Researchers in the US have developed a heat-shield material to protect reusable autonomous spacecraft returning from orbit, writes Nick Flaherty.

The thermal protection system (TPS) is based on silicon carbide. Developed at the Oak Ridge National Laboratory and Sierra Space, the TPS is composed of a tile face made from advanced materials and an insulative tile backing, which, when installed on a space vehicle, will be able to withstand multiple launches and the high temperatures of atmospheric re-entries over short periods of time.

The high temperature and corrosion stability properties of silicon carbide are merged with the

high-strength, high-temperature consistency of carbon fibre. The two materials are combined into a low-density, low-profile, composite thermal barrier that is critical for providing insulative protection and stable flight dynamics. This will help maintain the aerodynamic surface over multiple flights by resisting changes to size and shape.

“Keeping a consistent outer mould line is important for reusability,” said ORNL principal investigator Greg Larsen, referring to the need for a smooth exterior surface. “It keeps the aerodynamics the same to allow the vehicle to fly as designed.

“The key to achieving a flight cadence driven by fast landing-to-launch turnaround times is reusability of the TPS. The materials we are exploring will push the boundaries of reusability that translate directly to commercial viability for space access providers.”

ORNL and Sierra Space have completed the first material-development phase of the project, and they have jointly applied to patent it. The second phase will focus on developing a manufacturing process for the insulative tile backing.

Sierra Space plans to use the TPS on the DC-100 Dream Chaser, a winged commercial spaceplane, designed to carry crew and cargo into low-Earth orbit.