Critical characterization of low porosity ripstop parachute canopies using smallscale impact and quasi-static loading principle

Abstract

Three levels of maximum sustainable tensile impact load (400, 450 and 500 N) of a small rectangular ripstop parachute canopy specimen stitched at a 45° seam angle have been studied manually. Using the scale-up approach, the proportionate peak sustainable opening shock force for T10, C9, and G11 low porosity canopies have been computed subsequently. This study also characterizes the small rectangular unseamed and seamed specimens at 0° and 45° seam angles under three levels of a maximum sustainable range of tensile impact and quasi-static loads. The ANOVA analysis shows that the fabric seam joining has a greater effect on the specimen’s performance than the seam angle and applied load. It is also observed that the specimen degrades significantly more under impact load than the corresponding quasi-static load. Under quasi-static and impact loads, the seamed specimen exhibits more strength and elongation loss than the unseamed specimen. Further, the strength loss for the 0° seam angle is more than the 45° seam angle. The specimen with 45° seam angle exhibits better performance under impact and quasi-static load comparably and exhibits higher loss in elongation but still has higher breaking elongation than the specimen stitched with 0° seam angle at the same load level.