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Parachuting, or skydiving, is the action sport 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.
A skydiving center can be a commercial operation or a club, usually operates at an airport, and provides one or more aircraft that takes groups of skydivers up for a fee. An individual jumper can go up in a light aircraft such as a Cessna 172 or Cessna 182. At busier drop zones (DZs) larger turbine-powered aircraft may be used: such as the Cessna 208, de Havilland Canada DHC-6 Twin Otter, GippsAero GA8 Airvan or Short SC.7 Skyvan.
A typical sport parachuting jump involves individuals exiting an aircraft (usually an airplane, but sometimes a helicopter or even the gondola of a balloon), at anywhere from 1,000 to 4,000 meters (3,000 to 13,000 feet) altitude. If jumping from a low altitude, the parachute is usually deployed immediately; however, at higher altitudes, the skydiver may free-fall for up to ~1 minute  deploying their main parachute, typically at an altitude of 1000m (~3,500 ft), and landing several minutes later.
After the parachute opens, the jumper can control the direction and speed with toggles on the end of steering lines that attach to the trailing edge of the parachute, and can aim for the landing site and come to a relatively gentle stop. All modern sport parachutes are self-inflating "ram-air" wings that provide control of speed and direction similar to the related paragliders. Parachutes however generate less lift, and thus have less range, than paragliders, as their design must also consider the need to absorb the stresses of deployment at terminal velocity (~190 km/h in a belly-to-earth position).
By manipulating the shape of the body in freefall, a skydiver can generate turns, forward motion, backwards motion, and even lift (relative to other jumpers, not the ground).
When leaving an aircraft, for a few seconds a skydiver continues to travel forward as well as down, due to the momentum imparted by the aircraft's motion (known as "forward throw"). The perception of a change from horizontal to vertical flight is known as the "relative wind", or informally as "being on the hill". In freefall, skydivers generally do not experience a "falling" sensation because the resistance of the air to their body at speeds above about 80 km/h (50 mph) provides some feeling of weight and direction. At normal exit speeds for aircraft (approx 140 km/h (90 mph)) there is little feeling of falling just after exit, but jumping from a relatively stationary balloon or helicopter can create this sensation. Skydivers reach terminal velocity (around 190 km/h (120 mph) for belly to Earth orientations, 240–320 km/h (150–200 mph) for head down orientations) and are no longer accelerating towards the ground. At this point the sensation is as of a forceful wind.
Many people make their first jump with an experienced and trained instructor – this type of skydive may be in the form of a tandem skydive. During the tandem jump the instructor is responsible for emergency procedures in the unlikely event that they will be needed, therefore freeing the student to concentrate on learning to skydive. Other training methods include static line, IAD (Instructor Assisted Deployment), and AFF (Accelerated Free fall) also known as Progressive Free-Fall (PFF) in Canada.
Despite the perception of danger, fatalities are rare. However, each year a number of people are hurt or killed parachuting worldwide. About 21 skydivers are 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. 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.
Parachuting in poor weather, especially with thunderstorms, high winds, and dust devils can be a dangerous activity. Reputable drop zones will suspend normal operations during inclement weather. In the United States, the USPA's Basic Safety Requirements prohibit solo student skydivers from jumping in winds exceeding 14 mph while using ram-air equipment. However, maximum ground winds are unlimited for licensed skydivers.
A collision with another canopy is a statistical hazard, and may be avoided by observing simple principles. In 2013, 17% of all skydiving fatalities in the United States resulted from mid-air collisions.
Skydiving can be practiced without jumping. Vertical wind tunnels are used to practice for free fall ("indoor skydiving" or "bodyflight"), while virtual reality parachute simulators are used to practise parachute control.
Beginning skydivers seeking training have the following options:
At a sport skydiver's deployment altitude, the individual manually deploys a small pilot-chute which acts as a drogue, catching air and pulling out the main parachute or the main canopy. There are two principal systems in use: the "throw-out", where the skydiver pulls a toggle attached to the top of the pilot-chute stowed in a small pocket outside the main container: and the "pull-out", where the skydiver pulls a small pad attached to the pilot-chute which is stowed inside the container.
Throw-out pilot-chute pouches are usually positioned at the bottom of the container – the B.O.C. deployment system – but older harnesses often have leg-mounted pouches. The latter are safe for flat-flying, but often unsuitable for freestyle or head-down flying.
In a typical civilian sport parachute system, the pilot-chute is connected to a line known as the "bridle", which in turn is attached to a small deployment bag that contains the folded parachute and the canopy suspension lines, which are stowed with rubber bands. At the bottom of the container that holds the deployment bag is a closing loop which, during packing, is fed through the grommets of the four flaps that are used to close the container. At that point, a curved pin that is attached to the bridle is inserted through the closing loop. The next step involves folding the pilot-chute and placing it in a pouch (e.g., B.O.C pouch).
