High-temperature ceramics takes flight

A recent NASA flight test ending at the Kwajalein missile range in the Pacific might lead to a new aerospace design that would make the space shuttle look downright old-fashioned.

At the end of September, NASA sent four 5-inch, triangular forms made of so-called ultrahigh-temperature ceramics into space for a 23-minute flight. Scientists have proposed that such materials could help improve a spacecraft’s leading edges, where heat and other degradative processes are most pronounced. During the NASA flight, the vehicle retracted two of the forms, or strakes, from their exterior position just before they were expected to start burning up, and the other two were retracted a bit later. Meanwhile, sensors recorded the temperature in the strakes and transmitted the data to Earth.

NASA’s recent trial hit a snag when a parachute malfunctioned and the return vehicle hit the water at least three times as fast as intended. Jeff Bull of NASA’s Ames Research Center in Mountain View, Calif., notes, however, that even if the strakes shattered inside the vehicle, he and his colleagues still will be able to conduct their planned microscopic analyses of temperature effects on the ceramics.

Researchers hope that what they learn about the materials will enable designers to sharpen a spacecraft’s leading edges, which could result in improved vehicle maneuverability. The shuttle’s cumbersome, blunt body reflects a design strategy to counter the high heat that it encounters on reentering Earth’s atmosphere.

Sharp edges, such as those found on supersonic jet wings, might offer a manned spacecraft enough flexibility to land at any airport around the globe, Bull told Science News from Kwajalein. Aerodynamic shapes also would enable spacecraft to carry more mass and possibly reduce mission costs. Moreover, they could reduce or eliminate the communication blackout created when the space shuttle’s body creates a thick shock wave of ionized gases on reentry.