This image is a sketch of a proposed machine for human flight depicted in the Codex on the Flight of Birds. The Helicopter was not da Vinci’s only attempt at exploring flight. Da Vinci’s fascination with flight included both human flight and the flight of birds. Between 1505 and 1506, da Vinci produced the Codex on the Flight of Birds. This work included observations about the physics behind the flight of individual species of birds. The human flight device pictured here uses the physical concept of pressure differentials seen on the wings of birds and attempts to apply this principle to a machine allow for human flight. Like the helicopter, this device would work in theory, however the machine was much too heavy to work with human power alone. After his death, da Vinci’s Codex was traded around through Europe before being restored to its completed form and stored in the Royal Library in Torino.

Source:

Smithsonian National Air and Space Museum. “Leonardo Da Vinci's Codex on the Flight of Birds.” Leonardo Da Vinci's Codex on the Flight of Birds | National Air and Space Museum, 22 Oct. 2013, airandspace.si.edu/exhibitions/codex/.