Kites Luffing / overflying ... Why ? - Kitecrowd Kite Forum
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Thread: Kites Luffing / overflying ... Why ?

  1. #1
    •— •º–@‘¥ ‘‹•Ó Smogthemog's Avatar
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    Kites Luffing / overflying ... Why ?

    Can anyone explain what it is in the design of a ram air foil kite that makes it overfly / luff
    Can subsequent luffing be resolved by bridle modification at all
    Any help will be greatly appreciated, Thanks


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  2. #2
    Nutty as squirrel s**t the_lone_wolf's Avatar
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    overflying occurs when a kite's angle of attack is so shallow that it penetrates too far upwind and cannot keep it's shape by air pressure alone. the AoA of a kite varies with it's applications, race kites need to get as far upwind as possible so they have a very shallow angle of attack, hence are generally unstable. beginners stable kites have a high angle of attack so they sit further back in the window but don't overfly as easily. shallow AoA kites also tend to accelerate more quickly as there is less drag. they may also require more input to fly, hence are not as easy to get used to (a reason many people dismissed the blade 3 over the blade 2)
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  3. #3
    Of Course I am a Shop Owner/Worker rayens's Avatar
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    and why people have problems with razors, etc

    Its all about horses for courses

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    luffing over flying

    hi smog

    can have a quick stab at why you may be over flying

    check your brake lines are they to tight ? try slightly longer or shorten power lines, but i do say try this may or may not work

    could do with more info from yourself ie what postion kite is at what condition,s etc etc

    sorry not much help

    cheers peterpan

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    The King Off the Jungle tarzan's Avatar
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    AoA change

    You can increase angle of attack of your foil easily; shorten c-lines, say 5mm, and lengthen a-lines equally. Try if it helped; if not do it again. If it was too much, your foil won´t climb to the zenith, so go back a little.
    For the clarity; a-lines are the ones nearest to leading edge, second row is b-lines, then c-, and then brakes. >That is if there´s 4 rows of primarys in your foil...

    You can mess around your bridle lenghts freely as long as it works.
    And don´t loose original dimensions!!!
    Last edited by tarzan; 2nd April 2004 at 17:39.

  6. #6
    Beguiling Lethal Teeth Gandromedus's Avatar
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    Quote Originally Posted by peterpan
    check your brake lines are they to tight ? try slightly longer or shorten power lines, but i do say try this may or may not work
    I've heard this said before, but why do short brake lines increase luffability surely that would tend to increase the AoA, or is it due to altering the aerofoil section? Kite aerodynamics - very confusing.

    Have been playing with my Buster bridle settings and found decreased AoA increased luffing (as described above), as did attaching power rings which effectively pull the brake lines in a little. I have most luffing problems when I'm not paying enough attention and accelerate the kite too fast into the edge of the window

    Also, on the aerodynamics point, a question thats been bugging me for a while - what characteristics of a foil dictate how much lift is produced? Is it predominantly the aspect ratio, higher giving more penetration/pull at the edge of the window, or aerofoil section???

    Not a particularly useful reply I know
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  7. #7
    •— •º–@‘¥ ‘‹•Ó Smogthemog's Avatar
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    Thanks Everyone for all of your comments
    I have learnt a lot !
    Ta !


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    Action-Pact.co.uk Ally's Avatar
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    gusty ****e wind can also contribute to overfly etc.(in my experience anyway)


  9. #9
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    the main reason s most kites luff is because of gusts or bad jumps foil or other wise
    the gust of stronger wind causes the kite to fly further forward in the window.
    as soon as ths gust ceases there is nothing supportintheh kitein its new pound position so it either falls back in the window or luffs. trail a bit of brake in the gusts and it will hold the kite back in the window.