Activation begins when the pilot chute is thrown out. It inflates and creates drag, pulling the pin out of the closing loop and allowing the pilot-chute to pull the deployment bag from the container. The parachute lines are pulled loose from the rubber bands and extend as the canopy starts to open. A rectangular piece of fabric called the "slider" (which separates the parachute lines into four main groups fed through grommets in the four respective corners of the slider) slows the opening of the parachute and works its way down until the canopy is fully open and the slider is just above the head of the skydiver. The slider slows and controls the deployment of the parachute. Without a slider, the parachute would inflate fast, potentially damaging the parachute fabric and/or suspension lines. During a normal deployment, a skydiver will generally experience a few seconds of intense deceleration, in the realm of 3 to 4 G, while the parachute slows the descent from 190 km/h (120 mph) to approximately 28 km/h.
If a skydiver experiences a malfunction of their main parachute which they cannot correct, they pull a "cut-away" handle on the front right-hand side of their harness (on the chest) which will release the main canopy from the harness/container. Once free from the malfunctioning main canopy, the reserve canopy can be activated manually by pulling a second handle on the front left harness. Some containers are fitted with a connecting line from the main to reserve parachutes – known as a reserve static line (RSL) – which pulls open the reserve container faster than a manual release could. Whichever method is used, a spring-loaded pilot chute then extracts the reserve parachute from the upper half of the container.
One example of this is "Hit and Rock", a variant of Accuracy landing devised to let people of varying skill levels compete for fun. "Hit and Rock" is originally from POPS (Parachutists Over Phorty Society). See the POPS main site. The object is to land as close as possible to the chair, remove the parachute harness, sprint to the chair, sit fully in the chair and rock back and forth at least one time. The contestant is timed from the moment that feet touch the ground until that first rock is completed. This event is considered a race.
Atmonauti is a human flight technique invented by Marco Tiezzi in 1998. Developed and perfected with the help of Gigliola Borgnis, it was presented for the first time in 2000 at the World Freestyle Competitions, the European Espace Boogie, and the Eloy Freefly Festival.
The technique consists of flying diagonal with a determinate relation between angle and trajectory speed of the body, to obtain an air stream that permits lift and a precise control of flight. The aim is to fly in formation at the same level and angle, and to be able to perform different aerial games, such as freestyle, three-dimensional flight formation with grip, or acrobatic freeflying.
In camera flying, a camera person jumps with other skydivers and films them. The camera flier often wears specialized equipment, such as a winged jumpsuit to provide a greater range of fall rates, helmet-mounted video and still cameras, mouth operated camera switches, and optical sights. Some skydivers specialize in camera flying and a few earn fees for filming students on coached jumps or tandem-jumpers, or producing professional footage and photographs for the media.
There is always a demand for good camera fliers in the skydiving community, as many of the competitive skydiving disciplines are judged from a video record.
A cross-country jump is a skydive where the participants open their parachutes immediately after jumping, with the intention of covering as much ground under canopy as possible. Usual distance from Jump Run to the dropzone can be as much as several miles.
Formation skydiving was born in California, USA during the 1960‘s. The first documented skydiving formation occurred over Arvin, California in March of 1964 when Mitch Poteet, Don Henderson, Andy Keech, and Lou Paproski successfully formed a 4-man star formation, photographed by Bob Buquor. This discipline is commonly referred to in the skydiving community as "relative work".
Parachuting is not always restricted to daytime hours; experienced skydivers sometimes perform night jumps. For safety reasons, this requires more equipment than a usual daytime jump and in most jurisdictions it requires both an advanced skydiving license (at least a B-License in the U.S.) and a meeting with the local safety official covering who will be doing what on the load. A lighted altimeter (preferably accompanied with an audible altimeter) is a must. Skydivers performing night jumps often take flashlights up with them so that they can check their canopies have properly deployed.
Visibility to other skydivers and other aircraft is also a consideration; FAA regulations require skydivers jumping at night to be wearing a light visible for three miles (5 km) in every direction, and to turn it on once they are under canopy. A chem-light(glowstick) is a good idea on a night jump.
Night jumpers should be made aware of the Dark Zone, when landing at night. Above 30 meters (100 feet) jumpers flying their canopy have a good view of the landing zone normally because of reflected ambient light/moon light. Once they get close to the ground, this ambient light source is lost, because of the low angle of reflection. The lower they get, the darker the ground looks. At about 100 feet and below it may seem that they are landing in a black hole. Suddenly it becomes very dark, and the jumper hits the ground soon after. This ground rush should be explained and anticipated for the first time night jumper.
