A presentation is attempted linking the historical development, genera
l design considerations for Small Waterplane Area, Twin-Hull (SWATH) h
ull shapes, the design of a particular SWATH, the Navatek I, and her o
perational experience. The ''carrier vessel'' concept on which the Nav
atek I is based is introduced. Principal dimensions and general arrang
ements are shown. A parametric study of twin-strut SWATH hull forms fo
r a hull of constant displacement is presented in some detail. Stabili
ty and ship motion are discussed and actual data for the Navatek I pre
sented. The overall structural analysis is briefly presented, includin
g the method of analysis for the Navatek I. The SWATH captain's operat
ional experience with the Navatek I during her extensive journeys is r
elated to quite some extent.