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| safety in parachuting |
Despite the perception of danger, fatalities are rare. However, each year a number of people are hurt or killed parachuting worldwide. About 30 skydivers are killed each year in the US, roughly one death for every 100,000 jumps (about 0.001%).
In the US and in most of the western world skydivers are required to carry two parachutes. The reserve parachute must be periodically inspected and re-packed (whether used or not) by a certificated parachute rigger (in the US, an FAA certificated parachute rigger). Many skydivers use an automatic activation device (AAD) that opens the reserve parachute at a safe altitude in the event of failing to activate the main canopy themselves. Most skydivers wear a visual altimeter, and an increasing number also use audible altimeters fitted to their helmet.
Injuries and fatalities occurring under a fully functional parachute usually happen because the skydiver performed unsafe maneuvers or made an error in judgment while flying their canopy, typically resulting in a high speed impact with the ground or other hazards on the ground. One of the most common sources of injury is a low turn under a high-performance canopy and while swooping. Swooping is the advanced discipline of gliding parallel to the ground during landing.
Changing wind conditions are another risk factor. In conditions of strong winds, and turbulence during hot days the parachutist can be caught in downdrafts close to the ground. Shifting winds can cause a crosswind or downwind landing which have a higher high potential for injury due to the wind speed adding to the landing speed.
Another risk factor is that of "canopy collisions", or collisions between two or more skydivers under fully inflated parachutes. Canopy collisions can cause the jumpers' inflated parachutes to entangle with each other, often resulting in a sudden collapse (deflation) of one or more of the involved parachutes. When this occurs, the jumpers often must quickly perform emergency procedures (if there is sufficient altitude to do so) to "cut-away" (jettison) from their main canopies and deploy their reserve canopies. Canopy collisions are particularly dangerous when occurring at altitudes too low to allow the jumpers adequate time to safely jettison their main parachutes and fully deploy their reserve parachutes.
Equipment failure rarely causes fatalities and injuries. Approximately one in 750 deployments of a main parachute results in a malfunction. Ram-air parachutes typically spin uncontrollably when malfunctioned, and must be jettisoned before deploying the reserve parachute. Reserve parachutes are packed and deployed differently; they are also designed more conservatively and built and tested to more exacting standards so they are more reliable than main parachutes, but the real safety advantage comes from the probability of an unlikely main malfunction multiplied by the even less likely probability of a reserve malfunction. This yields an even smaller probability of a double malfunction although the possibility of a main malfunction that cannot be cutaway causing a reserve malfunction is a very real risk.
Parachuting disciplines such as BASE jumping or those that involve equipment such as wing suit flying and sky surfing have a higher risk factor due to the lower mobility of the jumper and the greater risk of entanglement. For this reason these disciplines are generally practiced by experienced jumpers.
Depictions in commercial films — notably Hollywood action movies — usually overstate the dangers of the sport. Often, the characters in such films are shown 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. USPA member drop zones in the US and Canada are required to have an experienced jumper act as a "safety officer" (in Canada DSO – Drop Zone Safety Officer; in the U.S. S&TA – Safety and Training Advisor) who is responsible for dealing with the jumpers who violate rules, regulations, or otherwise act in a fashion deemed unsafe by the appointed individual.
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.
Parachuting and weather
Parachuting in poor weather, especially with thunderstorms, high winds, and dust devils can be a dangerous activity. Reputable drop zones will suspend normal operations during inclement weather.
Canopy Collisions
A collision with another canopy is a statistical hazard, and may be avoided by observing simple principles.
Source: http://en.wikipedia.org/wiki/Parachuting
In the US and in most of the western world skydivers are required to carry two parachutes. The reserve parachute must be periodically inspected and re-packed (whether used or not) by a certificated parachute rigger (in the US, an FAA certificated parachute rigger). Many skydivers use an automatic activation device (AAD) that opens the reserve parachute at a safe altitude in the event of failing to activate the main canopy themselves. Most skydivers wear a visual altimeter, and an increasing number also use audible altimeters fitted to their helmet.
Injuries and fatalities occurring under a fully functional parachute usually happen because the skydiver performed unsafe maneuvers or made an error in judgment while flying their canopy, typically resulting in a high speed impact with the ground or other hazards on the ground. One of the most common sources of injury is a low turn under a high-performance canopy and while swooping. Swooping is the advanced discipline of gliding parallel to the ground during landing.
Changing wind conditions are another risk factor. In conditions of strong winds, and turbulence during hot days the parachutist can be caught in downdrafts close to the ground. Shifting winds can cause a crosswind or downwind landing which have a higher high potential for injury due to the wind speed adding to the landing speed.
Another risk factor is that of "canopy collisions", or collisions between two or more skydivers under fully inflated parachutes. Canopy collisions can cause the jumpers' inflated parachutes to entangle with each other, often resulting in a sudden collapse (deflation) of one or more of the involved parachutes. When this occurs, the jumpers often must quickly perform emergency procedures (if there is sufficient altitude to do so) to "cut-away" (jettison) from their main canopies and deploy their reserve canopies. Canopy collisions are particularly dangerous when occurring at altitudes too low to allow the jumpers adequate time to safely jettison their main parachutes and fully deploy their reserve parachutes.
Equipment failure rarely causes fatalities and injuries. Approximately one in 750 deployments of a main parachute results in a malfunction. Ram-air parachutes typically spin uncontrollably when malfunctioned, and must be jettisoned before deploying the reserve parachute. Reserve parachutes are packed and deployed differently; they are also designed more conservatively and built and tested to more exacting standards so they are more reliable than main parachutes, but the real safety advantage comes from the probability of an unlikely main malfunction multiplied by the even less likely probability of a reserve malfunction. This yields an even smaller probability of a double malfunction although the possibility of a main malfunction that cannot be cutaway causing a reserve malfunction is a very real risk.
Parachuting disciplines such as BASE jumping or those that involve equipment such as wing suit flying and sky surfing have a higher risk factor due to the lower mobility of the jumper and the greater risk of entanglement. For this reason these disciplines are generally practiced by experienced jumpers.
Depictions in commercial films — notably Hollywood action movies — usually overstate the dangers of the sport. Often, the characters in such films are shown 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. USPA member drop zones in the US and Canada are required to have an experienced jumper act as a "safety officer" (in Canada DSO – Drop Zone Safety Officer; in the U.S. S&TA – Safety and Training Advisor) who is responsible for dealing with the jumpers who violate rules, regulations, or otherwise act in a fashion deemed unsafe by the appointed individual.
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.
Parachuting and weather
Parachuting in poor weather, especially with thunderstorms, high winds, and dust devils can be a dangerous activity. Reputable drop zones will suspend normal operations during inclement weather.
Canopy Collisions
A collision with another canopy is a statistical hazard, and may be avoided by observing simple principles.
Source: http://en.wikipedia.org/wiki/Parachuting
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