Leonardo da Vinci designed an ornithopter, a bird-inspired flying machine powered by flapping wings.
The word ornithopter comes from Greek roots meaning “bird” and “wing.” Leonardo studied birds extensively and filled notebooks with observations about wing shape, balance, airflow, and the movement of feathers. His proposed machine used a human operator to drive wing mechanisms, usually through pedals, cranks, or levers.
Leonardo understood that birds do not fly by simply moving rigid wings up and down. He examined how wings twist during each stroke and how birds use their tails and bodies for stability. Even so, a human-powered machine based on his designs would not have generated enough lift for sustained flight.
The ornithopter is distinct from Leonardo’s later screw-shaped aerial machine. An ornithopter imitates flapping birds, while a helicopter uses rotating blades. Leonardo’s studies influenced the history of aviation even though none of his flying machines achieved powered flight.