Paragliding
From Wikipedia, the free encyclopedia
Paragliding (known in France, Spain and Portugal as parapente) is a recreational and competitive flying sport. A paraglider is a free-flying, foot-launched aircraft. The pilot sits in a harness suspended below a fabric wing, whose shape is formed by the pressure of air
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[edit] Equipment
The paraglider wing (or ‘canopy’ or parafoil) is a self-inflating structure consisting of a row of cells,The pilot is supported underneath the wing from a web of lines (each with the strength to support the pilot). The lines are then attached to strap-like risers that are attached to the pilot's harness.
Controls held in the pilot’s hands, which pull down the trailing edge (rear portion) of the wing, are used to control speed and to turn.
The pilot is strapped into the bucket-seat harness, which usually holds a reserve parachute, and includes a ‘speed system’ which pulls down the leading edge for maximum flying speed. Modern recreational harnesses have a foam or air-bag back protector.
Paraglider wings typically have an area of 25–35 m² with a span of 8–12 m, and weigh 3–7 kg. Combined weight of wing, harness, reserve, instruments, helmet etc is around 12–18 kg.
Glide ratio ranges from 6:1 for recreational paragliders to about 10:1 for modern competition paragliders (compared with an average of 15:1 for hang gliders and up to 60:1 for some sailplanes), and speed range is typically 20–65 km/h (stall speed – max speed): though safe flying range is smaller.
Modern paraglider wings are made of high-performance non-porous fabrics such as Porcher Sport & Gelvenor, with Dyneema/Spectra or Kevlar/Aramid lines.
For storage and carrying, the wing is folded into the harness seat, and the whole stored in a backpack (which is normally stowed in the harness in flight).
Tandem paragliders, designed to carry the pilot and one passenger, are larger but otherwise similar. They usually have higher trim speeds (fly faster), are more resistant to collapses and have a slightly higher sink rate compared to solo paragliders.
Parachutes including skydiving canopies are generally used for descending purposes (i.e. jumping out of an aircraft or for dropping cargo) while paragliders are generally used for ascending. Paragliders are categorized as "ascending" parachutes by canopy manufacutures worldwide and involve "free flying" (without a tether) or an aircraft. However Paragliders can sometimes be tethered for a short period during towing to get airborne.
[edit] Flying
In unpowered flight, rising air is needed to keep a glider aloft. This rising air can come from two sources:
- when the sun heats features on the ground, columns of rising air known as thermals are generated
- when wind encounters a ridge in the landscape, the air is forced upwards, providing ridge lift.
In mountainous environments, flying is mostly based around thermals, which can be used to stay aloft before heading for a landing field below the launch site. In hill environments, ridge lift is used for ridge soaring, and landing can be done either back at the launch site, or at a landing field at the bottom of the ridge. In either case, more experienced pilots can use thermals to go ‘cross country’.
[edit] Ridge soaring
In ridge soaring, pilots fly along the length of a ridge feature in the landscape, relying on the lift provided by the air which is forced up as it passes over the ridge.
Ridge soaring is highly dependent on a steady wind within a defined range (the suitable range depends on the performance of the wing and the skill of the pilot). Too little wind, and insufficient lift is available to stay airborne (pilots end up ‘scratching’ along the slope). With more wind, gliders can fly well above and forward of the ridge, but too much wind, and there is a risk of being ‘blown back’ over the ridge.
When ridge soaring, it is usually possible to either ‘top land’ or ‘slope land’ close to the launch site, which saves time returning from a landing site back to the launch site.
[edit] Thermal flying
When the sun warms the ground, it will warm some features more than others (such as rock-faces or large buildings), and these set off thermals which rise through the air. Sometimes these may be a simple rising column of air; more often, they are blown sideways in the wind, and will break off from the source, with a new thermal forming later.
Once a pilot finds a thermal, he or she begins to fly in a circle, trying to center the circle on the strongest part of the thermal (the "core"), where the air is rising the fastest. Most pilots use a ‘vario’ (vario-altimeter), which indicates climb rate with beeps and/or a visual display, to help ‘core-in’ on a thermal.
Coring: The technique to "core" a thermal is simple: turn tighter as lift decreases, and turn less as lift increases. This ensures you are always flying around the core.
Often there is strong sink surrounding thermals, and there is often also strong turbulence resulting in wing collapses as a pilot tries to enter a strong thermal. Once inside a thermal, shear forces reduce somewhat and the lift tends to become smoother.
