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Personal exteriorless 'copter

  1. Sep 12, 2005 #1
    This idea came to me in a most peculiar dream, and I was wondering if it would be possible:

    Basically, it would be a backpack that you strap on with arms that come down (like a car seat) with controls at the ends. You start up the little engine in the backpack and mini helicopter blades extend up and outwards, just powerful enough to lift yourself and the engine. The retractable blades would mean you wouldn't have to tie up the contraption like a bike when entering buildings.

    Is there an engine that could be powerful enough to do this (yet light enough to carry around?) If so, it could have tremendous implications for personal transit.
     
  2. jcsd
  3. Sep 12, 2005 #2
    There are a few problems with this idea.

    1.) Counter-torque - in order to keep the passenger from spinning opposite the rotor, the machine would need two counter-rotating sets of rotorblades. The gearing to do this would make the vehicle bulkier and heavier (thus being less practical and requiring a larger engine)

    2.) Weight - without doing a product survey, I'm going to say that there are engines with a high enough power-to-weight ratio to accomplish this, however I don't know if they'd be "light" enough to carry around all day (as you seem to indicate in your idea).

    3.) Practicality - in reality, would you want any yay-hoo who could aford it flying overhead? Personally, I wouldn't. There are some people I don't even think should have DRIVER's licenses.

    A good idea, but one that has already been thought of and deemed impractical. Nonetheless, keep up the brainstorming.

    Cheers...
     
  4. Sep 12, 2005 #3

    LURCH

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    Thought you might find this to be of some interest.
     
  5. Sep 12, 2005 #4

    FredGarvin

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    To an extent, it has been attempted, just not in the small scale you are referring.

    http://www.richguy.com/luxury/lifestyle/magazine.php?car=AIR&id=SoloTrek+XFV&aid=55&page=1

    The company's web site is defunct as much as I can tell, so I have a feeling that they have lost funding for it.

    The big issues I see are the following:

    1) Engines: Reciprocating engines are not so good when it comes to power to weight ratio. They are heavy for the amount of power they put out. That is why most helicopters today use turboshaft turbines.

    2) Fuel. Fuel is heavy. You'd probably loose any lifting advantages by going small when you add the weight of the fuel.

    3) Heat/safety. Engines are heat producers. I don't think you'd want something that hot on your back with just a backpack in between you.

    4) Complexity. Rotary wing controls are very intricate and complicated. I don't see how you'd be able to make the connecting components small enough and compact to be able to make it so a person could carry it. Plus, like Lunchbox mentioned, you would have to have tandem rotors to alleviate counter torque issues.
     
    Last edited: Sep 12, 2005
  6. Sep 12, 2005 #5
    sounds like a great way to get a marine haircut from the neck up.
    No....... can't say I would like a blade whoop whooping just above the old grey matter.
     
  7. Sep 12, 2005 #6

    DaveC426913

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    Last edited: Sep 12, 2005
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