Study on glide performance of ram air parachute

To learn the glide performance of ram air parachute,the maximum lift-drag ratio was derived theoretically by regarding whole system as a longitudinal 3-DOF static model. Glide ratios of parafoil with different canopy rigging angles were calculated and the best rigging angle was also solved. Increasing maximum lift coefficient and decreasing zero-lift drag are two methods of promoting glide ratio. Larger airfoil camber results in better glide ratio,because it increases maximum lift coefficient. The side effect of large airfoil camber is sensitivity of canopy rigging angle. In other words,small error of rigging angle could lead to huge departure from design point. Decreasing payload drag or zero-lift drag can both improve glide performance,and the latter is more effective.