1、Lessons Learned Entry: 0925Lesson Info:a71 Lesson Number: 0925a71 Lesson Date: 2001-02-20a71 Submitting Organization: ARCa71 Submitted by: Chuck Connors, Sr.Subject: KAO (Kuiper Airborne Observatory) Cavity Wall Deflections Description of Driving Event: During the post modification pressure test, th
2、e fore and aft cavity walls deflected inward until it reached the full pressure (8.0 psi) deflection value at only 2psi. The test was stopped because of the large deflections present at only 2psi. An investigation was performed to determine the cause of the large deflection at 2psi. It was determine
3、d that the contractor had underestimated the cavity wall stiffness by a factor of 4.Lesson(s) Learned: Perform independent validation of analysis for critical structures.Recommendation(s): 1. Use both FEM (Finite Element Modeling) and hand calculations for verification.2. Monitor the relative deflec
4、tions between the Telescope Assembly and the aircraft until the pressure reaches a reasonable level.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
5、): a71 Exploration Systemsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Aircrafta71 Computer-Aided Design/Manufacturing/Engineeringa71 Configuration Managementa71 Cryogenic Systemsa71 Flight Equipmenta71 Ground Equipmenta71 Pressure VesselsAdditional Info: Approval Info: a71 Approval Date: 2001-03-05a71 Approval Name: Eric Raynora71 Approval Organization: QSa71 Approval Phone Number: 202-358-4738Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