Pond swooping is a form of competitive parachuting wherein canopy pilots attempt to touch down and glide across a small body of water, and onto the shore. Events provide lighthearted competition, rating accuracy, speed, distance and style. Points and peer approval are reduced when a participant "chows", or fails to reach shore and sinks into the water. Swoop ponds are not deep enough to drown in under ordinary circumstances, their main danger being from the concussive force of an incorrectly executed maneuver. In order to gain distance, swoopers increase their speed by executing a "hook turn," wherein which both speed and difficulty increase with the angle of the turn. Hook turns are most commonly measured in increments of 90 degrees. As the angle of the turn increases, both horizontal and vertical speed are increased, such that a misjudgement of altitude or imprecise manipulation of the canopy's control structures (front risers, rear risers, and toggles) can lead to a high speed impact with the pond or Earth. Prevention of injury is the main reason why a pond is used for swooping rather than a grass landing area.
With the availability of a rear door aircraft and a large, unpopulated space to jump over, 'stuff' jumps become possible. In these jumps the skydivers jump out with some object. Rubber raft jumps are popular, where the jumpers sit in a rubber raft. Cars, bicycles, motorcycles, vacuum cleaners, water tanks and inflatable companions have also been thrown out the back of an aircraft. At a certain height the jumpers break off from the object and deploy their parachutes, leaving it to smash into the ground at terminal velocity.
A tradition at many drop zones is the swoop and chug. As parachutists from the last load of the day land, other skydivers often hand the landing skydivers a beer that is customarily chugged in the landing area. This is sometimes timed as a friendly competition, but is usually an informal, untimed, kick-off for the night time festivities.
Tracking is where skydivers take a body position to achieve a high forward speed, flying their body to achieve separation from other jumpers and cover distance over the ground.
Using a vertical wind tunnel to simulate free fall has become a discipline of its own and is not only used for training but has its own competitions, teams and figures.
National parachuting associations exist in many countries, many affiliated with the Fédération Aéronautique Internationale (FAI), to promote their sport. In most cases, national representative bodies, as well as local drop zone operators, require that participants carry certification, attesting to their training, their level of experience in the sport, and their proven competence. Anyone who cannot produce such bona-fides is treated as a student, requiring close supervision.
The primary organization in the United States is the United States Parachute Association (USPA). This organization awards licenses and ratings for all American skydiving activities based on safety qualifications. The USPA governs safety in the sport of skydiving as this is the organization's sole responsibility and also publishes the Skydivers Information Manual (SIM) and many other resources. In Canada, the Canadian Sport Parachuting Association is the lead organization. In South Africa the sport is managed by the Parachute Association of South Africa, and in the United Kingdom by the British Parachute Association.
Within the sport, associations promote safety, technical advances, training-and-certification, competition and other interests of their members. Outside their respective communities, they promote their sport to the public, and often intercede with government regulators.
Competitions are organized at regional, national and international levels in most these disciplines. Some of them offer amateur competition.
Many of the more photogenic/videogenic variants also enjoy sponsored events with prize money for the winners.
The majority of jumpers tend to be non-competitive, enjoying the opportunity to "get some air" with their friends on weekends and holidays. The atmosphere of their gatherings is relaxed, sociable and welcoming to newcomers. Party events, called "boogies" are arranged at local, national and international scale, each year, attracting both young jumpers and their elders – Parachutists Over Phorty (POPs), Skydivers Over Sixty (SOS) and even older groups.
In parachuting, a drop zone or DZ is the area above and around a location where a parachutist freefalls and expects to land. It is usually situated beside a small airport, often sharing the facility with other general aviation activities. There is generally a landing area designated for parachute landings. Drop zone staff include the DZO (drop zone operator or owner), manifestors, pilots, instructors, coaches, cameramen, packers, riggers and other general staff.
|This section does not cite any references or sources. (May 2012)|
Costs in the sport are not trivial. As new technological advances or performance enhancements are introduced, they tend to drive equipment prices higher. Similarly, the average skydiver carries more equipment than in earlier years, with safety devices (such as an AAD) contributing a significant portion of the cost.
A full set of brand-new equipment can easily cost as much as a new motorcycle or half a small car. The market is not large enough to permit the steady lowering of prices that is seen with some other equipment like computers.
In many countries, the sport supports a used-equipment market. For beginners that is the preferred way to acquire "gear", and has two advantages because users can:
Novices generally start with parachutes that are large and docile relative to the jumper's body-weight. As they improve in skill and confidence, they can graduate to smaller, faster, more responsive parachutes. An active jumper might change parachute canopies several times in the space of a few years, while retaining his or her first harness/container and peripheral equipment.
Older jumpers, especially those who jump only on weekends in summer, sometimes tend in the other direction, selecting slightly larger, more gentle parachutes that do not demand youthful intensity and reflexes on each jump. They may be adhering to the maxim that: "There are old jumpers and there are bold jumpers, but there are no old, bold jumpers." (Pilots have much the same saying.)
Most parachuting equipment is ruggedly designed and is enjoyed by several owners before being retired. Purchasers are always advised to have any potential purchases examined by a qualified parachute rigger. A rigger is trained to spot signs of damage or misuse. Riggers also keep track of industry product and safety bulletins, and can therefore determine if a piece of equipment is up-to-date and serviceable.
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