Hang gliding

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Hang gliding is an air sport. It is both recreational and competitive. Although it started out as simply gliding down small hills on low performance kites, hang gliding has evolved the ability to soar for hours with hawks and eagles, gain thousands of feet of altitude in thermal updrafts, and fly cross country over distances of hundreds of miles. The sport is closely related to paragliding and gliding (flying sailplanes) but using a much simpler and less expensive craft consisting of an aluminum- or composite-framed fabric wing, with the pilot mounted on a harness hanging from the wing frame and exercising control by shifting body weight.

Contents 1 Classes 2 History 3 Hang glider history 3.1 Hang Gliding Goes Global 3.2 History of Rigid Wing Hang Gliding 4 Training & Safety 5 Launch 6 Soaring Flight 6.1 Thermals 6.2 Ridge lift 6.3 Mountain wave 6.4 Convergence 7 Performance (2006) 8 Costs (2003) 9 Instruments 9.1 Vario 9.2 Radio 9.3 GPS 10 Records 11 Competition 12 Related sports 13 References 14 External links

[edit] Classes

In one perspective there are three classes of hang glider:

• The flexible wing hang glider, having flight controlled by a wing whose shape changes in virtue of the shifted weight of the pilot. This is not a paraglider.
• The rigid wing hang glider, having flight controlled by spoilers, typically on top of the wing. In both flexible and rigid wings the pilot hangs below the wing without any additional fairing.
• Class 2 (designated by the FAI as Sub-Class O-2) where the pilot is integrated into the wing by means of a fairing. These offer the best performance and are the most expensive.

All types of hang gliders can be foot-launched, but landing some class-2 hang gliders is only possible on wheels.

In another perspective there are more than three classes of hang glider. Consider a multi-plane rigid-winged hang glider that does not "shape change" in virtue of shifted pilot weight; Otto Lilienthal introduced this class of hang glider. Further, the rotary-wing hang gliders, though not popular, are in a class by themselves. Paragliders can be seen simply as one class of hang glider in alternative perspectives.

[edit] History

Main article: History of flexible wing hang gliding

[edit] Hang glider history

Many early glider designs copied from birds failed, the problem was that early flight pioneers often copied bird wings without understanding the underlying principles that made them work. The American historian Lynn White found two accounts indicating that a successful glider flight was made in the year 875 by a Moorish chemist and inventor named Abbas Ibn Firnas near Cordoba, Spain (Ibn Firnas crater on the Moon is named in his honor). It's possible that word of Ibn Firnas' flight was brought to England by returning Crusaders and to a Monk called Eilmer of Malmesbury^[2] who studied mathematics and astrology. A fellow Monk and historian -William of Malmesbury- reported years later that Eilmer flew off the roof of an Abbey in Malmsbury, England sometime between the years 1000 and 1010 gliding about 200 m (220 yards) and crashed breaking a leg.

A legend from the area of Slovakia tells of a Cyprian Monk called Kamadul, a generally educated remedial worker and botanist. He put together a hang glider and went to the highest peak in the region known as Tri Koruny, located just behind the Dunajec river on the Polish side. Legend has several versions though, one is that he was burned as a heretic, another said only the glider was burned and he was locked in the monastery for the rest of his days.

An exception probably was an illiterate Polish sculptor and carpenter Jan Wnęk, who built several wing models and, although he did not understand the aerodynamics of lift, he mimicked a bird's wing. He tested his weighted models by throwing them by hand. In 1866 he completed construction of an ash wood frame which he covered with linen impregnated with varnish. Jan Wnęk was firmly strapped to the glider by the chest and hips and controlled his glider by twisting the wing's trailing edge via strings attached to stirrups at his feet. Wnęk managed his first short controlled flights in June of that same year from a small hill. After several short flights, Wnęk felt confident enough to ask for authorization from the village church priest to build a special ramp on top of the church tower to launch from. The tower stood 45 m high and was located on top of a 50 m hill, making a 95 m (311 ft) high launch above the valley. Church records indicate that Jan Wnęk made several public flights between 1866 - 1869 especially during religious festivals, carnivals and New Year celebrations. His flying activities spanned about four years in time but Wnęk left no known written records or drawings, thus having no impact on aviation progress.

