whats right for the kougar
 

i have a 46 ax with tuned pipe on my kougar with an APC 10x7. i'm getting aileron flutter and i'm only at about 70 i'm guessing. i have the bottom of my ailerons sealed with monocoat. what can i do to make this thing go faster and also lose the flutter. lost to many airplanes because of flutter.

RE: whats right for the kougar
 

Aileron flutter can be caused by several things. First make sure there is no play in the linkage. The leading edge of the aileron should be as thick or thicker then the trailing edge of the wing where it mates. If it isn't or there is too much bevel from sanding you may need to do more then just seal. On my Shrike I used MonoKote and CA to secure a strip of 1/64 ply to the trailing edge of the wing and had it lay over the aileron. This got rid of flutter when everything else failed.

I had a Kougar in 1980. It is a 40 size, right? I would drop down to a 9x8 or 9x9 prop.

RE: whats right for the kougar
 

Dirtmagnet:

If your linkage is tight, and it's still fluttering, run another strip of monocote on the opposite side of the seal you now have. Should stiffen things up enough. If not, better replace the ailerons with med-heavy balsa stock and keep the gap tight. You should have a minimum of 4 hinges in each aileron, I try to get 5 in just for this reason. Can be tough to figure out some times. On several of mine, thought the centering os the hinges were off enough to really be a problem. Nope, some times logic just escapes us. ENJOY

RE: whats right for the kougar
 

yes the kougar is 40 size. i have a 9x8 master airscrew and a 8x10 apc and 8.75x7.75 pylon. the linkages are tight. i'll try sealing the other side of the hinge. if thaat dont work i'll try adding weight to the aileron or getting heavier ones. i love the plane not just for speed but i know it will go fast cause i seen em. so if i know it will do it i make it. thanks for the advice.

RE: whats right for the kougar
 

I have had tremendous success with simple CA hinges in most of my planes. Sometimes doubling them which makes the control surface very stiff instead of very smooth and loose like Robart hinges or similar. To me, this is what is preventing me from getting any flutter anywhere. I guess it wouldn't matter if you were doing aerobatics or flying in a non speed environment.

RE: whats right for the kougar
 

One of the pylon guys was saying to just pin the outside end of the aileron to get a similar effect.

The clevis being mounted too close to the control surface is another thing to avoid from a flutter stand point.

RE: whats right for the kougar
 

ok i'll try anything i can to keep tis from happening. lost to many airplanes because of this problem. i do fly alot of aerobatics but mostly got this plane to go fast. if i have to i'll put a higher torque servo on there. i just want to get up to 100 mphif not faster without any structural damage to the airplane.