Parachuting

 

Parachuting, or skydiving, is a method of exiting an aircraft and returning to Earth with the aid of gravity, then slowing down during the last part of the descent by using a parachute. It may or may not involve a certain amount of free-fall, a time during which the parachute has not been deployed and the body gradually accelerates to terminal velocity.

Andre-Jacques Garnerin was the first to make successful descents using a canvas canopy and small basket, tethered beneath a hot-air balloon. The first intentional freefall jump with a ripcord-operated deployment is credited to Leslie Irvin in 1919.

The military developed parachuting technology as a way to save aircrews from emergencies aboard balloons and aircraft in flight, and later as a way of delivering soldiers to the battlefield. Early competitions date back to the 1930s, and it became an international sport in 1952.

Common Uses

Parachuting is performed as a recreational activity, a competitive sport, and is widely considered an extreme sport due to the risk involved. Modern militaries utilize parachuting for the deployment of airborne forces, and special operations forces commonly employ parachuting, especially free-fall parachuting, as a method of insertion. Occasionally forest firefighters, known as "smokejumpers" in the United States of America, use parachuting as a means of rapidly inserting themselves near forest fires in especially remote or otherwise inaccessible areas.

Manually exiting an aircraft and parachuting to safety has been widely used by aviators (especially military aviators), aircrew, and passengers to escape an aircraft that could not otherwise land safely. While this method of escape is relatively rare in modern times, it was commonly used in World War I by military aviators, and utilized extensively throughout World War II. In modern times, the most common means of escape from an aircraft in distress is via an ejection seat system. Said system is usually operated by the pilot, aircrew member, or passenger, by engaging an activation device manually. In most designs, this will lead to the seat being propelled out of and away from the aircraft carrying the occupant with it, by means of either an explosive charge or a rocket propulsion system. Once clear of the aircraft, the ejection seat will deploy a parachute, although some older models entrusted this step to manual activation by the seat's occupant.
Safety

Despite the perception of danger, fatalities are rare. About 21 skydivers are confirmed killed each year in the US, roughly one death for every 150,000 jumps (about 0.0007%).
In the US and in most of the western world skydivers are required to carry two parachutes. The reserve parachute must be periodically inspected and re-packed (whether used or not) by a certificated parachute rigger (in the US, an FAA certificated parachute rigger). Many skydivers use an automatic activation device (AAD) that opens the reserve parachute at a pre-determined altitude if it detects that the skydiver is still in free fall. Depending on the country, AADs are often mandatory for new jumpers, and/or required for all jumpers regardless of their experience level. Most skydivers wear a visual altimeter, and an increasing number also use audible altimeters fitted to their helmet.

Injuries and fatalities occurring under a fully functional parachute usually happen because the skydiver performed unsafe maneuvers or made an error in judgment while flying their canopy, typically resulting in a high speed impact with the ground or other hazards on the ground. One of the most common sources of injury is a low turn under a high-performance canopy and while swooping. Swooping is the advanced discipline of gliding at high speed parallel to the ground during landing.

Changing wind conditions are another risk factor. In conditions of strong winds, and turbulence during hot days the parachutist can be caught in downdrafts close to the ground. Shifting winds can cause a crosswind or downwind landing which have a higher potential for injury due to the wind speed adding to the landing speed.

Another risk factor is that of "canopy collisions", or collisions between two or more skydivers under fully inflated parachutes. Canopy collisions can cause the jumpers' inflated parachutes to entangle with each other, often resulting in a sudden collapse (deflation) of one or more of the involved parachutes. When this occurs, the jumpers often must quickly perform emergency procedures (if there is sufficient altitude to do so) to "cut-away" (jettison) from their main canopies and deploy their reserve canopies. Canopy collisions are particularly dangerous when occurring at altitudes too low to allow the jumpers adequate time to safely jettison their main parachutes and fully deploy their reserve parachutes.

Equipment failure rarely causes fatalities and injuries. Approximately one in 750 deployments of a main parachute result in a malfunction. Ram-air parachutes typically spin uncontrollably when malfunctioning, and must be jettisoned before deploying the reserve parachute. Reserve parachutes are packed and deployed differently; they are also designed more conservatively and built and tested to more exacting standards so they are more reliable than main parachutes, but the real safety advantage comes from the probability of an unlikely main malfunction multiplied by the even less likely probability of a reserve malfunction. This yields an even smaller probability of a double malfunction although the possibility of a main malfunction that cannot be cutaway causing a reserve malfunction is a very real risk.

Parachuting disciplines such as BASE jumping or those that involve equipment such as wing suit flying and sky surfing have a higher risk factor due to the lower mobility of the jumper and the greater risk of entanglement. For this reason these disciplines are generally practiced by experienced jumpers.

Depictions in commercial films – notably Hollywood action movies – usually overstate the dangers of the sport. Often, the characters in such films are shown performing feats that are physically impossible without special effects assistance. In other cases, their practices would cause them to be grounded or shunned at any safety-conscious drop zone or club. USPA member drop zones in the US and Canada are required to have an experienced jumper act as a "safety officer" (in Canada DSO – Drop Zone Safety Officer; in the U.S. S&TA – Safety and Training Advisor) who is responsible for dealing with jumpers who violate rules, regulations, or otherwise act in a fashion deemed unsafe by the appointed individual.

In many countries, either the local regulations or the liability-conscious prudence of the drop zone owners require that parachutists must have attained the age of majority before engaging in the sport.

BASE jumping

 

BASE jumping, also sometimes written as B.A.S.E. jumping, is parachuting or wingsuit flying from a fixed structure or cliff. "BASE" is an acronym that stands for four categories of fixed objects from which one can jump: building, antenna, span, and Earth (cliff). Due to the lower altitudes of the jumps, BASE jumping is significantly more dangerous than skydiving from a plane. In the U.S., BASE jumping is currently regarded by many as a fringe extreme sport or stunt. In some jurisdictions or locations, BASE jumping is prohibited or illegal; in some places, however, it is permitted. BASE jumping became known to the wider public by depictions of BASE jumping in a number of action movies.
History

The acronym "B.A.S.E." (now more commonly "BASE") was coined by filmmaker Carl Boenish, his wife Jean Boenish, Phil Smith, and Phil Mayfield. Carl Boenish was the catalyst behind modern BASE jumping, and in 1978, he filmed the first BASE jumps to be made using ram-air parachutes and the freefall tracking technique (from El Capitan, in Yosemite National Park). While BASE jumps had been made prior to that time, the El Capitan activity was the effective birth of what is now called BASE jumping.

BASE numbers are awarded to those who have made at least one jump from each of the four categories (buildings, antennas, spans and earth). When Phil Smith and Phil Mayfield jumped together from a Houston skyscraper on 18 January 1981, they became the first to attain the exclusive BASE numbers (BASE #1 and #2, respectively), having already jumped from an antenna, spans, and earthen objects. Jean and Carl Boenish qualified for BASE numbers 3 and 4 soon after. A separate "award" was soon enacted for Night BASE jumping when Mayfield completed each category at night, becoming Night BASE #1, with Smith qualifying a few weeks later.

Faust Vrancic is widely believed to have performed a parachute jumping experiment for real and, therefore, to be the first man to build and test a parachute: according to the story passed on, Veranzio, in 1617, then over sixty-five years old, implemented his design and tested the parachute by jumping from St Mark's Campanile in Venice. It is generally added that this event were documented some 30 years later in a book Mathematical Magick or, the Wonders that may be Performed by Mechanical Geometry (London, 1648) written by John Wilkins, the secretary of the Royal Society in London.

However, these and other sporadic incidents were one-time experiments, not the systematic pursuit of a new form of parachuting. After 1978, the filmed jumps from El Capitan were repeated, not as a publicity exercise or as a movie stunt, but as a true recreational activity. It was this that popularised BASE jumping more widely among parachutists. Carl Boenish continued to publish films and informational magazines on BASE jumping until his death in 1984 after a BASE-jump off of the Troll Wall. By this time, the concept had spread among skydivers worldwide, with hundreds of participants making fixed-object jumps.

During the early eighties, nearly all BASE jumps were made using standard skydiving equipment, including two parachutes (main and reserve), and deployment components. Later on, specialized equipment and techniques were developed specifically for the unique needs of BASE jumping.

Upon completing a jump from all of the four object categories, a jumper may choose to apply for a "BASE number", which are awarded sequentially. BASE #1 was awarded to Phil Smith of Houston, Texas in 1981. The 1000th application for a BASE number was filed in March 2005 and BASE #1000 was awarded to Matt "Harley" Moilanen of Grand Rapids, Michigan. As of December 2014, over 1,850 BASE numbers have been issued.

