Base Jumping



BASE jumping grew out of skydiving (recreational parachuting from aircraft). There are three main technical differences between the two. First, BASE jumps are generally made from much lower altitudes than skydives. Second, a BASE jump takes place in close proximity to the cliff or tower which provided the jump platform. Third, the BASE jumper generally has a lower airspeed than a skydiver throughout the jump, because a BASE jump starts with zero airspeed, and (due to the limited altitude) a BASE jumper very seldom approaches the terminal velocity (airspeed) of a skydiver. All three factors have significant implications.

First, the BASE parachute system has to be made to open very quickly at low airspeeds. Skydiving parachutes are reefed to slow down the opening and reduce opening shock forces. Second, the cliff or tower presents a risk to the BASE jumper if, for example, the parachute opens facing backwards. An off-heading opening is not considered a problem in skydiving, but has caused fatal impact injuries in BASE jumping. Off heading opening resulting in object strike is the leading cause of serious injury and death in BASE jumping.

An experienced skydiver is recommended to deploy their parachute no lower than 2,000 feet (610 m). At that time, if they have already been in free-fall for at least 1,000 feet (305 m), the jumper is traveling 120 miles per hour (54 m/s), and is 11 seconds from the ground. Most BASE jumps are made from less than 2,000 feet (610 m). For example, a BASE jump from a 500 foot (152 m) object is about 5.6 seconds from the ground if the jumper remains in freefall. On such a jump, the parachute must open at about half the airspeed of the skydiver, and more quickly (ie. in a shorter distance fallen). Standard skydiving parachute systems are not designed for this situation. Many BASE jumpers use specially designed harnesses and parachute containers, with extra large pilot chutes, and jump with only one parachute - since, with a total freefall time of 5.6 seconds, there would be no time to use a reserve parachute. In these systems, the actual parachute canopy should also be specifically manufactured for BASE jumping, however skydiving parachutes with some modifications (primarily the addition of a tail pocket for stowing suspension lines) are occasionally used by those unable to purchase appropriate equipment. The rest of the system is almost always specifically designed for BASE use. Standard skydiving equipment can only be used on relatively high BASE jumps. If modified, by removing the bag and slider, stowing the lines in a tail pocket, and fitting a large pilot chute, standard skydiving gear can be used for lower BASE jumps, but is then prone to kinds of malfunction which are rare in normal skydiving (such as "line-overs" and broken lines).

The vast majority of people who try BASE jumping are those that have already learned to skydive. It is important to know how to safely fly and land a parachute, and this is best learned on airplane skydives, from higher deployment altitudes, over large fields that provide room for error in learning how to land. Most BASE jumping venues have very small areas in which to land. A beginner skydiver, after parachute deployment, may have 3 minutes or more of a parachute ride to the ground. A BASE jump from 500 feet (152 m) will have a parachute ride of about 10 to 15 seconds.

One way to make a parachute open very quickly is to use a static line or direct bag. These devices form an attachment between the parachute and the jump platform, which stretches out the parachute and suspension lines as the jumper falls, before separating and allowing the parachute to inflate. This method enables the very lowest jumps (below 200 ft) to be made, although most BASE jumpers are more motivated to make higher jumps involving free fall.

In parachuting, height is safety, and by making lower altitude jumps, BASE jumpers give up the safety margins built into skydiving (such as the option of using a reserve parachute if there are problems deploying the main chute). The lower airspeed of a BASE jump is also a risk factor. Skydivers use the air flow to stabilise their position, allowing the parachute to deploy cleanly. BASE jumpers, falling at lower speeds, have less aerodynamic control, and may tumble. Usually BASE jumpers jump to cause a tumble by back flipping and then using the gyroscopic effects to at least have some form of control. The attitude of the body at the moment of jumping determines the stability of flight in the first few seconds, before sufficient airspeed has built up to enable aerodynamic stability. On low BASE jumps, parachute deployment takes place during this early phase of flight, so if a poor "exit" leads into a tumble, the jumper may not be able to correct this before the opening. If the parachute is deployed while the jumper is tumbling, there is a high risk of entanglement or malfunction. Beginner BASE jumpers often make the error of rotating forwards by jumping with a swimming-pool type of diving motion, leading to an involuntary forward loop. Better technique is to exit without any rotational motion.

On higher BASE jumps, those which allow a free fall of five seconds or more, it may be necessary to use freefall tracking technique to move away from the jump object (especially on cliff jumps). Jump platforms providing an overhang, such as arch bridges or naturally overhung cliffs, are more forgiving in this respect and so are more suitable for beginner BASE jumpers.

In the United States, skydiving from an airplane involves regulations set by the FAA, notably the requirement of an airplane jumper to carry two parachutes. Since BASE jumping does not involve an airplane, the FAA has no jurisdiction.

The legal issues that a BASE jumper must consider concern permissions to use the object that is being jumped, and the area used for landing.

