temperatures on the airframe were expected to be 980 °c (1800 °f) over a large part of the surface, with maxima of more than 1650 °c (3000 °f) on the leading edges and portions of the engine. this required the development of high temperature lightweight materials, including alloys of titanium and aluminum known as gamma and alpha titanium aluminide, advanced carbon/carbon composites, and titanium metal matrix composite (tmc) with silicon carbide fibers. titanium matrix composites were used by mcdonnell douglas to create a representative fuselage section called "task d". the task d test article was four feet high by eight feet wide by eight feet long. a carbon/epoxy cryogenic hydrogen tank was integrated with the fuselage section and the whole assembly, including volatile and combustible hydrogen, was successfully tested with mechanical loads and a temperature of 820 °c (1500 °f) in 1992, just before program cancellation.