BASE jumping is often featured in action movies. The 2002 Vin Diesel film xXx includes a scene where Diesel's character catapults himself off the Foresthill Bridge in an open-topped car, landing safely as the car crashes on the ground. In the movie Lara Croft Tomb Raider: The Cradle of Life, includes the scene in which the main characters jump with wing suits from the IFC Tower in Hong Kong and fly over the Bank of China, finally opening their parachutes to land on a moving freighter. The stunt was done live, with no special effects, by base jumpers Martin Rosén and Per Eriksson, members of the Swedish "Team Bautasten". The scene was filmed by air-to-air camera man Mikael Nordqvist from the same team. Since the 1976 Mount Asgard jump featured in the pre-credits sequence to The Spy Who Loved Me, James Bond movies have featured several BASE jumps, including one from the Eiffel Tower in 1985's A View to a Kill, the Rock of Gibraltar in 1987's The Living Daylights, and in Die Another Day, 2002, Pierce Brosnan as James Bond jumps from a melting iceberg. Of the James Bond jumps only the Mt Asgard and Eiffel Tower jumps were filmed live; the rest were special effects. And in 2005's "Batman Begins", Bruce Wayne uses BASE jumping as inspiration for his memory cloth cape. A series of BASE jumps are featured in the video for a remix of M83's "Lower Your Eyelids to Die With the Sun".

Guinness World Records first listed a BASE jumping record with Carl Boenish's 1984 leap from Trollveggen (Troll Wall) in Norway. It was described as the highest BASE jump. (The jump was made two days before Boenish's death at the same site.) This record category is still in the Guinness book and is currently held by Australians Glenn Singleman and Heather Swan with a jump from Meru Peak in northern India at a starting elevation of 6,604 metres (21,667 ft). On July 8, 2006 Captain Daniel G. Schilling set the Guinness World Record for the most BASE jumps in a twenty-four hour period. Schilling jumped off the Perrine Bridge in Twin Falls, Idaho a record 201 times.

BASE competitions have been held since the early 1980s, with accurate landings or free fall aerobatics used as the judging criteria. Recent years have seen a formal competition held at the 452 metres (1,483 ft) high Petronas Towers in Kuala Lumpur, Malaysia, judged on landing accuracy.
In 2010 North west Norway celebrated with a world record with 53 Base jumpers jumping from a cliff.

Ice climbing

Ice climbing is the activity of ascending inclined ice formations. Usually, ice climbing refers to roped and protected climbing of features such as icefalls, frozen waterfalls, and cliffs and rock slabs covered with ice refrozen from flows of water. For the purposes of climbing, ice can be broadly divided into two spheres, alpine ice and water ice. Alpine ice is found in a mountain environment, usually requires an approach to reach, and is often climbed in an attempt to summit a mountain. Water ice is usually found on a cliff or other outcropping beneath water flows. Alpine ice is frozen precipitation whereas water ice is a frozen liquid flow of water. Most alpine ice is generally one component of a longer route and often less technical, having more in common with standard glacier travel, while water ice is selected largely for its technical challenge. Technical grade is, however, independent of ice type and both types of ice vary greatly in consistency according to weather conditions. Ice can be soft, hard, brittle or tough. Mixed climbing is ascent involving both ice climbing and rock climbing.

Techniques
A climber chooses equipment according to the slope and texture of the ice. For example, on flat ice, almost any good hiking or mountaineering boot will usually suffice, but for serious ice climbing double plastic mountaineering boots or their stiff leather equivalent are usually used, which must be crampon compatible and stiff enough to support the climber and maintain ankle support. On short, low angled slopes, one can use an ice axe to chop steps. For longer and steeper slopes or glacier travel, crampons are mandatory for a safe climb. Vertical ice climbing is done with crampons and ice axes (those specific to vertical ice generally being called technical ice axes, or ice tools); climbers kick their legs to engage the front points of the crampons in the ice, and then swing the axe into the ice above their heads. This technique is known as front pointing. The strength of the ice is often surprising; even if the axe goes in only a centimeter or so it is enough to pull up on. If a climber is leading, they will need to place ice screws as protection on the way up (see climbing system). Most mountaineers would only consider the last scenario true ice climbing; the less steep variations are routine aspects of winter mountaineering.

Some important techniques and practices common in rock climbing that are employed in ice climbing include knowledge of rope systems, tying in, belaying, leading, abseiling, and lowering. Beginners should learn these techniques before attempting to ice climb. It is highly recommended that one acquire knowledge from experts and experienced ice climbers.

Rope systems
Single, double, and twin rope are the three main rope systems used in ice climbing. The single rope system, which is suited for straight climbing routes, is the most commonly used rock climbing system in the world. Also often used in climbing is the double rope system which is a more flexible system than the single rope system. Lastly, the twin rope system, which uses two twin ropes in a single rope system, is used for longer multi-pitch routes. Double and twin rope technique is used more frequently in ice climbing because these systems are more redundant, an important consideration given the number of sharp edges the ice climber carries with him. Impact force on ice is an issue, with double ropes gaining popularity over twins.

Tying in
Tying in entails attaching your rope to the climbing harness. This technique is a must particularly when leading a climb or belaying. A commonly used tie-in knot is the Figure-of-eight follow through, but the Bowline and Thumb (stopper) knot is often preferred, since it is easier to untie when frozen. This technique should be done properly to ensure your safety when ice climbing.

Kitesurfing

Kiteboarding is a surface water sport combining aspects of wakeboarding, windsurfing, surfing, paragliding, and gymnastics into one extreme sport. A kiteboarder harnesses the power of the wind with a large controllable power kite to be propelled across the water on a kiteboard similar to a wakeboard or a small surfboard, with or without footstraps or bindings.

Kitesurfing is a style of kiteboarding specific to wave riding, which utilizes standard surfboards or boards shaped specifically for the purpose.

There are different styles of kiteboarding, including freestyle, freeride, downwinders, speed, course racing, wakestyle, jumping and kitesurfing in the waves. In 2012, the number of kitesurfers was estimated by the ISAF and IKA at 1.5 million persons worldwide  (pending review). The global market for kite gear sales is worth US$321 million.

History

In the 1800s, George Pocock used kites of increased size to propel carts on land and ships on the water, using a four-line control system—the same system in common use today. Both carts and boats were able to turn and sail upwind. The kites could be flown for sustained periods. The intention was to establish kitepower as an alternative to horsepower, partly to avoid the hated "horse tax" that was levied at that time. In 1903, aviation pioneer Samuel Cody developed "man-lifting kites" and succeeded in crossing the English Channel in a small collapsible canvas boat powered by a kite

In the late 1970s, the development of Kevlar then Spectra flying lines and more controllable kites with improved efficiency contributed to practical kite traction. In 1978, Ian Day's "FlexiFoil" kite-powered Tornado catamaran exceeded 40 km/h.

In October 1977 Gijsbertus Adrianus Panhuise (Netherlands) received the first patent for KiteSurfing. The patent covers, specifically, a water sport using a floating board of a surf board type where a pilot standing up on it is pulled by a wind catching device of a parachute type tied to his harness on a trapeze type belt. Although this patent did not result in any commercial interest, Gijsbertus Adrianus Panhuise could be considered as the originator of KiteSurfing.

Through the 1980s, there were occasionally successful attempts to combine kites with canoes, ice skates, snow skis, water skis and roller skates.

Throughout the 1970s and early 1980s, Dieter Strasilla from Germany developed parachute-skiing and later perfected a kiteskiing system using self made paragliders and a ball-socket swivel allowing the pilot to sail upwind and uphill but also to take off into the air at will. Strasilla and his Swiss friend Andrea Kuhn used this invention also in combination with surfboards and snowboards, grasskies and selfmade buggies. One of his patents describes in 1979 the first use of an inflatable kite design for kitesurfing.

Two brothers, Bruno Legaignoux and Dominique Legaignoux, from the Atlantic coast of France, developed kites for kitesurfing in the late 1970s and early 1980s and patented an inflatable kite design in November 1984, a design that has been used by companies to develop their own products.

In 1990, practical kite buggying was pioneered by Peter Lynn at Argyle Park in Ashburton, New Zealand. Lynn coupled a three-wheeled buggy with a forerunner of the modern parafoil kite. Kite buggying proved to be very popular worldwide, with over 14,000 buggies sold up to 1999.

The development of modern day kitesurfing by the Roeselers in the USA and the Legaignoux in France carried on in parallel to buggying. Bill Roeseler, a Boeing aerodynamicist, and his son Cory Roeseler patented the "KiteSki" system which consisted of water skis powered by a two line delta style kite controlled via a bar mounted combined winch/brake. The KiteSki was commercially available in 1994. The kite had a rudimentary water launch capability and could go upwind. In 1995, Cory Roeseler visited Peter Lynn at New Zealand's Lake Clearwater in the Ashburton Alpine Lakes area, demonstrating speed, balance and upwind angle on his 'ski'. In the late 1990s, Cory's ski evolved to a single board similar to a surfboard.

