Motion characteristics of the KAIYO

Motion Characteristics of the world\´s largest Semi-Submerged Catamaran (SSC) or Small Waterplane Area Twin Hull (SWATH) type support ship "KAIYO" for underwater research are described. The KAIYO was completed in May 1985 and has successfully operated in various sea conditions including severe sea states of 7 to 8, since the delivery. Because of the unique hull shape which provides small motions and accelerations, it is possible for researchers and crew to achieve their tasks more efficiently and to be engaged in long-term projects. This paper presents the outline of the KAIY0 and her seakeeping performance, referring to the motions and accelerations measured during her actual operation off Japan.