If you think that sky diving is one of the scariest in extreme sports, you should try base jumping. BASE jumping essentially came from skydiving. Instead of jumping out of an airplane, the BASE jumper jumps off of fixed objects such as buildings, cliffs, or towers. The other difference is that the base jumper has to jump not only out but down. When you jump from a plane you leave the plane in a downward motion until you hit the ground. The BASE jumper has to jump out several feet because they are falling very close to the building or tower they have just jumped from.
The BASE jumper will fall at a slower rate of speed than the skydiver because there is not enough altitude for the falling diver to get up to speed. The extreme sports enthusiast who base jumps will pick a high enough platform to get the thrill of free falling and still have enough time for the parachute to open and slow his descent. If the BASE jumper exceeds the twelve seconds it takes to achieve terminal velocity in the fall it will match the speed of the sky diver. In base jumping this rarely happens.
The skydiver uses the air currents and the flow around their body to stabilize their body during descent. On the other hand the BASE jumper made twist in the air because the descent is not long enough for them to stabilize. The twisting and tumbling in the air is one of the things that make these one of the most dangerous of extreme sports. The parachute is usually opened just after jumping or shortly thereafter. If the jumper is tumbling because of a bad take off, the parachute may open poorly which could cause the jumper to be entangled in the cords or the chute itself.
The shortness of the jump does not allow the jumper to use the traditional parachute. He or she must use a smaller parachute with a larger pilot or starting chute that will pull the large parachute out of the harness. The harness is specified for the jumper so that it is lighter weight. The BASE jumper does not have a reserve parachute, because there is not enough time to deploy it. The reserve parachute would be cumbersome and add more tumbles on the way down. This would add another element of danger to the jump.
There is more danger for the extreme sports enthusiast who tries this sport. Not only is the fall dangerous, but so is the landing. The BASE jumper has little area in which to land. Because the base is a standing structure, a high wind or wind shift can cause the jumper to slam into the structure they are jumping from. If they are jumping from a cliff, the bottom might be strewn with boulder, trees, or rocks. If the BASE jumpers are jumping from a bridge or trestle, the only place to land is on the small beach beside a river or in the river itself.