Booster Does Well in Sub-Scale Test

BRIGHAM CITY, Utah —  A shuttle booster fired in a sub-scale test appeared to perform perfectly, and a final full-scale prelaunch test has been scheduled for later this month, Morton Thiokol Inc. officials said.

“Everything we looked at in our visual inspection looked very good,” Chuck Speak, director of the aerospace company’s redesigned solid rocket motor development, said of the test Sunday.

Engineers during the next 10 days will take apart the booster to inspect the test rocket in detail and make sure that all joints and seals performed as designed, officials said Monday.

The test, using a 40-foot-long motor about one-third the length of a fully assembled booster, contained multiple flaws built into the seals of field joints. It was the final sub-scale test planned before the launch of Discovery. A final full-scale test will take place later in the month, although a date has not been set.

There were so many intentional defects in the test booster’s seals that “I think if you’d held it up to the light you could have seen through this motor,” Morton Thiokol spokesman Rocky Raab said. “But it held.”

The test utilized 385 pounds of solid propellant, burned in just six-tenths of a second. But pressure was allowed to build inside for two minutes to simulate an actual booster firing. A full-size booster uses 1.1 million pounds of fuel.