1、Lessons Learned Entry: 0124Lesson Info:a71 Lesson Number: 0124a71 Lesson Date: 1992-08-20a71 Submitting Organization: KSCa71 Submitted by: Lisa L. MusgraveSubject: Payload Bay Duct Heater Overtemp Description of Driving Event: The payload bay duct heater adds measured quantities of heat independentl
2、y to each duct system. This raises the temperature of the process air from the cooling coils to the desired interface temperature leaving the portable purge unit and engine control system room. With no overtemp switches installed, excessive heat from the payload bay duct heaters burned through the d
3、uct insulation, causing severe damage with a potential for orbiter damage.Lesson(s) Learned: Excessive heat from payload bay duct heaters may cause severe damage to ducting, insulation, and orbiter payload bay.Recommendation(s): Design and install high temperature cutoff switches in payload bay duct
4、 heaters for overtemp emergency shutdown.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Mission Directorate(s): N/AAdditional Key Phrase(s): a71 Hardwarea71 Launch VehicleAdditional 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-,-,-
