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 repeated pattern of light and dark that lets you identify it from a chart or the Admiralty List of Lights. The most common chart abbr...
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 navigation lights show different colours in different directions, called sectors. Sector lights help vessels follow a safe approach line or keep clear of dangers. A white sector ofte...
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...
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