Zenith "no hinge ailerons"

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by cheapracer, Nov 12, 2019.

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  1. Nov 17, 2019 #41

    BBerson

    BBerson

    BBerson

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    Sure, but that is bending it way past yield each time to break it in only six flexes.
    For life below yield, look up the S/N curve for aluminum.
     
  2. Nov 17, 2019 #42

    Mad MAC

    Mad MAC

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    Its a pity zenith air didn't use standard terminology
    http://www.zenithair.com/kit-data/ht-aileron.html
    It should be pointed out that the usual scatter correction factor is 1/6 for fatigue data, its not clear this has been applied to get the 120,000 cycles. Plus they don't address the biggest deviation from the standard test data, which is the shear load in addition to the bending.

    Interestingly the design would be quite sensitive to where the surface movement comes from i.e. vertical movement of a bell crank, horizontal motion of the a push rod and were that point is on the surface (well away from the ends would make a big improvement).

    It may actually help suppress flutter, if the extra degree freedom can be set to result in non liner movement in the critical case.
     
  3. Nov 17, 2019 #43

    Pops

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    The Zenith 600 project that I had ( From first plans) had piano hinges. Plans showed a 1835 cc, VW engine.
     
  4. Nov 17, 2019 #44

    BBerson

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    Yes, I would be more concerned with overall stiffness, which could effect flutter if not stiff.
     
  5. Nov 17, 2019 #45

    Himat

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    There is also a difference between manned and radio control sailplanes that can be significant. In a manned airplane aerodynamic and/or inertial forces may overpower the pilot and shift the position of a control surface. On a radio-controlled plane with correct sized servos the control surfaces are stick fixed and do not overpower the servos.
     
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  6. Nov 17, 2019 #46

    litespeed

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    I think he noticed the Goat on the side, and having a penchant for the beasts, got hungry. Jack must have figured he got lucky. No need to climb and drop it from height to tenderise.

    Just scare the meat bag flying and he will do all the work for you.

    Just bloody lucky Emus don't fly and Kangaroos have no wings.
    And don't even mention any local snakes on a plane.

    Mother nature sure takes a grudge around here.
     
  7. Nov 18, 2019 #47

    pictsidhe

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    Shouldn't that be:

    'As a bloody Aussie, Mate,'
     
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  8. Nov 18, 2019 #48

    pictsidhe

    pictsidhe

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    Heinz's fatigue test didn't account for binding or shear. It's those that make it a lot more complex to analyse. May as well just set up a test rig that does include them than struggle with the maths.
     

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