1、Lessons Learned Entry: 0610Lesson Info:a71 Lesson Number: 0610a71 Lesson Date: 1999-02-03a71 Submitting Organization: GSFCa71 Submitted by: Charles Powers/Elizabeth SmithSubject: Long-Term Life Testing of Spacecraft Components Description of Driving Event: Since 1980, the Materials Engineering Branc
2、h has been involved in operational life testing of spacecraft components. These include encoder lamps and light emitting diodes, calibration lamps, signal amplifiers and support bearings for scanning mechanisms. Many of these life tests were initiated to demonstrate that life sensitive components wo
3、uld meet mission lifetime requirements. Several of the life tests were also used to determine the cause of in-flight failures of components. Besides demonstrating that a component would meet mission lifetime requirements, these life tests also determined useful lifetime and long-term behavior of com
4、ponents. In some cases, the behavior of a component at the beginning of life was used to develop screening techniques to select longer lived parts.Reference(s): /1009454main1_0610.pdf by Chuck Powers, 10/21/98 (PDF File)Lesson(s) Learned: 1. Accelerated life testing can lead to incorrect lifetime pr
5、edictions if the failure modes are not understood.2. Instrumentation and high data rates during a life test can provide an understanding of component behavior and can lead to effective screening techniques.Recommendation(s): 1. Use accelerated life testing cautiously because failure modes can change
6、 between accelerated and operating conditions. If accelerated life testing is your only choice, make sure you understand the failure mechanisms of your component.2. Thoroughly characterize your components prior to life testing. You can conduct a meaningful Provided by IHSNot for ResaleNo reproductio
7、n or networking permitted without license from IHS-,-,-life test with a small quantity of well characterized parts.3. Instrument as much as you can during a life test and use automation for monitoring a life test. Also, take lots of data during the life test.4. Perform a thorough post life test anal
8、ysis of your components.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): N/AAdditional Key Phrase(s): a71 Research & Developmenta71 Test & VerificationAdditional Info: Approval Info: a71 Approval Date: 1999-03-02a71 Approval Name: Ellen L. Herringa71 Approval Organization: 300a71 Approval Phone Number: 301-286-7393Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
