Leonardo da Vinci’s proposed birdlike flying machine is known as an ornithopter.
An ornithopter is an aircraft intended to fly by flapping wings rather than by using fixed wings or a rotor. Leonardo studied birds extensively and designed several mechanisms in which a human operator would move large wings through levers, pedals, or other mechanical systems.
His drawings show careful attention to wing structure, balance, and the movement of air. However, a person cannot provide enough power to flap wings large enough to lift a human body, so Leonardo’s ornithopters were never practical aircraft. Modern ornithopters have flown as small experimental or model machines.
The term comes from Greek words meaning “bird” and “wing.” It should not be confused with Leonardo’s aerial screw, which uses rotary motion, or his parachute, which depends on drag during descent. Leonardo’s work remains an important early attempt to turn observations of animal flight into an engineered machine.