Leonardo da Vinci’s ornithopter was a flying-machine design that used flapping wings to imitate birds.
Leonardo studied birds, bats, and the mechanics of wings for much of his life. His notebooks contain several ornithopter concepts, including machines in which a pilot would move wing structures through pedals, levers, or other mechanical systems.
An ornithopter is defined by flapping flight, not by the identity of its designer. Leonardo’s versions were never demonstrated successfully, because a human pilot could not supply the power needed for sustained bird-like flight with Renaissance materials.
The concept differs from Leonardo’s aerial screw, which sought vertical lift from a rotating spiral. It also differs from gliders, which rely on fixed wings and forward motion. Modern ornithopters have been built, but Leonardo’s designs remained studies and proposals rather than functioning aircraft.