George Cayley Engraves Fixed-Wing Aircraft Design on Silver Disc

In 1799, English baronet Sir George Cayley engraved a silver disc depicting an aircraft with a fixed wing, boatlike fuselage, cruciform tail, and flappers for propulsion. The reverse showed a diagram of aerodynamic forces acting on a wing. This was the earliest known design to separate lift, propulsion, and control into distinct systems, departing from prior ornithopter concepts that attempted to mimic bird flight. Cayley subsequently built a model glider in 1804 and a full-scale glider that carried a passenger across Brompton Dale in 1853.