Starting in the 1880s advancements were made in construction that led to the first truly practical gliders and information was eagerly shared and published by early aviators and inventors such as John J. Montgomery, Gustave Whitehead, Louis Pierre Mouillard, George Cayley, Félix du Temple, Clément Ader, Francis Herbert Wenham, Gabriel Voisin, Wilhelm Kress, Louis Blériot, Alberto Santos Dumont, John Stringfellow, Jean-Marie Le Bris, Samuel Pierpont Langley, Hiram Maxim and Percy Pilcher ^[3]. But two designers in particular were systematically active: Otto Lilienthal and Octave Chanute.

Otto Lilienthal of Germany 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 ever-better gliders, and in 1891 was able to make flights of 25 meters or more routinely. He rigorously documented his work, influencing later designers; For this reason he is one of the best known of the early aviation pioneers. His type of aircraft is now known as a hang glider. By the time of his death in 1896 he had made about 2500 flights on a number of designs, when he crashed from a height of roughly 17 m (56 ft) fracturing his spine. Lilienthal had been working on small engines suitable for powering his designs at the time of his death.

Picking up where Lilienthal left off, Octave Chanute (North American) took up aircraft design after an early retirement, and funded the development of several gliders. In the summer of 1896 his team flew several of their designs many times at Miller Beach, Indiana, eventually deciding that the best was a biplane design that looks surprisingly modern.^[4] Like Lilienthal, he heavily documented his work while photographing it, and was busy corresponding with like-minded hobbyists around the world. Chanute was particularly interested in solving the problem of natural stability of the aircraft in flight. Although uncomfortable and only marginally controllable, variations of these plans have been continuously available since through a range of sources. It was mostly Wenham's wind tunnel and the documented work done by Otto Lilienthal and Octave Chanute that gave the Wright brothers the concepts needed to create their gliders and a number of sophisticated devices to measure lift and drag on the 200 wing designs they tested. As a result, the Wrights corrected earlier mistakes in calculations regarding drag and lift. On December 17, 1903 the Wright brothers flew a rudimentary airplane based on the design of their successful 1902 glider.

When the World War I ended in 1918, the Treaty of Versailles of 1919 was hard for the Germans. One of the consequences was that it practically ended their engine driven flights. 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 forces in the atmosphere to make them fly farther and faster, undergoing a "renaissance" of gliding aviation. The first German gliding competition was held at the Wasserkuppe^[5] in 1920. The best flight lasted two minutes and set a world distance record of 2 km. Within ten years, it had become an international event in which the achieved durations and distances had increased greatly. In 1931, Gunther Grönhoff flew a sailplane 272 km (169 miles) from Munich to Czechoslovakia, further than had been thought possible.^[6]

Since then, several people from many countries contributed to the evolution of gliders in their various forms^[7], for example: Alexander Schleicher, Willy Messerschmitt, Peter Riedel, Alexander Lippisch, Oscar Ursinus ^[8], Michael Schönherr ^[9], Carl S. Bates ^[10], Reinhold Platz ^[11], Willy Pelzner ^[12], Bob Trampenau ^[13], Robert Gomas, Dave Cronk ^[14], Taras Kiceniuk, Wolfgang Send ^[15], Patrick Lagrange, Yves Rousseau, Bob Wills ^[16], Jim Natland ^[17], Jeff Jobe, John James ^[18], Klaus Hill ^[19], Larry Hall ^[20], Eric Raymond ^[21], Miles Handley ^[22], Volmer Jensen ^[23], Dick Cheney ^[24], Klaus Bichlmeier, Dave Kilbourne ^[25], Hans Dämgen, P. Bicheron, R. Korobelnik, Etienne Rithner ^[26], Bob Rouse, Jack Lambie ^[27], Bob Lovejoy ^[28], Terry Sweeney, Tom Peghiny, Joe Faust ^[29], Dick Eipper and Richard Miller ^[30], to name a few.

