Glossary Archive

A term that collectively refers to the three organisations responsible for maintaining maritime navigation aids—such as lighthouses, buoys, and beacons—in the waters surrounding the United Kingdom and Ireland. These organisations ensure safe navigation for all mariners in their respective regions and work together to standardise navigational practices across British and Irish waters. The Three General...

A large foresail that overlaps the mainsail, commonly used on sailing yachts to improve speed and performance in light to moderate winds. A Genoa, also known as a "Genny," is a type of headsail used on sailing vessels, particularly yachts. It is a variation of the jib sail but is significantly larger, often extending beyond...

A measure in marine navigation that quantifies the effect of satellite geometry on the accuracy of position determination. It is a factor used to assess the quality of the satellite configuration in relation to the receiver's position. A low GDOP value indicates good satellite geometry, resulting in more accurate position fixes, while a high GDOP...

Sea area of the Met Office Shipping Forecast. Located in the southeastern North Sea, off the coast of northern Germany and the Netherlands. Covering the bay off Germany’s North Sea coast, German Bight experiences cyclonic winds of Force 4–6 and “boggy” seas due to the shallow shelf. The catastrophic North Sea flood of 1962 breached...

A weather model developed by the National Centers for Environmental Prediction (NCEP) that provides global weather forecasts by simulating the atmosphere using mathematical equations and data from various sources.  The Global Forecast System (GFS) is a numerical weather prediction model that is used to produce forecasts for weather conditions globally. Developed by the National Centers...

A pivoted support that allows an object, such as a compass or a stove, to remain level regardless of the motion of the vessel. A gimbal is a mechanical device consisting of one or more rings mounted on axes at right angles to each other, allowing the supported object to remain level even as the...

In a collision situation, one or more vessels are defined as Give Way. The Give Way vessel should alter its course to concede passage to another vessel. Every vessel directed to keep out of the way of another vessel shall, so far as possible, take early and substantial action to keep well clear.

The vessel whose duty it is to keep clear of another, she should take early and substantial action to avoid a collision

A term that collectively refers to the three organisations responsible for maintaining maritime navigation aids—such as lighthouses, buoys, and beacons—in the waters surrounding the United Kingdom and Ireland. These organisations ensure safe navigation for all mariners in their respective regions and work together to standardise navigational practices across British and Irish waters. The Three General...

A composite material made of a polymer matrix reinforced with fine glass fibres, commonly used in marine applications for its strength, durability, and resistance to corrosion. Glass Reinforced Plastic (GRP), also known as fibreglass, is a widely used material in the marine industry due to its unique combination of properties. It is created by embedding...