kzart

I have an airfoilz yak, when I plug the battery up the ailerons flutter violently(4" of throw up and down), but it flies great. Air from the prop alone stops the fluttering (1/8 throttle)....shouldI be concerned?

jzrf6c

Only if you don't want to crash.

TedMo

4" of throw?? Concerned?? Think you better do some reading here in forums.

lejongleur

My Feedback: (10)

If there is only one servo for the ailerons, changing the servo should fix the problem. If there is a servo for each wing, and they are both fluttering, it's probably some problem with the receiver. My advice is don't screw around if it's a servo - just replace it, don't try and mess around to see if "will get better". Small servos are cheap, and you will not be able to do much if it sticks in an unfortunate position whilst you are flying.

kzart

well thats the thing, it flies awesome. holds knife edge. flies level and slow. only happens while sitting still. woundering if its some epp bounce or springiness...or servo center slightly off of relaxed control surface center (hinge bind)?

Doc Austin

Sounds like the potentiometer in the servo is burnt. The problem is only going to get worse. Replace the servo and I am betting it stops.

kzart

dual servos by the way = bounce

Jezmo

There is natural harmonic occurring between the aileron and servo. The problem is either springiness in the linkage or the servo is too small to hold center. Could also be the dead band in the servo is not set up right but most likely it is the lack of rigidity in the linkage. Will it hurt it? Likely not in the short term but over time the constant movement on the ground will cause undue wear on the servo's motor, potentiometer, and gear train. How long will it hold up to the stress? Anyone's guess.

Of course this is IMHO.

Rodney

Another possibility, it seems like you have very large ailerons. If so, do you have them statically balanced? If not, it may be that the weight of the servos tends to overpower the servo so that between pulses to the servo, the ailerons droop then, as pulses are applied, the servo pulls them back up. Since you are only powering the servo up about 20 times per second for a few milliseconds, the gravity pulls the ailerons down when the power is off. To see if this is the case, hold the plane with nose straight up (negates the pull of gravity on the ailerons) and see if it oscillates or jitters then. If not, just statically balance the ailerons to cure the problem.