stealth916

Hi all,

I just added ailerons to a Multiplex Pico Cub given to me by a friend, along with a gear drive and new prop for the Speed 400 motor. I built this plane for him about 7 years ago or so, and it has just come back around to me. I used data which I found online in order to size the ailerons to proper cub dimensions, relative to the overall wing size.

I am using 2 servos and a Futaba 9CHPS, so I can do differential with ease. I did not remove any dihedral, because the wing was built pretty well way back, and I couldn't bring myself to saw through the kevlar wrapped spar or the fiberglass wrapped seam. I also didn't want to reshape the wing saddle, etc. Ok - lazy I know... but these mods would also take me beyond the point of no return should I decide to retreat and leave it a 3 channel ship.

This plane has a healthy dose of dihedral - sorry I don't have the exact number right now. The first few test flights indicate adverse yaw from hell. I have set end points to 140% up and 90% down on the ailerons to start, so whatever that ratio works out to be is the differential I have tried. I have also tried moving to nearly no differential, with maybe worse results. Coordinating rudder helps to a degree, but I am looking for some smoother performance. Is there any hope for this baby without getting rid of some dihedral? Should I increase differential further, by reducing the amount of down aileron to reduce the drag on the up-rolling wing panel? Should I just go with spoiler rolls? Should I consider increasing the rudder area by some percentage?

Thanks for any suggestions!