Advanced Maintenance Scheduling

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RCMS™ Architecure

To meet their high standards of system reliability, the Air Force's current engine maintenance practices involve frequent inspections, parts replacements, and re-working of the engines. These frequent maintenance activities correspondingly require a large inventory of spare engines and engine components. Yet, it is not known how much of this cost is truly needed to ensure the same level of reliability and availability.

Critical in reliably maintaining such an inventory is understanding the costs associated with it--a shortcoming of current maintenance practices. What is known is that scheduled downtime often far exceeds unscheduled downtime, policy-driven maintenance events often far overshadow reliability maintenance events, and the downtime per maintenance event and the cost per maintenance event at the aircraft level drives operational availability and, ultimately, total ownership. It has been discovered that traditional maintenance programs are not cost-effective in ensuring the desired levels of reliability and availability due, in part, to the lack of policies, procedures, and decision support tools that would enable the necessary enterprise-level perspective on maintenance planning and scheduling.

KBSI, in an SBIR initiative, is addressing these issues by developing, demonstrating, and successfully deploying a Reliability Centered Maintenance Scheduler (RCMS™) tool and supporting application methodology that will help users maximize propulsion system availability while simultaneously minimizing life cycle costs. The RCMS™ tool encapsulates a reliability-centered maintenance strategy that supports maintenance planning and scheduling such that multiple competing objectives are simultaneously optimized. The RCMS™ methodology considers the overall effects of possible maintenance actions, or the risk of not performing those maintenance actions, on aggregate level metrics like engine availability, performance, and life cycle cost. RCM should ideally seek to support maximized aircraft availability. With this in mind, the RCMS™ technology will establish a view of aircraft engines as part of a propulsion system that is part of an individual aircraft system. Using the products of this effort, users in the depot and field maintenance units will have the visibility and decision support to develop effective engine maintenance plans and schedules in a user-friendly, multi-criteria optimization environment.

The RCMS™ technology has significant commercial potential as well. The technology's convergence of optimization, multi-criteria evaluation, reliability analysis, maintenance task decision-making, and risk analysis could benefit a number of private sector industries like manufacturing and health care.

This material is based upon work supported by the United States Air Force under Contract No. FA8650-05-C-2526.  Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the United States Air Force.