By Peter Weiss
Like a bird, the world’s very first airplane had flexible wings. The lightweight wood, cloth, and wire flyer, built by Wilbur Wright and Orville Wright and first flown on Dec. 17, 1903, was steered and stabilized by pulleys and cables that twist the wingtips. Some aviation historians say that this bird-inspired control mechanism was the pivotal innovation that enabled the Wright brothers to achieve heavier-than-air flight whereas others pursuing that same goal had failed.
Although the Wright brothers’ control strategy worked, it vanished quickly from aviation. Stiff wings became the standard because they could withstand greater forces associated with increased flying speeds and vehicle weights. To control the sturdier aircraft, designers added movable panels to the ends of those stiff wings. Those panels manipulate the airflow and thus the aerodynamic forces that pilots use to make an airplane take off, turn, or change altitude.