Thruster challenge for Portland

The latest addition to United States Lines fleet of cruise ships, the 17-year old Patriot (formerly Nieuw Amsterdam), has completed a major refit at Portland Shipyard, has been re-flagged by the US Coast Guard, and entered service in Hawaii in December. Perhaps the most interesting and technically challenging aspect of the conversion effort was the installation of the ship`s new thrusters. Prior to undertaking the work, the yard used computer simulations to test the suitability of the ship`s existing 750kW thrusters for the conditions in the Hawaiian Islands. The tests revealed that additional thruster power would significantly improve manoeuvrability and safety, especially in outlying ports. However, the installation of new thrusters would not be easy because of the lack of usable space below the waterline, both forward and aft.