Answer
The Definition: A Docking Plan is a structural engineering drawing prepared by the shipbuilder and kept on board. It provides the Docking Master with the precise dimensions, hull weight distribution curves, and structural reinforcement details required to set up the dry-dock's concrete and timber keel blocks safely without causing structural deformation or buckling to the ship's bottom plating.
Core Contents of a Docking Plan:
Hull Profile & Half-Breadth Layouts: Detailing the exact flat-of-bottom area, the rise of floor, and the structural dimensions of the keel plate.
Block Placement Coordinates: Specifying the exact spacing and height recommendations for the centerline keel blocks and side docking blocks to distribute the ship's deadweight evenly.
Underwater Hull Openings Matrix: Pinpointing the exact geographic coordinates of all sea chests, echo sounder transducers, speed logs, ICCP reference anodes, and tank bottom drain plugs (dock plugs) so the dock master ensures no supporting block is placed directly on top of them.
Internal Structural Alignment Data: Mapping the exact positions of internal longitudinal girders, transverse bulkheads, and web frames. This ensures the docking blocks are positioned directly beneath these heavily reinforced structural zones to prevent hull indentation.