Support system for planning of navigation schedule by using tidal current in inland seas

There are many inland seas where have international and domestic sailing routes in the world. They have complicated lay of lands and tidal current. We propose Support System for Planning of Navigation Schedule (SUSPANSE), that utilizes current in these inland seas. SUSPANSE bears the least fuel consumption of ships. The least fuel consumption realizes the preservation of natural environment in these inland seas. In this paper, the objective sea area is the Inland Sea Of Japan (ISJ). The width of ISJ is 30 miles from North and South, and 240 miles from East and West. ISJ has about 3,000 islands, which are scattered, and the current is complicated. Besides, main sailing routes of Japan exist in the ISJ. The estimation of current set and velocity in ISJ is generally to carry out by using Tide Tables of Japan Maritime Safety Agency (JMSA). 13 standard points and 212 semi-standard points of tidal current are prepared in ISJ. However, they are not useful for calculation of tidal current velocity at optional points and time in ISJ. For supplement these lack, JMSA publishes Stream Charts of each sea area in ISJ. Tidal current database is prepared by utilizing the Stream Charts. The tidal current database is made from tidal current information and geographical information, and they are piled up together in the database. Tidal current calculation system (TCCS) can estimate the current velocity at optional point and time in ISJ. When sailing route and departure time are input to SUSPANSE, ship's hours under way is calculated in accordance with the sailing route. SUSPANSE recommends the optimal departure time in this day for shortest hours under The effective of SUSPANSE is confirmed by making comparison between actual hours under way and the output of SUSPANSE.