Leonardo da Vinci sketched glider-like aircraft with fixed wings that did not flap.
A glider is an aircraft that flies without an engine, using aerodynamic lift and descending gradually through the air. Leonardo’s flight studies included winged designs influenced by birds, but some of his concepts relied on broad, relatively fixed surfaces rather than continuous flapping.
Leonardo’s notebooks show that he was trying to understand how air supports a body. He examined bird flight, wind, balance, and the shape of wings. His designs were not modern gliders in the engineering sense: they lacked tested materials, reliable control systems, and a practical launch method.
The term ornithopter is a common mix-up because Leonardo is strongly associated with flapping-wing machines. The distinction is simple: an ornithopter uses flapping motion, while a glider depends on fixed wings and moving air. Leonardo’s drawings helped anticipate both lines of aviation thinking.