Optimum trim: Optimum trim refers to a ship’s trim under which the required propulsive power is minimal for the specific operational speed and draft of the vessel.

Load planning: The ship loading plan specifies the loading levels and how the loads should be distributed in different cargo spaces. The load planning should be done by consideration of corresponding regulations but above all the ship stability. The process of loading of a ship is with port’s staff and loading superintendents but the master or chief officer is ultimately responsible for all the loading and unloading operations.

Loading computer: A loading computer system is a computer-based system for the calculation and control of ship loading conditions for compliance with the applicable stability requirements and longitudinal and local strength requirements. The ship-board loading computer system consists of software and an appropriate computer.

Lodicator: The Lodicator is an approved instrument on board which can facilitate the following calculations:

  • Cargo stow plan, underdeck & on deck of all types of cargo.
  • Weights distribution to check deck load not exceeded.
  • Draft, Trim, Stability and Strength calculations.

The pre-stowage plan of the container weights are fed in through a disc supplied by the shore planner, which is a great convenience over manual feeding of thousands of containers, their numbers, weights, ports of loading and destination, and type of cargo, if dangerous, reefer, etc.

Even keel: This refers to ship condition when the draft of a ship fore and aft is the same. In other words, even keel refers to zero trim.

Static trim: This refers to a ship’s trim when the ship is in still water (not moving). In this case, it is the difference between aft and forward drafts; mainly dictated by the ship’s cargo, ballast, fuel on board, etc. distributions.

Dynamic trim: This refers to a ship’s trim when the ship is underway and moving. It is different from static trim due to the ship sinkage phenomena. The ship sinks down relative to the still water level when it is underway, due to its forward movement and environmental effects. The level of sinkage is characterized by a dynamic sinkage at the forward and a dynamic sinkage at the aft of the ship. Normally, the forward sinkage is more than the aft sinkage and is a function of ship speed as well. Dynamic trim thus is static trim plus trim changes due to ship sinkage while underway (MariEMS 2017).