yee@ames.arc.nasa.gov (Peter E. Yee) (07/01/88)
Sarah Keegan Headquarters, Washington, D.C. July 1, 1988 (Phone: 202/453-8536) Ed Medal Marshall Space Flight Center, Huntsville, Ala. (Phone: 205/544-0034) RELEASE: 88-86 FINAL SHUTTLE MOTOR JOINT TEST SCHEDULED AT MORTON THIOKOL Morton Thiokol, NASA's prime contractor for the Space Shuttle solid rocket motor, will conduct the seventh Joint Environment Simulator (JES) test Sunday, July 3, 1988, at 3:00 p.m. EDT, at its Space Operations facility in Utah. The test is part of the Space Shuttle solid rocket motor redesign program and is the final such test required prior to resumption of Shuttle flights. JES tests are short-duration, ignition pressure tests using full-scale motor hardware to form two field joints. The tests are used to evaluate the redesigned joints. This test article, designated JES-3C, will be extensively flawed, including a wave-type defect in the J-seal bonded insulation of joint A, plus intentional channel-like defects through the J-seal in both joints. In addition, the capture feature O-ring will be flawed in joint A and both the capture feature and primary O-rings will be flawed in joint B. The defects are intended to ensure hot gas flow reaches the primary O-ring in joint A and the secondary O-ring in joint B. This will allow engineers to verify the performance of the O-ring seals under hot gas conditions. The field joints also have both intentional and natural edge unbonds, some of which have been repaired. The test will allow engineers to evaluate the effect of existing unbonds and also to evaluate the effectiveness of unbond repair procedures. Deliberate flaws also will be introduced in some of the primary seals in the motor igniter. -more- -2- About 385 pounds of live propellant are used in a JES test to provide hot gas to duplicate the ignition pressure buildup of a full-size motor. For this test, hot gas and pressure will be retained inside the test article and not allowed to vent until about 2 minutes after ignition. This simulates full-duration motor conditions. -end- This release and other NASA information is available electronically through DIALCOM, INC. For access to NASA NEWS, through this system, contact the NASA NEWS representative, DIALCOM, INC. at 202/488-0550.