Simultaneously , the weight of the payload PL exerts a downward force through the riser RS and tightens the LFB .
As the canopy opens , the reefing line at the skirt expands and exerts an upward force and pull the control line CL upward from the LFB .
, the weight of the payload PL exerts a downward force through the riser RS and tightens the LFB .
As the canopy opens , the reefing line at the skirt expands and exerts an upward force and pull the control line CL upward from the LFB .