Multi-Mission Icebreaker Ship Design Factors Influencing Ice Maneuverability

The United States Coast Guard (USCG) is currently in the detail design phase of the PC2, multi-mission Polar Security Cutter (PSC). This paper discusses ship design factors influencing ice maneuverability considering knowledge gleaned and challenges faced throughout the PSC design process. Capability to perform maneuvers in ice are a function of many design factors which may directly or indirectly influence one another and are integral to the design spiral. Initial designation of design features which strongly affect ice maneuverability begins with a thorough understanding of the Icebreaker’s intended operations, environmental considerations, and design drivers (such as performance areas/requirements) influencing ice maneuverability. The hull form and propulsion system are the most important design features in regard to ice maneuvering capability. Early trade-off analyses and model testing give insight into various design drivers that characterize multi-mission Icebreakers (in contrast to classic Icebreaker designs). Maneuvers of interest include turning in level ice, channel breakouts, and star turns. In operation, ice maneuverability is important to free beset vessels, avoid cumbersome ice formations, and dock at piers. Channel width and edge profile generated by the Icebreaker as well as model testing conservativeness are noteworthy factors to consider for their impact on ice maneuvering.