Parachuting

Parachuting, also known as skydiving, is the sport of jumping from enough height to deploy a fabric parachute and land safely. The history of parachuting appears to start with Andre-Jacques Garnerin who made successful parachute jumps from a hot-air balloon in 1797. The military developed parachuting technology first as a way to save aircrews from emergencies aboard balloons and aircraft in flight, later as a way of delivering soldiers to the battlefield. Early competitions date back to the 1930s, and it became an international sport in 1951.

In the early days, a trained skydiver (or jumper) and a group of associates met at an isolated airport, sometimes referred to as a "drop zone." (DZ) A fixed base operator at that airport usually operates one or more aircraft, and takes groups of skydivers up for a fee. It was common for an individual jumper to go up in a Cessna light aircraft such as C-172 or C-182. These days, it is common for busier DZs near populated areas to use multiple, larger aircraft such as the Cessna Caravan C208, De Havilland Twin Otter DHC6 or Short Skyvan.

A typical jump involves individuals jumping out of an aircraft (usually an airplane, but sometimes a helicopter or even the gondola of a balloon), at approximately 4,000 meters (around 13,000 feet) altitude, and free-falling for a period of time before activating a parachute to slow the landing down to safe speeds. Once the parachute is opened, (usually the parachute will be fully inflated by 2,500 ft). the jumper can control his or her direction and speed with toggles on the end of steering lines attached to the trailing edge of the parachute, and so he or she can aim for the landing site and come to a relatively gentle stop in a safe landing environment. By manipulating the shape of the body—as a pilot manipulates the shape of his aircraft's wings—a skydiver can generate turns, forward motion, backwards motion, and even lift. Experienced skydivers say that in freefall one can do anything a bird can do, except go back up.

When leaving an aircraft, for a few seconds a skydiver continues to travel forwards as well as down, due to the momentum created by the plane's speed (known as throw-forward). The perception of a change from horizontal to vertical flight is known as the "relative wind", or informally as "being on the hill".