Leonardo da Vinci specified linen for the cloth canopy of his pyramid-shaped parachute. In a manuscript note, he described a tent-like structure made from linen and supported by wooden poles.
Leonardo’s design was a four-sided pyramid rather than the rounded canopy associated with most modern parachutes. His notes state that a person could jump from a considerable height while protected by a structure about twelve braccia wide and twelve braccia deep. The braccia was an old Italian unit, so the exact modern conversion varies by regional standard.
The design was theoretical and was not tested by Leonardo. In 2000, British skydiver Adrian Nichols constructed and tested a version based on the drawing, using modern materials and safety procedures. The experiment demonstrated that the concept could descend, although the heavy wooden frame made landing unsafe. Leonardo’s parachute is an important early example of systematic thinking about controlled descent.