<P> RCC was a laminated composite material made from carbon fibres impregnated with a phenolic resin . After curing at high temperature in an autoclave, the laminate was pyrolized to convert the resin to pure carbon . This was then impregnated with furfural alcohol in a vacuum chamber, then cured and pyrolized again to convert the furfural alcohol to carbon . This process was repeated three times until the desired carbon - carbon properties were achieved . </P> <P> To provide oxidation resistance for reuse capability, the outer layers of the RCC were coated with silicon carbide . The silicon - carbide coating protected the carbon - carbon from oxidation . The RCC was highly resistant to fatigue loading that was experienced during ascent and entry . It was stronger than the tiles and was also used around the socket of the forward attach point of the orbiter to the External Tank to accommodate the shock loads of the explosive bolt detonation . RCC was the only TPS material that also served as structural support for part of the orbiter's aerodynamic shape: the wing leading edges and the nose cap . All other TPS components (tiles and blankets) were mounted onto structural materials that supported them, mainly the aluminum frame and skin of the orbiter . </P> <P> This white, flexible fabric offered protection at up to 371 ° C (700 ° F). FRSI covered the orbiter's upper wing surfaces, upper payload bay doors, portions of the OMS / RCS pods, and aft fuselage . </P> <P> Gap fillers were placed at doors and moving surfaces to minimize heating by preventing the formation of vortices . Doors and moving surfaces created open gaps in the heat protection system that had to be protected from heat . Some of these gaps were safe, but there were some areas on the heat shield where surface pressure gradients caused a crossflow of boundary layer air in those gaps . </P>

Who invented the tiles on the space shuttle