1、Lessons Learned Entry: 1275Lesson Info:a71 Lesson Number: 1275a71 Lesson Date: 1998-05-29a71 Submitting Organization: JSCa71 Submitted by: Ronald MontagueSubject: Foreign Object Debris (FOD) Contamination Control Description of Driving Event: After the STS-83 mission metallic particles were found in
2、 several locations of the SpaceLab module floor. This FOD was determined to be from the Express Rack Flight experiment, which included a Space Station International Standard Payload Rack. The source of the FOD was determined to be metal particles entrapped in inaccessible areas of the rack. All of t
3、he metal particles were trapped in the Spacelab module subfloor so there was no crew exposure to floating metal particles. The incident occurred after Boeing Huntsville had already taken steps to correct the processes that were generating the FOD so there was no impact on the factory operations. Whi
4、le actions to control the FOD in the assembled rack were taken prior to the flight, they were not 100% effective due to the restricted access to the rack interior once the flight experiment was assembled.Based on this incident it is apparent that extraordinary efforts will be required to ensure and
5、maintain the cleanliness of the ISS interior hardware. There are many inaccessible areas where an inspection to ensure “visibly clean“ will require more than a simple visual inspection.Lesson(s) Learned: Foreign Object Debris, once allowed into flight hardware, becomes almost impossible to eradicate
6、 without heroic measuresRecommendation(s): The following process improvements were implemented to ensure the cleanliness of the flight hardware. a) Inaccessible areas, which may trap contaminants in subsequent manufacturing operations, are sealed or provided with access panels, holes, etc. to facili
7、tate cleaning. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-b) Cleaning techniques have been developed based on the specific hardware being cleaned. c) A FOD prevention focal point has been established. d) FOD prevention focal, Materials & Process
8、es, and Quality Assurance approve all FOD-producing operations. e) Areas adjacent to a FOD producing operation are securely protected. f) Tyvek or packaging film is placed below and around any FOD producing operation to catch the fallout. g) A clean room vacuum is run during the operation to catch a
9、ny FOD as it is generated. h) The area and the operators are vacuumed after the operation. i) If there are areas, which are inaccessible after the operation, a vacuum or borescope inspection is performed of these areas to ensure there is no contaminates. The vacuum inspection is performed by putting
10、 a clean room wipe between the nozzle and the hose and vacuuming the area. j) See lesson learned #1205 for a discussion of FOD control throughout the program and hardware life cycle. Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): a71 Explorat
11、ion Systemsa71 Sciencea71 Space Operationsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Flight Equipmenta71 Ground Equipmenta71 Ground Operationsa71 Hardwarea71 Hazardous/Toxic Waste/Materialsa71 Industrial Operationsa71 Parts Materials & Processesa71 Research & Developmenta71 Safety & Missi
12、on Assurancea71 SpacecraftProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Additional Info: Approval Info: a71 Approval Date: 2002-08-20a71 Approval Name: Ronald A. Montaguea71 Approval Organization: JSCa71 Approval Phone Number: 281-483-8576Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
