1、Lessons Learned Entry: 1225Lesson Info:a71 Lesson Number: 1225a71 Lesson Date: 1999-06-10a71 Submitting Organization: JSCa71 Submitted by: Michael J. Lauer/ Ronald A. MontagueSubject: Planning of the engineering drawing process Description of Driving Event: Part shortages, late engineering changes,
2、and manufacturing difficulties have resulted in a number of minor differences between the structural test article (STA) and the ensuing flight article. Initially, the engineering intent was that the structural subassembly of these two vehicles would be identical from an engineering drawing standpoin
3、t. At the last minute, part shortages required the use of acceptable substitutes for the test article. These last-minute changes carried over to the flight articles, resulting in engineering configuration changes / part number changes for major subassemblies late in the manufacturing cycle, causing
4、delays as the planning/manufacturing paperwork was reworked. Additionally, non-conforming detail parts that are acceptable for the STA only require additional engineering documentation to control their usage to test only if the next assemblies do not account for specific part number differences betw
5、een flight and test. This again has caused delays in getting acceptable hardware installed on schedule.Root cause: Failure to carry part number differences between the flight article and test article early in the design and planning phase.Lesson(s) Learned: Configuration management of drawing change
6、s must consider staging and incorporation of changes into test, qualification, and flight articles in a manner to preclude program, schedule, and budget impactsRecommendation(s): Configure test hardware (carry different part numbers from flight) down to the lowest subassembly level practical early i
7、n the design phase. Inevitably, differences will develop due to unplanned events Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-and since the requirements are different between flight and test, the engineering drawing tree must accommodate these dif
8、ferences else there will be significant schedule impacts downstream. Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): N/AAdditional Key Phrase(s): a71 Administration/Organizationa71 Configuration Managementa71 External Relationsa71 Hardwarea71
9、Policy & Planninga71 Procurement Small Business & Industrial Relationsa71 Research & Developmenta71 Risk Management/Assessmenta71 Safety & Mission Assurancea71 Softwarea71 Test & VerificationAdditional Info: Approval Info: a71 Approval Date: 2002-06-27a71 Approval Name: Ronald A. Montaguea71 Approval Organization: JSCa71 Approval Phone Number: 281-483-8576Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