In 1996, Laird Hamilton and Manu Bertin were instrumental in demonstrating and popularising kitesurfing off the Hawaiian coast of Maui while in Florida Raphaël Baruch experimented riding windsurfing boards with various foil kites and changing the name of the sport from flysurfing to kitesurfing.

In 1997, the Legaignoux brothers developed and sold the breakthrough "Wipika" kite design which had a structure of preformed inflatable tubes and a simple bridle system to the wingtips, both of which greatly assisted water re-launch. Bruno Legaignoux has continued to improve kite designs, including developing the bow kite design, which has been licensed to many kite manufacturers. In 1997, specialized kite boards were developed by Raphaël Salles and Laurent Ness. By the end of 1998 kitesurfing had become an extreme sport, distributed and taught through a handful group of shops and schools worldwide. The first competition was held on Maui in September 1998 and won by Flash Austin.

Starting in 1999, kitesurfing became a mainstream sport with the entry of key windsurfing manufacturers namely Naish and Neil Pryde. Single direction boards derived from windsurfing and surfing designs became the dominant form of kiteboard. From 2001 onwards, twin-tip bi-directional boards became more popular for most flat water riders, with directional boards still in use for surf conditions.

In May 2012, the course racing style of kitesurfing was announced as a sport for the 2016 Rio Olympics, replacing windsurfing. However, after a vote by the General Assembly of ISAF in November 2012 (in Dun Laoghaire, Ireland) the RSX windsurfer was reinstated for both Men and Women this was an unprecedented decision when the constituent members of ISAF overthrew a decision made by the ISAF Council  Kitesurfing remains therefore a non-Olympic sport until 2020 at the earliest. The ISAF mid-year meeting of May 2013 proposed seeking an eleventh medal to include kitesurfing in 2020  at the same time there was a commitment made to retain the existing other 10 classes as they are for 2020 and even 2024 including the RSX windsurfer for men and women.

Kitesurfing is soon to be named as an official event at the 2018 Youth Olympics in Buenos Aires.

Speed records

French kitesurfer Sébastien Cattelan became the first sailor to break the 50 knots barrier by reaching 50.26 knots on 3 October 2008 at the Lüderitz Speed Challenge in Namibia. On 4 October, Alex Caizergues (also of France) broke this record with a 50.57 knots run. Similar speeds are reached by windsurfers in the same location by Anders Bringdal and Antoine Albeau, respectively 50.46 and 50.59 knots. These speeds are verified, but are still subject to ratification by the World Sailing Speed Record Council. Earlier in the event, on 19 September, American Rob Douglas reached 49.84 knots (92.30 km/h), becoming the first kitesurfer to establish an outright world record in speed sailing. Previously the record was held only by sailboats or windsurfers. Douglas also became the world's third over-50 knots sailor, when on 8 September he made a 50.54 knots (93.60 km/h) run.

On the 14th of November 2009, Alex Caizergues completed another run of 50.98 knots in Namibia.

October 2010, Rob Douglas became the outright record holder for the short distance 500 meters with 55.65 knots. Sébastien Cattelan became the record holder of France and Europe with 55.49 and was the first rider to reach 55 knots.

Paragliding

Paragliding is the recreational and competitive adventure sport of flying paragliders: lightweight, free-flying, foot-launched glider aircraft with no rigid primary structure. The pilot sits in a harness suspended below a fabric wing comprising a large number of interconnected baffled cells. Wing shape is maintained by the suspension lines, the pressure of air entering vents in the front of the wing, and the aerodynamic forces of the air flowing over the outside.

Despite not using an engine, paragliders flight can last many hours and cover many hundreds of kilometers, though flights of one to two hours and covering some tens of kilometers are more the norm. By skilful exploitation of sources of lift, the pilot may gain height, often climbing to altitudes of a few thousand meters.
Related activities

Paragliding is related to the following activities: Hang gliding is a close cousin, and hang-glider and paraglider launches are often found in proximity to one another. Despite the considerable difference in equipment, the two activities offer similar pleasures, and some pilots are involved in both sports.

Powered paragliding is the flying of paragliders with a small engine attached. Speed riding, or speed flying, is the separate sport of flying paragliders of a reduced size. These wings have increased speed, though they are not normally capable of soaring flight. The sport involves taking off on skis or on foot and swooping rapidly down in close proximity to a slope, even periodically touching it if skis are used. These smaller wings are also sometimes used where wind speeds are too high for a full-sized paraglider, although this is invariably at coastal sites where the wind is laminar and not subject to as much mechanical turbulence as inland sites.
Takeoff from a ramp, Tegelberg, Schwangau, Germany
Tandem Paragliding at Solang Valley, Manali, Himachal Pradesh, India
Paragliding over Jounieh Bay, Lebanon

Paragliding can be of local importance as a commercial activity. Paid accompanied tandem flights are available in many mountainous regions, both in the winter and in the summer. In addition, there are many schools offering courses and guides who lead groups of more experienced pilots exploring an area. Finally, there are the manufacturers and the associated repair and after-sales services. Paraglider-like wings also find other uses, for example, in ship propulsion and wind energy exploitation, and are related to some forms of power kite. Kite skiing uses equipment similar to paragliding sails.

Equipment
Wing

The paraglider wing or canopy is usually what is known in aeronautical engineering as a "ram-air airfoil". Such wings comprise two layers of fabric that are connected to internal supporting material in such a way as to form a row of cells. By leaving most of the cells open only at the leading edge, incoming air keeps the wing inflated, thus maintaining its shape. When inflated, the wing's cross-section has the typical teardrop aerofoil shape. Modern paraglider wings are made of high-performance non-porous materials such as ripstop polyester or nylon fabric.
In some modern paragliders (from the 1990s onwards), especially higher-performance wings, some of the cells of the leading edge are closed to form a cleaner aerodynamic profile. Holes in the internal ribs allow a free flow of air from the open cells to these closed cells to inflate them, and also to the wingtips, which are also closed.
The pilot is supported underneath the wing by a network of suspension lines. These start with two sets of risers made of short (40 cm) lengths of strong webbing. Each set is attached to the harness by a carabiner, one on each side of the pilot, and each riser of a set is generally attached to lines from only one row of its side of wing. At the end of each riser of the set, there is a small delta maillon with a number (2-5) of lines attached, forming a fan. These are typically 4–5 metres long, with the end attached to 2−4 further lines of around 2 m, which are again joined to a group of smaller, thinner lines. In some cases this is repeated for a fourth cascade.

The top of each line is attached to small fabric loops sewn into the structure of the wing, which are generally arranged in rows running span-wise (i.e., side to side). The row of lines nearest the front are known as the A lines, the next row back the B lines, and so on.[18] A typical wing will have A, B, C and D lines, but recently, there has been a tendency to reduce the rows of lines to three, or even two (and experimentally to one), to reduce drag.

Paraglider lines are usually made from Dyneema/Spectra or Kevlar/Aramid.[18] Although they look rather slender, these materials are immensely strong. For example, a single 0.66 mm-diameter line (about the thinnest used) can have a breaking strength of 56 kg.
Paraglider wings typically have an area of 20–35 square metres (220–380 sq ft) with a span of 8–12 metres (26–39 ft) and weigh 3–7 kilograms (6.6–15.4 lb). Combined weight of wing, harness, reserve, instruments, helmet, etc. is around 12–22 kilograms (26–49 lb).

The glide ratio of paragliders ranges from 9.3 for recreational wings to about 11.3 for modern competition models, reaching in some cases up to 13.[21] For comparison, a typical skydiving parachute will achieve about 3:1 glide. A hang glider ranges from 9.5 for recreational wings to about 16.5 for modern competition models. An idling (gliding) Cessna 152 light aircraft will achieve 9:1. Some sailplanes can achieve a glide ratio of up to 72:1.

The speed range of paragliders is typically 20–75 kilometres per hour (12–47 mph), from stall speed to maximum speed. Beginner wings will be in the lower part of this range, high-performance wings in the upper part of the range.
For storage and carrying, the wing is usually folded into a stuffsack (bag), which can then be stowed in a large backpack along with the harness. For pilots who may not want the added weight or fuss of a backpack, some modern harnesses include the ability to turn the harness inside out such that it becomes a backpack.

Paragliders are unique among human-carrying aircraft in being easily portable. The complete equipment packs into a rucksack and can be carried easily on the pilot's back, in a car, or on public transport. In comparison with other air sports, this substantially simplifies travel to a suitable takeoff spot, the selection of a landing place and return travel.

Tandem paragliders, designed to carry the pilot and one passenger, are larger but otherwise similar. They usually fly faster with higher trim speeds, are more resistant to collapse, and have a slightly higher sink rate compared to solo paragliders.
Harness
A pilot with harness (light blue), performing a reverse launch

The pilot is loosely and comfortably buckled into a harness, which offers support in both the standing and sitting positions. Most harnesses have foam or airbag protectors underneath the seat and behind the back to reduce the impact on failed launches or landings. Modern harnesses are designed to be as comfortable as a lounge chair in the sitting position. Many harnesses even have an adjustable "lumbar support". A reserve parachute is also typically connected to a paragliding harness.

