1、Lessons Learned Entry: 0185Lesson Info:a71 Lesson Number: 0185a71 Lesson Date: 1992-10-29a71 Submitting Organization: KSCa71 Submitted by: Lisa L. MusgraveSubject: Space Shuttle Main Engine (SSME) Testing Description of Driving Event: The SSME design verification specifications are evaluated by anal
2、ysis, laboratory testing, subsystem testing, and/or engine hot fire testing. Tests are planned to expose problems early and consist of over-stress tests, off limits tests, and malfunction tests. The ground test program prior to the STS 51-L accident was questionable. The number of tests per month ha
3、d decreased during a two year period prior to the accident. The SSME development program specifies a ground hot fire test program that includes multiple engines of the flight configuration, with maintenance and inspections, that demonstrates hot fire operational time far in excess of the orbiter fle
4、et leader engine. It also pursues engine hot fire tests that demonstrate the limits of the engine operational parameters and margins or over-stress tests to verify the full engine capability. Further, margin tests should be conducted to the extent that they reasonably represent potential engine oper
5、ation in a degraded state.Lesson(s) Learned: Demonstration of the full margin extent of critical engine components, subsystems, and systems were omitted during testing.Recommendation(s): Continue SSME over-stress, limit, and malfunction testing to demonstrate the full engine capabilities.Evidence of
6、 Recurrence Control Effectiveness: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N/ADocuments Related to Lesson: N/AMission Directorate(s): a71 Space Operationsa71 Exploration SystemsAdditional Key Phrase(s): a71 Ground OperationsAdditional 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-,-,-