Glossary Archive

A network of cordage rigged to a point on the mast and to a series of points on either side of the boom that cradles and guides the sail onto the boom when the sail is lowered.

The International Maritime Signal Flag Lima. Meaning Stop immediately.If appended by a Numeral Pennant, Latitude (the first 2 digits denote degrees; the last 2 denote minutes.)

Lights positioned to assist entry into harbour or safe passage through a channel. Usually one light above another marks the correct course.

A rope or line with a lead weight attached to its end, traditionally used for measuring water depth and sampling the seabed in nautical navigation. A leadline, also known as a sounding line, is one of the oldest tools in maritime navigation, predating modern depth-sounding equipment such as echo sounders. It consists of a long...

A unit of length, normally equal to three nautical miles.

The RYA Learn to Wingsurf course introduces participants to the basics of wingsurfing. Participants learn how to control the wing, balance on the board, and steer effectively in light winds. The course emphasizes safety, fun, and building confidence. By the end, participants will have the foundational skills needed to progress to wingfoiling or more advanced...

The direction towards which the wind blow

The aft edge of a fore-and-aft sail. This edge runs between the head and clew on many triangular sails and has a strong influence on sail shape and airflow. If it is too tight, the sail may hook and disturb flow; if too loose, it may flutter and wear. Sail controls such as sheet tension,...

Command given by helm when tacking as the bow passes through the wind. Tells the crew to reset the sails on the new course.

A shoreline that lies downwind of a vessel, posing a potential hazard as the wind pushes the vessel towards it. A leeshore is a concept in maritime navigation, referring to a stretch of coast or land that is located in the direction towards which the wind is blowing. When a vessel is near a leeshore,...