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Thursday, September 28, 2017


    David Barish often gets credit for inventing paragliding back in the early 1960s. At the time he was developing a space capsule recovery device for NASA and tested his work personally in 1965 on Hunter Mountain, New York; his term for it was “slope soaring.” His invention's inspiration was the earlier work of Domina Jalbert, an American who helped to advance airfoil technology and subsequently patented the Parafoil in 1963. The Parafoil was a ram-air design incorporating a row of inflatable air pockets into an airfoil shape.
     At about the same time climbers in the French Alps were utilizing similar technology. After reaching the summit they would descend safely and efficiently using small ram-air canopies to float down. By the mid-1980s, the focus was on maximizing the flight potential of rising air, which was found to be the secret in increasing the duration of flights and covering longer distances.
     The wing is usually what is known as a "ram-air airfoil". They consist of two layers of fabric that are connected to internal supporting material that form a row of cells. By leaving most of the cells open only at the leading edge, incoming air keeps the wing inflated, thus maintaining its shape. When inflated, the wing's cross-section has the typical teardrop shape. The pilot is supported by a network of suspension lines and a harness.

     Advances in design in the 1980s that improved performance included: increased wingspan, the introduction of nonporous fabric and modifying the shape and trim of the airfoil. These design changes meant changes in the flight characteristics and new techniques were needed to pilot them. By 1986 the sport was well established in Europe.
     For a long time development and marketing of paragliders in the USA had been restricted to three manufacturers of skydiving equipment, but they lacked the performance of the European designs. Eventually the wings became classified into different groups, according to their usage. There were different canopies designed for student pilots, intermediate (recreational) pilots, and competition pilots.
     As paragliding evolved, the sport eventually separated into two different sports: skydiving and paragliding. Wings are nonporous, elliptical shaped, and have thin-profile airfoils which allow higher speeds, better glide performance, and greater efficiency. These features, which were developed for paragliders, are now being incorporated into skydiving parachutes.
     Paraglider flights can last many hours and cover many hundreds of kilometers, though flights of one to two hours and covering some tens of kilometers are more the norm. By skillful exploitation of sources of lift, the pilot may gain height, often climbing to altitudes of a several thousand feet.
     Most pilots use several instruments. A variometer helps a pilot find and stay in a thermal to maximize height gain and to indicate when a pilot is in sinking air and needs to find rising air. Humans can sense the acceleration when they first hit a thermal, but cannot detect the difference between constant rising air and constant sinking air.
     Radio communications are used in training, to communicate with other pilots, and to report where and when they intend to land. Some flight clubs offer automated weather updates and in rare cases pilots can to talk to airport control towers or air traffic controllers. Many also pilots carry a cell phones for emergency use.
     GPS is a necessary accessory when flying competitions where it has to be demonstrated that way-points have been correctly passed. The recorded GPS track of a flight can be used to analyze flying technique or can be shared with other pilots. GPS is also used to determine drift due to the prevailing wind when flying at altitude, providing position information to allow restricted airspace to be avoided and identifying one’s location for retrieval teams after landing out in unfamiliar territory. GPS is sometimes integrated with the variometer.
     Launching and landing are done into wind either by running or being towed or a blowing wind. The pilot is then lifted from the ground and, after a safety period, can sit down into his harness. In low winds the wing is inflated as the pilot runs forward with the wing behind so that the air pressure generated by the forward movement inflates the wing. In higher winds, a reverse launch is used, with the pilot facing the wing to bring it up into a flying position, then turning around under the wing and running to complete the launch. In flatter countryside, pilots can also be launched with a tow which can launch pilots up to 3000 feet altitude.
     Brakes held in each of the pilot’s hands connect to the trailing edge of the left and right sides of the wing and provide the primary and most general means of control. They are used to adjust speed, to steer (in addition to weight shift), and to flare during landing. In addition to manipulating the brakes, a pilot must also lean in order to steer properly.
     A kind of foot control called the "speed bar" attaches to the paragliding harness and connects to the leading edge of the paraglider wing, usually through a system of at least two pulleys. This control is used to increase speed by decreasing the wing's angle of attack. More advanced control can be obtained by manipulating the paraglider's risers or lines directly.
     Landing a paraglider involves some specific techniques and traffic patterns. Pilots normally lose altitude by flying a figure-8 over landing zone until the correct height is achieved, then line up into the wind and give the glider full speed. Once the correct height (about a 3 feet above ground) is achieved the pilot will flare the wing to minimize vertical and/or horizontal speed.
     Since the shape of the wing is formed by the moving air entering and inflating the wing, in turbulent air, part or all of the wing can collapse. On modern recreational wings if this happens, normally recovery without pilot intervention is done. In the event of a severe deflation, correct pilot input will speed recovery from a deflation, but incorrect pilot input may slow the return of the glider to normal flight, so pilot training and practice in correct response is necessary.
     It it is not possible to recover from a deflation most pilots carry a reserve parachute, but should a wing deflation occur at low altitude, recovery may not be possible. A reserve parachute normally requires 200 feet of altitude.

World records:
Straight Distance - 350.6 miles
Highest flight – 26,762 ft
Oldest female paraglider - Peggy McAlpine at the age of 104.

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