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The Surface Protected Ablator (SPA) is a lightweight and cost effective thermal protection for single use reentry capsules. It is characterised by a combination of load carrying structure, ablator and abrasion protection system. A simulation software has been developed to predict the thermal behaviour of the SPA during plasma wind tunnel tests and under atmospheric reentry conditions. Test samples have been exposed to different aerothermal heat fluxes. Test results have been used to calibrate the numerical model and to determine unknown properties of the ablative material. The calibrated model was applied for accurate flight predictions of the MIRKA reentry.

Thermal design features of the ESA European Polar Platform are described. Due to the low conductivity of the CFRP/aluminium honeycomb sandwich panels of the Payload Equipment Bay, carbon/carbon thermal doublers are used as heat spreaders for high dissipating units. The main challenge for the thermal design of the Data Relay Satellite Terminal Outboard Assembly are the motor gears and the rotary joints. High RF dissipation combined with low thermal capacitances result in extreme orbital temperature variations. The temperature limits are met by a proper selection of thermooptical properties and thermostatically controlled heaters.

Actively cooled and re-radiative leading edges were investigated as typical thermal protection elements for thermally high loaded areas of advanced launchers. A performance trade-off led to the selection of a C/SiC thermostructural concept. Mechanical and thermal analyses demonstrated the adequacy of the selected design. Manufacturing leading edge demonstrators with a small nose radius, different thicknesses of the outer skin and the integration of stringers was realised with good surface smoothness and contour accuracy. Thermal cycle tests with temperatures up to 1000°C in an oxidising environment were performed without any visible damage.

Spacecraft which are designed for Mars exploration are exposed to different severe thermal environments. The Thermal Control Design for small Mars landers which are being developed for the MARSNET mission is described. During transfer from Earth to Mars they experience large variations of the incident solar radiation, caused by solar aspect angle variations and the decreasing solar radiation intensity. The entry phase into the Martian atmosphere is characterized by a short aerothermodynamic heating, requiring a dedicated Thermal Protection System. Arrived on the Mars surface, the landers are exposed to an extreme thermal environment with large diurnal and seasonal variations of the atmospheric temperature and the incident solar radiation. The main emphasis is put on the description of the Martian thermal environment and the Thermal Control design for the Mars operation phase.

Thermal protection systems (TPS) for hypersonic transport vehicles are described and evaluated. During the flight through the atmosphere moderate to high aerodynamic heating rates with corresponding high surface temperatures are generated. Therefore, a reliable light- weight but effective TPS is required, that limits the heat transfer into the central fuselage with the liquid hydrogen tank and that prevents the penetration of the temperature peak during stage separation to the load carrying structure. The heat transfer modes in the insulation are solid conduction, gas conduction, gas convection and radiation. Thermal protection systems based on different phenomena to reduce the heat transfer, like vacuum shingles, inert gas filled shingles, microporous insulations and multiwall structures, are described. It is demonstrated that microporous and multiwall insulations are efficient, light weight and reliable TPSs for future hypersonic transportation systems.