Good thermal flying is a skill which takes time to learn, but a good pilot can often "core" a thermal all the way to cloud base.
[edit] Cross-country flying
Once the skills of using thermals to gain altitude have been mastered, pilots can glide from one thermal to the next to go ‘cross-country’ (‘XC’). Having gained altitude in a thermal, a pilot glides down to the next available thermal. Potential thermals can be identified by land features which typically generate thermals, or by cumulus clouds which mark the top of a rising column of warm, humid air as it reaches the dew point and condenses to form a cloud. In many flying areas, cross-country pilots also need an intimate familiarity with air law, flying regulations, aviation maps indicating restricted airspace, etc.
[edit] Launching / landing
As with all aircraft, launching and landing are done into wind (though in mountain flying, it is possible to launch in nil wind and glide out to the first thermal).
In low winds, the wing is inflated with a ‘forward launch’, where the pilot runs forward so that the air pressure generated by the forward movement inflates the wing.
In higher winds, particularly ridge soaring, a ‘reverse launch’ is used, with the pilot facing the wing to bring it up into a flying position, then turning under the wing to complete the launch.
Reverse launches have a number of advantages over a forward launch. It is more straight forward to inspect the wing and check the lines are free as it leaves the ground. In the presence of wind, the pilot can be tugged toward the wing and facing the wing makes it easier to resist this force, and safer in case the pilot slips (as opposed to being dragged backwards). These launches are normally attempted with a reasonable wind speed making the ground speed required to pressurise the wing much lower - the pilot is initially launching while walking backwards as opposed to running forward.
In flatter countryside, pilots can also be launched with a tow. Once at full height, the pilot pulls a release cord and the towline falls away. This requires separate training, as flying on a winch has quite different characteristics from free flying. In many countries only towing from a stationary winch is permitted: ‘static’ towing, with a fixed length towline attached to a car, is far more dangerous.
Landing involves lining up for an approach into wind, and just before touching down, ‘flaring’ the wing to minimise forward speed. The angle of approach to the landing zone will depend on wind speed. Landing will typically be at a gentle forward run.
[edit] Control of the glider
The pilot holds controls in each hand which pull down the trailing edge of the wing. Pulling down the trailing edge increases the angle of attack of the wing from its ‘trim’ (hands-off) position, which slows it down and increases the lift generated (like flaps on an aircraft wing). Turning is achieved by a combination of pulling down the control on one side and ‘weight shift’ within the harness. Faster than ‘trim’ speed can be achieved by pushing out a ‘speedbar’ with the feet, which pulls down the leading edge to reduce the angle of attack.
On occasions when it is necessary to lose height more rapidly, the tips of the wing can be ‘folded in’, in what is known as ‘big ears’. This reduces the flying area of the wing, and increases the amount of drag, causing the glider to descend at a greater rate than in normal flight.
In more extreme conditions, other manoeuvres such as ‘b-line stalls’ and spiral dives can be used, but most pilots avoid getting themselves into situations where these are required.
[edit] Collapses
In turbulent air, since the wing is not rigid, part or all of the wing can collapse. On modern recreational wings, such collapses will normally recover themselves without pilot intervention. For the rare case where it is not possible to recover from a collapse (or from other threatening situations such as a spin), most pilots carry a reserve parachute. Thankfully, most pilots never have cause to ‘throw’ their reserve. In case the collapse happens near ground, i.e. shortly after takeoff or just before landing, the collapse may not recover even with pilot intervention and there will not be enough time for throwing the reserve. Those cases can result in serious injury or death. Collapses and other hazards are minimized by flying a suitable glider, and choosing appropriate locations and weather conditions, for the pilot's skill and experience.
[edit] Sports/competitive flying
Some pilots like to stretch themselves beyond recreational flying. For such pilots, there are multiple disciplines available:
- cross-country leagues – annual leagues of the greatest distance ‘XC’ flying
- ‘comps’ – competitive flying based around completing a number of tasks such as flying around set waypoints
- accuracy – spot landing competitions where pilots land on targets the size of jam-jar lids
- ‘acro’ – aero-acrobatic manoeuvres and stunt flying; heart stopping tricks such as helicopters, wing-overs, synchro spirals, infinity tumbles, and so on: see the Acromania site for some descriptions, also JustAcro.com and InAir.nlfor videos and photos of acro flying.