The modern hang glider was greatly influenced by American engineer Francis Rogallo. In 1948 during his free time, he and his wife Gertrude Rogallo, invented and patented a self-inflating flexible kite ^[31] that they called the flexible wing.^[32] It was on October 4, 1957 when the Russian satellite Sputnik shocked the United States and the space race caught the imagination of its government, causing major increases in U.S. government spending on scientific research, education and on the immediate creation of NASA. Rogallo was in position to seize the opportunity and released their patent to the government and with his help at the wind tunnels, NASA began a series of experiments testing Rogallo's wing, which was dropped from altitudes as high as 200,000 feet and as fast as Mach 3 in order to evaluate it as a recovery system for the Gemini space capsules and recovery of used Saturn rocket stages.^[33][34] Francis Rogallo adapted and extended the totally flexible principle into semi-rigid variants. This mainly involved stabilizing the leading edges with compressed air beams or rigid structures like aluminum tubes. By 1960 NASA had already made test flights of a heavily framed cargo powered aircraft called the 'flying Jeep' or Fleep ^[35][36] and by March 12, 1962, pilot Milton O. Thompson first flew a weight shift glider called Parasev.^[37]

It is interesting to note that NASA was simultaneously testing other two deployable gliders for manned spacecraft recovery: Domina C. Jalbert's Parafoil ^[38] and David Barrish's Sail Wing. The Sail Wing was a narrow double-surface parachute based on the French engineer Pierre Lemoigne's stearable Para-Commander parachute conceived in 1961. The Sail Wing and Parafoil were eventually fused and developed into the paraglider by many creative minds from several countries.^[39] But by 1967 all Sail Wing, Parafoil and Para Wing projects were dropped by NASA in favor of using round parachutes without considering development of personal ultralight gliders. That task was taken by very few independent designers like Tony Prentice (English), Barry Palmer (North American), and especially: John Dickenson (Australian).

The simplicity of design and ease of construction of the Rogallo wing, along with its capability of slow flight, its gentle landing characteristics and unencumbered bird-like flight became available to almost anyone who wanted it, so when on August 1961 Barry Palmer saw a photo of the Fleep[32], he immediately completed construction and flew the first flexible wing hang glider; This took place near Latrobe, east of Sacramento, California.^[40] He used aluminum tubing and no wires for construction as he did fear kinking during assembly. Most flights were performed with just a set of inclined parallel bars that split his weight between his underarms and hands, but he demonstrated that the Para Wing could be controlled by shifting weight alone. The last of Palmer's craft flew in the summer of 1962 and it had a ski-lift type of seat mounted to the keel with a universal joint. A single control stick was projected down from the wing. During the period from 1961 to 1963 Barry Palmer made tens of flights using the Rogallo wing concept. Hisr longest flight ranged in length up to 180 meters (590 ft), at altitudes up to 24 meters (80 feet), and had an overall glide ratio of 4.5 to 1.^[41] Palmer's wing was heavy and not particularly portable. Palmer relates that he had a good paying aerospace job at the time and he was flying on a minimalist and inexpensive glider purely for fun and did not attempt to modernize or market the hang glider; As far as promotion, Palmer did not seek any and concealed his efforts to the American aviation bureaucracy (FAA) of flying without credentials in a pre-ultralight era, but freely gave information about the wing to any person interested.^[42] Palmer then moved on to design hovercrafts but the Palmer wing inspired Richard Miller to develop and fly the famous 'Bamboo Butterfly' hang glider, the plans of which circulated in some magazines in the mid 1960s.

Starting on 1960, Tony Prentice designed and flew several novel hang gliders in England, including an intriguing 'split wing'. ^[43] He built a number of non-Rogallo gliders which got progressively larger ^[44], the leading and trailing edges of the sail had preformed airfoil. There was no solid frame beneath the glider and the support was a rope beneath his underarms as this gave pendulum stability to the aircraft. Limited on budget, his designs were never developed further.

[edit] Hang Gliding Goes Global

A world wide hang glider revolution started on 1963 when Australian John Dickenson, a Grafton ‘Water Ski and Kite Flyers Association’ club member, set to build a portable and controllable manned kite he later called the Ski Wing. ^[45] An electrical engineer by profession, a big part of John's life revolved around televisions and their installation. He erected many television aerials, most of these were aluminum tubing with wire bracing. He understood this style of structure and knew in practical terms how strong triangular wire bracing was and the sorts of loads aluminum could take. Dickenson designed an incredibly smart and unique structure to fit on a Pawa Wing: The pilot sat comfortably on a swinging seat and a control frame became the 'fuselage', carrying the load and distributing that load to the wing as well as giving a frame to push against for control. The base bar carried tension stress during flight while the upright tubes were under a compression load. It also meant that the cross-bars operated under only a compression load, this is why the keel was able to be allowed to float, and why wing variable geometry (VG) for high glide performance became viable.

