Leonardo da Vinci designed ornithopters that attempted to imitate a bird’s flapping flight.
An ornithopter is a flying machine that generates lift through the movement of wings rather than through continuously rotating propellers. Leonardo studied bird anatomy, wing structure, and the movement of air while developing several concepts for human-powered flight. His drawings include machines with large wings operated by a person using levers, pedals, or other mechanical linkages.
Leonardo understood that human muscles alone were unlikely to power a sufficiently large machine in the same way a bird’s muscles power its wings. For that reason, his ornithopters remained experimental designs and were never proven to fly. They also differ from his aerial screw, which sought vertical lift through rotation.
The word comes from Greek roots meaning “bird” and “wing.” Modern ornithopters have been built as small remote-controlled aircraft, but Leonardo’s Renaissance designs were studies in biomechanics and aerodynamics rather than working airplanes.