BASE jumping grew out of skydiving. BASE jumps are generally made from much lower altitudes than skydives, and a BASE jump takes place in close proximity to the object serving as the jump platform. Because BASE jumps generally entail slower airspeeds than typical skydives (due to the limited altitude), a BASE jumper rarely achieves terminal velocity. Because higher airspeeds enable jumpers more aerodynamic control of their bodies, as well as more positive and quick parachute openings, the longer the delay, the better.
At an altitude of 600m (2,000 feet), having been in free-fall for at least 300m (1,000 feet), the jumper is falling at approximately 55 m/s (190kph, 120 mph), and is approximately 5.7 seconds from the ground. Most BASE jumps are made from less than 600m (2,000 feet). For example, a BASE jump from a 150m (500 foot) object is about 5.6 seconds from the ground if the jumper remains in free fall. On a BASE jump, the parachute must open at about half the airspeed of a similar skydive, and more quickly (in a shorter distance fallen). Standard skydiving parachute systems are not designed for this situation, so BASE jumpers often use specially designed harnesses and parachute containers, with extra large pilot chutes, and many jump with only one parachute, since there would be little time to utilize a reserve parachute. 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 that are rare in normal skydiving (such as "line-over's" and broken lines).
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.[9] (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 (21,670 ft)