Instruments

Most pilots use variometers, radios, and, increasingly, GPS units when flying.

Variometer

Main article: Variometer

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, to indicate when a pilot is in sinking air and needs to find rising air. Humans can sense the acceleration when they first hit a thermal, but cannot detect the difference between constant rising air and constant sinking air. Modern variometers are capable of detecting rates of climb or sink of 1 cm per second. A variometer indicates climb rate (or sink-rate) with short audio signals (beeps, which increase in pitch and tempo during ascent, and a droning sound, which gets deeper as the rate of descent increases) and/or a visual display. It also shows altitude: either above takeoff, above sea level, or (at higher altitudes) flight level.

Radio

Radio communications are used in training, to communicate with other pilots, and to report where and when they intend to land. These radios normally operate on a range of frequencies in different countries—some authorised,[22][23] some illegal but tolerated locally. Some local authorities (e.g., flight clubs) offer periodic automated weather updates on these frequencies. In rare cases, pilots use radios to talk to airport control towers or air traffic controllers. Many pilots carry a cell phone so they can call for pickup should they land away from their intended point of destination.

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. The recorded GPS track of a flight can be used to analyze flying technique or can be shared with other pilots. GPS is also used 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. GPS is integrated with some models of variometer. This is not only more convenient, but also allows for a three-dimensional record of the flight. The flight track can be used as proof for record claims, replacing the "old" method of photo documentation.

Control
Speedbar mechanism

Brakes: Controls held in each of the pilot’s hands connect to the trailing edge of the left and right sides of the wing. These controls are called "brakes" and provide the primary and most general means of control in a paraglider. The brakes are used to adjust speed, to steer (in addition to weight shift), and to flare (during landing).

Weight Shift: In addition to manipulating the brakes, a paraglider pilot must also lean in order to steer properly. Such weight shifting can also be used for more limited steering when brake use is unavailable, such as when under "big ears" (see below). More advanced control techniques may also involve weight shifting.

Speed Bar: A kind of foot control called the "speed bar" (also "accelerator") attaches to the paragliding harness and connects to the leading edge of the paraglider wing, usually through a system of at least two pulleys (see animation in margin). This control is used to increase speed and does so by decreasing the wing's angle of attack. This control is necessary because the brakes can only slow the wing from what is called "trim speed" (no brakes applied). The accelerator is needed to go faster than this.

More advanced means of control can be obtained by manipulating the paraglider's risers or lines directly. Most commonly, the lines connecting to the outermost points of the wing's leading edge can be used to induce the wingtips to fold under. The technique, known as "big ears", is used to increase rate of descent (see picture and the full description below). The risers connecting to the rear of the wing can also be manipulated for steering if the brakes have been severed or are otherwise unavailable. For ground-handling purposes, a direct manipulation of these lines can be more effective and offer more control than the brakes. The effect of sudden wind blasts can be countered by directly pulling on the risers and making the wing unflyable, thereby avoiding falls or unintentional takeoffs.
Fast descents

Problems with “getting down” can occur when the lift situation is very good or when the weather changes unexpectedly. There are three possibilities of rapidly reducing altitude in such situations, each of which has benefits and issues to be aware of. The "big ears" maneuver induces descent rates of 2.5 to 3.5 m/s, 4–6 m/s with additional speed bar. It is the most controllable of the techniques and the easiest for beginners to learn. The B-line stall induces descent rates of 6–10 m/s. It increases loading on parts of the wing (the pilot's weight is mostly on the B-lines, instead of spread across all the lines). Finally, a spiral dive offers the fastest rate of descent, at 7–25 m/s. It places greater loads on the wing than other techniques do and requires the highest level of skill from the pilot to execute safely.

Big ears

Paraglider in "Big Ears" manoeuvre

    Pulling on the outer A-lines during non-accelerated, normal flight folds the wing tips inwards, which substantially reduces the glide angle with only a small decrease in forward speed. As the effective wing area is reduced, the wing loading is increased, and it becomes more stable. However, the angle of attack is increased, and the craft is closer to stall speed, but this can be ameliorated by applying the speed bar, which also increases the descent rate. When the lines are released, the wing re-inflates. If necessary, a short pumping on the brakes helps reentering normal flight. Compared to the other techniques, with big ears, the wing still glides forward, which enables the pilot to leave an area of danger. Even landing this way is possible, e.g., if the pilot has to counter an updraft on a slope.

B-line stall
    In a B-line stall, the second set of risers from the leading-edge/front (the B-lines) are pulled down independently of the other risers, with the specific lines used to initiate a stall. This puts a spanwise crease in the wing, thereby separating the airflow from the upper surface of the wing. It dramatically reduces the lift produced by the canopy and thus induces a higher rate of descent. This can be a strenuous maneuver, because these B-lines have to be held in this position, and the tension of the wing puts an upwards force on these lines. The release of these lines has to be handled carefully not to provoke a too fast forward shooting of the wing, which the pilot then could fall into.

Spiral dive
    The spiral dive is the most rapid form of controlled fast descent; an aggressive spiral dive can achieve a sink rate of 25 m/s. This maneuver halts forward progress and brings the flier almost straight down. The pilot pulls the brakes on one side and shifts his weight onto that side to induce a sharp turn. The flight path then begins to resembles a corkscrew. After a specific downward speed is reached, the wing points directly to the ground. When the pilot reaches his desired height, he ends this maneuver by slowly releasing the inner brake, shifting his weight to the outer side and braking on this side. The release of the inner brake has to be handled carefully to end the spiral dive gently in a few turns. If done too fast, the wing translates the turning into a dangerous upward and pendular motion.
    Spiral dives put a strong G-force on the wing and glider and must be done carefully and skilfully. The G-forces involved can induce blackouts, and the rotation can produce disorientation. Some high-end gliders have what is called a "stable spiral problem".[24] After inducing a spiral and without further pilot input, some wings do not automatically return to normal flight and stay inside their spiral. Serious injury and fatal accidents did occur when pilots could not exit this maneuver and spiraled into the ground.

Scootering

Freestyle scootering (also known as freestyle scootering, scootering, scooter riding, or simply riding) is an extreme sport which involves using kick scooters to perform freestyle tricks, in a manner similar to a mix of BMXing and skateboarding.

Origins
Mass-produced metal-framed scooters with pneumatic tyres were mass-produced by companies such as Radio Flyer and BMX and in widespread use by children until being eclipsed by the rise of the affordable higher status push bike and skateboard through the 1970s and early 1980s. The heavy and inflexible design and construction of such earlier scooters generally precluded the performance of tricks. In the 1990s, Gino Tsai with the Micro Mobility Systems and the JDBUG manufactured the first modern scooter. It was first distributed by The Sharper Image in 1999 and became popular in 2000. Razor USA was then founded in California,and quickly began to distribute Razor scooters as their own products. The company took off, quickly producing a lot of stylish and higher quality products. The first sponsored team was created in the same year, and released their first video titled "Razor Evolution." the scooter revolution began to get popular but then there was a noticeable decline in popularity of scootering in late 2001. Some riders continued and the sport began to grow again with a different image. One first major scooter competitions, SD1, was held in San Diego in 2006 and continues to one of the biggest scooter related events and competitions to date. After 2006, the most notable change was the physical evolution of the scooter. TSI Scooters was known to be the first company to produce the "One Piece Deck." This meant that the folding mechanism was replaced with a solid metal headtube which is usually welded directly to the deck of the scooter. From then until now, scooter companies continue to innovate with new techniques that make scooter parts lighter, stronger and better suited for the rider. The level at which professional scooter riders ride at is also constantly being raised in both skatepark and street riding. A "Maturation of Scootering" is currently taking place with more innovative parts and riding, as well a bigger and stronger community to back it up.

Terrain
Park

Kick scooters, due to their construction, can use most structures, or any structure that bikes or skateboards use,including rails, boxes and even vertical ramps that one would usually find in a skate park. Many riders enjoy riding 'flyout' to learn new tricks. Riders then take these tricks to different obstacles throughout the skatepark such as quarters, flyboxes, spines, rails, stairsets, ledges, hubbas, A-frames, banks and eurogaps. Some scooterers are notable for having more of a park style. Dakota "Kota" Schuetz is the current, unbeaten, three Time World Champion and the winningest rider in the sport. Some of the most talented park riders are Ryan Williams, Max Peters, Brendon Smith,Dylan Morrison,Vincent Kudrna, and Clayton Lindley. Many advanced tricks usually performed in a park setting include briflips, kickless rewinds, and flips. Anyone who scooters doesn't strictly ride street or park, but some riders find park riding more enjoyable than street riding.

