Leonardo da Vinci studied an ornithopter, a flying machine intended to imitate the flapping motion of birds.
Leonardo made extensive observations of birds and used them to investigate human flight. His proposed ornithopters included wings moved by mechanical action, with the pilot supplying force through pedals, levers, or other body-driven mechanisms. The designs reflect his belief that careful study of anatomy and natural movement could reveal principles useful for engineering.
An ornithopter differs from a glider or an airplane because its wings are meant to flap rather than remain fixed. Leonardo’s machines were never proven capable of carrying a person. Human muscles could not generate enough sustained power for the heavy wooden and fabric structures he imagined, and the control problem would have been formidable.
Although unsuccessful as aircraft, Leonardo’s studies were important in the history of aeronautical thought. He analyzed lift, drag, balance, and wing structure centuries before powered aviation. His work also helped separate observation-based flight research from purely mythical ideas about human wings.