Leonardo da Vinci (1452-1519) wrote a treatise, the Codex on the Flight of Birds, which put forth the first scientific observations on the subject of flight. He discovered the vortices that are produced off the wings, and observed the alulae, or "thumbs" of the wings. He was concerned with the center of gravity, stability, and maneuverability.
Leonardo sketched several types of flying machines: helical wing, beating wings, parachute, and bat's wings. Through real life trial and error Da Vinci learned the difficulty of realizing his great dream of flying in a machine powered by human propulsion, and turned his talents toward the problem of gliding flight. In the glider drawing below, the flyer's position is studied at the point where he is balanced through movements of the lower part of the body. The wings, modelled upon those of bats and birds of large wingspans, are fixed on the inboard portion (next to the flyer), and mobile at the external portion. This part of the wing in fact can be moved by the flyer by a control cable connected to handles. Leonardo arrived at this solution by studying the wing structure of birds and observing that the inboard part of their wings move more slowly than the outboard, and that therefore serve to thus sustain themselves and produce forward thrust.
"The great bird will take flight above the ridge...filling the universe with awe, filling all writings with its fame..."
- Leonardo on manned flight
Early Da Vinci gliders had a articulated wing with a system of belts passing between the thighs and around the body of the flyer. He later reduced the structure to a simple form with wings directly attached to the human body.
Leonardo Da Vinci: Bird's-Eye View of a Landscape. 1502.
Pen, ink and watercolor on paper. Windsor Castle, Windsor, UK
The question that always comes up regarding Leonardo and his flying machines is did they actually work. I often cite the above watercolor of a birds-eye view of a landscape as an example of Leonardo's success. Even though Leonardo was an incredible artist with an incredible mind, it is difficult to believe, after seeing the watercolor and several others like it, that he did not actually see and observe the landscape from the view dipicted. The following quote is from the "Did Leonardo Da Vinci Fly?" link below:
"Thus did Leonardo rise in the warm air current—his mouth open to relieve the pressure constantly building in his ears—until he could see the top of the mountain...it was about a thousand feet below him. The country of hills and streams and farmland and forest had diminished, had become a neatly patterned board of swirls and rectangles: proof of man's work on earth."
Leonardo's last design had a wingspan of 24 meters, nearly 80 feet, a design like no other device he had ever sketched or built. Da Vinci reached beyond nature to conceive a free-flying craft with flat surfaces to support it and a man in the still air. It had double wings, cellular open-ended boxes that was stable as box kites of like construction.
DID LEONARDO DA VINCI FLY?
A late 19th, early 20th century flying machine, a
virtual copy of the Florence Da Vinci glider. Click
to see pilot in lower wing center "Floating on the
air like a raft."
For human powered flight descriptions even earlier than Da Vinci please go to:
FLYERS BEFORE DA VINCI
RETURN TO DA VINCI FLYING MACHINES
THE DA VINCI GLIDER PAGE
PROVIDED THROUGH THE GRACEFUL SERVICES OF
The Glider History Site
(site no longer active)
Do You Think Flying in the Sky Is Magical?