Street

Inner city riders use structures such as stairs, ledges, hubbas, handrails, speedbumps, and gaps. Some street riders tend to get technical with tricks while others focus on sliding down large stair sets and handrails. Some of the most notable professionals who ride street currently are Matt McKeen, Erik Feenstra, Robert Mcmoran, Josh Young, Tom Kvilhaug, Jon Archer, Greg Cohen, Logan Fuller, Chema Cardenas, Jack Dona, Issac Miller, Zig Short, Cory Van Lew, Zack Martin, Elliott Arnold and many others. Streets are a versatile location to ride because they give the riders interesting obstacles to perform tricks on such as gap jumps, rail slides, combinations and lines that they would not normally do in a vertically styled skatepark. Whilst street riding, most scooter riders focus on cleanliness of tricks, or how easy it looks for a rider to do them. Street scooterers also focus on their style or original way of doing tricks. From late 2013 to present, there has a been a notable push for more people to ride ‘street’, much like skateboarding in the 90's. People still love riding skateparks for fun with their friends, but many scooterers ride street when they want to film a video part.

Flatland

The ‘flatland’ genre of freestyle scooter riding takes place on flat surfaces such as parking lots, driveways, or tennis/basketball courts. Flatland riders prefer to link smaller tricks up in "combos", or combinations, such as barspins, tailwhips, manuals, hang fives, fakies, scooter fakies, sliders, and more.

Dirt

Dirt Scootering is becoming increasingly popular. Many companies are releasing a model of scooter equipped for use on dirt jumps. These dirt scooters feature inflatable tires and intertubes much like BMX bikes.

Skiing

Skiing is a recreational activity and competitive winter sport in which the participant uses skis to glide on snow. Many types of competitive skiing events are recognized by the International Olympic Committee (IOC), and the International Ski Federation (FIS).

History
Spring ski touring on Hardangervidda, Norway
Main article: History of skiing

Skiing has a history of almost five millennia. Although modern skiing has evolved from beginnings in Scandinavia, it may have been practiced as early as 600 BC in what is now China.
The word "ski" is one of a handful of words Norway has exported to the international community. It comes from the Old Norse word "skíð" which means "split piece of wood or firewood".
Asymmetrical skis were used at least in northern Finland and Sweden up until the late 1800s. On one leg the skier wore a long straight non-arching ski for sliding, and on the other a shorter ski for kicking. The bottom of the short ski was either plain or covered with animal skin to aid this use, while the long ski supporting the weight of the skier was treated with animal fat in similar manner to modern ski waxing.

Early skiers used one long pole or spear. The first depiction of a skier with two ski poles dates to 1741.
Until the mid-1800s skiing was primarily used for transport, and since then has become a recreation and sport. Military ski races were held in Norway during the 18th century, and ski warfare was studied in the late 18th century. As equipment evolved and ski lifts were developed skiing evolved into two main genres in the 1930s, Alpine and Nordic.
Types of skiing
A collection of differing types of alpine skis, with nordic and telemark skis at far left. From right: a group of powder skis, a group of twin-tip skis, a group of carving (parabolic) skis, and then an older-type non-sidecut alpine ski along with the non-alpine skis.

Nordic
Main article: Nordic skiing

The Nordic disciplines include cross-country skiing and ski jumping, which share in common the use of binding that attach at the toes of the skier's boots but not at the heels. Cross-country skiing may be practiced on groomed trails or in undeveloped backcountry areas.

Alpine
Main article: Alpine skiing

Also called downhill skiing, alpine skiing typically takes place on a piste at a ski resort. It is characterized by fixed-heel bindings that attach at both the toe and the heel of the skier's boot. Because it is difficult to walk in alpine equipment, ski lifts including chairlifts bring skiiers up the slope. Backcountry skiing can be accessed by helicopter or snowcat. Facilities at resorts can include night skiing, après-ski, and glade skiing under the supervision of the ski patrol and the ski school. Alpine skiing branched off from the older Nordic skiing around the 1920s, when the advent of ski lifts meant that it was not necessary to walk any longer. Alpine equipment specialized to where it can only be used with the help of lifts.

Telemark
Main article: Telemark skiing

Telemark skiing is a ski turning technique and FIS-sanctioned discipline. It is named after the Telemark region of Norway. Using equipment similar to nordic skiing, the ski bindings having the ski boot attached only at the toe.
Competition

The following disciplines are sanctioned by the FIS. Many have their own world cups and are in the winter olympics.

    Cross-country: The sport encompasses a variety of formats for cross-country skiing races over courses of varying lengths. Such races occur over homologated, groomed courses designed to support classic (in-track) and free-style events, where the skiers may employ skate skiing. It also encompasses cross-country ski marathon events, sanctioned by the Worldloppet Ski Federation, and cross-country ski orienteering events, sanctioned by the International Orienteering Federation, and biathlon a combination of cross-country and shooting.
    Ski jumping: contested at the olympics, the FIS Ski Jumping World Cup, the summer FIS Grand Prix Ski Jumping, and the FIS Ski-Flying World Championships
    Nordic combined: contested at the olympics and at the FIS Nordic Combined World Cup, it is a combination of cross-country skiing and ski jumping.
    Alpine skiing discliplines include combined, downhill, slalom, giant slalom, Super-G, and Para-alpine.
    Freestyle skiing: includes mogul skiing, aerials, ski cross, half-pipe, and slopestyle.
    Snowboard competition includes slopestyle, cross, half-pipe, alpine, parallel slalom, and parallel giant slalom.

Other competition includes grass skiing and Telemark.

Equipment

Equipment used in skiing includes:

    Skis, which may have skins applied or be textured for uphill traction or wax applied for minimizing sliding friction. Twin-tip skis are designed to move forwards or backwards.
    Boots and bindings
    Poles
    Helmets and ski suits

Technique

Technique has evolved along with ski technology and ski geometry. Early techniques included the telemark turn, the stem, the stem Christie, snowplough, and parallel turn.

New parabolic designs like the Elan SCX have enabled the more modern carve turn.
Skiing without snow

Originally and primarily a winter sport, skiing can also be practised indoors without snow or outdoors on grass, on dry ski slopes, with ski simulators, or with roller skis.

Snowkiting

Snowkiting or Kiteboarding is an outdoor winter sport where people use kite power to glide on snow or ice. The sport is similar to water-based kiteboarding, but with the footwear used in snowboarding or skiing. In the early days of snowkiting, foil kites were the most common type; nowadays many kiteboarders use inflatable kites. Snowkiting differs from other alpine sports in that it is possible for the snowkiter to travel uphill and downhill with any wind direction. Like kiteboarding, snowkiting can be very hazardous and should be learned and practiced with care. Snowkiting is becoming increasingly popular in places often associated with skiing and snowboarding, such as Russia, Canada, Iceland, France, Switzerland, Austria, Norway, Sweden and the Northern and Central United States. The sport is becoming more diverse as adventurers use kites to travel great distances and sports enthusiasts push the boundaries of freestyle, big air, speed and back country exploration.

20th century

As a child Dieter Strasilla, inspired by Otto Lilienthal, practiced gliding around Berchtesgaden and in the 1960s he began parapente experiments (also with his brother Udo in USA) in Germany and Switzerland, parachute-skiing in 1972 and later perfected a kiteskiing system using self-made paragliders and a ball-socket swivel allowing the pilot to kitesail upwind or uphill, but also to take off into the air at will, swivelling the body around to face the right way.
Kiteskiers began kiteskiing on many frozen lakes and fields in the US midwest and east coast. Lee Sedgwick and a group of kiteskiers in Erie, PA were early ice/snow kiteskiers. In 1982 Wolf Beringer started developing his shortline Parawing system for skiing and sailing. This was used by several polar expeditions to kite-ski with sleds, sometimes covering large distances. Ted Dougherty began manufacturing 'foils' for kiteskiing and Steve Shapson of Force 10 Foils also began manufacturing 'foils' using two handles to easily control the kite. In the mid-1980s Shapson, while icesailing, took out an old two line kite and tried to ski upwind on a local frozen lake in Wisconsin. Shapson demonstrated the sport of 'kiteskiing' in Poland, Germany, Switzerland,Turkey and Finland. He also used grass skis to kiteski on grassy fields. Early European kiteskiers were Keith Stewart and Theo Schmidt, who also was among the first to waterski with kites. American Cory Roeseler together with his father William developed a Kiteski system for waterskiing and began winning in windsurf races featuring high following winds, such as in the gorge of the Columbia river. The following terms describe the sport of 'Traction Kiting' or some refer to as 'Power Kiting': Kite buggying, kite skiing, kitesurfing and kite landboarding.

In the mid-1980s e.g. some alpine skiers used a rebridled square parachute to ski upwind on a frozen bay in Erie, PA.[citation needed] In the late 1990s small groups of French and North American riders started pushing the boundaries of modern freestyle snowkiting. The Semnoz crew from France began hosting events at the Col du Lautaret and other European sites where the mountainous terrain lent itself to "paragliding" down the hills. In North America, riders were mainly riding snow-covered lakes and fields where tricks were being done on the flat ground, jumps, rails and sliders.

