The Ornithopter - aeroplane
"Nature is the best engineer ever. And so birds must be the best aero planes ever."
An Ornithopter is a flying machine whose driving airfoils have an oscillating motion, in contrast to the rotary motion of an airplane propeller. This is similar to the wing flapping mechanism used by birds and insects to lift and propel themselves. The Golden Challenge is to build and fly a radio controlled Ornithopter.