Parachuting

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(Redirected from Skydiving)
Skydiver about to land
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Skydiver about to land

Parachuting, or skydiving, is a recreational activity, competitive sport and method of deployment of military personnel (and occasionally, firefighters). It involves the breaking of a free fall from a height through the use of a parachute.

Contents

Procedure

Typically, a trained sky diver (or jumper) and a group of associates meet at an isolated airport. A fixed base operator at that airport usually operates one or more light cargo aircraft, and takes groups of skydivers up for a fee. In the earlier days of the sport, an individual jumper would go up in a Piper Cub aircraft for reasons of economy.

A jump involves individuals jumping out of aircraft (usually an airplane, but sometimes a helicopter or even the gondola of a balloon), usually travelling at approximately 4000 metres (around 12,000 feet) altitude, and free-falling for a period of time before activating a parachute to slow the landing down to safe speeds.

Once the parachute is opened, the jumper can control his or her direction and speed with cords called "steering lines", with hand grips called "toggles" that are attached to the parachute, and so he or she can aim for the landing site and come to a relatively gentle stop in a safe landing environment. Most modern sport parachutes are self-inflating "ram-air" wings that provide control of speed and direction similar to the related paragliders. (Purists in either sport would note that paragliders have much greater lift and range, but that parachutes are designed to absorb the stresses of deployment at terminal velocity.)

4-way formation skydive
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4-way formation skydive

Skydivers skydive because it is the closest one can get to the dream of flying. It is, of course, only an illusion because it is actually more like falling. But skydiving is the only aerial activity where the body is the flying instrument instead of a machine, however simple. Some people explain the attraction to skydiving by adrenaline addiction or suicidal disposition, but these people are usually not skydivers.

Most skydivers make their first jump with an experienced and trained instructor (this type of skydive is called "tandem skydive"). During the jump the jumpmaster is responsible for the stable exit and maintain a proper stable freefall position, activating and controlling the parachute. With training and experience, the fear of the first few jumps fades, to be supplanted by the satisfaction of mastering aerial skills and performing increasingly complicated maneuvers in the sky with friends. Other training methods include static line, IAD, and AFF -- see below.

Skills

Parachuting has complex skills that can take thousands of jumps to master but the basics are often fully understood and useful during the first few jumps. There are four basic areas of skill: basic safety, free fall maneuvers, parachute operation, and landing.

Basic safety includes knowing how and when to do a gear check, exit normally and in an emergency, deploy a parachute, handle common malfunctions, pick a landing area and setup and execute a landing. Most national sport organizations certify instructors, most operators who fly skydivers retain an instructor, and all certified instructors can teach the basics well enough for a student to be licensed by the national sport organization.

In freefall most skydivers start by learning to maintain a stable belly to earth "box" position. In this position the average fallrate is around 125 mph. Learning a stable box position is a basic skill essential for a reliable parachute deployment. Next jumpers learn to move or turn in any direction while remaining belly to earth. Using these skills a group of jumpers can create sequences of formations on a single jump, a discipline known as relative work (RW). In the late 1980s more experienced jumpers started experimenting with freeflying, falling in any orientation other than belly to earth. Today many jumpers start freeflying soon after they earn their license, passing the RW stepping stone.

Choosing when to deploy the parachute is a matter of safety. A parachute should be deployed high enough to give the parachutist time to handle a malfunction should one occur. Two thousand feet is the practical minimum for advanced skydivers. In freefall, skydivers monitor their altitude meters to decide when to break off from the formation (if applicable) and when to open their parachutes. Many skydivers open higher to practice flying their parachute; on a "hop-and-pop," a jump in which the parachute is immediately deployed upon exiting the aircraft, it is not uncommon for a skydiver to be under canopy as high as 4000 or 5000 feet.

Flying the parachute has two basic challenges: 1. To land where you planned, often on a target. 2. To avoid injury. On a more advanced note, some skydivers enjoy performing aerobatic maneuvers with parachutes.

Modern parachutes are wings "canopy", and can glide substantial distances. Elliptical canopies go faster and farther, and some small, highly loaded canopies glide faster than a man can run, which can make them very challenging to land. Highly experienced skydiver using very small canopy can achieve over 60 mph vertical speeds in landing.

A good landing will not have any discomfort at all, and will land the skydiver within a few feet of his intended location. Champion accuracy skydivers routinely land less than 2 inch from the center of a target even in competitions.

Nowdays most of the skydiving related injuries happen under a fully opened and functioning parachute, the most commont reasons of these injuries are badly-executed, radical maneuver near to the ground, like quick turns, too low or too high landing flare.

