Investigation in wind tunnel tests of the aerodynamic characteristics of a hybrid sail, consisting of a slat, a hard sail, and a soft sail was combined with experimental clarification of the interactive effects of plural hybrid sails on deck. We measured the hydrodynamic characteristics of underwater fins for advanced sail-assisted ships in tank tests, and analyzed their effectiveness on steady sailing performance, as well as investigating through wind tests the aerodynamic characteristics of a new hybrid sail that utilizes a deck crane as its boom. The weather routing system we developed for advanced sail-assisted ships showed in calculations for a North Pacific Ocean route that an advanced sail-assisted bulk carrier can cut emission of carbon dioxide by a total of 17.4 percent on the average, compared with a conventional bulk carrier.