Abstract
At the Akasi Kaikyo and approaches, disasters are happend by small crafts. About 45% of small crafts which made the disasters are stranded near Hira Iso, Yamada Iso, Semento Iso. Collisions and other disasters are occured all over the strait. Many small crafts are sailing under the tidal current, the typical route of them are shown in Fig. 8. Many eastbound crafts adopt the route which cross the strait, many westbound crafts adopt the route along the coast of Akasi.