Covert BASE jumps are often made from tall buildings and antenna towers. The general reluctance of the owners of these objects to allow their object to be used as a platform leads many BASE jumpers to covertly attempt jumps. While BASE jumping itself is not illegal, the covert nature of accessing objects usually necessitates trespassing on an object. Jumpers who are caught can expect to be charged with trespassing, as well as having other charges like breaking and entering, reckless endangerment, vandalism, or other such charges pressed against them. Other people accompanying the jumper, such as ground crew, may also face charges.

In some jurisdictions it may be permissible to use land until specifically told not to. Perrine Bridge in Twin Falls, Idaho, is the only manmade structure in the United States where BASE jumping is allowed year-round without a permit.

Once a year, on the third Saturday in October ('Bridge Day') at the New River Gorge Bridge in Fayetteville, West Virginia, permission to BASE jump has explicitly been granted. The New River Gorge Bridge deck is 876 feet (267 m) above the river. A rock dropped from the deck will hit the water in 8.8 seconds. This annual event attracts about 450 BASE jumpers, and nearly 200,000 spectators. If the conditions are good, in the 6 hours that it is legal, there may be over 800 jumps at Bridge Day. For many skydivers who would like to try BASE jumping, this will be the only fixed object from which they ever jump.

However the National Park Service has the authority to ban specific activities in US National Parks, and has done so for BASE jumping. The authority comes from 36 CFR 2.17(3), which prohibits, "Delivering or retrieving a person or object by parachute, helicopter, or other airborne means, except in emergencies involving public safety or serious property loss, or pursuant to the terms and conditions of a permit." Under that Regulation, BASE is not banned, but is allowable if a permit is issued by the Superintendent, which means that a mechanism to allow BASE in National Parks was always in place. However, National Park Service Management Policies have stated that BASE "is not an appropriate public use activity within national park areas..." (2001 Management Policy 8.2.2.7.) This meant that there could be no permitted air delivery. It is noted, however, that this policy has a proposed change that strikes the language banning it outright and replacing it with a different test. Whether this will be approved, and whether this will make the granting of permits easier, is open to speculation.

In the early days of BASE jumping, the Service ran a permit scheme under which jumpers could get authorisation to jump El Capitan. This scheme ran for 3 months in 1980 and then collapsed amid allegations of abuse by unauthorised jumpers. Since then, the Service has vigorously enforced the ban, charging jumpers with "aerial delivery into a National Park". One jumper was drowned in the Merced river while being chased by Park Rangers intent on arresting him. Despite this, illegal jumps continue in Yosemite at a rate estimated at a few hundred per year, often at night or dawn. El Capitan, Half Dome and Glacier Point are all used as jump sites.

Other US public land, including land controlled by the Bureau of Land Management, does not ban air delivery, and there are numerous jumpable objects on BLM land.

The legal position is better at other sites and in other countries. For example, in Norway's Lysefjord, BASE jumpers are made welcome. Many sites in the European Alps, near Chamonix and on the Eiger, are also open to jumpers.

BASE jumping has its own unique set of ethical guidelines which have been evolving over time. The underlying motivation for BASE ethics is a shared desire to jump, and to do so while avoiding arrest or injury. The bottom line aim of BASE ethics is to allow jumpers to continue making as many jumps as possible in the long run. It follows then, that actions which make it harder for others to jump are generally viewed as unethical, to some varying degree.

The nuances of BASE ethics vary from place to place, and especially depending on the legal status of a site. Sometimes there are established guidelines for a site such as at an increasing number of popular legal sites. The guidelines usually have been established for good reasons, and often in conjunction with local authorities. Jumpers breaking these rules, through ignorance or otherwise, undermine the legalization efforts of the entire BASE community.

The guiding principle of BASE ethics is respect. BASE jumpers should respect the sport, the sites, and other people whether jumpers or non-jumpers.

Failing to respect the serious nature of BASE will quickly alienate many experienced jumpers, who have learned to respect BASE through hard personal experiences. Lack of respect for the sport can be shown in many ways. Dismissing the inherent dangers of the sport is one. Putting unprepared people off for a "BASE thrill ride" is another. Instructing students who lack appropriate preparation is a third. The bottom line is that BASE can, like many extreme sports, turn deadly serious in a heartbeat.

Failing to respect sites, and the guidelines for jumping them be they formal or not, will almost certainly anger jumpers who established, and continue to jump, those sites. Site guidelines and procedures vary from simple ("don’t land by the farmhouse"), to Byzantine ("drive up the left side of the dirt road, park behind the loading dock, and keep your lights on until you reach the third door"), to downright bizarre. Respecting other people is especially more important in BASE. Jumpers depend on each other for instruction, assistance and mutual aid. While this is most obvious in simple things, like carpooling to a jump site, it also applies to opening and maintaining site access, avoiding arrest, and providing medical assistance to injured jumpers. In the most extreme, jumpers rely on each other for emotional support when tragedy occurs. While they sometimes like to think of themselves as rugged individualists, in the end, BASE is a team sport.

