REG NASA-LLIS-5117-2012 Lessons learned - Specifying Confidence Levels For Requirements Verified By Analysis.pdf

1、Public Lessons Learned Entry: 5117 Lesson Info: Lesson Number: 5117 Submitting Organization: KSC Submitted by: Jenni Palmer Subject: Specifying Confidence Levels For Requirements Verified By Analysis Abstract: For requirements that specify verification via analysis, a required confidence level shoul

2、d be defined as part of the requirement. Many of the Constellation Program Ground Systems requirements were to be verified via analysis (specifically probabilistic analysis), but no required confidence level or success criteria was defined, making it difficult to characterize status relative to the

3、requirements. Description of Driving Event: During requirement status reporting, we were often asked if a requirement should be characterized as green, yellow, or red. This was always a challenge because the requirements language did not specify the required probability of success to characterize a

4、requirement as being green or being met. Lesson(s) Learned: In order to effectively levy requirements, the criteria for success must be clearly defined. Recommendation(s): Include the required success criteria in the requirements language. Evidence of Recurrence Control Effectiveness: N/A Documents

5、Related to Lesson: N/A Mission Directorate(s): Exploration Systems Additional Key Phrase(s): Systems Engineering and Analysis. Systems Engineering and Analysis.Level II/III requirements definition Additional Info: Project: Constellation Approval Info: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Approval Date: 2012-04-05 Approval Name: mbell Approval Organization: HQ Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-