Leonardo da Vinci designed an ornithopter, a bird-inspired flying machine with wings intended to flap through human power.
Leonardo studied birds extensively and believed their wing movements could inform human flight. His ornithopter sketches show a pilot lying or standing within a frame and operating large wings through pedals, levers, or other mechanical connections. The designs reflect detailed observation of anatomy, balance, and the movement of air.
The machine was never shown to have flown. Human muscles cannot provide enough sustained power for a flapping aircraft of the proposed size, and the structure would have been difficult to control. Leonardo’s later work increasingly recognized that flight required careful treatment of weight, lift, and propulsion rather than simply copying a bird’s wings.
An ornithopter is a broad technical term for any aircraft that flies by flapping wings. Leonardo’s designs are historically important studies of powered flight, but they were not successful aircraft or direct prototypes of modern airplanes.