Inflatable spacecraft shield a success

NASA launched an inflatable spacecraft heat shield on Monday to test the technology for use on future space missions.

The test flight lofted a vacuum-packed shroud atop a small sounding rocket from NASA's Wallops Flight Facility on Wallops Island, Va. Several minutes after liftoff, the shield inflated to a 10-foot-diameter mushroom shape, and fell back to Earth.

The experiment showed that such a device could be used to slow and protect a space capsule as it enters the atmosphere at hypersonic speeds. The material - several layers of silicone-coated Kevlar - could be used to insulate a crew and cargo from the searing temperatures of re-entry.

"This was a huge success," said Mary Beth Wusk, project manager for the Inflatable Re-entry Vehicle Experiment (IRVE), based at Langley. "IRVE was a small-scale demonstrator. Now that we've proven the concept, we'd like to build more advanced aeroshells capable of handling higher heat rates."

Today's test flight was the first time anyone has successfully flown an inflatable re-entry capsule, according to engineers at NASA's Langley Research Center.

The experimental shield was flown to an altitude of 131 miles atop a Black Brant 9 rocket. After a four-minute climb, it was released from its cover and pumped full of nitrogen in less than 90 seconds.

"Everything performed well, even into the subsonic range, where we weren't sure what to expect," said Neil Cheatwood, IRVE principal investigator and chief scientist for the Hypersonics Project of NASA's Aeronautics Research Mission Directorate's Fundamental Aeronautics Program. "The telemetry looks good. The inflatable bladder held up well."

Scientists are interested in using similar shields to help land large objects on Mars.

"We'd like to be able to land more mass on Mars," Cheatwood said. "To land more mass you have to have more drag. We need to maximize the drag area of the entry system. We want to make it as big as we can, but the limitation has been the launch vehicle diameter."

The idea of inflatable decelerators has been around for 40 years, Cheatwood said, but until now did not seem practical because of concerns over whether materials could withstand the heat of re-entry. Over time materials have advanced enough to make the concept plausible. In addition, a greater understanding of the Martian atmosphere gleaned from Mars rovers, landers and orbiters indicates that the plan has potential