This is my second biplane. The first being the GP Stearman and it had no trim problems like the BH Pitts. The instruction manual for the Pitts provided no information on incidence angles nor did the manual supplied by GP. I assumed the engineers did their home work for the modeler. We all no what assumptions can and do make and ass out of you and me. The only modification I made to the Pitts was moved the CG back torward the TE of the top wing. I did this because their location would make the plane extremely nose heavy. I'll guess I'll live with this problem because there is no way you can reconfigure the mounting of the top wing assembly.