What type of flying machine did Leonardo da Vinci design by studying birds?

Leonardo da Vinci designed an ornithopter, a flying machine intended to fly by flapping wings like a bird. The word ornithopter comes from Greek roots meaning bird and wing.

Leonardo carefully observed birds and studied how their wings moved, especially during flight and gliding. His drawings show machines with large wings and mechanisms that a human pilot would operate. Some concepts used the pilot’s arms, legs, or body to power wing movement.

No Leonardo ornithopter was successfully built and flown. Human muscles cannot provide enough power for a machine of the necessary size, and the proposed mechanisms would have been too heavy. Even so, his studies helped distinguish flapping flight from gliding and rotor-based flight.