I recently saw the kinetic work of seventy year old sculptor Bob Potts online. He had training in metal working but also exposure to the music world and George Rhoads according to an interview by Daniel Busby published here. Not only was I impressed by his sculpture but also the beautiful animated gifs showing his work on Colossal here.
He, like David, has been captivated by the motion of flight although his sculptures key in on the working of wings. David's flight studies have centered on the soaring aspect. Bob Potts worked with George Rhoads for 20 years before gaining enough confidence to create works of his own design. Here is a video well worth watching. The details are beautiful.