Jerry Berg Marshall Space Flight Center, Huntsville, Ala. RELEASE: 89-2 SPACE SHUTTLE SOLID ROCKET MOTOR SLATED FOR FINAL TEST FIRING A full-scale static test firing of NASA's redesigned Space Shuttle solid rocket motor is scheduled for January 17. The test will be the sixth and final such firing required to qualify the major design features of the redesigned solid rocket motor. The 126-foot-long, 1.2-million-pound Qualification Motor-8 (QM-8) will undergo a full-duration horizontal test firing of 2 minutes. The 1 p.m. MST firing will take place in test bay T-97 about 25 miles west of Brigham City. Prior to the firing, the QM-8 motor will be cooled down to 40 degrees F. during a period of 30 days prior to the firing. That is its lowest specified operating temperature and is lower than any expected motor temperature at launch. The test is part of the Shuttle motor redesign program. The verification and qualification test program to certify the motor redesign consists of five full-duration tests, conducted prior to resumption of Shuttle flights last Sept. 29, and the upcoming test under cold-weather conditions. Morton Thiokol is NASA's prime contractor for the solid rocket motor, and the Marshall Space Flight Center in Huntsville, Ala., manages the motor program for NASA. QUALIFICATION MOTOR FACT SHEET Qualification motor (QM-8) is a full-size Space Shuttle solid rocket motor, approximately 126 feet in length and 12 feet in diameter. The motor weighs 1.2 million pounds including 1.1 million pounds of propellant. The QM-8 motor will be conditioned to a mean or average bulk propellant temperature of 40 degrees F. This is several degrees cooler than any expected motor temperature at launch and will demonstrate margins of safety. The T-97 test bay, in which the firing will take place, can provide chilled air as low as 20 degrees F. to cool the motor's large mass of propellant to a 40- degree average. The three field joints which connect the motor segments are of the flight configuration, capture feature tang-and-clevis design with three Viton (TM) O-rings and an adhesively bonded, J- shaped deflection relief slot at each field joint which reduces stresses and also increases the sealing action of the bonded surfaces under motor pressure. Joint heaters, mounted around the motor case at each field joint location, are thermostatically controlled to maintain joint temperatures at a minimum of 75 degrees F. In addition, the igniter joint will have heaters to maintain a minimum of 66 degrees F. and the aft skirt will be conditioned with heated air to assure a minimum case-to-nozzle joint temperature of 75 degrees F. These temperatures are the same as for a launch. The motor case-to-nozzle joint on QM-8 also is of the flight configuration, incorporating 100 radial bolts, adhesively bonded insulation surfaces, a shaped relief slot and an added Viton "wiper" O-ring designed to keep the adhesive on the insulation surfaces during assembly. None of the joints in the QM-8 motor contain intentional manufacturing or assembly defects. The QM-8 motor is equipped with a flight design external tank attachment ring. Three hydraulically actuated struts, which simulate the motor's connection to an external tank, are attached to the ring. During the motor firing, a programmed series of dynamic loads will be applied through the external tank attach struts to simulate ignition, liftoff and flight loads. Response of the QM-8 motor to those loads will be monitored by special instrumentation. The QM-8 motor is fitted with more than 600 instruments to measure acceleration, pressure, deflection, thrust, strain, temperature, electrical properties and other conditions.