Safety

Despite the seeming danger of the leap, fatalities are rare. In the US and in most of the western world skydivers are required to carry a second, reserve parachute which has been inspected and packed by an FAA certified parachute rigger, and many now use an altitude-sensitive automatic activation device (AAD) that activates the reserve parachute at a safe altitude if the skydiver somehow fails to activate the chute on their own. They also routinely carry both visual and audible altimeters to help maintain altitude awareness.

It should be emphasized that many of today's active parachutists have jumped for decades without significant injury. Injuries, when they do occur, are usually caused by inattention or improper action on the part of the parachutist. Some involve the parachute getting tangled up and thus not providing the full deceleration. These are very rare. Others arise from changes in wind forcing hard landings -- again, very rare. In recent years, one of the most common sources of injury is the inexperienced or overconfident (mis)use of perfectly good, high-performance parachutes to effect crowd-pleasing landings. High-speed maneuvers performed very close to the ground can be exhilarating to perform, and exciting to watch, but they necessarily increase the risk.

Each year, a number of people are hurt or killed in parachuting, world-wide. (see fatality statistics (http://www.skydivingfatalities.info/), or the newer dropzone.com statistics (http://www.dropzone.com/fatalities/)) The fundamental nature of the sport might suggest why that is so. On the other hand, statistics suggest that, with due care and attention (not to mention sound training and a good attitude) the more likely outcome is that hundreds of thousands of people make millions of jumps, and go back to do it again. A particularly telling point might be the increasing numbers of sport parachutists who have each logged well over 10,000 jumps in their respective careers.

Inexperienced skydivers are a substantial hazard in the air. For the first few jumps, many beginners choose to jump in a linked harness, with an instructor in the other harness. Even newly-licensed skydivers sometimes are shunned by groups until they've completed fifty to a hundred jumps, and their experience is personally known to a number of people on the field. For many skydivers this is not nastiness, or elitism, but a simple desire not to have anything broken.

It is worth noting that what is depicted in commercial films -- notably Hollywood action movies -- usually exaggerates the dangerous-looking aspects of the sport. Often, the characters in such films are depicted 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.

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

Types of Parachuting

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Static_jump.jpg
Static parachute jump (combat practice) from very low altitude in groups of three

Once individuals have mastered the basic jump, there are several different disciplines to embrace within parachuting. Each of these is enjoyed by both the recreational (weekend) and the competitive participants. There is even a small group of professionals who earn their living with parachuting. They win competitions having cash prizes or are employed or sponsored by skydiving related manufacturers.

Parachutists can participate both in competitive and in purely recreational skydiving events. World championships are held regularly in locations offering flat terrain and clear skies. An exception is Paraski, where winter weather and ski-hill terrain are required.

Types of parachuting include:

Training

There are ways to practice different aspects of skydiving, without actually jumping. Wind tunnels can be used to practice skills for free fall, while virtual reality skydiving simulators can be used to practice parachute control.

Beginning skydivers seeking training have a few different options available to them: tandem, static line, IAD, and AFF.

Tandem

Tandem jumps are perhaps the most common type of jump selected by first-time skydivers. The jump is usually done from 10000+ feet, and often as high as 14000 feet above ground level. As mentioned earlier, the jumper is strapped to the front of an experienced jumper, known as the "tandem master." This method is popular with those who only want to make one skydive, since it requires relatively little training for the student. If desired, though, someone who starts off with a tandem jump can progress into student training to become an experienced jumper.

Static line

In a static line jump, the student exits the plane on their own, and their parachute is opened right away by a static line attached to the aircraft (hence the name). The jump is usually done from around 3500-4000 feet, and the student is in constant radio contact with somebody on the ground on the way down. If the student desires to keep training using this method, static line progression gradually introduces freefall on the later jumps.

IAD

Instructor Assisted Deployment, or IAD for short, is a variant of static line. The main difference is that instead of being deployed by a static line, the student's jumpmaster (who is in the plane with them) deploys the parachute themselves by throwing the pilot chute out the door as the student exits.

AFF

Accelerated Freefall -- AFF -- is a method of training preferred by many for those students who are serious about wanting to become skydivers. The "accelerated" comes from the fact that instead of building up the amount of freefall the student is exposed to, the student exits at maximum altitude (12k-14k feet) starting with the first jump. Instructors jump with the student during AFF jumps, and as they freefall with the student, they are able to monitor and correct the student's body position and other problems during freefall. Later exercises include things such as turns, backflips, and being able to dock. During the first several AFF jumps, as with the other training methods, the student has radio contact with ground personnel while they are under canopy.

Other Fun Stuff

In addition to the various "disciplines", for which people actually train and purchase specialized equipment and get coaching, the recreational skydiver finds ways to just have fun.

