Leonardo da Vinci’s human-powered flapping-flight design is an ornithopter.
The word ornithopter means a machine that flies by flapping wings, from Greek words associated with bird and wing. Leonardo studied birds extensively and produced several drawings of winged machines during the late fifteenth and early sixteenth centuries. His designs generally placed a person in a frame connected to large wings, with the pilot expected to provide power through pedals, levers, or other movements.
Leonardo understood that birds use more than simple up-and-down motion. His notes considered wing shape, feathers, balance, and the movement of air. Even so, a human could not generate enough power to flap wings of the required size and lift a complete machine from the ground.
An ornithopter is not the same as Leonardo’s aerial screw. The aerial screw sought vertical lift from a rotating helical surface, whereas an ornithopter sought lift from flapping wings. Leonardo’s studies helped shape the history of flight, but none is known to have flown successfully during his lifetime.