Thanks for the info Charlie. The plane is a Bridi "Krafty 60" from BlueJay Models. It has a 60 or so inch span. It's an advanced trainer. I'm using an OS .46 AX. My radio has a flap knob, but no mixing capacity. I'll be modifying the kit to use in-wing aileron servos and will use the center wing servo for the flaps... like I did on a Senior Telemaster. The Sen. Tele. plans, however, showed where you could cut the ailerons for flaps. I'm not a hotdogger. I would just like to slow the Krafty down for landings and give it a little more lift for shorter takeoff runs. I liked the flaps on the Telemaster, but don't have enouth serious knowledge of aerodynamics to know how much flap area is enought, but not too much.