The last in a series of seven tests on the redesigned space shuttle booster joint came off Sunday without a hitch, despite intentional flaws built into the device, Morton Thiokol Inc. said. Rocky Raab, spokesman for the Chicago-based aerospace company, said the test-firing of the joint at the company's plant 25 miles west of Brigham City, Utah, was "by all indications apparently successful."

The 1 p.m. MDT test was performed at Morton Thiokol's Joint Environment Simulator, which uses three shortened rocket cases, two joints and 385 pounds of propellant to mimic pressures present when a full-scale rocket motor is fired. Sunday's JES test incorporated flaws that exposed parts of the redesigned joint to super-hot gases present during launch, Raab said."It appears no gas leaked outside the joint, in spite of the very severe intentional flaws," he said. "That has really raised our confidence for the (full-scale) test at the end of the month."