Leonardo da Vinci’s wing-flapping aircraft design is called an ornithopter.
An ornithopter is an aircraft that produces lift and thrust by flapping wings, rather than by using fixed wings and a propeller. Leonardo studied birds and bats and drew several concepts in which a human pilot would move large wings through pedals, levers, or other mechanical controls.
His sketches show careful attention to anatomy, airflow, wing structure, and the relationship between weight and muscle power. The designs were inventive, but a human pilot would not have had enough power to flap wings of the necessary size for sustained flight.
Leonardo’s ornithopters were therefore theoretical machines rather than successful aircraft. They are still important in the history of aviation because they demonstrate his systematic attempt to understand flight through observation and mechanical design.