REG NASA-LLIS-0175-1992 Lessons Learned - Solid Rocket Motor (SRM) Field Joints.pdf

1、Lessons Learned Entry: 0175Lesson Info:a71 Lesson Number: 0175a71 Lesson Date: 1992-10-23a71 Submitting Organization: KSCa71 Submitted by: Lisa L. MusgraveSubject: Solid Rocket Motor (SRM) Field Joints Description of Driving Event: The SRM Is the primary propulsive element for the space shuttle. The

2、 SRM consists of: an insulated and lined segmented rocket motor case loaded with solid propellant; an ignition system complete with electromechanical safe and arm device, initiator, and load ignitor; a movable nozzle; raceway bracketry; instrumentation; and the necessary integration hardware. Struct

3、urally, a SRM is configured with a forward rocket motor segment, two center rocket motor segments, and one aft rocket motor segment. A field joint is that portion of the SRM segment that is assembled/stacked at KSC to create the finished SRM. These field joints are susceptible to environmental condi

4、tions and were not qualification tested to the full range of environments. This led to a lack of complete understanding of the joint design limits.Lesson(s) Learned: All environmental specifications imposed by NASA for the SRM were inadequately verified by test, analysis, and similarity.Recommendati

5、on(s): Prior to each launch, conduct qualification testing of the SRM over the full range of possible environments.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N/AMissio

6、n Directorate(s): a71 Space Operationsa71 Exploration SystemsAdditional Key Phrase(s): a71 Environmenta71 Flight Equipmenta71 Test & VerificationAdditional Info: Approval Info: a71 Approval Date: 1994-06-06a71 Approval Name: James G. Klinea71 Approval Organization: KSC/HEIa71 Approval Phone Number: 407-867-7614Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-