- national/international records – despite continually improving gliders, these become ever more difficult to achieve; aside from longest distance and highest altitude, examples include distance to declared goal, distance over triangular course, speed over 100 km triangular course, etc.
Competitive flying is done on high performance wings which demand far more skill to fly than their recreational counterparts, but which are far more responsive and offer greater feedback to the pilot, as well as flying faster with better glide ratios.
See also: FAI World Paragliding Championships, 2005 World Championship, Paragliding World Cup, Red Bull Vertigo Aerobatics World Cup, World Air Games.
[edit] Instruments
Most pilots use varios and radios when flying; some more advanced pilots also use GPS units.
[edit] Vario
Birds are highly sensitive to atmospheric pressure, and can tell when they are in rising or sinking air. People can sense the acceleration when they first hit a thermal, but cannot detect the difference between constant rising air and constant sinking air, so turn to technology to help.
A vario-altimeter indicates climb-rate (or sink-rate) with audio signals (beeps which increase in pitch and tempo as you accelerate upwards and a droning sound which gets deeper as your decent rate increases) and/or a visual display. It also shows altitude: either above takeoff, above sea level, or (at higher altitudes) ‘flight level’.
The main purpose of a vario 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.
[edit] Radio
Pilots use radio for training purposes, for communicating with other pilots in the air, particularly when travelling together on cross-country flights, and for reporting the location of landing.
Radios used are PTT (push-to-talk) transceivers, normally operating in or around the FM VHF 2-metre band (144–148 MHz) (Note that transmitting in the 144-148 MHz band requires a ham radio license.) 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] Safety
Paragliding is perhaps often viewed as a higher-risk sport than it actually is. Nonetheless, there is great potential for injury for the reckless or ill-prepared.
Most pilots will try to stay clear of:
- overly ‘active’ thermic conditions – harsh thermals can induce collapses in the wing, which require skill and experience to manage
- excessively windy conditions – landing can become dangerous, and if a glider is blown back behind a ridge where there is no longer rising air, it can encounter ‘rotor’, or turbulent air, which can collapse the wing – generally below the height at which a reserve parachute can be deployed
- cu-nimbs – cumulo-nimbus clouds are fed by massive thermals which rise faster than a paraglider can lose height, and can push a pilot deep into enormously turbulent, blind clouds
- hazardous landing conditions – in the lee of large trees or buildings there is ‘rotor’ which can collapse a wing; but among the greatest dangers are power lines
- reckless pilots – a danger to others, as well as themselves
Safety precautions include pre-flight checks, flying helmets, harnesses with back protection (foam or air-bag), a reserve parachute, and careful pre-launch observation of other pilots in the air to evaluate conditions.
For pilots who want to stretch themselves into more challenging conditions, advanced ‘SIV’ (simulation d’incidents de vol, or simulation of flying incidents) courses are available which teach pilots how to cope with hazardous situations which can arise in flight. Through tuition over radio (above a lake), pilots deliberately induce major collapses, stalls, spins, etc, in order to learn procedures for recovering from them. (As mentioned above, modern recreational wings will recover from minor collapses without intervention).
While fatalities and freak accidents do occur, most properly-trained, responsible pilots suffer nothing worse than possible minor injuries – particularly twisted ankles and back injuries – and an occasional pounding heart.
[edit] Learning to fly
Most popular paragliding regions have a number of schools, generally registered with and/or organized by national associations. Certification systems vary widely between countries, though around 10 days instruction to basic certification is standard.
There are several key components to a paragliding pilot certification instruction program. Initial training for beginning pilots usually begins with some amount of ground school to discuss the basics, including elementary theories of flight as well as basic structure and operation of the paraglider.
Students then learn how to control the glider on the ground, practicing take-offs and controlling the wing 'overhead'. Low, gentle hills are next where students get their first short flights, flying at very low altitudes, to get used to the handling of the wing over varied terrain. Special winches can be used to tow the glider to low altitude in areas that have no hills readily available.
As their skills progress, students move on to steeper/higher hills (or higher winch tows), making longer flights, and learning to turn the glider, control the glider's speed, then moving on to 360° turns, spot landings, ‘big ears’ (used to increase the rate of descent for the paraglider), and other more advanced techniques. Training instructions are often provided to the student via radio, particularly during the first flights.
