Leonardo da Vinci designed glider concepts intended to fly by using air currents rather than an engine.
His studies of bird wings led him to consider fixed-wing machines that could be launched from elevated ground and supported by moving air. Some designs included flexible wings and a human operator positioned within a frame. Leonardo’s notes addressed balance, wing shape, and the importance of wind, showing that he was moving beyond simple imitation of birds.
These concepts were not successful aircraft in the modern experimental sense. Leonardo did not have a lightweight power source, reliable control systems, or a safe method for testing human flight. A glider differs from an ornithopter because it relies on aerodynamic lift from fixed or nearly fixed wings rather than repeated flapping.
The distinction also separates a glider from a parachute. A parachute slows vertical descent, while a glider is shaped and controlled to travel through the air. Leonardo explored all three ideas as parts of his broader investigation of flight.