Lines plan

The lines plan is the drawing that fully defines a hull’s shape through three mutually consistent orthographic views: the sheer (profile) plan showing buttocks in side view, the half-breadth plan showing waterlines in plan view, and the body plan showing the transverse sections (stations) end-on. Each surface point appears in all three, and fairing means making the three agree at every point so the curves carry no unfair bumps. The lines plan is generated from, and feeds back into, the offsets table that tabulates half-breadths at each station and waterline. It is the master geometric document from which displacement, the form coefficients, the hydrostatics, and the plate development all derive, faired in surface CAD.