Dickenson's wing turned out to be stable and capable of producing lift, unlike the flat manned kites his friends were using at local water ski shows. Soon the wing was found to be more versatile: It could be released at altitude to glide back down to a landing. The kite turned out to be a controllable glider. Dickenson's wing was flown in public at the 'Grafton Jacaranda Festival' in September of 1963 by Rod Fuller while towed behind a motorboat. Australian water ski kite fliers introduced Dickenson's hang glider design to the rest of the world, stimulating a hang gliding boom in the 1970s.^[46][47] The Dickenson Wing's efficiency, simplicity and portability changed personal flight, and although by the early 1970s many rigid wings were developed, none sold terribly well and dozens of hang glider companies were springing up all over the world building thousands of Dickenson Wing copies. It was the total system –the combination of the light main airframe, control bar for bracing as well as control, the pendulum weight shift system, and all of that combined to make the foldable, portable package that dramatically reduced difficulty in storage, transport, assembly and repair. In addition, the flexible wing could always be redesigned to improve the performance far more easily than a rigid wing could be designed for portability.

It is certain that many people from many countries made very real contributions to the development of the modern hang glider, and in the aviation context of 'firsts flights' and recreational vs. commercial developments, it must be noted that new and old inventions often complement each, and it is in this evolutionary and social context that the crucial developments put together by John Dickenson were the ones that were most successful and influential.

[edit] History of Rigid Wing Hang Gliding

There have been several rigid wing hang gliders flown since Otto Lilienthal took his first flights in the 1890s, but two early and high performing hang gliders were the Mitchell Wing and the Icarus.

In the early 1940s Don Mitchell (Scotland), an aeronautical engineer, first became involved with flying wing glider design and construction. But WWII interrupted his research and experiments. Then in 1974, with the advent of hang glider mania, Mitchell's flying wing resurfaced. It was at that time Dr. Howard Long took an interest in the half-forgotten project and asked Don Mitchell to make him a flying wing hang glider. The result was the foot-launched Mitchell Wing. When the foot-launched Mitchell Wing B-10 flew in the 1977 USHGA Nationals, the hang gliding world was completely astounded. The Mitchell Wing then went on to set and hold every world record in its class. In 1980, George Worthington soared to 17,000 feet and then glided 105 miles, setting two new rigid-wing records. The Mitchell Wing had a single built-up "D" spar with aircraft birch plywood torsion proof leading edge and 3-axes control.^[48] Foam ribs placed every 4.5 inches hold the D shape. The built-up truss ribs aft of the spar are covered with fabric. This structural design is simple, extremely strong and light (under 80 Lbs).

On 1971 and 1972 the Icarus I and Icarus II were built, respectively.^[49] These were rigid biplane flying wing designs by Taras Kiceniuk, Jr. Icarus V was essentially a monoplane version of the previous Icarus designs. All of the hang gliders in the Icarus series had hand-controlled rudders and the pilot flew in a reclining position (rather than a prone position as with other hang gliders). Although many Icarus II and Icarus V gliders were built from plans sold by Kiceniuk, they were never commercially produced.

In the early 1990s, the Exxtacy (designer: Felix Ruehle) and then the IXBO became the first two rigid wing hang gliders on the market with a leading edge of carbon fiber. These were followed in 1999 by the ATOS (designer Felix Ruehle). The nose angle and wing span of modern rigid wings are a little larger and the sail is rather stiff.

[edit] Training & Safety

* Certified hang gliding schools in the USA: [33]

Hang gliding has traditionally been considered an unsafe sport, ever since its inception. Otto Lilienthal himself died of a fractured spine from a glider crash after a gliding career lasting only five years. Modern hang gliders are fairly sturdy when constructed by HGMA, BHPA or DHV*-certified manufacturers using modern materials, though they remain lightweight craft that can be easily damaged, either through misuse or by continued operation in unsafe wind/weather conditions. All modern gliders have built-in stall recovery mechanisms (such as luff lines in kingposted gliders) and are designed and tested for as much stability as possible, depending on the performance characteristics desired. Pilot safety is, as in all other forms of aviation, a matter of training (through certified instructors) and perhaps most importantly, self-discipline. Nevertheless, the inherent danger of gliding at the mercy of unpredictable thermal and wind currents, often in proximity to dangerous terrain, has resulted in numerous fatal accidents and many serious injuries over the years, even to experienced pilots, and the resultant adverse publicity has affected the popularity of hang gliding.

