1、Lessons Learned Entry: 0916Lesson Info:a71 Lesson Number: 0916a71 Lesson Date: 2000-05-4a71 Submitting Organization: JPLa71 Submitted by: D. OberhettingerSubject: Inadequate MCO Contingency Maneuver Planning (1999) Abstract: The MCO project declined further consideration of a fifth trajectory correc
2、tion maneuver because it had not been adequately tested. Flight projects should review their operational scenarios and mission timelines for consistency with their mission plans and to verify that all planning and testing necessary to support mission risk management decisions has been completed with
3、 appropriate management review.Description of Driving Event: The root cause of the Mars Climate Orbiter (MCO) mission failure was identified by the JPL and NASA Review Boards as navigation errors caused by the software output that provided compensation for small forces effects to the JPL navigation
4、team (References 1 and 2). The mission plan called for execution of the fifth trajectory correction maneuver (TCM-5), if needed, two days prior to Mars Orbit Insertion (MOI). TCM-5 had not been included in the baseline mission operations timeline. As a result, it had never been tested for flight seq
5、uence compatibility and for mission safety. Furthermore, TCM-5 was not included in operational readiness testing (ORT). Therefore, when the time came to execute TCM-5, the decision represented a major risk item for the MCO project. Because of this high perceived risk just prior to MOI, and the lack
6、of compelling evidence of the need to perform this maneuver, the project declined further consideration of TCM-5.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-refer to D descriptionDReference(s):1. “Report on the Loss of the Mars Climate Orbiter Mi
7、ssion,“ JPL D-18441, JPL Special Review Board, November 11, 19992. “Phase I Report,“ (NASA) Mars Climate Orbiter Mishap Investigation Board, November 10, 19993. “Mars Climate Orbiter Mishap Investigation Board - Phase I Report“, Lesson Learned Number 0641, December 1, 19994. Corrective Action Notice
8、 No. Z66283, MCO-JPL/SRB Finding #4.13:“Risk Management“Additional Key Words: course correction, trajectory error, navigation uncertainty, configuration control, CM, software testing, compatibility testing, peer review, mission planning, mission designLesson(s) Learned: Advanced planning, testing, a
9、nd verification of all identified mission maneuvers and sequences is an essential element of mission risk management.Recommendation(s): Flight projects should review their operational scenarios and mission timelines for consistency with their mission plans and to verify that all planning and testing
10、 necessary to support mission risk management decisions has been completed with appropriate management review.Evidence of Recurrence Control Effectiveness: A JPL Corrective Action Notice was assigned and practices will be modified as appropriate.Documents Related to Lesson: Provided by IHSNot for Re
11、saleNo reproduction or networking permitted without license from IHS-,-,-N/AMission Directorate(s): a71 Exploration Systemsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Configuration Managementa71 Flight Operationsa71 Policy & Planninga71 Risk Management/Assessmenta71 Safety & Mission Assurancea71 Test & VerificationAdditional Info: Approval Info: a71 Approval Date: 2000-10-20a71 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-,-,-
