1.1.1 Half Breadth Plan

The same hull form if it is viewed from top will produce the plan view of the ship. However since the hull shape is complex and unique, the plan view must be made at several waterline planes. Thus Half Breadth Planis a lines drawing that represents the shape of the ship hull looking from top view at every waterlines of the ship. Waterline is the horizontal plane that cut the ship along its vertical axis, thus creating the waterlines curvesas. Waterline is normally equally spaced, although half waterline may also be used at the lower region of the ship. Since the hull is symmetry about its centre line, only half of the hull is shown in this plan. Apart from waterline curves, the deck line curve needs to be drawn on this plan. If the ship has bulwark, chines or / and knuckles lines, these curves have also to be shown in the drawing. In this plan, the grid lines shown are the stations and buttock lines of the ship.