As a backup, pilots carry a parachute in the harness. In case of serious problems the parachute is deployed and carries both pilot and glider down to earth. Pilots also wear helmets and generally carry other safety items such as hook knives (for cutting their parachute bridle after impact or cutting their harness lines and straps in case of a tree or water landing), light ropes (for lowering from trees to haul up tools or climbing ropes), radios (for calling for help) and first aid equipment.

Another issue that has dramatically improved the safety of the modern hang glider pilot is training. Early hang glider pilots learned their sport through trial and error. Many of those errors have led to effective training techniques and programs developed for today's pilot, with emphasis on flight well within safe limits, as well as the discipline to cease flying when conditions are unfavorable.

[edit] Launch

Launch techniques include foot-launching from a hill, tow-launching from a ground-based tow system, aerotowing (behind a powered aircraft), and powered harnesses. Other, more exotic launch techniques have also been used successfully, such as hot air balloon drops for very high altitude. Flights in non-soarable conditions are referred to as "sled runs".

[edit] Soaring Flight

Glider pilots can stay airborne for hours. This is possible because they seek out rising air masses (lift) from the following sources:

[edit] Thermals

The most commonly used source of lift is created by the sun's energy heating the ground which in turn heats the air above it. This warm air rises in columns known as thermals. Soaring pilots quickly become aware of visual indications of thermals such as: cumulus clouds, cloud streets, dust devils and haze domes. Also, nearly every glider contains an instrument known as a variometer (a very sensitive vertical speed indicator) which shows visually (and often audibly) the presence of lift and sink. Having located a thermal, a glider pilot will circle within the area of rising air to gain height. In the case of a cloud street thermals can line up with the wind creating rows of thermals and sinking air. A pilot can use a cloud street to fly long straightline distances by remaining in the row of rising air.

[edit] Ridge lift

Another form of lift occurs when the wind meets a mountain, cliff or hill. The air is deflected up the windward face of the mountain forming lift. Gliders can climb in this rising air by flying along the feature. Another name for flying with ridge lift is slope soaring.

[edit] Mountain wave

The third main type of lift used by glider pilots are the lee waves that occur near mountains. The obstruction to the airflow can generate standing waves with alternating areas of lift and sink. The top of each wave peak is often marked by lenticular cloud formations.

[edit] Convergence

Another form of lift results from the convergence of air masses, as with a sea-breeze front.

More exotic forms of lift are the polar vortexes which the Perlan Project hopes to use to soar to great altitudes [34]. A rare phenomenon known as Morning Glory has also been used by glider pilots in Australia.^[50]

[edit] Performance (2006)

With each generation of materials and with the improvements in aerodynamics, the performance of hang gliders has increased. One measure of performance is the glide ratio. For example, a ratio of 12:1 means that in smooth air a glider can travel forward 12 meters while only losing 1 meter of altitude.

• Topless gliders: glide ratio ~17:1, speed range ~30 to >145 km/h, best glide at ~45 to 60 km/h
• Rigid wings: glide ratio ~20:1, speed range ~ 35 to > 130 km/h, best glide at ~50 to 60 km/h

Note: Glide ratio is typically not provided by the manufacturers as it is nearly impossible to measure reliably and because the pilot is in the airstream (unlike in a sailplane) depends on many factors like pilot weight, pilot position, harness design, helmet, placement of instruments and so on.

Balast The extra weight provided by ballast is advantageous if the lift is likely to be strong. Although heavier gliders have a slight disadvantage when climbing in rising air, they achieve a higher speed at any given glide angle. This is an advantage in strong conditions when the gliders spend only little time climbing in thermals.

[edit] Costs (2003)

• Rigid wings: ~10000 Euro
• Topless gliders: 5-6000 Euro
• Intermediates: ~4000 Euro
• Beginner gliders: < 3000 Euro
• Harness: 500 - 1500 Euro
• Parachute: ~ 500 Euro
• Instruments: 200 - 1000 Euro
• School: 2-3 lessons (introductory package) 3-400 Euro
• School: 10 lessons (full course) 800-1000 Euro

[edit] Instruments

In order to maximise a pilots understanding of how the hang glider is flying, most pilots carry a series of instruments. The most basic being a variometer and altimeter- often combined. Some more advanced pilots also carry airspeed indicators and radios. When flying in competition or "Cross country" pilots often also carry maps and/or GPS units. Hang gliders do not have instrument panels as such, so all the instruments are mounted to the control frame of the glider.

