1、Lessons Learned Entry: 1205Lesson Info:a71 Lesson Number: 1205a71 Lesson Date: 1999-09-13a71 Submitting Organization: JSCa71 Submitted by: Ken Koby/ Ronald A. MontagueSubject: Rivet Collars Tend to Contribute to Foreign Object Debris Description of Driving Event: During recent Multi-Purpose Logistic
2、s Module (MPLM, S/N FM1) operations, loose debris generated by rivets from the Personnel Access Floor (PAF, S/N 002) was discovered. The suspect Foreign Object Debris (FOD) material are rivet collars that are metallic and approximately 0.3 mm - 5 mm in diameter and weigh approximately .04 grams.Root
3、 cause: It was determined that when the Personnel Access Floor was installed into the MPLM, foot traffic (clean room boots) were snagging the rivet collars and dislodging them. The rivet collars were carefully inspected, it was determined that the rivet collars were not thoroughly ground down flush
4、during manufacturing and the remaining raised material was snagging the clean room garments. An extensive search was conducted in MPLM (FM1) by three technicians using hand held lights; one rivet collar was found. The following day, the MPLM was rotated 180 degrees, a post rotation inspection was pe
5、rformed on the interior of the MPLM and no rivet collars were found. The MPLM is currently in the passive configuration with no racks installed, the Y and Z panels are accessible, the interior of the MPLM has been thoroughly inspected and no rivet collars have been found. This MPLM configuration is
6、the optimum configuration for cleaning and performing inspections. MPLM (FM1) current schedule indicates over a year of ground processing in which interior cleanings and inspections are scheduled, furthermore this anomaly was detected within very short time of GSE installation into the MPLM and it i
7、s highly unlikely that any rivet collars remain in the module. The following MPLM engineering groups were notified: Electrical Power Distribution (EPD), Command & Data Handling(C&DH), Environmental Control and Life Support (ECLS), Alenia KSC representative, Huntsville PAF design group, Boeing and NA
8、SA quality organizations.Lesson(s) Learned: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Selection of parts used in spacecraft must consider all facets of the hardware life cycle including manufacturing and ground operations when assuring their ac
9、ceptability.Recommendation(s): Kennedy Space Center (KSC) problem report SS-GA1-01-324-P001 (CFN04), corrected the problem by removing all the rivet collars from the PAF (S/N 002) panels. Huntsville PAF design team has placed a stop work order on the remaining two PAF sets (S/N 001 & 003) in order t
10、o correct the problem at the manufacturer. At this time, the fix appears to be by replacing the PAF rivets with equivalent collarless rivets. This lesson points out the importance of design and use of any hardware that interfaces with ISS flight hardware. Evidence of Recurrence Control Effectiveness
11、: N/ADocuments Related to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Aircrafta71 Configuration Managementa71 Flight Equipmenta71 Flight Operationsa71 Ground Equipmenta71 Ground Operationsa71 Hardwarea71 Parts Materials & Processesa
12、71 Payloadsa71 Safety & Mission Assurancea71 Spacecrafta71 StandardAdditional Info: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Approval Info: a71 Approval Date: 2002-05-30a71 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-,-,-
