Development and Verification of an Aerothermal Thermal Protection System Heat Shield Instrumentation Plug for Flight on Mars Science Laboratory

The National Aeronautics and Space Administration has constructed and over-seen the installation of seven instrumented aerothermal plugs into the Mars Science Laboratory (MSL) heat shield, scheduled for launch in the fall of 2011. Since the MSL heat shield is predicted to experience significant recession from simultaneous turbulent and laminar heating during Mars reentry, development of the aerothermal plugs represents a dramatic commitment in the quantification of flight risk margins resulting from state-of-the-art thermal protection design methodology. The aerothermal plugs were developed and manufactured by NASA Ames Research Center as part of the MSL Entry, Descent, & Landing Instrumentation (MEDLI) project. Each MEDLI Integrated Sensor Plug (MISP) is composed of Phenolic Impregnated Carbon Ablator (PICA), a single isotherm following sensor called the Hollow aErothermal Ablation and Temperature sensor (HEAT), and four thermocouples. This paper will describe the basic design, specifications, and processes used to develop and qualify the plugs for flight to an acceptable level of risk for the flagship mission. Results from random vibration, thermal vacuum, and arc jet testing are also presented.