Deployment and performance characteristics of 1.5-meter supersonic attached inflatable decelerators

Attached-inflatable-decelerator (AID) canopies fabricated from lightweight Nomex cloth and tapes were deployed in a supersonic stream from the base of a 140 deg conical aeroshell. Characteristics of the deceleration system were obtained over a wide range of Mach number, dynamic pressure, and pitch angle. All models deployed rapidly by ram air and experienced only mild deployment shock loads. Steady-state drag coefficients as high as 1.3 were obtained in the supersonic stream and were relatively insensitive to Mach number, dynamic pressure, and pitch angle. All models were free of fluttering motion. Results also showed that the AID is aerodynamically more efficient without a burble fence in a supersonic stream. Though measured meridian-tape loads were higher than those predicted by theory, the ram-air deployment rates and steady-state drag coefficients were in good agreement with theory. These results indicate that the AID is a stable, efficient decelerator in a supersonic stream and its performance is readily predictable.