1、Lessons Learned Entry: 0595Lesson Info:a71 Lesson Number: 0595a71 Lesson Date: 1998-07-13a71 Submitting Organization: HQa71 Submitted by: Ludwig E. SchusterSubject: Misapplication of Heritage Systems, Subsystems and Validation Tools on the Lewis Spacecraft Description of Driving Event: The Lewis imp
2、lementation had a flawed attitude control system (ACS) design and simulation deriving from technically invalid application of a design from an earlier mission. This misapplication ultimately led to the spacecraft failure when the system encountered an untested instability during a “safe hold.“Lesson
3、s) Learned: Use of a proven design system in a new application does not ensure success and does not relieve the design activity from carrying out (independent) technical peer reviews and comprehensive assurance processes and validation.Recommendation(s): Ensure uniform treatment of all systems and
4、subsystems in technical and management reviews regardless of heritage. Require comprehensive independent peer reviews on all subsystems and systems.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AProvided by IHSNot for ResaleNo reproduction or networking permitted wi
5、thout license from IHS-,-,-Mission Directorate(s): N/AAdditional Key Phrase(s): a71 Administration/Organizationa71 Hardwarea71 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-,-,-