Hit and Rock

One example is "Hit and Rock", which is a variant of Accuracy parachuting devised to let people of varying skill-levels "compete" for fun, while spoofing the age and abilities of some participants. It is a good way to have fun on days when the cloud-cover is high enough to be legally jumpable, but too low for meaningful freefall.

In classic accuracy, the parachutist exits at 800 meters, flies a big, boxy, purpose-built parachute toward a dinner-plate sized target with a 3-centimeter dot in the middle. Near the ground, the parachutist aligns above the target and then sinks elevator-style until the target can be poked with a heel. The target has electronic sensors that show the precise distance of that heel-strike from target center.

In swoop accuracy, the parachutist exits at whatever altitude, flies a zippy, high-aspect-ratio wing to the vicinity of the target, then executes a diving turn that levels out into a long, high-speed swoop, close over the ground. At some point in that swoop, the parachutist (... excuse me, "canopy pilot") passes over the target and attempts to stab it with a foot on the way by.

Both of those styles involve considerable skill, such that junior parachutists would have little hope against people with years of experience. So, to add some fun and frivolity, the target is replaced by a rocking chair.

The object now becomes: to land as close as possible to the chair, doff 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.

Hit and Chug

Very similar to Hit and Rock, except the target is replaced by a crate of beer bottles with screwtop caps. Contestant is timed from the moment that feet touch the ground until the contestant drinks a bottle of beer and places the empty bottle upside-down on head.

Cross-Country

Some days, the winds at ground level might be acceptable (barely) for safe landings, but the winds aloft are blowing strongly, such that parachutists must fly some distance upwind in order to arrive back at the intended landing area.

That is, if they opened their parachutes directly over the dropzone, the forward speed of the wings would be insufficient to counter the wind, and they'd find themselves backing up, until the wind abated near the ground. In those conditions, somebody sometimes suggests a "cross-country" jump. Let's purposely go a long distance away, exit at relatively high altitude, open our parachutes immediately, and see if we can glide all the way back.

Participants dress comfortably and pack a lunch, a cell-phone or change for payphone, and perhaps two-way radios if those are available. The group examines local maps if needed and, considering the wind conditions at various altitudes, determines a distant exit point from which they think they can fly all the way back to the dropzone. The idea is to choose an exit point such that everybody should get back, but those who find themselves unable to get back will be able to find a safe area in which to land.

Those who are most skilled at getting the maximum horizontal glide from their parachutes can arrive back at the dropzone with just a little altitude to spare -- if the exit point was properly chosen. Those with less skill, or those who have misjudged the glide-ratio of their equipment get to walk at least part of the distance, or beg a ride. Two-way radios can allow the participants to chat with each other -- or heckle each other when somebody begins to fall behind. The radios or cell-phones aid in the recovery effort when friends finally relent and drive out to retrieve those who overestimated their abilities.

A wise choice of off-site landing, combined with an ingratiating manner has netted some "cross-country" participants a nice free lunch from a friendly farm family. A poor choice has netted some participants an encounter with a bull, a tree, a swamp, or a freshly-manured field. Either way, a cross-country jump usually yields a few stories to tell around future bonfires.

Tracking jump

Tracking is assuming a body position that maximizes horizontal speed while minimising vertical speed. It is most commonly used at the end of freefall to gain enough separation from other skydivers for a safe deployment.

A tracking dive is a skydive where the intention is to track for the entire duration of freefall. One person, usually the most experienced tracker, is designated the leader (or rabbit). The rabbit directs the direction of the group and maintains the groups tracking speed. Other participants chase the rabbit and try to maintain a relative position.


Camera Flying

In camera flying, a cameraman jumps with a group and films them. The cameraman has specialized equipment, such as wings and a head-mounted camera. Some skydivers specialize in this, and make a fair amount of money filming students and first-time jumpers.

Night Jumps

Skydiving is not always restricted to daytime hours. Experienced skydivers sometimes perform night jumps. For obvious safety reasons, this requires more equipment than a usual daytime jump. A lighted altimeter (or an audible altimeter) is a must. Skydivers performing night jumps often take flashlights up with them so that they can check their canopies once they deploy, so they can be assured that the canopy has opened correctly and is safe to land. 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 in every direction, and to turn it on once they are under canopy.


Parachuting organizations

National parachuting associations exist in many countries (many affiliated with the Fdration Aronautique Internationale (FAI)), to promote their sport. In most cases, national representative bodies, as well as prudent local dropzone 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.

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 the enthusiatic young jumpers and many of their elders -- Parachutists Over Phorty (POPs), Skydivers Over Sixty (SOS) and even older groups who have yet to choose a catchy name for themselves.

