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Ten flight tests of modified-ringsail, disk-gap-band, and cross parachute configurations with deployment at Mach numbers and dynamic pressures corresponding to conditions expected during entry into a Martian atmosphere have been completed. Comparison of flight results indicates that theoretical snatch force values were never exceeded when the deployment techniques of these tests were used. Opening loads showed no definite trend with Mach number. Values for filling times compared favorably with generally accepted empirical curves based on 15-percent geometric porosity. Canopy stability was good when Mach numbers were below 1.4 for the modified-ringsail and disk-gap-band configurations.
Exploratory wind-tunnel tests of the disk-gap-band and modified ringsail parachute configurations have been conducted at dynamic pressures between 0.24 and 7.07 lb/ft2 (11 and 339 N/m2). Both parachutes exhibited positive inflation characteristics over the range of the tests within technique limitations. The disk-gap-band configuration required less time and distance to inflate than the modified ringsail configuration did.
Supersonic wind-tunnel tests were conducted with disk-gap-band parachute models having a nominal diameter of 1.65 meters and geometric porosities of 10.0, 12.5, and 15.0 percent. Canopy inflation characteristics, angles of attack, and drag performance are presented for deployment behind forebody base extensions which were free to oscillate in pitch and yaw. The effect of increasing suspension-line length on canopy motions and drag performance is included, and the drag performance of a model with 12.5 percent geometric porosity is compared with results from flight tests of a parachute with a nominal diameter of 12.19 meters.