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 enable reliable 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. That same year, similar designs were also successfully employed in Calabria, Italy by aeronautics inventor and artist, Vincenzo Raschella. The types of aircraft employed by Lilienthal and Raschella are now referred to as hang gliders. 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.Low & Slow magazine produced by Joe Faust (1971) was the most powerful publicity tool during the early years. He followed Low & Slow with Hang Glider Weekly to reach 23 nations through 1981 with 216 editions. Joe's publications were written by a staff of scores of correspondents worldwide. A monthly publication, Ground Skimmer was started in May 1972 as a newsletter for club members in California. It soon grew to be a comprehensive magazine, recording the history of the hang gliding movement as it happened. By the end of 1973, the organization had become truly national in scope and in November 1976, the name of the magazine was changed to Hang Gliding. Glider Rider also appeared. In 2002, Hang Gliding and Paragliding magazines were combined and the resulting magazine was named Hang Gliding & Paragliding magazine.
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; Vincenzo Raschella in Calabria, Italy; Lawrence Hargrave in Sydney, 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.The Flight of Birds as a Basis of Aviation. ; 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.Pilcher's gliders. First-to-fly.com. Retrieved November 29, 2011. 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 .Percy Pilcher. Spartacus-Educational.com. Retrieved February 27, 2019.
Wasserkuppe The hang glider lost some importance from the introduction of wing warping in 1902 by the Wright brothers and subsequently of aileron control by the French. When World War 1 ended in 1918, the Treaty of Versailles practically ended engine-driven flights in Germany, thus, in the 1920s and 1930s, while aviators and aircraft makers in the rest of the world were working to improve the performance of powered aircraft, the Germans were designing, developing and flying ever more efficient gliders and discovering ways of using the natural air flows in the atmosphere to make them fly farther and faster. These activities on Wasserkuppe promoted a renaissance of gliding aviation. Many of these gliders flown in 1920 were hang gliders in that they were controlled by the pilot's weight shift alone. The first Wasserkuppe glider competition was held in 1920, and from 1924 they were organised by Rhön-Rossitten Gesellschaft. Over the next decade, the contest grew in popularity. As many as 70 glider clubs from Europe sent their best gliders and pilots to compete for duration, altitude and distance prizes, the most coveted prize was that donated by President Paul von Hindenburg. As many as 60,000 spectators dotted the mountain slopes to watch these events.Spectators at Wasserkuppe. Webcitation.org. Retrieved November 29, 2011. Virtually every European aeronautical engineer of the time tested and modified their aircraft there and reports were generated.Glider Construction and Design from Der Gleit and Segelflugzeugbau, 1925. (Translated to English): Some competing hang glider designers were Alfried Gymnich,Alfried Gymnich. Ntrs.nasa.gov (October 15, 2011). Retrieved November 29, 2011. Gottlob Espenlaub,Gottlob Espenlaub 1922 delta hang glider: . During the Wasserkuppe 1921 hang gliding competition, he met Alexander Lippisch and both engaged in collaboration on drafts and models of gliders and hanging gliders. Alexander Lippisch,Alexander Lippisch. Ctie.monash.edu.au. Retrieved November 29, 2011. Heinz Schneider, Francis Chardon,Francis Chardon . Objectifreussir.ch. Retrieved November 29, 2011. Willi Pelzner, and Hans RichterHans Richter. Britannica.com. Retrieved November 29, 2011. while engineer Henri Mignet was busy in France and was busy in Poland. Czesław Tański . Elknet.pl. Retrieved November 29, 2011.
Invention of the flexible wing In 1904 Jan Lavezzari demonstrated a stiffened flexible-wing hang glider in flight at Berck-sur-Mer, France. In 1908, a glider with a triangular control frame and the pilot tethered behind it was demonstrated in the territory of Breslau.Stephan Nitsch collection. Retrieved November 29, 2011. These two developments were not reported to aircraft designers, so they bore no influence on the later flexible wing developments.
