1、Lessons Learned Entry: 0546Lesson Info:a71 Lesson Number: 0546a71 Lesson Date: 1996-04-01a71 Submitting Organization: LARCa71 Submitted by: Ruth M. AmundsenSubject: Venting Design for Small Pressure Changes Description of Driving Event: The MIDAS experiment was designed for one atmosphere pressure,
2、and thus venting was not seen as a requirement and was not designed in. However, the specified minimum and maximum pressures on Shuttle and Mir would have produced a potential maximum pressure difference of 4 psi in the worst case. Venting was back-designed into the system after the fact, when this
3、was determined.Lesson(s) Learned: Even if pressure changes will be extremely small, have vent holes designed in everything by CDR.Recommendation(s): It is easier to design venting into the system in the first place than answer questions about what the maximum pressure change might be, and re-design
4、parts to include venting later.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N/AAdditional Key Phrase(s): a71 Environmenta71 Flight Equipmenta71 HardwareAdditional Info: Approval Info: a71 Approval Date: 1997-05-05a71 Approval Name: Elijah C. Kenta71 Approval Organization: 421a71 Approval Phone Number: 757-864-3345Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
