Leonardo da Vinci designed an ornithopter, a machine intended to fly by flapping wings like a bird.
Leonardo studied bird anatomy and flight in detail, recording observations about wing movement, balance, air resistance, and the role of the tail. His ornithopter sketches show a human pilot connected to large wings through levers, pedals, and other mechanical parts. The name comes from Greek words meaning “bird” and “wing.”
The design was not a successful aircraft. A human pilot could not produce enough power through muscle alone to keep such a heavy mechanism in the air. Leonardo's later thinking increasingly considered gliding and the use of air currents, which were more realistic than powered flapping flight.
An ornithopter is different from an aerial screw: the former imitates a bird's wingbeat, while the latter uses a rotating helical surface. Modern ornithopters can fly as small experimental or model aircraft, often using lightweight materials and powered mechanisms.