Leonardo da Vinci’s ornithopter was a flying-machine design intended to lift a human by flapping wings.
The word ornithopter means a craft that flies through the flapping motion of wings. Leonardo studied birds and bats and produced several designs in the late fifteenth and early sixteenth centuries. His sketches explored wing shapes, frames, pedals, levers, and mechanisms that could transfer a pilot’s muscular effort to the wings.
Leonardo understood that birds use more than simple up-and-down motion: their wings change angle during the stroke. Even so, a human pilot could not generate enough power to make a machine of Leonardo’s scale fly. The proposals therefore remained studies rather than successful aircraft.
An ornithopter is different from a glider, which relies on fixed wings, and from a helicopter, which uses rotating blades. Leonardo also investigated gliding and rotating-air-screw concepts, but those belong to different parts of his aeronautical work.