21st century

The 2000s have seen a giant leap forward in snowkite-specific technologies, skill levels and participants in every possible snow-covered country. The development of snowkite specific, de-powerable, foil kites have allowed snowkiters to explore further and push the limits of windpowered expeditions. Recent crossings in record times of large snowfields and even Greenland have been accomplished through the use of snowkites.

On the forefront of extreme freestyle snowkiting, dedicated snowkiting communities from Utah to Norway are pushing the freestyle envelope and documenting their efforts through films like Something Stronger and Dimensions, and Snowkite Magazine which is available as a digital magazine. The extreme envelope of snowkiting freestyle and back country is being pushed by Chasta, a French kiter sponsored by Ozone Kites now based in New Zealand.

Better equipment, safety practices, community know-how and qualified instructors are readily available in many areas, allowing people to learn properly and safely through different means than trial and error. The sport is currently being enjoyed by kiters of all ages and in a wide variety of activities ranging from mellow jaunts on a lake, to kitercross events, from multi-day expeditions, to flying off mountains, from freestyle jib tricks, to huge cliff jumps as well as endurance and course racing.

There is a small segment of kiters that participate in GPS speed competitions where kiters record speed data on a GPS unit and submit it to a coordinating body for comparison to other kiter's speeds. In the Stormboarding[6] world wide speed ranking Joe Levins, an American kiter, was the first to reach 70 mph/112 kph in 2008. In 2009 Christopher Krug, an American kiter sponsored by Peter Lynn Kiteboarding[7] pushed the envelope further to a speed of 73.5 mph/118 kph.
Technique and Ride

The technique of kite surfing is very similar to basic snowboarding, except it is at a higher level of difficulty. It is very much like windsurfing except with a snowboard under your feet. It is harder to keep balance at the minimum, as your arms can't be entirely devoted to balance, although this can be offset to a degree due to the up-and forward-force generated from the kite, depending on the wind and size of your kite. Also, to effectively kitesurf on a snowboard, you need to have a snowboard with the least amount (preferably none) of side cut, to avoid inadvertently riding upwind. (Because, as you lean back to be a counterweight against the force of the kite, your heels naturally dig in the snow forcing the board to turn upwind) Although the new reverse camber snowboards have made it possible to have more side cut in snowboard.
Terrain

Kite Boarding is practical on very many areas, as long as there is a significant amount of wind to keep the kite up. It is not always used on slopes, and can in fact be used with no slope, or even an upwards slope, as long as there is enough wind to offset the drag incurred. It can prove more difficult to have any riding time when you go on a steeper slope, as the wind can be blocked and or become turbulent passing over the peak of the hill, causing the kite to behave erratically and even fall or be pushed to the ground

Surfing

Surfing is a surface water sport in which the wave rider, referred to as a surfer, rides on the forward or deep face of a moving wave, which is usually carrying the surfer toward the shore. Waves suitable for surfing are primarily found in the ocean, but can also be found in lakes or in rivers in the form of a standing wave or tidal bore. However, surfers can also utilize artificial waves such as those from boat wakes and the waves created in artificial wave pools.

The term surfing refers to the act of riding a wave, regardless of whether the wave is ridden with a board or without a board, and regardless of the stance used (goofy or regular stance). The native peoples of the Pacific, for instance, surfed waves on alaia, paipo, and other such craft, and did so on their belly and knees. The modern-day definition of surfing, however, most often refers to a surfer riding a wave standing up on a surfboard; this is also referred to as stand-up surfing.

One variety of stand-up surfing is paddle boarding. Another prominent form of surfing is body boarding, when a surfer rides a wave on a bodyboard, either lying on their belly, drop knee, or sometimes even standing up on a body board. Other types of surfing include knee boarding, surf matting (riding inflatable mats), and using foils. Body surfing, where the wave is surfed without a board, using the surfer's own body to catch and ride the wave, is very common and is considered by some to be the purest form of surfing.

Three major subdivisions within standing-up surfing are long boarding, short boarding, and stand up paddle surfing (SUP), and these three have several major differences, including the board design and length, the riding style, and the kind of wave that is ridden.

In tow-in surfing (most often, but not exclusively, associated with big wave surfing), a motorized water vehicle, such as a personal watercraft, tows the surfer into the wave front, helping the surfer match a large wave's speed, which is generally a higher speed than a self-propelled surfer can produce. Surfing-related sports such as paddle boarding and sea kayaking do not require waves, and other derivative sports such as kite surfing and windsurfing rely primarily on wind for power, yet all of these platforms may also be used to ride waves. Recently with the use of V-drive boats, Wakesurfing, in which one surfs on the wake of a boat, has emerged. The Guinness Book of World Records recognized a 78 feet (23.8 m) wave ride by Garrett McNamara at Nazaré, Portugal as the largest wave ever surfed, although this remains an issue of much contention amongst many surfers, given the difficulty of measuring a constantly changing mound of water.

Origins and history

For centuries, surfing was a central part of ancient Polynesian culture. Surfing may have first been observed by Europeans at Tahiti in 1767 by Samuel Wallis and the crew members of the Dolphin who were the first Europeans to visit the island in June of that year. Another candidate is the botanist Joseph Banks being part of the first voyage of James Cook on the HMS Endeavour, who arrived on Tahiti on 10 April 1769. Lieutenant James King was the first person to write about the art of surfing on Hawaii when he was completing the journals of Captain James Cook upon Cook's death in 1779.

When Mark Twain visited Hawaii in 1866 he wrote,

In one place we came upon a large company of naked natives, of both sexes and all ages, amusing themselves with the national pastime of surf-bathing.

References to surf riding on planks and single canoe hulls are also verified for pre-contact Samoa, where surfing was called fa'ase'e or se'egalu (see Augustin Krämer, The Samoa Islands) and Tonga far pre-dating the practice of surfing by Hawaiians and eastern Polynesians by over a thousand years.

In July 1885, three teenage Hawaiian princes took a break from their boarding school, St. Mathew’s Hall in San Mateo, and came to cool off in Santa Cruz, California. There, David Kawananakoa, Edward Keliiahonui and Jonah Kuhio Kalaniana'ole surfed the mouth of the San Lorenzo River on custom-shaped redwood boards, according to surf historians Kim Stoner and Geoff Dunn.

George Freeth (8 November 1883 – 7 April 1919) is often credited as being the "Father of Modern Surfing". He is thought to have been the first modern surfer.

In 1907, the eclectic interests of the land baron Henry Huntington brought the ancient art of surfing to the California coast. While on vacation, Huntington had seen Hawaiian boys surfing the island waves. Looking for a way to entice visitors to the area of Redondo Beach, where he had heavily invested in real estate, he hired a young Hawaiian to ride surfboards. George Freeth decided to revive the art of surfing, but had little success with the huge 16-foot hardwood boards that were popular at that time. When he cut them in half to make them more manageable, he created the original "Long board", which made him the talk of the islands. To the delight of visitors, Freeth exhibited his surfing skills twice a day in front of the Hotel Redondo.

In 1975, professional contests started. That year Margo Oberg became the first female professional surfer.

Surf waves

Photo of surfer catapulted from now-inverted board
A surfer wipes out
Photo showing surfer inside the curl of a breaking wave in turbulent waters
A surfer inside the curl of a wave that is breaking
Photo of taller-than-human-sized wave breaking with several watching surfers in foreground
A large wave breaking
Swell is generated when wind blows consistently over a large area of open water, called the wind's fetch. The size of a swell is determined by the strength of the wind and the length of its fetch and duration. Because of this, surf tends to be larger and more prevalent on coastlines exposed to large expanses of ocean traversed by intense low pressure systems.

Local wind conditions affect wave quality, since the surface of a wave can become choppy in blustery conditions. Ideal conditions include a light to moderate "offshore" wind, because it blows into the front of the wave, making it a "barrel" or "tube" wave. Waves are Left handed and Right Handed depending upon the breaking formation of the wave.

Waves are generally recognized by the surfaces over which they break. For example, there are Beach breaks, Reef breaks and Point breaks.

The most important influence on wave shape is the topography of the seabed directly behind and immediately beneath the breaking wave. The contours of the reef or bar front becomes stretched by diffraction. Each break is different, since each location's underwater topography is unique. At beach breaks, sandbanks change shape from week to week. Surf forecasting is aided by advances in information technology. Mathematical modeling graphically depicts the size and direction of swells around the globe.

Swell regularity varies across the globe and throughout the year. During winter, heavy swells are generated in the mid-latitudes, when the North and South polar fronts shift toward the Equator. The predominantly Westerly winds generate swells that advance Eastward, so waves tend to be largest on West coasts during winter months. However, an endless train of mid-latitude cyclones cause the isobars to become undulated, redirecting swells at regular intervals toward the tropics.

