ensuring it's safe enough to stand next to is a bit of work.

      What I'm saying is, if you're a single amateur, or a small group, then building just the rockets is a big project unto itself. It shouldn't surprise you that no one has the time, money, and skills to do that, *plus* build and test the IMU, *plus* write fly-by-wire control software for it. If a modest sized startup company decided to pursue the matter, with a bit of financial backing, I would expect they could get it all built without too much hassle (provided they had the appropriate expertise in all areas, obviously). Oh, and don't forget that your software has to handle a non-fixed CG if the person moves about much at all.

    2. Re:Gyroscopic stabilizers by jcr · · Score: 5, Interesting

      You can't do it on cheap gyros (read: you're probably spending $5-10k per axis),

      Why not? There are gyros that model helicopters use that are cheaper than $100, and an RC chopper is a whole lot twitchier than something with the mass of a human being in it. If your flight only lasts for a couple of minutes, then you hardly need high-precision gyros that won't drift more than a degree per hour.

      -jcr

      --
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    3. Re:Gyroscopic stabilizers by evanbd · · Score: 3, Insightful
      Hmm. I don't know how good those gyros are; I was of the impression that there wasn't really a whole lot between the cheap sensor grade stuff and the good navigation grade fiber optic ones. Also, AIUI the differences aren't just in drift rate, but also in things like vibration sensitivity and cross-axis coupling.

      I suppose you could use the inexpensive ones, as long as your goal was to change the pilot requirement from "top of the line test pilot" to "very good helicopter pilot," and not an attempt to make it flyable by anyone with a bit of simulator practice.

      You might do an ok job if the gyros just tried to hold the spin *rate* to zero, and let the pilot handle leveling the vehicle; one fewer integral makes for much slower error growth.

  4. Re:And this is different from by Excen · · Score: 4, Funny

    Well, for a start, you are much less likely to run out of fuel 18 metres up in the air while on a skateboard...

    What? You mean those Mountain Dew commercials aren't accurate representations of the sport of skateboarding?

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  5. How many people have flown a jetpack? by Brad1138 · · Score: 5, Funny

    To date, only 11 men in history have free-flown a rocketbelt (aka JetPack)

    Make that 12, your forgetting Duke Nukem.

    --
    If you could reason with religious people, there would be no religious people
  6. Re:rocket "belt" by garcia · · Score: 3, Funny

    Why is it called a rocket "Belt", when it's typically something the size of a surfboard with a pair of propane tanks that you strap on your back?
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  7. Sounds like a job for real-time computers by dpbsmith · · Score: 3, Interesting

    It's understandable that in 1961 the pilot needed to fly the rocket belt with only his own reflexes and semicircular canals to guide him.

    But even in the late 1960s my aero-and-astro student colleagues told me that even the Boeing 727 was too unstable to be controlled by a human pilot using reflexes alone: it relied on "yaw dampers," servo mechanisms that amounted to electronic analog computers, to tame the raw behavior of the plane.

    The Boeing 777 is a completely "fly-by-wire" design.

    It seems to me that it ought to be possible to design microprocessor-controlled rocket belts that would be much easier and safer to fly than those of the 1960s. (Including, of course, electronic active noise cancellation in the helmet to provide at least some reduction of the "deafening noise 3 feet three feet from his ear."

    Trying to fly the rocket belts described in the strikes me as rather like trying to fly a full-size, exact model of Langley's Aerodrome. It may be possible--for someone with the reflexes of a Santos-Dumont and the nerves of an Evel Knievel--but it's still just a stunt. The Wright Brothers achievement was ''not'' building an aeroplane that could get off the ground; it was building an aeroplane that they ''and others'' could get (relatively!) ''safely'' off the ground.

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  8. What about women? by Dan+East · · Score: 3, Informative

    To date, only 11 men in history have free-flown a rocketbelt (aka JetPack).

    According to the Wikipedia article, at least one woman (Isabel Lozano) has flown one as well (happened almost a month ago).

    As to why haven't more people flown the device, take a look at Isabel's pictures, and you'll see that had to make a custom cast of her body for the mounting hardware the device uses. Also, for some reason many people may not feel very comfortable with jets of gas at 740 C venting at supersonic velocities mere inches from their body.

    Dan East

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  9. On the Fringe by tb3 · · Score: 5, Interesting

    The (strange/interesting/sad) part of this story is how far out the people involved are. I noticed there was no mention, either in the Slate article or the actual convention website, of these guys who claim to have the only functional rocket belt in existence. Then there's Juan Manuel Lozano, the Mexican inventor who claims to developed a break-through method for creating the 90%-pure hydrogen peroxide fuel needed for the rocket belt.

    And then there's the whole RB2000 saga, which involved fraud, murder, and the disappearance of the only prototype. The full story can be found on the rocketbelt.nl site. Rocketbelt developers are out there on the edges with the ufologists, perpetual motion researchers, and free energy salesman, with the exception that rocketbelts can actually work!

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  10. The Alternative? by webword · · Score: 3, Interesting

    Very light jets!

    2006: The year of the very light jet

    Very Light Jet Magazine

    The Light Jet Age

    OK, so they are a $1-2 million. That's a lot of money. From what I've read, however, these jet packs aren't that cheap either. (They're not mass produced so the price hasn't dropped at all.) If you bought part of a jet as a time share, with say 20-50 other people, the price drops significantly. It is a viable option for some people.

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  11. Re:rocket "belt" by Hangin10 · · Score: 3, Insightful

    This part of it I don't understand. I can understand being strapped to it, but why should the human have to support it? Why not have "_|"-shaped (excuse the ASCII-art excursion) bars under the arms and up over the chest/shoulder area with the human ON the device (like a flying Segway, just not quite so white and nerdy). This probably changes the whole concept, but I'd rather get into what I described rather than strap a rocket to my back. Strapping a rocket to one's back seems rather ill-advised in a rather distinctly "Acme" fashion...

  12. Undocumented by Tablizer · · Score: 3, Funny

    To date, only 11 men in history have free-flown a rocket-pack

    I take it this excludes burrito dinner + sparks accidents?

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