By Zach Pusnik
Aircraft carriers and submarines are more than machines with missions, they are the ocean-going versions of small cities. They are the most serious of machines designed, built, and operated to perform the most serious of tasks. Given their missions and operating environments, deploying applicable and effective maintenance plans are essential to protect the lives of their crew, to maximize their lifecycles, and to secure the safety of our country and allies.
However, maintenance plans are notoriously expensive to develop and maintain. Program offices must work with large amounts of (changing) data, from many contributors with their own preferred style guides, subject maintenance plans to multiple reviewers with their own expertise and preferred methods. So, how does the U.S. Navy ensure the maintenance plans for these assets are efficient, effective, and economical? One effective approach is that they employ Backfit Reliability Centered Maintenance (RCM) as part of their comprehensive maintenance strategy.
Backfit RCM is a methodology used to validate and optimize maintenance tasking contained within a maintenance plan. Backfit RCM accomplishes this by using a structured analysis process combined with operational and failure data to ensure current maintenance tasking is adequately preventing system and/or component failure. The methodology first looks to see if identified systems and components really experience the failure modes that the existing maintenance plans are designed to prevent. Where there is a history of system or component failures, the current tasks are analyzed for applicability and effectiveness. Where failure modes are found to not occur, or if they do not occur in the absence of preventive maintenance, then the corresponding maintenance tasks are deemed unnecessary and are removed from the maintenance plan. This core process of Backfit RCM keeps maintenance plans lean with only applicable and effective maintenance tasks.
To perform Backfit RCM, analysts should gather the following technical information for the system under analysis, as available:
The Backfit RCM process follows a decision tree that buckets decisions into the areas of reliability degradation, task applicability, task effectiveness, and task optimization (refer to MIL-STD-3034A, Appendix D, Figure D-1). Within these buckets, there are seven key steps:
Applying Backfit RCM is a proven way to efficiently review and improve maintenance plans. While the U.S. Navy utilizes this process on its largest and most complex assets, Backfit RCM can be used to improve any formal maintenance plan no matter its size or coverage of systems and components. Follow the Backfit RCM process if you’re looking for a way to ensure your maintenance plan delivers the right maintenance, to the right systems and components, and at the right time.