Perspectives on NASA Mission Cost and Schedule Performance Trends[在成本NASA的使命和前景进度绩效趋势](-31).ppt

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1、PerspectivesonNASAMissionCostandSchedulePerformanceTrendsPresentationatGSFCSymposium3June2008DavidBeardenAcknowledgments:ClaudeFreaner,BobBitten,DebraEmmons,TomCoonce©2008TheAerospaceCorporationTypicalQuestionsWhatisthemagnitudeofcostandschedulegrowth?Howreliablea

2、reestimatesintheconceptualdesignstage?Whydoescostgrowthoccur?Whatistherelationshipbetweencost,scheduleand“complexity”?Arethereanyimprovementsthatcanbemadeinestimatingthecostsoffuturedesignconcepts?©2008TheAerospaceCorporationwithincostandschedulewithin100%overrunFort

3、yNASARoboticScienceMissionsExperienced27%Costand22%ScheduleGrowth©2008TheAerospaceCorporationWhileSignificantVariabilityisEvident,forEvery10%ofScheduleGrowth,thereisaCorresponding12%IncreaseinCost©2008TheAerospaceCorporationComparisonofScheduleGrowthDatawithAgencyGu

4、idelines:NASATelescopeMissionsGeneralRuleofThumb1MonthperYearNASA/JPLGuidance1.8MonthperYearFourofSixTelescopeMissionsExceededCommonScheduleReserveGuidelines©2008TheAerospaceCorporationComparisonofScheduleGrowthandSuccessforPlanetaryMissionsvs.Earth-orbitingMissionsD

5、evelopmenttimesforPlanetarymissionslessthanEarth-orbitingmissionsduetoconstrainedlaunchwindowsPlanetarymissionsexperiencedlessschedulesliponaveragethanearth-orbitingmissionsHowever,planetarymissionsfailedorimpairedtwiceasoftenAverageDevelopmentTime©2008TheAerospaceCo

6、rporationTypicalQuestionsWhatisthemagnitudeofcostandschedulegrowth?Howreliableareestimatesintheconceptualdesignstage?Whydoescostgrowthoccur?Whatistherelationshipbetweencost,scheduleand“complexity”?Arethereanyimprovementsthatcanbemadeinestimatingthecostsoffuturedesign

7、concepts?©2008TheAerospaceCorporationHowReliablearetheProjects’EstimatesattheConceptualDesignStageandHowDoesConfidenceProgress?TenMissionsDemonstrateHowAccuracyofProjectEstimatesIncreasesOverTimehoweverCostGrowth,OverandAboveReserves,StillOccursDeepintotheProjectLife

8、Cycle©2008TheAerospaceCorporationInWhatPhaseDoesCostGrowthOccur?GreatestGrowthOccursDuringIntegrationandTest(PhaseD)WhenTryingtoGet