Parachute Deployment/Flight
When a skydiver wants to deploy their parachute, the most commonly used device used is a manually-operated pilot chute.
The diver will reach back into their rig and grab a handle or small bean bag connected to the pilot chute and throw it away from them.
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(The pilot chute is shown while in the jumper's right hand during deployment)
The small pilot chute is affected by an extra drag force attempting to keep it stationary. When this force and the force of the falling diver create enough tension in the line connected to the pilot chute, the deployment bag containing the main canopy is unstowed.
If the main canopy were to expand to full size immediately, the tensile forces between the diver and the main canopy would most likely kill the diver and/or break the lines. To prevent this, a piece of fabric called a slider sits near the top of the lines, attached to them with metal rings. The main canopy begins to expand, slowed by the slider's movement down the lines toward the diver. Once the canopy is fully extended, the surface area in our drag force equation increases which causes the drag force to increase. Since the force up is now greater than the force down, the acceleration of the skydiver becomes negative and they slow down. In about 10 seconds, the diver will slow from 55 m/s to about 4.5 m/s.
The main canopy works on the same principle as an airplane wing and holds the same teardrop shape. Air moving over the canopy travels faster than air moving under the canopy and the weight of the air pressing down on the canopy is decreased.