1、Lessons Learned Entry: 0087Lesson Info:a71 Lesson Number: 0087a71 Lesson Date: 1992-06-16a71 Submitting Organization: KSCa71 Submitted by: David PenningtonSubject: Payload Retention Latch Assembly (PRLA) Description of Driving Event: OMRSD S073A.90 thru .230 requires verification of voltages, phasin
2、g, and talkbacks to the orbiter. Present talkback verification method for the payload retention latch assembly (PRLA) involves extensive “hot“ pin jumpering during testing using a 79K07833 breakout box and test leads. Improper jumper procedure by inserting a jumper at an incorrect location could res
3、ult in inadvertent shorts or cross connection of live 120 volt and 28 volt electrical lines. This improper procedure could cause PRLA electrical system damage, orbiter interface damage and/or electrical shock/personnel injury.Lesson(s) Learned: Improper jumper procedures during testing cause shorts
4、or cross connection of live 120 volt and 28 volt electrical lines, damaging orbiter interfaces.Recommendation(s): Design a status tester and jumper verification device to ensure proper jumper connections of the PRLA prior to interfacing with the orbiter.Evidence of Recurrence Control Effectiveness:
5、N/ADocuments Related to Lesson: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N/AMission Directorate(s): a71 Space Operationsa71 Exploration SystemsAdditional Key Phrase(s): a71 Energya71 Flight Equipmenta71 Ground Operationsa71 Hardwarea71 Launch Vehiclea71 PayloadsAdditional Info: Approval Info: a71 Approval Date: 1994-06-02a71 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-,-,-