A third key component to a complete paragliding instructional program provides substantial background in the key areas of meteorology, aerology, aviation law, and general flight area etiquette.
To give prospective pilots a chance to determine if they would like to proceed with a full pilot training program, most schools offer tandem flights, in which an experienced instructor pilots the paraglider with the prospective pilot as a passenger.
[edit] World records
The current (as of December 2006) world distance record of 426 km was set by two Slovenian brothers, Aljaz and Urban Valic, at De Aar, South Africa, on the 7th of December 2006. The Slovenian born Valic brothers travelled to South Africa in the middle of November 2006 with the specific goal to achieve a world record in terms of a declared goal. Despite tough and very strong conditions, and after spending 6 and half hours in the air, both brothers made the declared goal, and had enough height and time to continue to fly further, eventually landing within 300 meters of each other, setting a new world distance record of 426km. The two brothers flew at over 5200 meters above sea level.
The previous world distance record of 423 km was set by Will Gadd, Canada, on the 21st of June 2002. He tow-launched near Zapata, Texas, USA, and landed near Ozona, Texas just under 11 hours later. There is a story about the flight here.
The official world record for gain of height is held by Robbie Whittal, England, who gained 4526 m on January 6, 1993 in Brandvlei, South Africa.
On 14 February 2007, a German paraglider Ewa Wisnierska reached an altitude of 9947 m near Tamworth, Australia after being sucked up into a storm. She passed out due to a lack of oxygen and flew unconscious for up to an hour covered in ice, but managed to survive. [1]
Other records can be seen on the FAI site.
[edit] History
In 1954, the prescient Walter Neumark foresaw (in an article in Flight magazine) a time when a glider pilot would be “able to launch himself by running over the edge of a cliff or down a slope … whether on a rock-climbing holiday in Skye or ski-ing in the Alps”.
In 1961, the French engineer Pierre Lemoigne produced improved parachute designs which led to the Para-Commander (‘PC’), which had cut-outs at the rear and sides which enabled it to be towed into the air and steered – leading to parasailing/parascending.
Sometimes credited with the greatest development in parachutes since Leonardo da Vinci, the American Domina Jalbert invented in 1964 a rectangular parafoil which had sectioned cells in an aerofoil shape; an open leading edge and a closed trailing edge, inflated by passage through the air – the so-called ‘ram-air’ design.
Walter Neumark shortly afterwards wrote the wonderfully entitled Operating Procedures for Ascending Parachutes, and he and a group of enthusiasts with a passion for tow-launching ‘PCs’ and ram-air parachutes eventually broke away from the British Parachute Association to form the British Association of Parascending Clubs (BAPC) in 1973.
Meanwhile, David Barish was developing the ‘Sail Wing’ for recovery of NASA space capsules – “slope soaring was a way of testing out … the Sail Wing”. After tests on Hunter Mountain, New York in September 1965, he went on to promote ‘slope soaring’ as a summer activity for ski resorts (apparently without great success).
(NASA probably originated the term ‘paraglider’ in the early 1960’s, and ‘paragliding’ was first used in the early 1970’s to describe foot-launching of gliding parachutes).
These threads were pulled together in June 1978 by three friends Jean-Claude Bétemps, André Bohn and Gérard Bosson from Haute-Savoie, France. After inspiration from an article on ‘slope soaring’ in the Parachute Manual magazine by parachutist & publisher Dan Poynter, they calculated that on a suitable slope, a ‘square’ ram-air parachute could be inflated by running down the slope; Bétemps launched from Pointe du Pertuiset, Mieussy, and flew 100 m. Bohn followed him and glided down to the football pitch in the valley 1000 metres below. ‘Parapente’ (pente being French for slope) was born.
Through the 1980’s and since, it has been a story of constantly improving equipment and ever greater numbers of paragliding pilots. The first World Championship was held in Kössen, Austria in 1989.
[edit] Pilot numbers
Numbers of actively flying plots can only be a rough estimate, but France is believed to have the largest number, at around 25,000. Next most active flying countries are Germany, Austria, Switzerland, Japan, and Korea, at around 10,000 – 20,000, followed by Italy, the UK, and Spain with around 5,000 – 10,000. The USA has around 4,500. (All as of 2004).