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Two-Skydiving.jpg
A tandem instructor and a student skydiving together

Commercial parachuting services vs. parachuting clubs

At larger centers, mostly in "sun-belt" locations, training in the sport is often conducted by professional instructors and coaches at commercial establishments. The advantages to the newcomer are year-round availability, larger aircraft (which translates to greater comfort, higher jump altitudes, and more frequent jumping), and staff who are very current in both their sport and their instructional skills. It is also common for instructors and newcomers to jump while strapped together (see picture). For the newcomer, this gives an added measure of safety should something go wrong.

In the other latitudes, where winter (or monsoon) gets in the way of year-round operation, commercial skydiving centers are less prevalent and much of the parachuting activity is carried on by clubs. Most clubs cannot support larger aircraft. Training may be offered (by volunteer instructors who, nevertheless, are rigorously tested and certified) only in occasional classes as demand warrants. The entire experience tends to be informal and surrounded by a lot of socializing.

Some observers have suggested that commercial operations cater to a "fast-food" sensibility that leaves their novice graduates with very compartmentalized skill sets that may be lacking in important peripheral areas. This is countered by the observation that students at busy commercial operations receive concentrated exposure and experience, and are thus able to improve rapidly without backtracking or developing bad habits.

The observation about participants who started learning in the club setting is that their progression can be slower due to smaller aircraft and fewer "good jumping days" (weather). They may experience some backsliding as they need to re-learn some skills after weather-enforced lay-offs. By contrast, the progression of a novice in a club usually involves learning all the ancillary skills out of necessity. Everyone at a club learns all the skills and takes on all the roles.

For example, a large aircraft must be "spotted" (directed to fly over the optimum exit point) by an experienced jumper who is usually a parachute-center staffer. Having experienced staff perform this duty ensures that everybody leaves the aircraft within range of the landing zone. Nobody needs to hike or take a taxi back to the dropzone because their jumprun was spotted by a novice. The downside is that the novices never learn the skill of reading the winds, the terrain and the aircraft movement, and of directing the aircraft where it should go. They remain dependent on the "pro."

At clubs, the aircraft are smaller, and everybody is a friend. A bad spot is an excuse for some teasing, but it doesn't interrupt the smooth flow of a moneymaking operation. Therefore, most people who join parachuting clubs are taught spotting skills very early in their careers. Similar contrasts apply to parachute packing, equipment maintenance and other skills of a well-rounded skydiver.

The answer to both sets of critics is that they are correct as far as they go. The perceived shortcomings of each learning environment are ameliorated by the fact that most skydivers eventually partake of both settings. Club members often visit larger centers for holidays and events and for some concentrated exposure to the latest techniques. People who learned at commercial centers often make friends with visiting club jumpers and then visit them at their home dropzones -- or start their own clubs.

Equipment

Costs in the sport are not trivial. As new technological advances or performance enhancements are introduced, they tend to nudge equipment prices higher. Similarly, the average skydiver carries more equipment than in earlier years, with safety devices (such as an automatic reserve activation device) 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 commoditization and price-erosion that is seen in other technologically intensive industries (like the computer industry).

In many countries, the sport supports a substantial used-equipment market. For many beginners, especially those with limited funds, that is the preferred way to acquire "gear", and has two advantages:

  • First, they can try different types of parachutes (there are many) to learn which style they prefer, before paying the price for new equipment.
  • Second, they can acquire a complete system and all the peripheral items in a short time and at reduced cost.

Novices generally start with parachutes that are large and docile relative to the jumper's body-weight. As they improve in skill and confidence, it is customary to 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."

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.

See also

drop zone, parachute

External links

  • Dropzone.com (http://www.dropzone.com) the Premier web resource for information on Skydiving, Dropzones and modern parachuting
  • USPA (http://www.uspa.org) The United States Parachute Association -- The governing body for sport skydiving in the U.S.
  • Free Charity Skydiving and Parachuting (http://www.getkidsgoing.com/parachute_skydiving_skydive.htm) Experience skydiving, parachuting and tandem jumps across the UK by raising money for disabled children.
  • Extreme Sports Cafe (http://www.extremesportscafe.com) - Advice on all aspects of Extreme Sports, especially Skydiving.
  • Extreme Sports (http://www.adventuresportsholidays.com)
  • [1] (http://www.aero.com/publications/parachutes/9511/pc1195.htm)- A brief website about the history and the etomology of the parachute
  • [2] (http://inventors.about.com/library/inventors/blparachute.htm)- History, Design, and Information about parachutes.

Notes

Malone, Jo (June, 2000). Birth of Freefly (http://www.bpa.org.uk/skydive/pages/articles/jun00/birthoffreefly.htm). Skydive the Mag.de:Fallschirmspringen es:Paracaidismo fr:Parachutisme he:צניחה חופשית ja:スカイダイビング nl:Parachutespringen pl:Spadochroniarstwo pt:Paraquedismo ru:Парашютизм

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