Module 12 of 17
Lighthouses, beacons, and light characteristics used for navigation.
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Visual aids to navigation — lighthouses, beacons, light vessels, and lit buoys — are essential for safe navigation, especially at night and in poor visibility. Understanding light charact...
Every navigational light has a defined character — the pattern of light and dark. The most common types are: Fixed (F) — a continuous steady light. Flashing (Fl) — a single flash repeated...
On a chart, a light is described in a standard format, e.g., 'Fl(2) WR 10s 15m 12M'. This reads: Group flashing (2 flashes), White and Red sectors, period 10 seconds, height 15 metres abo...
Many lights show different colours in different directions (sectors). These sectors are designed to guide vessels on safe tracks. A white sector might indicate the safe approach channel,...
Lighthouses are the most prominent visual aids. Each has a unique combination of colour scheme (daymark), light character, and sometimes a fog signal. They are charted with a star symbol...
Some lighthouses and navigation marks have fog signals — sound signals activated in poor visibility. These include diaphones (two-tone), sirens, horns, and bells. The character of the fog...
There are three distinct types of range quoted for navigational lights, each determined by different factors. Understanding which applies in any given situation is critical for safe pilot...
Identifying a light positively requires matching both its characteristic (colour and flash pattern) and its period (the time for one full cycle). Use a watch to time the interval from the...
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