SCHEDULING SHIP MAINTENANCE JOBS IN MULTIPLE PORTS TO MINIMIZE WORKLOAD FLUCTUATION

Abstract

Surface ships in the Navy require planned and unplanned pier-side maintenance. These maintenance jobs, known as availabilities, are contracted out to private shipyards. Ship maintenance schedules must meet the Navy’s operational requirements and stay within the capacity of the contracted shipyards. At the same time, it is important to minimize workload fluctuation in a port to help private shipyards train and maintain a skilled workforce. Building on recent work that schedules availabilities in a single port to minimize workload fluctuation, this thesis develops a port loading model to minimize workload fluctuation for all regional ports in the Area of Responsibility by allowing some ships to receive maintenance work out of their home ports. Scheduling availabilities across multiple ports simultaneously to level the workload in each port has two additional benefits: First, an increase in the number of eligible companies who can bid on the maintenance job will drive down the cost for the Navy. Second, allowing more flexibility to assign availabilities to different ports has the potential to further level the workload at these ports. In a case study on three ports in the West Coast over a six-year period, we demonstrate the effectiveness of the multi-port loading model.