Leonardo da Vinci’s bird-inspired flapping-wing flying machine was an ornithopter. The word combines Greek terms for bird and wing, and describes an aircraft that gains lift by moving wings up and down, like a bird or insect.
Leonardo filled his notebooks with anatomical studies of birds and observations of their wing beats. His designs placed a pilot in a frame who would operate wings through pedals, levers, and pulleys. Human muscle power, however, is not sufficient to make a practical flapping aircraft of the size he imagined.
Leonardo’s ornithopter was never built as a successful aircraft. It remains important because it shows how Renaissance engineers tried to copy biological mechanisms. Modern ornithopters, including small unmanned aircraft, use motors rather than a person’s muscles. The design is often confused with Leonardo’s glider, which used fixed wings and relied on aerodynamic lift rather than flapping.