Hang gliding is an air sport employing a foot-launchable aircraft. Typically, a modern hang glider is constructed 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.
Overview
Early hang glider designs did not reliably achieve safe flight, their builders lacking a comprehensive understanding of the underlying principles of flight. The first recorded controlled flights were by German engineer Otto Lilienthal, whose research, published in 1889, strongly influenced later designers. The type of aircraft employed by Lilienthal is now referred to as a hang glider. Further hang glider research was undertaken during the 1920s in Europe, Australia and the US, where designers tested several wing concepts and the 'pendulum weight-shift control system'.
In 1957 the American space agency NASA began testing various formats of a new wing called the Rogallo wing with the intent of possibly implementing the design as a recovery system for the Gemini space capsules. The wing's simplicity of design and ease of construction, in combination with its slow flight characteristics, did not go unnoticed by hang glider enthusiasts; Rogallo's flexible wing airfoil was soon adapted by John Wallace Dickenson in 1963, to the purpose of recreational flight, launching a hang glider renaissance.
Early history
George Cayley constructed a slope-launched glider that flew with a pilot in 1853. Starting in the 1880s, advancements were made in aerodynamics and construction that led to the first truly practical gliders; this information was often shared and published by early aviators and inventors, building a long series of incremental achievements. Through the 1880s, several aviation pioneers emerged in different countries around the world, and they all pursued glider designs with varying degrees of success. Chief among these were Otto Lilienthal in Berlin, Germany, Lawrence Hargrave in Sydney, New South Wales in Australia, Percy Pilcher in the United Kingdom, John Joseph Montgomery at Otay Mesa near San Diego, California (1880s) as well as at Santa Clara, California (1905) Octave Chanute and his team in Gary, Indiana, in the US, to name but a few.
Otto Lilienthal duplicated some of his contemporaries' work and greatly expanded on it from 1874, publishing all of his research in 1889. He also produced a series of gliders, and in 1891 was able to make controlled flights of or more routinely, as well as some soaring flights. He rigorously documented his work, influencing later designers; for this reason he is one of the best known and most influential of the early aviation pioneers. His type of aircraft is now known as a hang glider. By 1896, he had made about 2,000 flights of with a number of his designs when he crashed from a height of about , fracturing his spine.
Percy Pilcher took a growing interest in aviation and built a glider called The Bat which he flew for the first time in 1895. Later that year Pilcher met and consulted with Otto Lilienthal, who was the leading expert in gliding; these discussions led to Pilcher building two more hang gliders, The Beetle and The Gull. Based on the work of his mentor Otto Lilienthal, in 1897 Pilcher built a third hang glider called The Hawk with which he broke the world distance record when he flew .