Excess Aileron sensitivity around neutral

[Grow Pattern]

Paul,
         What is the mechanical advantage ratio like between the servo arm and the aileron horn?  A long aileron-servo arm and a short aileron horn can make for some bad resolution under load. Many servos do not deliver if loaded incorrectly. Also what is the voltage of your battery under a 500 mA load?

Eric.
 
  ----- Original Message ----- 
  From: jivey61 at bellsouth.net 
  To: discussion at nsrca.org 
  Sent: Monday, December 05, 2005 12:01 PM
  Subject: Re: Excess Aileron sensitivity around neutral


  Paul
   I think you have too much throw on the ailerons.You should look for maximum of 12-15 degrees up and 12-15 degrees down as measured with a gage of some sort. Seal aileron gap,also.

  Jim Ivey 
    ----- Original Message ----- 
    From: paul 
    To: discussion at nsrca.org 
    Sent: Monday, December 05, 2005 11:10 AM
    Subject: Re: Excess Aileron sensitivity around neutral


        Oops, when I said the ailerons were OK at full throttle I meant to describe that the aileron authority was not excessive, not that the excessive sensitivity is speed or throttle related - it is not.  Sorry I was not more specific.
        Some more details:
    * Servos are two digital 9252s, should be plenty of torque and have excellent resolution around neutral - no pot problems.
    * Linkage is carbon fiber rod and no slop.
    * Expo is - 45% to reduce the twich.  ATV is 100 % high rate 90% low 75% (normally high would be 100% but is dialed down while working this problem).
    * Airframe - no loose covering, clevis pin is over hinge line at neutral, servo arm and control horn are 90 degrees at neutral (control geometry).  CG is rearward but not tail heavy - pitch is not twichy. 
    * have not measured  wing and stab incidence angles.

    *** one thing that Del mentioned - Aileron trailing edge (and wing) taper to a very sharp radius ~ 3/32 to 1/8 inch.

    Thanks,
    Paul
      ----- Original Message ----- 
      From: paul 
      To: discussion at nsrca.org 
      Sent: Sunday, December 04, 2005 5:26 PM
      Subject: Excess Aileron sensitivity around neutral


          I have a Meridian with a frustrating characteristic, the ailerons are excessively sensitive around neutral.
      I'm the second owner of this plane but the first owner said he had the same problem.  Aileron authority at full throttle is not excessive - in fact it slightly on the mild side.    
      Any ideas ?
      Thanks,
      Paul
      NSRCA 3606
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.f3a.us/pipermail/nsrca-discussion/attachments/20051205/040931a0/attachment.html