Codex Atlanticus - Studies on flight

However, scientific studies on Leonardo's manuscripts, beginning right from the Codex Atlanticus, allow to downsize this myth and to discover a true evolution in Leonardo's thoughts on the theme of flight.

It is true, in fact, that he dedicated his first works on the subject to the attempt of artificial wings driven by the energy produced by a man

A subsequent phase was inaugurated by his interest in relation to the flight of birds. Leonardo studied their trajectories particularly with respect to the force of the wind, which the birds could exploit either by flying along with the wind or by opposing the wind.

The various drawings we find on this folio, sketched with great artistic effect, provide a very dynamic depiction of the various trajectories of birds' flights as they exploit various wind conditions.

The first figure in the upper left and the larger central figure, both spirals, represent the trajectory described by birds that fly "without beating their wings, but with the favor of the wind", as indicated in the caption.

By contrast, the spiral to the upper right would be a case of flight against the wind.

Lastly, further down, we find two flight trajectories that would appear to be confused together: actually, the examples shown depict, to the left, flight with weak wind, and to the right, flight with strong wind.

This folio shows a study for the construction of mechanical wings, beginning from an accurate analysis of the anatomy of birds.

The central drawing alludes to a hand or to a series of claws. In fact, the drawing shows only the mechanical skeleton, which would then have been covered with feathers.

More than a project for a flying machine as a whole, this folio shows a series of studies for the realization, by means of various devices, of the so-called instrumental flight with mechanical wings.

The four drawings have one identical mechanism in common: a screw with reverse threads, which is activated variously by handlebar, by the weight of the pilot himself, or by a crank-operated winch with a continuous cord, so as to obtain, in each case, alternating movement of the wings.

In the drawing to the lower right, for example, we see the sketch of a man operating the device.

Leonardo's caption speaks clearly of the weight of the man as a source of energy for lowering the mechanism.