What is the common name for Leonardo da Vinci’s bird-inspired flying-machine design powered by flapping wings?

Leonardo da Vinci’s bird-inspired flying-machine design powered by flapping wings is commonly called Leonardo’s ornithopter.

An ornithopter is an aircraft that flies by mechanically flapping wings, imitating the motion of birds, bats, or insects. Leonardo studied birds and their wing movements extensively and produced several sketches for human-powered or mechanically assisted flapping machines during the late fifteenth century.

His drawings explored wing structures, control systems, and ways a pilot might operate the machine. They show Leonardo’s effort to treat flight as a problem of anatomy, mechanics, and air resistance. However, no complete Leonardo ornithopter is known to have been built or flown.

The word “ornithopter” describes a whole class of aircraft, not one unique Leonardo model. Leonardo also designed gliding and rotor-based machines, so his flapping-wing studies should not be confused with the aerial screw. Human muscle alone cannot provide enough sustained power for a practical aircraft of the size Leonardo envisioned.