Otter: an optimized transit tool and easy reference

Abstract

Fuel efficiency is a priority for the Chief of Naval Operations (CNO), as stated in the CNO’s Position Report: 2014. While a number of fuel-saving measures have been implemented in recent years, the effects of operational transit speed on fuel consumption have not been adequately understood as a variable. Ships’ commanding officers use fuel-usage curves to determine the most efficient propulsion-plant speed. Fuel efficiency is typically gauged by maintaining a consistent optimal speed. Often there are combinations of speeds that are more efficient than a constant speed. The transit fuel planner, developed in the Naval Postgraduate School’s operations research department by Brown, Kline, Rosenthal, and Washburn in 2007, calculates speed combinations to achieve fuel savings for a given single ship. This thesis adds additional capacities based upon common principles. We provide an omnibus tool, the Optimized Transit Tool and Easy Reference (OTTER), with two complementary components: Dynamic OTTER and Static OTTER. Dynamic OTTER is a versatile, interactive transit-planning tool for any ship class that accommodates drill scheduling, a critical feature. The second tool, Static OTTER, is a generic, optimal solution to individual ship transit-speed combinations, in the form of a printable reference sheet that can be used independently. These products are being implemented by United States Navy surface ships and will yield significant fuel savings, equating to additional time on station.