🚀 go-pugleaf

In sci.space.shuttle, BrianT@cup.portal.com (Brian Stuart Thorn) writes:
>     The shuttle uses many different types of thermal insulation. There
>     are tiles and thermal blankets, and there are varieties of each.
>     The black tiles are rated for the highest temperatures and are used
>     where the shuttle gets the greatest heating (the underside, the nose,
>     and the leading edge of the tail). White tiles are next, with the
>     second-highest rated protection, and are used on the forward fuselage,
>     the aft area, and the tail. The lowest temperatures on the shuttle
>     are experienced on the upper surfaces, i.e., the tops of the wings
>     and the tops of the payload bay doors...
>     
>     That's a simple, but not complete or 100% accurate description. The
>     Shuttle also uses a grey thermal insulation on the wing leading
>     edges, but I'm not sure which category they belong to.

  The grey insulation is a composite material called RCC (reinforced
carbon-carbon).  It is used only on the nose of the orbiter, and the leading
edges of the wings - the two places where the orbiter gets hottest during
descent. RCC can withstand much higher temperatures than the black tiles can.

  The principal drawback of RCC is the price - I heard once that, to replace a
half-meter strip on one of the orbiter's wings cost somewhere around $6 million
bucks...

Ty Willis
Stephen F. Austin State University
a_willisgt@ccsvax.sfasu.edu