In 1948, aeronautical engineer Francis Rogallo invented a self-inflating wing which he patented on March 20, 1951As an acknowledgement of his wife's enormous contribution to the project, Francis put the patent in her name.Rogallo's patents. Kitepatents.wordpress.com (June 27, 2006). Retrieved November 29, 2011. as the Flexible Wing,Diagrams of Rogallo's flexible wing. Fang-den-wind.de. Retrieved November 29, 2011. also known as the flexwing and Rogallo wing. Francis Rogallo had first proposed his flexible wing concept to the Langley Research Center in the late 1940s as a simple, inexpensive approach to recreational flying, but the idea was not accepted as a project.Rogallo wing proposed for recreational flying in the late 1940s . Nasa.gov (March 3, 2008). Retrieved November 29, 2011.
It was on October 4, 1957, when the Russian satellite Sputnik became a concern to the United States and marked the beginning of the 'space race' and the creation of NASA. Rogallo was in position to seize the opportunity and with his help at the wind tunnels, NASA began a series of experiments testing Rogallo's flexible wing, which got renamed Parawing, to evaluate it as a recovery system for the project Gemini space capsules.Also evaluated for recovery of used Saturn rocket stages: Space Flight Revolution Rogallo designed his flexible wing to allow the astronauts to deploy it like a parachute at subsonic speeds during reentry, then glide their capsule to a specified touchdown point.In 1965 Jack Swigert, who would later be one of the Apollo 13 astronauts, softly landed a full-scale Gemini capsule using a Parawing stiffened with inflatable tubes along the wing's edges F. Rogallo's team collaborated with at least two American aircraft companies, Ryan Aeronautical Company and North American Aviation, as there was potential for gliders, dirigible parachutes, and other new types of manned aircraft; this mainly involved stabilizing the leading edges with compressed air beams or rigid structures like aluminium tubes. By 1961 NASA had already made test flights of an experimental STOL aerial utility aircraft – the Ryan XV-8 (also known as the "Flying Jeep" or "Fleep")The earliest photographic press release of a Rogallo flexible wing in record dates to August 14, 1961, by Aviation Week and Space Technology magazine.Memoirs of a Ryan engineer on the Fleep: and by March 1962, of a weight-shift glider called Paresev.
Round parachutes were selected over the Rogallo wing to be used on the Gemini spacecraft and in 1965, funding on flexible wings research stopped.
Flexible-wing hang gliders
The simplicity of the Rogallo wing, ease of construction, capability of slow flight and its gentle landing characteristics did not go unnoticed by some hang glider and ultralight glider enthusiasts. The publicityPress release of the XV-8 'Fleep': August 14, 1961, by Aviation Week and Space Technology magazine. on the Fleep and the Paresev tests sparked interest in independent builders like Barry PalmerBarry Palmer's web site. Dated photos.. Video of his first flights in 1961 loaded in YouTube: and John Dickenson, who separately explored distinct airframes and control systems to be adapted to a Rogallo wing and be flown as a hang glider.
In August 1961, American engineer Barry Palmer developed and flew the first foot-launched Rogallo-wing hang glider.Several Langley employees shared Rogallo's enthusiasm for the innovative flight technology and even conducted manned flexible wing flight research during weekends on the Outer Banks with privately owned equipment. Although qualitative in nature, these investigations proved "valuable in providing quick answers and indicating promising directions for the much more costly and time consuming instrumented but unmanned NASA flight research." This took place near Latrobe, east of Sacramento, California. Palmer used aluminium tubing and no wires for construction, fearing kinking during assembly. Most flights were performed with just a set of inclined parallel bars that split his weight between his underarms and hands.
The last of Palmer's foot-launched hang gliders flew in the summer of 1962 and it had a ski-lift type of seat mounted to the keel with a universal joint for pendulum weight-shift control. During the period from 1961 to 1963 Barry Palmer made tens of flights using this concept. His longest flight ranged in length up to , at altitudes up to , and had an overall glide ratio of 4.5 to 1.