Leonardo da Vinci designed glider-like aircraft with rigid wings and a harness for the pilot.
Unlike his flapping-wing ornithopters, these designs relied on aerodynamic lift generated as the aircraft moved through the air. Leonardo studied bird wings and proposed ways for a pilot to control balance and direction while descending or riding air currents. His sketches include wing shapes and frameworks rather than a proven, flight-tested aircraft.
A glider has no engine and cannot maintain powered level flight by itself. It differs from an ornithopter, which tries to produce propulsion through flapping, and from an aerial screw, which uses rotating surfaces. Leonardo’s drawings show that he explored several competing approaches to flight.
The glider concept was scientifically promising but technologically premature. Renaissance materials, knowledge of airflow, and human strength were insufficient to make a safe, controllable aircraft of the type Leonardo imagined.