Drag Characteristics of a Disk-gap-band Parachute with a Nominal Diameter of 1.65 Meters at Mach Numbers from 2.0 to 3.0Supersonic 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. |
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angles of attack average drag coefficients Ballute base-extension diameter canopy angles canopy inflation canopy motions canopy projected areas CDo,eq changes in geometric Comparison conical base extension conical configuration conical skirt cylindrical base extension cylindrical configuration Dacron deployment and inflation deployment spring plate DIAMETER OF 1.65 diameter of 12.19 disk-gap-band parachute models drag forces drag-coefficient values dynamic pressure equivalent drag coefficients extension g Figure 17 flight tests fluctuations in canopy force measurements forebody frequency gore increase in canopy inflation characteristics initial inflation Langley Research Center large-scale flight results load-cell measurements longer suspension lines Mach number range Mach numbers 2.0 model tests NASA number of 3.0 numbers from 2.0 oscillations oscillatory drag parachute canopy porosity of 12.5 projected-area ratios restraining straps resultant angle sequence photographs Supersonic suspension-line length Tensiometer Load cell tensiometer measurements test Mach number test parachutes trailing distance universal joint variations in canopy X/Dâ‚‚