Glossary Archive

The wind we feel. If the true wind is hitting the boat on the beam or in front of the beam the apparent wind will be situated between the boat wind and the true wind. It is the direction of the apparent wind that determines the angle at which we can point the boat. If...

Appraise – To assess the situation, vessel condition, and environmental factors to inform safe navigation decisions. Plan – To develop a detailed course of action for a voyage, considering route, weather, tides, and safety measures. Execute – To carry out the planned voyage or manoeuvre using appropriate seamanship and navigational practices. Monitor – To continuously observe and evaluate the...

A US-based organisation that provides sailing education, certification, and accreditation for sailing schools and instructors.  The American Sailing Association (ASA) was founded in 1983 to promote safe and competent recreational sailing through standardised education and certification. It offers a structured curriculum covering various skill levels, from basic keelboat sailing to advanced offshore passagemaking. ASA-certified schools...

On the land; or aground

The area or direction behind a vessel, towards the stern. Astern is a nautical term used to describe both a direction and a movement in relation to a vessel. When something is located "astern," it means that it is positioned behind the vessel, towards the stern, which is the rear part of the ship. This...

The phrase "as the crow flies," meaning the most direct route, is believed to originate from the marine world. It refers to crows being released from the crow's nest of a ship to aid navigation in finding the nearest land. However, crows do conspicuously fly alone across open country, but crows do not fly in particularly...

A large, lightweight sail with an off-centre shape, designed for sailing off the wind, typically used to improve downwind performance. An asymmetric spinnaker is a type of downwind sail that combines characteristics of both a traditional spinnaker and a genoa. Unlike a symmetrical spinnaker, it has a distinct luff (leading edge) and leech (trailing edge),...

At loggerheads is a nautical term referring to two ships positioned with their respective loggers (wooden blocks used for securing the ship's rigging) in direct opposition to each other. In a figurative sense, the term describes a situation where two parties are in a state of conflict or disagreement and unable to reach a compromise...

This shape is used to gain the receiver's attention and is used at the beginning of a transmission. The message recipient responds with the Ready to Receive (Flag Semaphore) signal.

A maritime communication system that automatically transmits and receives vessel information such as position, speed, and course to enhance navigational safety. The Automatic Identification System (AIS) is a critical technology used in maritime navigation to improve safety and collision avoidance. It operates through the automatic exchange of data between vessels, shore stations, and other AIS-equipped...