East coasts also receive heavy winter swells when low-pressure cells form in the sub-tropics, where slow moving highs inhibit their movement. These lows produce a shorter fetch than polar fronts, however they can still generate heavy swells, since their slower movement increases the duration of a particular wind direction. The variables of fetch and duration both influence how long wind acts over a wave as it travels, since a wave reaching the end of a fetch behaves as if the wind died.

During summer, heavy swells are generated when cyclones form in the tropics. Tropical cyclones form over warm seas, so their occurrence is influenced by El Niño & La Niña cycles. Their movements are unpredictable.

Surf travel and some surf camps offer surfers access to remote, tropical locations, where tradewinds ensure offshore conditions. Since winter swells are generated by mid-latitude cyclones, their regularity coincides with the passage of these lows. Swells arrive in pulses, each lasting for a couple of days, with a few days between each swell.

The availability of free model data from the NOAA has allowed the creation of several surf forecasting websites.

Windsurfing

Windsurfing is a surface water sport that combines elements of surfing and sailing. It consists of a board usually 2 to 3 meters long, with a volume of about 60 to 250 liters, powered by wind on a sail. The rig is connected to the board by a free-rotating universal joint and consists of a mast, 2-sided boom and sail. The sail area generally ranges from 2.5 m2 to 12 m2 depending on the conditions, the skill of the sailor and the type of windsurfing being undertaken.

Some credit S. Newman Darby with the origination of windsurfing by 1964 on the Susquehanna River, Pennsylvania, USA when he invented the "sailboard", which, incidentally, he did not patent. In 1964, Darby began selling his sailboards. A promotional article by Darby was published in the August 1965 edition of Popular Science magazine.

While Darby's "sailboard" incorporated a pivoting rig, it was "square rigged" and suffered all the associated limitations. You operated the sailboard with your back to the lee side of the kite shaped square sail. Darby's article boasted that "...you can learn to master a type of manoeuvering that's been dead since the age of the picturesque square riggers"


Darby sailboard, Popular Science, 1965
Windsurfing can be said to straddle both the laid-back culture of surf sports and the more rules-based environment of sailing. Although it might be considered a minimalistic version of a sailboat, windsurfing offers experiences that are outside the scope of other sailing craft designs. Windsurfers can perform jumps, inverted loops, spinning maneuvers, and other "freestyle" moves that cannot be matched by any sailboat. Windsurfers were the first to ride the world's largest waves, such as Jaws on the island of Maui, and, with very few exceptions, it was not until the advent of tow-in surfing that waves of that size became accessible to surfers on more traditional surfboards. Extreme waves aside, many expert windsurfers will ride the same waves as wavesurfers do (wind permitting) and are themselves usually very accomplished without a rig on a conventional surfboard.

At one time referred to as "surfing's ginger haired cousin" by the sport's legendary champion, Robby Naish, windsurfing has long struggled to present a coherent image of the sport to outsiders. As a result of attempts to claim the word "windsurfer" as a trademark, participants have been encouraged to use different names to describe the sport, including "sailboarding" and "boardsailing". The term "windsurfing" has persisted as the accepted name for the sport, and the word "windsurfer" persists for both participants and equipment.

Windsurfing is predominately undertaken on a non-competitive basis. Organised competition does take place at all levels across the world and typical formats for competitive windsurfing include Formula Windsurfing, speed sailing, slalom, course racing, wave sailing, superX, and freestyle. These events are exciting to watch as sailors push the limits both physically and creatively with moves that look as impossible as thinking them up in the first place.

The boom of the 1980s led windsurfing to be recognized as an Olympic sport in 1984. However, windsurfing's popularity saw a sharp decline in the mid-1990s, thanks to licensing battles, and equipment becoming more specialized and requiring more expertise to sail. The sport experienced a modest revival, as new beginner-friendly designs became available. Further pressure came as a proportion of avid windsurfers took up the similar sport of kitesurfing.

Windsurfing International
On March 27, 1968, Hoyle Schweitzer and Jim Drake filed the very first windsurfing patent, which was granted by the USPTO in 1970. There is no evidence that they had knowledge of any prior inventions similar to theirs, but Drake accepted in retrospect that although he can be credited with invention, he was "probably no better than third," behind mid-west based Newman Darby and Englishman Peter Chilvers.

The early windsurfing boards were made of foam in the garages of Schweitzer and Drake, with the booms, tees and daggerboards hand crafted in teak. Hoyle sub-contracted the manufacture of the teak items to boat builder Ennals Ives in Taiwan, but the quality and costs of transportation brought other issues. One of the early customers was Bert Salisbury, and the first international shipment of a container of boards went to Sweden. Early customers also included Lufthansa pilots who had read about the board, who simply included one as personal luggage on their return journey from Los Angeles International Airport.

To ensure the quality of the product and handle marketing, in 1968 Hoyle and Diana Schweitzer founded the company Windsurfing International in Southern California to manufacture, promote and license a windsurfer design. The jointly owned patent was wholly licensed to Windsurfing International. Working in a factory unit in Torrance, California, Hoyle, who had previously built personal surf boards in his garage, was unhappy with the durability of the early "Baja Board." He therefore developed a new mould, based on an old Malibu surfboard design that Matt Kivlin had developed, which the company sub-contracted for mass manufacture to Elmer Good.

The company registered the term "windsurfer" as a trademark at the United States Patent and Trademark Office in 1973, launching the craft as a one-design class. Going one-design was influenced by the success of the Laser and Hobie Cat classes. Each Windsurfer had an identical computer-cut sail, a technology new at that time and pioneered by Ian Bruce and the Laser class.

In 1968, Hoyle's computer business collapsed, and he and Diane moved to Newport Beach; at the same time Drake accepted a two-year assignment to The Pentagon, and moved to Washington DC. Immediately, Hoyle offered Drake to buy out his half of the patent, and it was only when Hoyle pointed out ownership of the company that the relationship between the pair began to fall apart. Having returned to California, in 1973 Drake sold his half of the patent to Windsurfing International for the sum of $36,000.

Patent disputes
Through the seventies, Schweitzer aggressively promoted and licensed the Windsurfing International design and licensed the patent to manufacturers worldwide, mainly through competition and the publication of a magazine. As a result, the sport underwent very rapid growth, particularly in Europe after the sale of a sub-license sold to Ten Cate in the Netherlands.

At the same time, Schweitzer also sought to defend his patent rights vigorously against unauthorized manufacturers. This led to a host of predating windsurfer-like devices being presented to courts around the world by companies disputing Windsurfing International's rights to the invention.

(In 1979, Schweitzer licensed Brittany, France-based company Dufour Wing, which was later merged with Tabur Marine – the precursor of Bic Sport. Dufour was not licenced!) Europe was now the largest growing market for windsurfers, and the sub-licensed companies – Tabur, F2, Mistral – wanted to find a way to remove or reduce their royalty payments to Windsurfing International.

Tabur lawyers found prior art, in a local English newspaper which had published a story with a picture about Peter Chilvers, who as a young boy on Hayling Island on the south coast of England, assembled his first board combined with a sail, in 1958. This board used a universal joint, one of key parts of the Windsurfing International's patent. They also found stories published about the 1948 invention of the sailboard by Newman Darby and his wife Naomi in Wilkes-Barre, Pennsylvania.

In Windsurfing International Inc. v Tabur Marine (GB) Ltd. 1985 RPC 59, with Tabur backed financially by French sailing fan Baron Marcel Bich, British courts recognized the prior art of Peter Chilvers. It did not incorporate the curved wishbone booms of the modern windsurfer, but rather a "straight boom" that became curved in use. The courts found that the Schweitzer windsurfer boom was "merely an obvious extension". It is worthy of note that this court case set a significant precedent for patent law in the United Kingdom, in terms of inventive step and non-obviousness; the court upheld the defendant's claim that the Schweitzer patent was invalid, based on film footage of Chilvers. Schweitzer then sued the company in Canada, where the opposition team again financially backed by Bic included Chilvers and Jim Drake, and Schweitzer lost again. After the cases, no longer obliged to pay Windsurfing International any royalty payments, the now renamed Bic Sport became the world’s largest producer of windsurfing equipment, with an annual production of 15,000 boards.

In 1983, Schweitzer sued Swiss board manufacturer Mistral and lost. Mistral's defense hinged on the work of US inventor Newman Darby, who by 1965 conceived the "sailboard": a hand-held square rigged "kite" sail on a floating platform for recreational use.

Eventually US courts recognized the Schweitzer windsurfer as an obvious step from Darby's prior art. Schweitzer had to reapply for a patent under severely limited terms, and finally it expired in 1987. Shortly thereafter, having lost its license royalty income, Windsurfing International ceased operations.

