A decision making model for alternative high-speed ferries

A description is given of a new approach to decision making in the fast ferry market. The approach focuses on the keyissues of passenger satisfaction and design robustness. The attractiveness of competing ferries and therefore the selectionbetween them does not depend solely on clearly defined technical aspects that can be easily quantified and compared, butalso on subjective preferences that vary from one passenger to the other. Another important issue concerns theuncertainty about the variation of external factors during the economic life of the vessel. These include economic andenvironmental factors, such as unpredictable future variations in fuel prices, to which fast ferries are particularlysensitive, or changes in routing with all the related seakeeping and other performance implications. The decision makingmodel focuses on the concept of design robustness by applying an algorithm based on a Taguchi-type approach. This sensitivity analysis allows the identification of the best among alternative designs as the most robust one, in other words the one that would maintain its good performance should external uncontrollable factors vary. The structure of the modelis such that designs of various hull forms and types can be compared and ranked. A case study is presented to illustratethe application of the methodology.