APPLICATION OF SWATH/FPS CONCEPT TO A PASSENGER EXCURSION VESSEL DESIGN

The historical development of small waterplane area twin-hull ships is briefly reviewed. The principle advantages of SWATH-type ships with respect to seakindliness and reduction of wave making resistance are discussed. Considerations for hull form optimization leading to improved seakindliness are presented. Special problems in the analytical prediction of ship motion and ship resistance for SWATH/FPS ships are pointed out. The inherent problem of reduced static stability is treated by introduction of the flared pod strut concept, a hull form of rapidly increasing waterplane area and GM above a certain waterline. Resulting design possibilities are illustrated for a 66 ft LOA passenger excursion vessel for Hawaiian waters. Finally other applications for relatively small vessels (less than 800 ton) are enumerated and in part illustrated.