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www.sname.org/sname/mt January 2013 of the Canadian waterways. To be built in Italy, this ves- sel is due to enter service in the coming year. A more extreme azimuth propulsor con guration is the heavily reinforced arctic propulsor, designed with reinforcements, redundancies, and fail-safes to ensure safe and e cient operation in the demanding operating conditions of the single- or multi-year ice of the Arctic Sea. e powerful, yet compact propulsors that power the Varandey are examples of this type of unit. Power and speed Research and development into more powerful and e -cient propulsors is ongoing. For years, we have worked on developing more powerful propulsors designed for e -cient operations at speeds of 25 knots and more. As a part of this research and development, we undertook several model tests in open water and ice-basins in a variety of ves- sel con gurations and propulsor sizes. e results of these tests veri ed the projected bene ts of the more developed propulsors and showed several unforeseen bene ts, par- ticularly with CRP propulsors in icy conditions. e research and model tests that weve conducted during this R&D process indicate that this new avail- ability of high-powered CRP propulsors makes certain applications more feasible than before,? says Hannu Jukola, a naval architect specializing in hydrodynam- ics. With the new ECO CRP, we are able to combine a demanding ice-class with high power and a high open water propulsive e ciency. We envision that this would be particularly useful for LNG carriers, cargo vessels, and tankers operating in the Northern Sea Route.? e di erent nature of the CRP propeller ow, com- bined with the fact that a dual-end CRP cannot become clogged or blocked by ice (as ducted propulsors or more traditional CRP propulsors that have their propellers side by side at the rear of the unit can be) make dual-end CRP propulsors a potent tool for ice management, perhaps even more potent than ducted propulsors in some cases. e model tests proved that ice-going vessels could ben- e t both in terms of higher fuel e ciency and higher ice management e ciency from the usage of dual-end CRP propulsors, due both to the inherent e ciency of the CRP technology used and the optimization of the propeller ow with the vessels characteristics. In terms of di erent vessels and applications, the tests showed that this new evolution of the CRP propul- sor technology, which we call ECO CRP, could be used to propel powerful tankers and cargo ships operating in the Northern Sea Route that require ice classi cation for the icy conditions of the route as well as free running e ciency. Currently, these applications have used pull- ing azimuth propulsors, which in comparison to a CRP Scale comparison: Steerprops Pirjo-Riitta Nurmi stands with one of the companys SP 35 CRP propulsors units. Image from a 3-D animation of the new SP 120 ECO CRP propulsor. The dual-end design means the unit cant become clogged or blocked by ice.