All models I've flown or seen, flaps down cause pitch up, thus calling for down elevator to correct. However, competent RC pilots have told me their planes pitch down with flaps down, requiring up elevator to correct. I've never had such a model, never seen it, and can't picture in my mind how that might happen. In U-control stunt flying, very sharp square loop corners are made with wing flaps and elevators moving counter to each other (flaps down & elevator up gives an instantaneous square inside corner).