Mars Science Laboratory Parachute Development Test Program

Abstract

The design development and structural qualification of the Mars Science Laboratory (MSL) parachute decelerator system (PDS) took place at NASA Ames in the 80 x 120 foot wind tunnel of the National Full-Scale Aerodynamics Complex (NFAC). This facility provided the MSL program with the ability to systematically perform full-scale infinite mass inflations, which were critical to simulating the parachute loads expected during Mars atmospheric descent. The enormous size of the 21.5m to 23m Disk Gap Band (DGB) test articles created a wide range of daunting issues, which the test program had to overcome before the MSL parachute could be qualified. These problems ranged from band leading edge inversion failures during mortar deployments to excessive damage incurred by the parachute during reefed deployments. Through the extensive use of still, high definition, and high speed photography, these issues were analyzed and innovative solutions were implemented. These solutions ranged from adding anti-inversion netting to the leading edge of the parachute to developing the revolutionary sleeve deployment technique. The outcome of this work was a highly successful qualification test program, which structurally qualified the 21.5m MSL DGB parachute through a mortar deployment and nine area oscillations using the sleeve deployment methodology. Without the NFAC wind tunnel facility, the unparalleled quantity and quality of information produced, and the innovative implementation of mortar and sleeve deployments, this test program would have never satisfied the MSL parachute strength qualification requirements. Furthermore, the unmatched amount of data produced on the inflation dynamics of the DGB parachutes and the development of new deployment techniques will leave a legacy for future parachute programs to leverage upon. Nomenclature