Leonardo da Vinci studied an ornithopter, a flying machine intended to imitate the flapping motion of a bird’s wings.
Leonardo made many observations of birds and used them to explore human flight. His ornithopter concepts generally placed a person inside or beneath a lightweight frame connected to large wings. The pilot would operate pedals, levers, or other mechanisms to transmit movement to the wings.
An ornithopter is different from a glider, which gains lift from forward motion with fixed wings, and from an aerial screw, which uses rotating blades. Leonardo’s flapping-wing designs were not powered by an engine; they depended on human muscle. Human power is insufficient to operate wings of the required size and strength for sustained flight, so these designs were not practical aircraft.
Even so, Leonardo’s studies contributed careful observations about lift, balance, wing structure, and the relationship between bird anatomy and mechanical design. His notebooks show investigation rather than a successfully flown machine.