ummmm ... I thought the washout on a wing was to help stability. I like my Kat to death, but it still rocks durring a harrier .... unless it's inverted ... then it's smoothe as glass. Probably a CG thing ... or the ailerons might not be perfectly centered. I mix aileron and flap just to have the ailerons on separate channels. Comes in handy if you want to stop in mid air.