Bungee jumping is an activity that involves jumping from a tall structure while connected to a large elastic cord. The tall structure is usually a fixed object, such as a building, bridge or crane, but it is also possible to jump from a movable object, such as a hot-air-balloon or helicopter, that has the ability to hover above the ground. The thrill comes as much from the free-falling as from the rebounds.
In the 1950s, David Attenborough and a BBC film crew brought back footage of the “land divers” of Pentecost Island in Vanuatu, young men who jumped from tall wooden platforms with vines tied to their ankles as a test of their courage and passage into manhood. A similar practice, only with a much slower pace for falling, has been practised as the Danza de los Voladores de Papantla or the ‘Papantla flyers’ of central Mexico, a tradition dating back to the days of the Aztecs.
The first modern bungee jumps were made on 1 April 1979 from the 250-foot (76 m) Clifton Suspension Bridge in Bristol, by members of the Oxford University Dangerous Sports Club. Commercial bungee jumping began with the New Zealander, A. J. Hackett, who made his first jump from Auckland’s Greenhithe Bridge in 1986.
Guinness only records jumps from fixed objects to guarantee the accuracy of the measurement. John Kockleman however recorded a 2,200-foot (670 m) bungee jump from a hot air balloon in California in 1989. One commercial jump higher than all others is at the Royal Gorge Bridge in Colorado. The height of the platform is 321 metres (1,053 ft). However, this jump is rarely available.
The elastic rope first used in bungee jumping, and still used by many commercial operators, is factory-produced braided shock cord. This consists of many latex strands enclosed in a tough outer cover. The outer cover may be applied when the latex is pre-stressed, so that the cord’s resistance to extension is already significant at the cord’s natural length. This gives a harder, sharper bounce. The braided cover also provides significant durability benefits. Other operators, including A. J. Hackett and most southern-hemisphere operators, use unbraided cords with exposed latex strands (pictured at right). These give a softer, longer bounce and can be home-produced.