1、Lessons Learned Entry: 0078Lesson Info:a71 Lesson Number: 0078a71 Lesson Date: 1992-05-20a71 Submitting Organization: KSCa71 Submitted by: David PenningtonSubject: Insulation Baking Process for RCS Thrusters Description of Driving Event: Three RCS primary thruster injector/chamber assemblies were da
2、maged when the oven temperature control system malfunctioned and permitted the temperature to reach an estimated 1400 deg F during a cerachrome insulation baking process that should have been limited to 625 deg F. These units should have been rejected at this point, but quality assurance was not not
3、ified. As a result, the full extent of damage was not determined until the severe discoloration of titanium alloy and columbium parts was noted during the post-baking weighing process, about three weeks later.Lesson(s) Learned: Lack of redundant high temperature cut-off switches allowed 3 RCS thrust
4、ers to be over heated during insulation baking process.Recommendation(s): Install redundant separate high temperature cut-offs on the oven power supply with appropriate alarm systems.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AProvided by IHSNot for ResaleNo repr
5、oduction or networking permitted without license from IHS-,-,-Mission Directorate(s): N/AAdditional Key Phrase(s): a71 Ground Operationsa71 Ground Equipmenta71 HardwareAdditional Info: Approval Info: a71 Approval Date: 1994-06-15a71 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-,-,-
