Preliminary inspections of redesigned O-ring joints in both boosters used by the shuttle Discovery show they performed as expected during the first post-Challenger launch, officials said Monday.
"It looks super," said John Thomas, the NASA engineer in charge of the booster redesign project. "We got a look at the left side yesterday and the right side this morning. No gases reached (any O-rings) on any joint. They did their job OK."But Thomas said a complete assessment of the rockets' performance will not be possible until the nozzles of both boosters are removed late Monday or Tuesday for an inspection of a different type O-ring seal called a case-to-nozzle joint.
The 14-story rockets burned about 1.1 million pounds of fuel each during the two minutes they fired Sept. 29 to lift Discovery off the pad.
Despite Discovery's landing Oct. 3 at Edwards Air Force Base, Calif., National Aeronautics and Space Administration managers have been waiting for engineers to disassemble the two boosters before calling the mission a complete success.
Shuttle boosters are made of four fuel segments bolted together at three O-ring "field joints," and it was the rupture of an O-ring field joint that doomed Challenger in January 1986. In the wake of that disaster, the boosters were redesigned.
Instead of two O-rings, Discovery's boosters featured three, along with improved insulation and a metal flange called a "capture feature" to firmly lock joint members together, thus preventing the creation of any deadly leak paths.