1、Lessons Learned Entry: 0597Lesson Info:a71 Lesson Number: 0597a71 Lesson Date: 1998-07-13a71 Submitting Organization: HQa71 Submitted by: Ludwig E. SchusterSubject: Monitoring of On-orbit Spacecraft Health and Performance During Early Mission Checkout Description of Driving Event: During the critica
2、l initial on orbit operations and checkout phase, ground station personnel did not monitor the Lewis spacecraft continuously for anomalies. This was accepted based on a false belief that the spacecraft had a stable safe-mode that it would switch to automatically if anomalies were not immediately cor
3、rected. (In the Lewis implementation, the safe-mode was neither stable nor robust.) The situation was further exacerbated by the fact the spacecraft was in an interim (low altitude) orbit which had high drag and short on-station communications intervals and for which the designers had not carried ou
4、t modeling.Lesson(s) Learned: Continuous monitoring of spacecraft health is essential during the early orbit and operations checkout phase, lasting typically 30-90 days. This is critical if anomalies are present or if the spacecraft has inherent design, power or orbital parameter limitations that mu
5、st be corrected in real time or near real time in order for the spacecraft to survive.Recommendation(s): Ensure that initial on orbit health monitoring of new spacecraft be continuously undertaken by ground station personnel and that any critical life threatening on orbit anomalies be resolved as ex
6、peditiously as possible. This includes ensuring that this segment of the operations phase has adequate program resources.Evidence of Recurrence Control Effectiveness: N/AProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Documents Related to Lesson: N/A
7、Mission Directorate(s): N/AAdditional Key Phrase(s): a71 Administration/Organizationa71 Ground Operationsa71 Policy & PlanningAdditional Info: Approval Info: a71 Approval Date: 1998-07-28a71 Approval Name: Bill Loewya71 Approval Organization: QSa71 Approval Phone Number: 202-358-0528Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
