Hang gliding is an air sport in which a pilot flies a light and unmotorized foot-launchable aircraft called a hang glider (also known as Delta plane or Deltaplane). Most modern hang gliders are made of an aluminium alloy or composite-framed fabric wing. The pilot is ensconced in a harness suspended from the airframe, and exercises control by shifting body weight in opposition to a control frame, but other devices, including modern aircraft flight control systems, may be used. In the sport's early days, pilots were restricted to gliding down small hills on low-performance hang gliders. However, modern technology gives pilots the ability to soar for hours, gain thousands of metres of altitude in thermal updrafts, perform aerobatics, and glide cross-country for hundreds of kilometres. The Fédération Aéronautique Internationale and national airspace governing organizations control some aspects of hang gliding. Gaining the safety benefits from being instructed is highly recommended.[1][2]
Starting in the 1880s technical and scientific advancements were made that led to the first truly practical gliders. Otto Lilienthal built (barely) controllable gliders in the 1890s, with which he could ridge soar. He rigorously documented his work, strongly influencing later designers; for this reason, Lilienthal is one of the best known and most influential early aviation pioneers. His aircraft was controlled by weight shift and is similar to a modern hang glider. (He was attached to the gliders by his shoulders, and swung his feet to control them.)
In the decade 1900-1910 hang gliding saw a stiffened flexible wing hang glider in 1904, when Jan Lavezzari flew a double lateen sail hang glider off Berck Beach, France. In 1910 in Breslau the triangle control frame with hang glider pilot hung behind the triangle in a hang glider was evident in a gliding club's activity.[3] The biplane hang glider was very widely publicized[4] in public magazines with plans for building; such biplane hang gliders were constructed and flown in several nations since Octave Chanute and his tailed biplane hang gliders were demonstrated. In April 1909 a how-to article by Carl S.Bates proved to be a seminal hang glider article that seemingly affected builders even of contemporary times, as several builders would have their first hang glider made from following the plan in his article.[5] Volmer Jensen with a biplane hang glider in 1940 called VJ-11 allowed safe three-axis control of a foot-launched hang glider.[6]
On November 23, 1948 Francis Rogallo and Gertrude Rogallo applied for a kite patent[7] for a fully flexible kited wing with approved claims for its stiffenings and gliding uses; the flexible wing or Rogallo wing, which in 1957 the American space agency NASA began testing in various flexible and semi-rigid configurations in order to use it as a recovery system for the Gemini space capsules. The various stiffening formats and the wing's simplicity of design and ease of construction, along with its capability of slow flight and its gentle landing characteristics, did not go unnoticed by hang glider enthusiasts. In 1960-1962 Barry Hill Palmer adapted the flexible wing concept to make foot-launched hang gliders with[8] four different control arrangements. In 1963 Mike Burns adapted the flexible wing to build a kite-hang glider he called Skiplane. In 1963, John W. Dickenson adapted the flexible wing airfoil concept to make another water-ski kite glider; for this, the Fédération Aéronautique Internationale vested Dickenson with the Hang Gliding Diploma (2006) for the invention of the modern hang glider.
