Leonardo da Vinci designed an ornithopter, a powered flying machine modeled on the flapping wings of birds.
The word ornithopter comes from Greek roots meaning “bird” and “wing.” Leonardo’s versions generally used a human pilot lying or standing inside a frame and operating wings through pedals, handles, or other mechanical linkages. His notebooks show careful observations of birds and bats, along with studies of wing structure and airflow.
The design was ingenious but would not have given a human enough power to fly by flapping large wings. Human muscles cannot produce the same power-to-weight ratio as the flight muscles of birds. For that reason, Leonardo’s ornithopter remained a concept rather than a successful aircraft.
It is often confused with Leonardo’s glider designs. A glider uses fixed wings and gains lift while moving through air; an ornithopter seeks lift through repeated wing motion. Leonardo investigated both approaches during his studies of flight.