Biplane Rig, is that all you have?

Discussion in 'Multihulls' started by Moggy, Jul 15, 2014.

  1. Moggy
    Joined: Feb 2011
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    Moggy Senior Member



    :confused:


    :D

    More is better! Right?
     
  2. sharpii2
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    sharpii2 Senior Member

    Nope. Four sails that close to one another is not producing four times as much lift. Not even close.

    Biplanes are said to need one fifth less span for wings of the same chord length (distance from leading edge to trailing edge) on a monoplane.

    So there is an actual improvement in lift, with two wings rather than one, but the added lift is no where near proportionate to the added wing area.

    With stacked wings, the lift goes up, but the efficiency goes down.

    The biplane form was used in a time when airframes had to be very light because engines were quite heavy for the amount of power they produced. The biplane form allows one to brace the top wing against the lower wing with a system of struts and and stay wires, to form a truss like system that is very strong for its weight.

    More powerful engines (for their weight) brought about the now familiar monoplane.
     
  3. upchurchmr
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    upchurchmr Senior Member

    I don't think I would have gotten a video on a windless day.

    Unless that is all it can take.
     
  4. Moggy
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    Moggy Senior Member

    errrrr.... um... sarcasm folks, sarcasm.


    Windless, yeah, I think I'd be a little pensive about sailing it in a blow! Looks way too complex for my taste.
     
  5. warwick
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    warwick Senior Member

    does any one know much about Clifton flasher it seams a similar concept to me.
     
  6. Moggy
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    Moggy Senior Member

    I like the idea of more area lower down but I have not seen what I would call a graceful solution, even the Radical Bay 8000's look a little off to me.
     

  7. upchurchmr
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    upchurchmr Senior Member

    Clifton Flasher was interesting as is this boat, but I was never able to find a real commentary for how it worked. With planning hulls it probably jumped up and ran well on a close reach, but died out on a far reach because the sails interfered with each other. Probably did not point real well either.

    Anyone have an old article on the flasher?

    I would like to borrow a pair of the masts for a day sailing trimaran with the masts set as far from each other as possible fore and aft. It would be great fun going back an forth across a lake.
     
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