Glossary Archive

An Autonomous Underwater Vehicle (AUV) is a self-propelled, unmanned underwater vehicle capable of operating independently without direct human control. AUVs have sensors, navigation systems, and communication devices that allow them to navigate, collect data, and perform various tasks underwater with a high degree of autonomy. These vehicles are commonly used for scientific research, ocean exploration,...

Equipment that allows the boat steer a course automatically using either compass bearing or a course relative to wind direction

An Autonomous Underwater Vehicle (AUV) is a self-propelled, unmanned underwater vehicle capable of operating independently without direct human control. AUVs have sensors, navigation systems, and communication devices that allow them to navigate, collect data, and perform various tasks underwater with a high degree of autonomy. These vehicles are commonly used for scientific research, ocean exploration,...

A term for a saying a boat that has auxiliary power, i.e. an engine

The maximum angle of heel at which a vessel can recover to an upright position without capsizing. The Angle of Vanishing Stability (AVS) is a critical measure of a vessel's seaworthiness and stability, particularly in rough seas. It refers to the point at which a vessel, when heeled over by wind, waves, or other forces,...

Level with the surface of the water which just washes over an object

An inner forestay

Back (backing) describes the wind’s change in direction when it shifts counterclockwise (anti-clockwise). For example, if the wind shifts from north to west to southwest, it is said to be “backing.” This is important for navigation and weather prediction at sea.

To back a sail means to adjust it so that the wind blows on the opposite side from normal, causing the sail to push the boat in the opposite direction. Backing a sail can assist in manoeuvres like tacking, slowing the boat down, or helping steer during tight manoeuvres, such as docking or handling tricky...

The backstay runs from the top of the mast to the stern of the vessel. The backstay supports the mast and in some cases can be adjusted to change the bend in the mast which aids sail trim. On yachts with very large mainsails which would interfere with the backstay, running backstays would be fitted.