1、Lessons Learned Entry: 0909Lesson Info:a71 Lesson Number: 0909a71 Lesson Date: 2000-08-01a71 Submitting Organization: GSFCa71 Submitted by: Dave CoolidgeSubject: Satellite Deployments Description of Driving Event: During the launch of the NOAA-K weather satellite there was an anomalous deployment of
2、 the Very High Frequency Real Time Antenna (VRA) and an incomplete deployment of the -Y Deployable Sunshade.The VRA is a two-stage deployment. Phase 1 deploys 76 degrees followed by the Phase 2, which deploys through an angle of 166 degrees. The Phase 1 slowly deployed to only approximately 58 degre
3、es instead of its planned 76 degrees. The Phase 2 deployed its full 166 degrees. This left the VRA mispointed by approximately 18 degrees. However, this mispointing does not affect data recovery via the VRA.The telemetry indicated the -Y sunshade had not fully deployed. The incomplete sunshade deplo
4、yment could not by correlated to other indirect observables, since the -Y deployable sunshade is not required for thermal control in the AM orbit.Lesson(s) Learned: 1. The most likely cause of the incomplete deployment of the VRA was inadequate service loops in the wire harness across the hinge of t
5、he antenna boom mechanism.2. Similarly, the most likely cause of the incomplete deployment of the -Y deployable sunshade was an inadequate service loop in the wire harness between the Instrument Mounting Platform (IMP) and the potentiometer in the deployable sunshade hinge assembly.Recommendation(s)
6、 a71 Review test procedures and hardware for all mechanisms to assure testing is done with the Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-mechanism in the full flight configuration (i.e., test as you fly).a71 Modify procedures and drawings to a
7、ssure adequate service loops are provided in cross hinge cabling.a71 All ground deployment testing should be conducted with the cross hinge wire harness and any insulation in the flight configuration and not redressed after stowage of the deployment mechanism for flight. If any change/redressing of
8、cabling is necessary after deployment testing, conduct a walkout of that deployable before stowage for flight.a71 Deployments/walkouts should be videotaped and mechanisms should be photo-documented in the deployed and final stowed position.Evidence of Recurrence Control Effectiveness: Mechanical AGE
9、 and all related test procedures were modified to include deployment tiger team recommendations.Subsequent satellite testing was performed in flight configuration.Documents Related to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa71 Sciencea71 Space Operationsa71 Aeronautics ResearchAdd
10、itional Key Phrase(s): a71 Flight Equipmenta71 Hardwarea71 Spacecrafta71 Test & VerificationAdditional Info: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Approval Info: a71 Approval Date: 2000-09-18a71 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-,-,-
