Thermal Protection System for the Space Shuttle External Tank: Applications of Instrumental Methods of Analysis

Abstract

External Tanks (ET's) for Space Shuttle missions are coated with isocyanurate foams. These materials must perform as an insulator for cryogenic propellants and as an ablator during ascent conditions. Because of the limited high- temperature stability of conventional urethane foams, qualification of Spray-On Foam Insulation (SOFI) systems was undertaken early in the Shuttle program. The criteria used to chemically evaluate the individual components of the in sulation and the flame retardancy tests correlating composition, radiant reces sion rate and bond tension of the finished product are described in this paper. Laboratory methods to measure and control predefined component ratios for production units are also discussed.

Keywords

Isocyanurate foam insulation Space Shuttle External Tank HPLC TG dTG flame retardants.

Get full access to this article

View all access options for this article.

References

Ronquillo, L. and Williams, C. , J Therm. Insul, 7, 228 (1984).

Reymore, H.E. , Jr., Carleton, P.S. , Kolakowski , R.A. , and Sayigh, A.A.R. , J Cell Plast , 11, 328 (1975).

Ashida, K. and Frisch, K.C. , J Cell Plast , 8, 160 (1972).

Grieve, R.L. , Belgian Patent 745,003 (January 27, 1969).

Matienzo, L.J. , Shah, T.K. , and Gibbs, A.J. , to be published.

Matienzo, L.J. , Shah, T.K. , and Venables, J.D. , 13th Annual Conference of the North American Thermal Analysis Society, Philadelphia, PA (September 23-26, 1984).