1、Lessons Learned Entry: 0151Lesson Info:a71 Lesson Number: 0151a71 Lesson Date: 1992-10-08a71 Submitting Organization: KSCa71 Submitted by: David PenningtonSubject: Throat Plug and Purge Adapter Assembly Grounding Description of Driving Event: The throat plug and purge adapter assembly, located in th
2、e reaction control system (RCS) primary thruster, provides the means for sealing the RCS primary engine throat during activation, decontamination, and purging. The assembly consists of a tubular structure terminating in an expandable seal, which is inserted through the nozzle skirt. The plug is hand
3、 operable from the opposite end and expands the seal to a diameter larger than the nozzle throat, providing a positive mechanical interference to preclude blow-out. The plug end gasket is removable to permit inspection for cleanliness or deterioration. The assembly also includes a passage for ductin
4、g purge fluid during deactivating and purging to a toxic vapor disposal system. Improperly grounding or a lack of grounding may cause static electricity build-up and electrical sparks which could act as an ignition source for any flammable vapors present.Lesson(s) Learned: Improper/lack of assembly
5、grounding may cause static electricity build-up and electrical sparks which may ignite any flammable vapors present.Recommendation(s): Update OMIs to provide proper grounding procedure of throat plug and purge adapter assembly, as well as positive grounding verification.Evidence of Recurrence Contro
6、l Effectiveness: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N/ADocuments Related to Lesson: N/AMission Directorate(s): N/AAdditional Key Phrase(s): a71 Energya71 Flight Equipmenta71 Ground Equipmenta71 HardwareAdditional 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-,-,-
