Sections: [Marine Navigational Lights] [Boat Lights] [Nautical Flags] [International Phonetic Alphabet]
Identification at night of both vessels and the IALA buoyage system involves a standard pattern of marine navigational lights. If planning an entry into a channel from seaward at night, list all IALA buoyage or other fixed lights that are visible during the approach and when within the channel. These will include distant lighthouses, which are identified by their loom as the light sweeps the night sky. The list can include inland features such as radio and television transmitter masts being good navigational aids with their height and warning lights.
The helmsman must preserve his night vision as much as possible to accurately interpret the buoyage marine navigational lights and boat lights of other vessels. This can be done by not using any bright light source in and around the cockpit and using red lights, or very dim white ones below in the galley and navigation area.
The detail of each visible marine navigational light in or out of the channel is contained in nautical almanacs. The attributes of a particular marine navigational light, as given in a published list or on a chart, describes its colour and period and, for some types of beacon, its elevation and range. When identifying each marine navigational light, mark it on the chart with a tick, and as the boat sails past it and leaves it abeam, change the tick to a cross.
Boat lights carried by different types of vessels are usually covered by most almanacs. Basically, most vessels must show a red light to port and a green light to starboard, plus one or more white or coloured boat lights varying on the vessel's size, type and use.
Boat lights must have a visible range of 1 nautical mile for vessels less than 12 m or 39.4 ft. and 2 nautical miles for vessels 12 meters or longer. The required minimum intensity in a vertical sector is from 5 degrees above to 5 degrees below the horizontal.
International Navigation Rules require that sidelights be installed above the uppermost continuous deck. When separate red and green sidelight fixtures are used, the masthead or all-round white light, is located as close as practical to the vessel's fore and aft centerline. The masthead or all-round light must be installed at least 1 m or 3.3 ft above the sidelights. Navigation Lights
The International Regulations for Preventing Collisions at Sea specifies the type, size, layout, arc, and distance of visibility of boat lights used by all vessel types. Various combinations indicate, whether a boat is anchored or under way, under sail or power, or fishing or trawling.
All vessels display basic boat navigation lights and may also display one or more steaming lights. Steaming lights identify whether a vessel is under power or sail, its travel direction, and some indication to its size. Some vessels display a set of extra boat lights indicating that they are engaged doing a particular job or have a specific restriction.
Be familiar with the common light arrangements and check that the yacht’s own boat navigation lights conform to the regulations. When using the engine rather than sailing, display the correct boat navigation light combination for a vessel under power. Incorrect use of boat navigation lights on the yacht may lead to a collision.
Basic Navigation Light White Light - Small dinghies of less than 7m or 23ft under sails or oars are required to carry a torch to show a white light when required.
All-Round White Light - A boat up to 7m or 23ft long, under power and incapable of a speed greater than 7 knots, displays a fixed all-round white light.
Stern and Combined Side Lights - A sailing vessel over 7m or 23ft long displays red and green sidelights, each covering an arc of 112.5°. Under 20m or 65ft, the sidelights may be combined in one lantern at the bow. The white stern light is visible over an arc of 135°.
Masthead Light - Sailing yachts under 20m or 65ft may have combined sidelights and the stern light in a tricolour light at the masthead. The masthead light height offers greater visibility however, a separate stern light and sidelights should be fitted in case of or for use under power, with a steaming light.
Separate Lights - Yachts over 20m or 65ft in length use two separate sidelights and a stern light and are not permitted to display a tricolour masthead light. These all-round, red over green lights are often used on large sailing vessels.
Steaming Lights Combined Lights - A power craft less than 20m or 65ft may have a combined masthead and stern light. The sidelights may be combined at the bow.
Single Steaming Light - Power-driven vessels less than 50m or 160ft long show a masthead steaming light that is visible over a 225° arc and positioned above the sidelights. Over 20m or 65ft, the sidelights and stern lights are separate.
Two Steaming Lights - Power vessels more than 50m or 160ft in length show two masthead steaming lights with the forward light positioned lower than the aft light. Both lights are visible over an arc of 225° with the sidelights and a separate stern light.
Nautical flags and boat navigation lights has largely been superseded by the use of the VHF radio; however, the international code flag signals and the Morse code still remain in daily use. A fundamental knowledge should be gained to interpret nautical flags and their combination, as larger vessels or shore stations may use these methods to send a message. Flags and Accessories Marine VHF Radios and Communications
Learning the International Phonetic Alphabet, in which each letter of the alphabet is assigned a word, is used in radio traffic. It enables names and other words to be spelled out over the radio avoiding confusion and distinguishing between, say, 'F' and 'S', or between 'B' , 'P' and 'D'