Stowage plan for container ships

Stowage plan for container ships or bay plan is the plan and method by which different types of container vessels are loaded with containers of specific standard sizes. The plans are used to maximize the economy of shipping and safety on board.

In order to maximize the economy of handling and shipping of containers on a container ship, stowage plans sometimes known as bay plans, have become essential in the shipping trade. The plans are also vital for safety on board the ship and it is recommended that personnel working on ships are familiar with them. Modern stowage plans are executed by computer programs using mathematical calculations similar to those used for solving complicated Tetris problems. One such system of programs is the MACS3.

The most common and noted type of containers are the 20 feet and 40 feet containers. There are also containers with an extent in height called "High Cube" containers. The fixed exterior dimension of the standard size boxes are:

Container vessels are built to contain as many containers as possible, accordingly the vessels are divided into sections:

The cargo hold and on-deck are the spaces where the cargo, stored in containers, is kept.

On container ships the position of containers are identified by a bay-row-tier coordinate system. The bays illustrate the cross sections of the ship and are numbered from bow to stern. The rows run the length of the ship and are numbered from the middle of the ship outwards, even numbers on the port side and odd numbers on the starboard side. The tiers are the layers of containers, numbered from the bottom and up.

In the example image the position coordinates of the containers are:

In order to stow the cargo on a vessel, planners have specific computer programs to aid them. Planners use ports of call and vessel schedule to adjust vessel's route in the planning program. To plan the stowing the following parameters are essential:

After that, planners get discharge lists/plans in the form of an EDI file (the COPRAR) and send information to the container terminals for all the re-stows (discharging containers and re-loading them) which may be required for completing the discharge process. Planners will also classify the loading data according to the kind of cargo in the containers as well as the size and shape of the containers and their destinations. Each container is marked with a series of numbers and codes to identify the container's operator, specifications and what kind of cargo it may hold. The parameters are:

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