Where is a good place for wing spacing with regards to center of gravity? On a rare few occasions I have built an airframe that effortlessly lofts into the air with a slight input. Most of the time I pull hard back until I'm 3/4 down the runway before she gets airborne. I had a problem for the longest time just not getting off the ground because of terrible stability at high rolling speeds. I'd always veer off the runway before I had a chance to get airborne. I think that had more to do with the nose wheel not facing the right way or something.