The above modified shortest path is only a chain of straight segments. A chain of continuous areas, along the modified shortest path, with margins of safety should be created. The area with the enough navigable width as a margin of safety is an elemental Safe Water. To keep safety margins of passages, the maximum navigable width of each Safe Water was searched. A chain of Safe Waters, which is shown in Fig. 14, was obtained.

　

　

 In order to keep continuity of two passages and prevent a long way of passages, width of the outlet of the passage were set equivalent to width of the inlet of the next. A chain of continuous elemental passages was obtained. A route based on this chain of elemental passages, which keeps center of each passage, was proposed. Fig.15 shows the obtained elemental passages with a proposed route.

　

　

 According to the above-mentioned standard maneuvers, wheel over positions, rudder orders, telegraph orders and their positions were fixed on the above proposed route. Fig. 16 shows a chain of elemental maneuvers and maneuvering orders which was proposed finally. Fig. 17 is an enlarged copy of a part of the planned maneuvers shown in Fig. 16.