Good luck aeajr, Spirit is a good design. Skybench (Ray Hayes) makes beautiful airplanes also. I think spoilers are the way to go, over flaps. I will be" spoiling" my Bird of Time arf. It's been too many years since I flew a two channel glider. I found the Graupner plastic spoilers from Hobby Lobby to be usable; a Hitec 55 will find its way into each wing of the BOT. Jim B LSF796