What is required for cargo distribution to apply alternative stability criteria for timber deck cargoes?

For alternative stability criteria to apply to timber deck cargoes, it is essential that the cargo extends longitudinally between superstructures. This is a crucial requirement because the stability of timber deck cargoes can vary significantly based on how they are stowed relative to the ship's structure. When the cargo is distributed longitudinally, it can maintain a more uniform distribution of weight, which is vital for the overall stability of the vessel. This ensures that the weight is effectively balanced and helps in managing the center of gravity, thus contributing to the ship’s stability under various conditions.

The longitudinal extension prevents scenarios where cargo could shift and impact the ship’s stability adversely, especially during maneuvers or changes in sea conditions. By properly distributing the timber cargo between fixed points like superstructures, the risk of listing or excessive heel is minimized, thereby promoting safer navigation and cargo handling.