[edit] Vario

People can sense the acceleration when they first hit a thermal, but they cannot detect the difference between constant rising air and constant sinking air, so they turn to technology for help. A variometer is a very sensitive vertical speed indicator; in other words, indicates climb or sink rate with audio signals (beeps) and/or a visual display. These units are generally electronic, vary in sophistication and often include, an altimeter and airspeed indicator. More advanced units often incorporate a barograph for recording flight data and/or a built in GPS. The main purpose of a variometer is in helping a pilot find and stay in the ‘core’ of a thermal to maximise height gain, and conversely indicating when he or she is in sinking air, and needs to find rising air. Variometers are sometimes capable of electronic calculations based on the 'MacCready Ring' to indicate the optimal speed to fly for given conditions. The MacCready theory solves the problem of how fast a pilot should cruise between thermals, given both the average lift the pilot expects in the next thermal climb, as well as the amount of lift or sink he encounters in cruise mode. Some electronic variometers make the calculations automatically, after allowing for factors such as the glider's theoretical performance (glide ratio), altitude, hook in weight and wind direction.

[edit] Radio

Pilots use radio for training purposes, and for communicating with other pilots in the air – particularly when travelling together on cross-country flights.

Radios used are PTT (push-to-talk) transceivers, normally operating in or around the FM VHF 2-metre band (144–148 MHz). Usually a microphone is incorporated in the helmet, and the PTT switch is either fixed to the outside of the helmet, or strapped to a finger.

[edit] GPS

GPS (global positioning system) is a necessary accessory when flying competitions, where it has to be demonstrated that way-points have been correctly passed.

It can also be interesting to view a GPS track of a flight when back on the ground, to analyse flying technique. Computer software is available which allows various different analyses of GPS tracks (e.g. CompeGPS).

Other uses include being able 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.

More recently, the use of GPS data, linked to a computer, has enabled pilots to share 3D tracks of their flights on Google Earth. This fascinating insight allows comparisons between competing pilots to be made in a detailed 'post-flight' analysis.

[edit] Records

Records fall into nearly the same categories as those for sailplanes and are sanctioned by the FAI. The current world record(s) (as of 2005) for "free distance" is held by Manfred Ruhmer with 700.6 km (435.3 miles) in 2001, but Mike Barber has flown an uncertified distance of 704 km (437 miles) on June 19 2002 in Zapata Texas.

[edit] Competition

Competitions started with "flying as long as possible" and spot landings. With increasing performance cross-country flying replaced them. Usually two to four waypoints have to be passed with a landing at a goal. In the late 90s low-power GPS units were introduced and have completely replaced photographs of the goal. Every two years there is a world championship. The Rigid and Women's World Championship in 2006 was hosted by Quest Air in Florida. Big Spring, Texas is hosting the 2007 World Championship. Hang gliding is also one of the competition categories in World Air Games organized by Fédération Aéronautique Internationale (World Air Sports Federation - FAI). The FAI also has a chronology of the FAI World Hang Gliding Championships^[51]

[edit] Related sports

The related sports are gliding, in which the gliders have full control surfaces and an enclosed cockpit, and paragliding, where the pilot is sitting on a harness suspended below a fabric wing.

[edit] References

[edit] External links

• United States Hang Gliding and Paragliding Association - USHPA Official US Association
• Hang Gliding Org hang gliding forums and community, videos, pics, news.
• HangGliderHistory Timeline
• Hang glider bible
• Current hang gliding records
• DMOZ Open Directory category: Hang Gliding
• Hang Gliding Photo Gallery
• The Oz Report - Worldwide Hang Gliding eZine and blog
• Hang Gliding Photos
• Hang Gliding Faq
• HangGliderHistory group
• The Scottish Hang-gliding & Paragliding Federation
• The Longest Running Hang Gliding Competition in the World
• Info about Hang Gliding
• The British Hang Gliding and Paragliding association