1、Lessons Learned Entry: 0163Lesson Info:a71 Lesson Number: 0163a71 Lesson Date: 1992-10-15a71 Submitting Organization: KSCa71 Submitted by: David PenningtonSubject: 750 psig GN2 Supply Description of Driving Event: The supply system for the 750 psig GN2 is designed such that pressure may not be remov
2、ed from flodyne valves for removal/replacement, a SCAPE operation, without removing pressure which actuates other relevant components. Inadequate isolation capability of actuation pressure could result in loss of valve control, allowing valve to open when it should be closed. This could allow trappe
3、d residuals in the cross country line to drain back to the storage area, possibly resulting in a hypergol spill or fire.Lesson(s) Learned: Failure of the system to provide the ability to isolate and vent 750 PSIG GN2 actuation pressure to individual flodyne valves.Recommendation(s): Install isolatio
4、n and vent valves to permit depressurizing individual flodyne valves in pneumatic panels for maintenance.Evidence of Recurrence Control Effectiveness: N/AProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Documents Related to Lesson: N/AMission Director
5、ate(s): N/AAdditional Key Phrase(s): a71 Hardwarea71 LogisticsAdditional 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-,-,-