[edit] Comparison with hang gliders
Paragliding and hang gliding are closely related sports: foot-launched gliders with flexible wings, with options for tow launching and for powered flight and there is sometimes confusion about the differences. Beyond sport definitions and sporting association class definitions, there is a perspective that simply treats paragliders as a proper subset of hang gliders (as an over class of aircraft apart from the influence of sporting classes).
The main differences between the two proper subsets of generalized hang gliders are:
| Paragliders | Hang gliders | |
|---|---|---|
| Wing structure: | entirely flexible, with shape maintained purely by the pressure of air flowing into the wing in flight and the tension of the lines | supported on a rigid frame which determines its shape and thus does not collapse in turbulence |
| Pilot position: | sitting ‘supine’ in a seated harness | usually lying ‘prone’ in a cocoon-like harness suspended from the wing. Seated, and 'supine' are also possible |
| Speed range (stall speed – max speed): | slower – hence easier to launch and fly in light winds, can get into trouble when winds pick up, poor wind penetration and no pitch control, cannot dive for speed | faster – much faster, up to 90+ mph, hence easier to launch and fly in stronger conditions with better wind penetration, and can out run bad weather, full pitch control |
| Glide angle: | poorer glide performance makes long-distances more difficult | better glide performance enables longer-distance flying, 430+ mile records |
| Landing-out: | smaller space needed to land, offering more landing options from cross-country flights. Also easier to carry back to the nearest road | longer approach & landing area required, but can reach more landing areas due superior glide range |
| Learning: | quicker to get ‘into the air’ with most skills learned in the air; flying tandem with an instructor is rarely necessary during instruction | basic control skills are learned in ground school, and in flights close to the ground prior to high flights; |
| Convenience: | pack smaller (easier to transport and store); lighter (easier to carry); quicker to rig & de-rig | more awkward to transport & store; longer to rig & de-rig |
| Cost: | cheaper but less durable | more expensive but more durable |
[edit] See also
- Powered paragliding
- Hang gliding
- Foot-launched Powered Hang Glider
- Gliding
[edit] References
Info & News
- TheFlyingEye.com Paragliding magazine
- Mac Para Australia Paragliding News from Australia
Discussions
- ParaglidingForum.com Largest Paragliding Forum
Sites
- paraglidingearth.com Site guide
- paragliding365.com Site guide in German language
Gliders
- P@r@2000 Paragliding world - Gérard Florit
- Paraglider Performance Comparison Jérôme Daoust
Safety
- Paragliding Safety Articles USHPA
- Tips for Paraglider Pilots Jérôme Daoust
- Paraglider survives being sucked into storm, ABC News Online
Competition
History
- Paragliding's "Believe it or not !" Jérôme Daoust
- Historical Review ParachuteHistory.com
- Para-Commander ParachuteHistory.com
- Domina Jalbert WindMuller Aerology Lab
- David Barish, The Forgotten Father of Paragliding FlyAboveAll
Online Videos
- Acro Paragliding Videos JustAcro
- Paragliding Videos InAir
- Paragliding Videos MyFlight Videos
- Paragliding and Powered Paragliding Videos Marks Paragliding Pages
- "Tree landing" an example of a paraglider helmet-cam video
- Paragliderpilot.tk Videos and photos.
- bkanal.ch: Vertigo Video Extreme Acro Videos from the Red Bull Vertigo, Montreux 2006
Photos
- Paragliding Photos Sport Paragliding
Humour
- Pie in the Sky Monthly Paragliding & Hang Gliding Satire
- Mort Mort Cartoons
- ParaLingo Paragliding Terminology
Paragliding Extrem
- Extrempilot Andi Siebenhofer English and German
[edit] External links
- Paragliding FAQs WikiFAQ
International and National Associations
- FAI International air sports federation
- FFVL French Federation of Free Flight
- HPAC Hang Gliding and Paragliding Association of Canada
- USHPA United States Hang gliding and Paragliding Association
- BHPA British Hang Gliding and Paragliding Association
- HGFA Hang Gliding Federation of Australia
- FPVL Portuguese Free Flight Federation
Paraglider Manufactures and Retailers
- Airwave Canada Paraglider Retailer
- Mac Para Australia Paraglider Retailer
Other
- HangGliderHistory Timeline, includes paragliders as a class of hang gliders
- Britain's Top Woman Paraglider Attacked by Wedge-tailed Eagles in Mid-Flight
- Champion paraglider survives storm that lifted her 32,000ft
