The Wright brothers began by accumulating and mastering all the important information on the subject, designed and tested their own models and gliders, built their own engine, and, when the experimental data they had inherited appeared to be inadequate or wrong, they conducted new and more thorough experiments. The Wrights decided that earlier attempts at flight were not successful because the plans for early airplanes required pilots to shift their bodies to control the plane. The brothers decided that it would be better to control a plane by moving its wings.