The parachutist's fall from the aircraft causes the static line to become taut, this then pulls the D-Bag out of the container on the jumper's back.
Effectively, the jumper drags the parachute behind him, causing the upward-rushing wind to force open and inflate the canopy.
The aim of static line progression is to train students to maintain the correct, stable body position upon exiting the aircraft, and to teach how to deploy the canopy via the pilot chute mechanism.
As mentioned above the parachutist must adopt and maintain a stable body position throughout deployment to minimize the chances of a parachute malfunction.
This method of parachute deployment is commonly used in several ways: Static line jumping carries risk of injury[3] that, according to one study, doubles when performed in combat.