What type of mechanical bird did Leonardo da Vinci design to flap its wings with a human-powered mechanism?

Leonardo da Vinci designed a mechanical ornithopter intended to flap its wings through a human-powered mechanism.

Leonardo’s flying-machine studies included a large winged apparatus operated by pedals, levers, and a crank-like system. The pilot’s legs and arms were meant to drive the wings, imitating the motion of a bird. His surviving sketches show that he was trying to translate biological movement into a repeatable mechanical action.

The concept was limited by the power available from a human body. A person could not generate enough sustained energy to lift the machine and maintain controlled flight, especially given the weight of the frame and wings. Leonardo’s own observations of birds also led him toward gliding and other flight studies rather than a successful powered ornithopter.

A mechanical ornithopter is distinct from an aerial screw: the former uses flapping wings, while the latter uses a rotating helical surface. Neither design became a working aircraft in Leonardo’s lifetime.