Leonardo da Vinci designed an ornithopter intended to help a person fly by flapping wings.
An ornithopter is an aircraft that generates lift through the motion of wings, imitating birds or bats. Leonardo studied bird anatomy and flight and produced several sketches for flapping-wing machines during the late 15th and early 16th centuries.
His drawings show mechanisms that would transfer the pilot’s movements to large wings. The designs demonstrate careful observation of flight, but a human-powered machine of this type could not provide enough power with Renaissance materials and muscle strength.
Leonardo also explored gliding and other flight concepts, so not every flying-machine sketch is an ornithopter. The term specifically refers to flapping-wing flight. Modern ornithopters have been built as models and experimental aircraft, but they remain distinct from conventional airplanes and helicopters.