In 1984, Australian courts determined a patent case: Windsurfing International Inc & Anor -v- Petit & Anor (also part reported in 3 IPR 449 or [1984] 2 NSWLR 196), which attributed the first legally accepted use of a split boom to an Australian boy, Richard Eastaugh. Between the ages of ten and thirteen, from 1946 to 1949, aided by his younger brothers, he built around 20 galvanized iron canoes and hill trolleys which he equipped with sails with split bamboo booms. He sailed these in a sitting position and not as a windsurfer standing up, near his home on the Swan River in Perth. The judge noted that, "Mr Eastaugh greatly exaggerated the capacity of his galvanised iron canoes to sail to windward" and that, "There is no corroboration of Mr Eastaugh's experiences by any other witness. Neither of his brothers or his father was called".

It is acknowledged in the courts that the separate Eastaugh (1946–1949), Darby (1965) and Chilvers (1958) inventions pre-dated the Schweitzer/Drake patent (1968).

Trademark disputes
Windsurfing International claimed trademark rights with respect to the word "windsurfer". While this was registered in the United States for some years, it was not accepted for registration in many jurisdictions as the word was considered too descriptive. Registration was ultimately lost in the United States for the same reason.

The Schweitzers initially chose the word for its descriptive quality. Unfortunately they immediately set out diminishing its value by naming their company "Windsurfing International" and even referring to themselves and their own children as "windsurfers".

As the word was rejected as registrable in a number of countries, lawyers advised that to be successful the word would have to be used as a proper adjective. They realised that this required a number of generic nouns to which the adjective would apply: sailboard, boardsailing, planche a voile, segelbrett and so on. The rearguard action was ultimately unsuccessful and arguably created considerable confusion which hampered marketing efforts in later years.

Marketing
While the numerous patent and trademark disputes have left an unfortunate legacy, the fact is that these disputes did not occur until well after Windsurfing International, its licensees, class associations, retailers, schools and owners had built the sport to a successful commercial basis. That success bought imitation and then legal disputes.

The launch phase saw a comprehensive development of infrastructure for a new sport and dramatic sales growth.

Wingsuit flying

Wingsuit flying (or wingsuiting) is the sport of flying through the air using a wingsuit, which adds surface area to the human body to enable a significant increase in lift. The modern wingsuit, first developed in the late 1990s, creates a surface area with fabric between the legs and under the arms. Wingsuits are sometimes referred to as "birdman suits" (after the makers of the first commercially available wingsuit), "flying squirrel suits" (due to their resemblance to the animal), and "bat suits" (due to their vague resemblance to the animal or perhaps the superhero).

A wingsuit flight normally ends by deploying a parachute, and so a wingsuit can be safely flown from any point that provides sufficient altitude for flight and parachute deploymentnormally a skydiving drop aircraft, or BASE-jump exit point. The wingsuit flier wears parachute equipment specially designed for skydiving or BASE jumping. While the parachute flight is normal, the canopy pilot typically unzips arm wings (after deployment) to be able to reach the steering parachute toggles and control the descent path.

History

An early attempt at wingsuit flying was made on 4 February 1912 by a 33-year-old tailor, Franz Reichelt, who jumped from the Eiffel Tower to test his invention of a combination of parachute and wing, which was similar to modern wingsuits. He misled the guards by saying that the experiment was going to be conducted with a dummy. He hesitated quite a long time before he jumped, and hit the ground head first, opening a measurable hole in the frozen ground, but an autopsy showed that he died of a heart attack before hitting the pavement. A film of his attempt exists.

A wingsuit was first used in 1930 by a 19-year-old American, Rex Finney, of Los Angeles, California, as an attempt to increase horizontal movement and maneuverability during a parachute jump. These early wingsuits were made of materials such as canvas, wood, silk, steel, and whalebone. They were not very reliable, although some "birdmen", notably Clem Sohn and Leo Valentin, claimed to have glided for miles.

In the mid-1990s, the modern wingsuit was developed by Patrick de Gayardon of France, adapted from the model used by John Carta. In 1997, the Bulgarian Sammy Popov designed and built a wingsuit which had a larger wing between the legs and longer wings on the arms. His prototype was developed at Boulder City, Nevada. Testing was conducted in a vertical wind tunnel in Las Vegas at Flyaway Las Vegas. Popov's wingsuit first flew in October 1998 over Jean, Nevada, but it never went into commercial production. Popov's design was a great improvement in creating lift; it was able to slow the vertical speed to 30 km/h while gliding horizontally at speeds over 300 km/h. In 1998, Chuck "Da Kine" Raggs built a version which incorporated hard ribs inside the wing airfoils. Although these more rigid wings were better able to keep their shape in flight, this made the wingsuit heavier and more difficult to fly. Raggs' design also never went into commercial production. Flying together for the first time, Popov and Raggs showcased their designs side-by-side at the World Free-fall Convention at Quincy, Illinois, in August 1999. Both designs performed well. At the same event, multiple-formation wingsuit skydives were made which included de Gayardon's, Popov's, and Raggs' suits.

Commercial era

In 1999, Jari Kuosma of Finland and Robert Pečnik of Slovenia teamed up to create a wingsuit that was safe and accessible to all skydivers. Kuosma established Bird-Man International Ltd. the same year. BirdMan's "Classic", designed by Pečnik, was the first wingsuit offered to the general skydiving public. BirdMan was the first manufacturer to advocate the safe use of wingsuits by creating an instructor program. Created by Kuosma, the instructor program's aim was to remove the stigma that wingsuits were dangerous and to provide wingsuit beginners (generally, skydivers with a minimum of 200 jumps) with a way to safely enjoy what was once considered the most dangerous feat in the skydiving world. With the help of Birdman instructors Scott Campos, Chuck Blue and Kim Griffin, a standardized program of instruction was developed that prepared instructors. Phoenix-Fly, Fly Your Body, and Nitro Rigging have also instituted an instructor training program.

Despite the training and regulation, wingsuit BASE jumping remains a precarious pastime. A 2012 University of Colorado study found that for Wingsuit BASE jumping (WiSBASE) there were approximately 2 severe injuries per 1000 jumps, or with jumpers having an average of 1 severe injury for every 500 jumps they undertake.

Technical mechanics

Wingsuits in flight

The wingsuit flier enters free fall wearing both a wingsuit and parachute equipment. Exiting an aircraft in a wingsuit requires skilled techniques that differ depending on the location and size of the aircraft door. These techniques include the orientation relative to the aircraft and the airflow while exiting, and the way in which the flier spreads his legs and arms at the proper time so as not to hit the aircraft or become unstable. The wingsuit immediately starts to fly upon exiting the aircraft in the relative wind generated by the forward speed of the aircraft. Exiting from a BASE jumping site, such as a cliff, or exiting from a helicopter, a paraglider, or a hot air balloon, is fundamentally different from exiting a moving aircraft, as the initial airspeed upon exit is absent. In these situations, a vertical drop using the forces of gravity to accelerate is required to generate the airspeed that the wingsuit then converts to lift.

At a planned altitude above the ground in which a skydiver or BASE jumper typically deploys the parachute, wingsuit fliers will also deploy their parachutes. The parachute is flown to a controlled landing at the desired landing spot using typical skydiving or BASE jumping techniques.

A wingsuit modifies the body area exposed to wind to increase the desired amount of lift with respect to drag generated by the body. An attainable glide ratio of some wingsuits is 2.5:1 or more[citation needed]. This means that for every meter dropped, two and a half meters are gained moving forward. This ratio can be referred to as flight efficiency. With body shape manipulation and by choosing the design characteristics of the wingsuit, fliers can alter both their forward speed and fall rate. The pilot manipulates these flight characteristics by changing the shape of the torso, de-arching and rolling the shoulders and moving hips and knees, and by changing the angle of attack in which the wingsuit flies in the relative wind, and by the amount of tension applied to the fabric wings of the suit. The absence of a vertical stabilizing surface results in little damping around the yaw axis, so poor flying technique can result in a spin that requires active effort on the part of the skydiver to stop.

A wingsuit flyer over Palm Islands, Dubai

Wingsuit fliers can measure their performance relative to their goals with the use of free fall computers that record the amount of time they were in flight, the altitude they deployed their parachute, and the altitude they entered free fall. The fall rate speed can be calculated from this data and compared to previous flights. GPS receivers can also be used to plot and record the flight path of the suit, and when analyzed, can indicate the amount of distance flown during the flight. BASE jumpers can use landmarks on exit points, along with recorded video of their flight by ground crews, to determine their performance relative to previous flights and the flights of other BASE jumpers at the same site.

A typical skydiver's terminal velocity in belly to earth orientation ranges from 180–225 km/h (110 to 140 mph). A wingsuit can reduce these speeds dramatically. A vertical instantaneous velocity of 40 km/h (25 mph) has been recorded[citation needed]. However the speed at which the body advances forward through the air is still much higher.

The tri-wing wingsuit has three individual ram-air wings attached under the arms and between the legs. The mono-wing wingsuit design incorporates the whole suit into one large wing.