1、Public Lessons Learned Entry: 3338Lesson Info:a71 Lesson Number: 3338 a71 Lesson Date: 2010-05-1 a71 Submitting Organization: KSC a71 Submitted by: Annette Pitt Subject: Improve the Constraint System / Identification of Precedence Order for Work Procedures Abstract: Constraints, or the identificatio
2、n of a precedence order for work procedures, are crucial to flight hardware processing. A constraints system has been in place for many years in the Shuttle Program. However, when a new electronic work control system was brought online for Ares I-X processing, a robust and automated way of controlli
3、ng constraints was not provided. As a result, several constraints were missed, and this drove the need to rework constraints, such as opening a closed-out area back up to complete work that was missed. This can even become a safety issue. A system must be put in place when new work control systems a
4、re brought online for the identification of a precedence order for work procedures. Description of Driving Event: Constraints are heavily used in Shuttle processing. A constraint is when one work item must be completed before another can be started. For example, a repair must be completed inside a c
5、avity before the area is closed out for flight. The Space Shuttle electronic work control system automatically identifies constraints, but they are then manually entered onto the work document that needs to be held up. During Ares I-X processing a new electronic work control system, Collaborative In
6、tegrated Processing System (CIPS), was brought online and used. However, little thought was given to handling constraints. The old system was not used, and constraints were manually tracked by Planning & Scheduling with an expectation that the engineer would enter them in the electronic document lat
7、er. (The electronic documents were often not released to the floor until the last day or two before they were worked). Several constraints were missed early in the Ares I-X implementation for Solid Rocket Booster (SRB) processing. The CIPS team is working on an automated method to replace the manual
8、 method. Lesson(s) Learned: Constraints management is critical to safe and efficient hardware processing. If a constraint system is not present, open work may not be completed. Therefore, a robust and automated constraints process is critical. Recommendation(s): Future hardware processing systems sh
9、ould allow engineers to identify which procedure must be worked before others. Evidence of Recurrence Control Effectiveness: N/A Documents Related to Lesson: N/A Mission Directorate(s): a71 Space Operations Additional Key Phrase(s): Provided by IHSNot for ResaleNo reproduction or networking permitte
10、d without license from IHS-,-,-a71 1.Ground support systems a71 1.Launch support systems a71 1.Logistics and maintenance a71 1.Ground processing and manifesting Additional Info: a71 Project: Space Shuttle Program Approval Info: a71 Approval Date: 2010-11-15 a71 Approval Name: mbell a71 Approval Organization: HQ Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-