Pitch and yaw problems with kavan Fokker DR1 with ailerons
I built a Kavan Triplane that I received from my wife and kids for Christmas and added ailerons. I built it with no dihedral just like the full size triplane, the ailerons are very effective but I am experiencing problems with it in both pitch and yaw. When I apply aileron to roll it in either direction it wants to pitch nose up and yaws in the opposite direction. I have double and triple checked the CG and have modified a special batt. pack to bring the CG forward but that still hasn't solved the problem. I havn't tried offset aileron hinges yet because this would mean a major modification. If anyone out there has any experince with this kind of problem and has tried offset hinges and had any success please let me know, I don't want to start tearing the wing of my pride and joy up unless I am absolutely sure that this will solve my problem. I also have thought about adding a small vertical fin made out of clear lexan plastic so that it will add some stability in the yaw axis, I have built several larger slimer Triplanes and both of them flew good without the clear plastic vertical fin but I also increased the size of the rudder by about 15% on both of them. I have only experienced "Dutch Roll" on one other scale model ( A Corsair ) and Increasing the size of the vertical fin and rudder slightly solved the problem on it. Any Ideas? I am leaning towards the offset aileron hinges but like I said, that would mean having to cut the existing hinges and install longer ones and relocate the control horns that are epoxied in place and that will be a major pain!!!