1、Lessons Learned Entry: 0629Lesson Info:a71 Lesson Number: 0629a71 Lesson Date: 1999-07-20a71 Submitting Organization: ARCa71 Submitted by: Dave ZimmerSubject: Fan Screen/Filter Maintenance Considerations for Space Flight Applications Description of Driving Event: During the STS-90 flight, one of the
2、 experiment habitats located in the shuttle Middeck area experienced a mild over-temperature condition. Post-flight evaluations revealed that the habitats air inlet filter was partially clogged restricting airflow into the cooling system. Human hair, lint, and miscellaneous debris clogged the filter
3、Further investigation revealed that many air filters in the Middeck area are similarly blocked and that most payload developers count on the crew to perform daily cleaning of these filters. In order to minimize the impact of the debris and to allow for proper airflow, several design considerations
4、were identified.Lesson(s) Learned: When designing airflow systems for use aboard the shuttle the following items should be considered for air inlet filters:1. The filters should be designed oversized so that they will still perform satisfactorily when 50% blocked.2. To expedite maintenance, the filt
5、er should be designed to be easily replaced or easily removed to facilitate cleaning.3. If the filter is not designed to be replaced, then it should be sized and designed to facilitate cleaning. a. Filters need to be sized large enough from a human factors standpoint to allow crew members to have (h
6、and or finger) access.b. Filter cleaning should not be based on having the crew use duct tape to adhere to or remove attached debris. This is both inefficient and ineffective.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Recommendation(s): See less
7、on(s) learned.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa71 Sciencea71 Aeronautics ResearchAdditional Key Phrase(s): a71 Flight Equipmenta71 Hardwarea71 Payloadsa71 Research & Developmenta71 Safety & Mission Assurancea71 Test & VerificationAdditional Info: Approval Info: a71 Approval Date: 1999-08-02a71 Approval Name: Anthony Bricenoa71 Approval Organization: N244-30a71 Approval Phone Number: 415-604-1012Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
