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Aerospace Question about lifting up 90 Kilogram weight

  1. Sep 13, 2012 #1
    I am trying to build a helicopter. please help me.
    I want to know how much RPM and size of blade needed to lift 90KG of weight.

    I am planning not to use tail rotators, but I have a solution for this.
  2. jcsd
  3. Sep 13, 2012 #2
    Is this a troll or are you serious?
  4. Sep 13, 2012 #3
    Yes man!!
    did I asked anything wrong?? is it not possible.

    Actually I am have not much knowledge in Physics, cause i am IT Engineer.
    Due to my interest in science, I made a small helicopter. And it works.
    Now i want to make a small helicopter which will lift a man.

    Any suggestion will help, I will show you project design if you want.
  5. Sep 13, 2012 #4
    The first helicopter was a chair with a rotary blade attached to the top of it. It did not go well. There are a few things they did not consider. The first is that this setup will tip over due to the change in pressure distribution the blade creates, and the chair will also rotate, although not as fast as the blade. This is considering your design is structually sound and you have enough power to get it off the ground.

    The solutions were a blade with hinges that compensate for the uneven pressure distribution and a tail rotor to counteract the base rotation.

    To answer your question though, it's probably not a good idea.
  6. Sep 15, 2012 #5
    Thanks Vadar2012

    I am planning to use coaxial propellers.
    Can you suggest me any Electric MOTOR and Lithium battery to use in my project
  7. Sep 15, 2012 #6


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    Science Advisor

    Helicopters of the type exist. See this article. I don't think any existing lithium battery stores enough energy to lift you for more than a short time. You will probably need a fuel-powered engine.
  8. Sep 15, 2012 #7


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    Science Advisor

    Check out this link. I think this is what you are aiming at.
  9. Sep 15, 2012 #8
    phyzguy thanks,

    I will inform you more about the project after I start work on it.
    Can you tell me any site where I can buy robotics and electric motors??
  10. Sep 15, 2012 #9
    It is very hard and challenging task to make a coaxial rotor Head.

    for rotating helicopter body In coaxial rotor I need to slow down a propeller,
    is it right????
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