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How parachutes are deployed
Pilot chute This small, auxiliary parachute functions to deploy the main or the reserve parachute. These can be springloaded, pull-outs or throw-outs.
Learn how a parachute safely returns a person in free fall to the ground
uring free fall, our bodies accelerate at just under ten metres (33 feet) per second squared until we reach a terminal velocity of about 55 metres (180 feet) per second. Hurtling toward the ground at 200 kilometres (124 miles) per hour would be ill-advised without a parachute strapped to your back. Although Leonardo da Vinci is credited with the first parachute design, found scribbled into the margin of his notebook, Louis-Sébastien Lenormand was the first person to demonstrate the parachute in 1783. Early parachutes were made of silk, but these days they are made of synthetic, lightweight materials such as nylon or Kevlar. Once you’ve jumped clear of the plane, you deploy the parachute by pulling on the ripcord that releases the pilot chute. The pilot chute will quickly open and when the air hits it with enough force the main chute will be pulled from its container. It is vital that the main chute is packed precisely, so that it opens correctly behind you and the suspension lines connecting it to your harness do not become tangled. The main parachute is actually designed to open slowly. If the main chute were to open quickly to its full size, it would reduce your free fall speed very suddenly, jerking your body harshly and potentially damaging the parachute itself. A parachute slows you down by increasing your air resistance. Parachutes decrease your terminal velocity by around 90 per cent, allowing you to land at a safe speed of around five metres (16.4 feet) per second. This should be slow enough for you to land gently on your feet when you reach the ground.
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Parafoil cells This is a typical parafoil parachute. It is split into cells that channel air and allow speed and direction to be controlled easily.
Suspension lines Multiple suspension lines connect the parachute’s canopy to the parachute pack. If the lines are too short the drag may be decreased, meaning the parachute will fall faster.
Slider The slider works to slow down the speed at which the parachute deploys, reducing the risk of damage to the canopy and of the suspension lines becoming entangled.
Body straps These straps attach the parachute securely to the individual and must be tightly fastened to hold the parachute in place.
Steering toggle A parachute is equipped with two steering toggles attached to the break lines at the back of the parachute. By pulling both, you can slow your descent.
The AAD sits snugly at the top of the pack and is easily accessible to the owner.
Automatic activation device
026 | How It Works
activation altitude is reached, the AAD will instantly cause the main chute to be cut away and the reserve chute to be deployed. This is particularly useful in situations where an individual has lost consciousness after beginning their freefall, or become distracted and hasn’t monitored their altitude closely. The latest AADs, such as the Vigil 2+, recalculate an individual’s free fall speed every 0.125 seconds, allowing for variations in normal free fall to be accounted for.
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Many experienced skydivers will tell you that their automatic activation device, or AAD for short, is the most important part of their parachute set up. This self-contained mechanical device attaches to the reserve parachute container, and functions to deploy the reserve parachute in a scenario where an individual is incapable of doing this. AADs constantly monitor a diver’s falling speed and altitude so that they know when to activate. If the diver is still falling at a freefall speed when the
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