NASA successfully tests hypersonic inflatable heat shield
24 July 2012
A large inflatable heat shield developed by NASA's Space Technology Programme has successfully survived a trip through Earth's atmosphere while travelling at hypersonic speeds up to 3.4km/s.
The Inflatable Re-entry Vehicle Experiment (IRVE-3) was launched by sounding rocket yesterday (July 23) from NASA's Wallops Flight Facility. The purpose of the IRVE-3 test was to show that a space capsule can use an inflatable outer shell to slow and protect itself as it enters an atmosphere at hypersonic speed during planetary entry and descent, or as it returns to Earth with cargo from the International Space Station.
IRVE-3, a cone of uninflated high-tech rings covered by a thermal blanket of layers of heat resistant materials, launched from a three-stage Black Brant rocket for its sub-orbital flight. About 6 minutes into the flight, as planned, the 300kg inflatable aeroshell, or heat shield, and its payload separated from the launch vehicle's 560mm diameter nose cone about 280 miles over the Atlantic Ocean.
An inflation system pumped nitrogen into the IRVE-3 aeroshell until it expanded to a mushroom shape almost 3,000mm in diameter. Then the aeroshell plummeted at hypersonic speeds through Earth's atmosphere. Engineers in the Wallops control room watched as four onboard cameras confirmed the inflatable shield held its shape despite the force and high heat of reentry. Onboard instruments provided temperature and pressure data. Researchers will study that information to help develop future inflatable heat shield designs.
After its flight, IRVE-3 fell into the Atlantic Ocean off the coast of North Carolina. From launch to splashdown, the flight lasted about 20 minutes. A high-speed U.S. Navy Stiletto boat is in the area with a crew that will attempt to retrieve IRVE-3.
This test was a follow-on to the successful IRVE-2, which showed an inflatable heat shield could survive intact after coming through Earth's atmosphere. IRVE-3 was the same size as IRVE-2, but had a heavier payload and was subjected to a much higher re-entry heat, more like what a heat shield might encounter in space.