REG NASA-LLIS-1508--2003 Lessons Learned - Orbital Space Plane - Credibility in Cost& Schedule Estimating - Tools& Models.pdf

1、Lessons Learned Entry: 1508Lesson Info:a71 Lesson Number: 1508a71 Lesson Date: 2003-07-01a71 Submitting Organization: MSFCa71 Submitted by: Lisa CarrSubject: Orbital Space Plane - Credibility in Cost & Schedule Estimating - Tools & Models Abstract: Credibility in cost and schedule estimating is key

2、in convincing stakeholders that a program can execute within resource constraints. Place emphasis on providing credible cost and schedule estimations to stakeholders. Description of Driving Event: The Orbital Space Plane (OSP) Program recognized credibility in cost and schedule estimating and placed

3、 great emphasis on developing credible cost tools and models that produce credible results.Lesson(s) Learned: Credibility in cost and schedule estimating is key in convincing stakeholders that a program can execute within resource constraints. OSP recognized this issue and placed great emphasis on d

4、eveloping credible cost tools and models that produce credible results. Significant lack of clarity exists in operations cost models for human space flight vehicles. Models were being developed and vetted but more work is required. “Smart buyer” technical tools and models require a comparable emphas

5、is. Our government evaluators must be able to independently validate contractors analyses, tools and models.Additionally:a. Human Space Flight Operations Cost Model. Obtaining adequate operations cost estimates was a struggle through-out the OSP program studies. The lack of a cost modeling tool for

6、human flight operations significantly increases the time and effort required to generate costing figures. In addition, it is difficult to provide consistent costing figures through multiple iterations/costing exercises.Provided by IHSNot for ResaleNo reproduction or networking permitted without lice

7、nse from IHS-,-,-b. Government Concept. The government concept role in the requirements analysis cycle (RAC) was clear, but its role in the design analysis cycle (DAC) was unclear.c. Design Participation. Teams of NASA human spaceflight system experts and integrated system analysts should have been

8、formed early enough to collaborate on trade study and requirement development analysis design, in order to assure the relevance of objectives and the validity of assumptions, initializing conditions, and models.d. Operations Cost Model. The OSP program recognized the need for a valid Human Space Fli

9、ght Operations Cost Model to support this and future human space flight programs and had begun development. Operations cost modeling tools are not available.e. OSP Cost Estimating Team. The lack of cost credibility in the Space Launch Initiative (SLI) Program required a fresh approach to providing s

10、upportable, defendable, and credible life cycle cost estimates. Assembling and integrating a team of cost estimators with various backgrounds was part of the process to give credibility to OSP cost estimates.f. Independent External Review of NASA Cost Estimating Processes. The lack of cost credibili

11、ty in the SLI Program required that the government determine, via independent sources, if the best possible cost estimating and analysis practices were being followed on OSP. Recommendation(s): Place emphasis on providing credible cost and schedule estimations to stakeholders. Take the time to creat

12、e a NASA team of smart buyers. A plan for improving the cost models through the involvement of the operations and cost estimating communities is imperative. Review, assess, and develop cost estimating tools and models. The team approach to cost estimating evened out biases and leveraged the experien

13、ce and knowledge that each person brought to the group. Furthermore, organizing the cost credibility approach for OSP into Benchmarking, Process Discipline, and Innovation proved to be an effective way of addressing the problem of cost credibility. All Program life cycle cost estimating tools and pr

14、ocesses should be reviewed through outside assessment. Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-a71 Exploration Systemsa71 Space Operation

15、sa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Communication Systemsa71 Independent Verification and Validationa71 NASA StandardsAdditional Info: Approval Info: a71 Approval Date: 2005-04-12a71 Approval Name: Lisa Carra71 Approval Organization: MSFCa71 Approval Phone Number: 256-544-2544Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-