杏吧原创

Shuttle crew to test puncture repair kits

Astronauts aboard the shuttle Discovery will be testing five different repair techniques, aimed at preventing a similar disaster to that which befell Columbia

ASTRONAUTS aboard the space shuttle Discovery 鈥 which was being readied for its Wednesday launch as New 杏吧原创 went to press 鈥 will be testing five different 鈥減uncture repair kits鈥 designed to prevent the kind of disaster that befell the crew of the shuttle Columbia in 2003.

Columbia was doomed after a piece of foam fell from its external fuel tank during lift-off, punching a hole in panels on its left wing. This allowed superheated gas to breach the orbiter鈥檚 heat-resistant skin during re-entry, and the shuttle disintegrated in seconds.

鈥淎stronauts will be testing five 鈥榩uncture repair kits鈥 designed to prevent disaster鈥

NASA has since developed experimental methods to repair the heat shield in orbit. For example, a mixture of a pre-ceramic polymer sealant and carbon-silicon carbide powder, known as 鈥渘on-oxide adhesive experimental鈥 (NOAX), can repair cracks up to 10 centimetres long on the reinforced carbon-carbon (RCC) panels that cover the orbiter鈥檚 nose and leading edges of its wings. Astronaut Steve Robinson will test NOAX on deliberately damaged RCC panels during a space walk. Discovery will also carry three test kits to patch up the silica tiles that protect its underbelly.