The traditional parachute canopy takes the form of an umbrella, from which a series of cords converge downward to a harness strapped to the user; modern parachutes are wing-shaped, allowing precise control by the parachutist. By pulling on the appropriate control cords, the parachutist can spill air out of one side or another, and increase or decrease the lift of the wing, thus turning, diving, or even hovering under favorable conditions. Folding a parachute canopy requires a high degree of skill, and an improperly folded chute will not open. Before the parachute can be opened, the user must be clear of the aircraft in order to avoid entanglement, or fouling. Finally, the harness must be easily detachable, or else the parachutist might be drowned or dragged along the ground. The rate of descent for a traditional parachute is about 18 ft (5.5 m) per sec. A French aeronaut, Jean Pierre Blanchard, claimed the invention of the parachute in 1785, and the first successful parachute descent from a great height was made in 1797 by the French aeronaut Jacques Garnerin, who dropped 3,000 ft (920 m) from a balloon. Parachutes began as an escape system for persons aboard balloons or aircraft unable to land safely.
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