BASE ethics also demand that jumpers should also respect the non-jumping people who live or work around BASE sites. Many jumpers travel to jump, and it is important to understand and respect the culture and wishes of the local people. There are some popular cliffs in Europe, for example, where jumpers are asked to land in specific areas so as not to disrupt local agriculture. The popular legal span in the western US is located in a small, conservative, rural community, which has little tolerance for public nudity or profanity. Understanding and respecting the culture of local residents helps protect site access, as well as conveying a positive image of BASE jumpers to the general public.

When a jumper completes a jump from each of the four categories of objects, they may choose to apply for a "BASE number". These are awarded sequentially. In 1981, Phil Smith of Houston, Texas, was awarded BASE-1. In March 2005 the 1000th application for a BASE number had been filed.

BASE jumping is often featured in action movies, like the 2002 Vin Diesel film xXx where Diesel's character catapults himself off a bridge in an open-topped car, landing safely as the car crashes on the ground. After the 1976 Mount Asgard jump featured in the pre-credits sequence to The Spy Who Loved Me, the James Bond movies continued to feature 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, though, only the Mt Asgard and Eiffel Tower jumps were filmed in reality; the rest were special effects.

The 1990s surge of interest in extreme sports saw many developments in BASE jumping and increasing acceptance of it generally, though it is still widely seen as a daredevil stunt rather than a sport. Even though it is a highly skilled activity, the lack of an objective way to measure skill as the basis for records and competitions, hinders acceptance as a true sport; and it remains as dangerous as it looks, prompting some, with typically black humor, to say that BASE stands for "Bones And Shit Everywhere". Through the availability of specialised equipment and wider knowledge of techniques, it is safer today than in the early days, though the occasional fatalities and injuries occur. Some deaths through ground impact in freefall or object strike do occur, but most incidents are due to hazardous landing sites or other problems which develop after the parachute has opened. Because of the covert nature of much of BASE jumping, no reliable figures are available to assess the statistical risks of the activity.

he Guinness Book of 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 Nic Feteris and Glenn Singleman with a jump from the 19,000 ft Trango cliff in Pakistan. However, Singleman and partner Heather Swan claimed a new record for highest starting elevation on 23 May 2006 by jumping from Meru Peak in northern India at an elevation of 6,604 metres (21,667 ft).

The sheer variety of the nature of the challenge at different jump sites means that direct comparisons of different jumps are often meaningless. As a result, some of the claimed records in the field may seem spurious. There is another Guinness entry for "oldest BASE jumper" which is clearly nothing to do with sporting skill. Even more contentious are claims sometimes made (although not recognised by Guinness) for the lowest jump. Given that a static-lined parachute can be made to open in little more than the length of its suspension lines, jumps can actually be performed at practically any altitude right down to the point at which a parachute is not necessary for survival.

BASE competitions have been held since the early 1980s, with accurate landings or freefall aerobatics used as the judging criteria. Recent years have seen a formal competition held at the 1300 ft Petronas Towers building in Malaysia, judged on landing accuracy. While BASE jumping is a long way from being an Olympic sport, an increasing number of BASE devotees take their sport seriously as a skilled athletic pursuit. It is moving steadily towards the crossover point at which it will be taken seriously by everyone, as a minority, but genuine, sport.

For now, BASE jumpers are mostly focused on the challenges of public acceptance and understanding of a sport so obviously extreme and so highly dangerous; and on the development of equipment and techniques. Searching for new, and preferably legal, jump sites has also been a fruitful activity for many devotees.

Inquiries about sites serve as the primary gatekeeper of the BASE community. If a prospective jumper has to locate experienced jumpers to learn about sites, there is a far greater chance that they will receive instruction (of any kind) and use appropriate gear. If a site is publicized, pretty much anyone can run out and throw himself off of it. He can jump with no training, with improper equipment and with no supervision. This is a recipe for disaster, and has resulted in multiple accidents, including more than one fatality.

Any discussion of a site can easily be held by referring to the site descriptively, rather than by name or location. It is easy to discuss "the Bridge Day site" or "the popular terminal wall in Northern Italy" for example, and using such labels detracts nothing from a technical discussion.

Accidents occur at legal sites, as well as illegal ones, and this reasoning applies equally to either. In fact, the majority of BASE fatalities have occurred at legal sites. The ease of access to these sites, as well as the frequency of accidents, argues, if anything, for greater site secrecy at legal sites.

Some BASE jumpers feel that preventing accidents is important because it keeps sites open for jumping (whether legal or illegal). This concern is a distant second to preventing injury.Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts.
Virtual Magic is a human knowledge database blog. Text Based On Information From Wikipedia, Under The GNU Free Documentation License. Copyright (c) 2007 Virtual Magic. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts and no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".

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