Category: Ship Stability

Introduction This article explains common ship terms in two groups: the terms for the hull and its dimensions, and the terms for the propeller. Each term has a short definition and, where it helps, what it is used for. Hull Definitions Base Line A line drawn on top of the keel plate, used as a…

Introduction Stability calculations depend on the position of the ship’s centre of gravity (COG). It is measured in three ways: transversely, vertically and longitudinally. The COG is the main factor that governs the list and trim of the ship. List is found from transverse stability, and trim from longitudinal stability. This article collects the main…

Introduction Load lines, also called the Plimsoll mark, show the maximum depth to which a ship may be loaded in different seasons and waters. They keep enough freeboard and reserve buoyancy for the ship to stay safe at sea. The rules come from the International Convention on Load Lines. In the United Kingdom, Samuel Plimsoll…