Leonardo da Vinci’s bird-inspired flying machine was an ornithopter, a craft intended to fly by flapping wings.
The word ornithopter combines Greek roots meaning “bird” and “wing.” Leonardo studied birds closely and filled notebooks with observations about lift, balance, wing movement, and air resistance. His proposed machines generally used a human operator to power or control wing mechanisms.
Leonardo’s ornithopters were never demonstrated as successful aircraft. Human muscles cannot provide enough sustained power for a large flapping machine of the type he imagined. However, his investigations helped connect artistic observation with systematic mechanical analysis.
The ornithopter should not be confused with Leonardo’s screw-like aerial machine, which is often called a helicopter precursor, or with his parachute, which depends on drag rather than powered flight. Modern ornithopters have been built, especially as small experimental or model aircraft, but they use modern materials and power systems.