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The Mars Science Laboratory (MSL) Entry Descent and Landing Instrumentation (MEDLI) suite on MSL entry vehicle heatshield has successfully returned pressure, temperature, and thermal protection system (TPS) ablation data acquired during entry. This paper provides an initial assessment of MEDLI thermal instrumentation data that is comprised of in-depth temperatures in the TPS made of Phenolic-Impregnated Carbon Ablator (PICA). Temperatures are measured in-depth at seven different locations on the surface. The thermal sensor plugs are also characterized in arc jet facilities to quantify measurement uncertainties and biases. The assessment of flight data provides key insights into boundary layer transition to turbulence, surface recession, turbulent heating augmentation, stagnation point and apex laminar heating, and in-depth thermal response. A preliminary comparison with model results highlights inadequacies in our predictive capability. The peak temperature measured by near surface thermocouples was found to be 1049 C in the vicinity of apex region. Initial estimate of peak surface temperature with nominal model settings is about 1575 C. The peak heat flux was found to be on the leeside of the vehicle as predicted, but its value is sensitive to the recession model.

The Mars Science Laboratory (MSL) entry vehicle successfully landed on the Martian surface on August 5, 2012. A phenolic impregnated carbon ablator heatshield was used to protect the spacecraft against the severe aeroheating environments of atmospheric entry. This heatshield was instrumented with a comprehensive set of pressure and temperature sensors. The objective of this paper is to present the thermal flight data returned and provide a preliminary post-flight analysis of MSL's aerothermal environment and heatshield thermal response. The flight temperature data are compared with the thermal response predictions by the same analytical models used in heatshield design. In addition to this direct comparison, a preliminary inverse analysis is performed where the time-dependent surface heating is estimated from flight-measured subsurface temperature data.

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The Mars Science Laboratory entry vehicle successfully landed the Curiosity rover on the Martian surface on 5 August 2012. A phenolic impregnated carbon ablator heatshield was used to protect the spacecraft against the severe aeroheating environments of atmospheric entry. This heatshield was instrumented with a comprehensive set of pressure and temperature sensors. The objective of this paper is to perform an inverse estimation of the entry vehicle's surface heating and heatshield material properties. The surface heating is estimated using the flight temperature data from the shallowest thermocouple. The sensitivity of the estimated surface heating profile to estimation tuning parameters, measurement errors, recession uncertainty, and material property uncertainty is investigated. A Monte Carlo analysis is conducted to quantify the uncertainty bounds associated with the nominal estimated surface heating. Additionally, a thermocouple driver approach is employed to estimate heatshield material properties using the flight data from the deeper thermocouples while applying the shallowest thermocouple temperature as the surface boundary condition.