Leonardo da Vinci sketched a pyramid-shaped parachute as a device for slowing a person's descent.
Around 1485, Leonardo recorded the design in the Codex Atlanticus. His drawing shows a rigid wooden frame covered with linen cloth, forming a pyramid about 7.2 metres wide and high. Leonardo reasoned that a person could jump safely from a great height if the structure created enough air resistance.
The design was theoretical rather than a tested flight machine. Leonardo did not build a full-size parachute, and his proposal differs from modern parachutes, which use flexible canopies and suspension lines. The pyramid shape is nevertheless based on a correct aerodynamic principle: increasing drag reduces falling speed.
A full-scale replica was tested in modern times, although its rigid structure was considered dangerous for landing. The device is often called Leonardo's parachute, not the first practical parachute; that distinction belongs to much later experiments and designs.