Leonardo da Vinci’s ornithopter designs were intended to imitate the flight of birds and bats.
An ornithopter is an aircraft designed to fly by flapping wings. Leonardo studied birds, bats, and the mechanics of wing movement extensively, producing sketches of human-powered flying machines with wings that moved up and down. His observations helped him think about lift, balance, and the relationship between wing shape and motion.
Leonardo’s machines were never successfully flown by a person. Human muscles could not provide enough sustained power for the proposed wing area, and the designs did not fully solve problems of weight, control, and propulsion. Some drawings resemble bird wings, while others reflect the membrane wings of bats.
The term ornithopter does not mean that the aircraft must copy only birds. It describes the flapping-wing method itself. Leonardo’s work is therefore part of the long history of biomimicry, even though powered human flight ultimately developed through fixed wings and engines.