Incorporation of tropical cyclone avoidance into automated ship scheduling

Abstract

The U.S. Navy’s Combat Logistics Force (CLF) provides at-sea resupply to U.S. and allied vessels throughout the world. The CLF scheduling system anticipates demand and schedules 45 days in advance to meet that demand. Tropical cyclones (TCs) frequently disrupt these plans, requiring diversions and inefficient steaming speeds. We evaluate the impact of adding anticipated TC positions in an operational planning tool called the Replenishment At Sea Planner. Various scenarios are used to test the impact of different geographic representations of the TC obstacle in CLF operational planning. Open-ocean scenarios explore TC impact in ocean crossings, with no limitations caused by land masses, while near-shore scenarios examine the pinching effect of TC landfall. Shorter distances are traveled by CLF ships in the scenarios when the TC obstacle is forecasted, but the present position is excluded. The recommended TC representation is the 24-hour advanced position, with no extended duration. This representation produces the shortest total travel distances for both the open-ocean and near-shore scenarios.