The Complete 8th Edition Yachtmaster

Traditional aids to navigation such as buoys, beacons and lighthouses are the signposts of the sea. While most of the ones we see today are of modern construction, many are placed on sites so ancient that no one knows when the first cairn of stones was built there in order that it might be identified from seaward. This is particularly noticeable on the rock-strewn coasts of Scandinavia, where the Vardes certainly date back to Viking days.

Originally, lights and daymarks were erected by private individuals or groups either for their own use, or to encourage merchants to navigate in their local waters. Most of these arrangements are now lost in time, but a few are recorded. The original light on the hill behind St Catherine’s Point on the Isle of Wight was erected by order of the Pope, who threatened ex-communication to the village squire if he failed not only to build it, but also to pay the salaries of the monks who were to stoke the beacon. Being a God-fearing fellow, the squire did the honest thing. If this seems high-handed, it should be borne in mind that the squire’s people were notorious wreckers. The Holy Father finally took exception to their behaviour when a large consignment of wine was spirited away from a ship they had enticed on to the shoals. The fact that this was destined for the communion table probably accounts for their undoing.

Nowadays, lights are established in less colourful circumstances. Indeed, with the arrival of electronic fixing systems, light authorities are coming under increasing pressure to cut back their numbers, thus saving shipowners some of the burden of light dues. Practical seamen are resisting this parsimonious approach, however, and will no doubt continue to do so. GPS and the like are, after all, merely one more in the age-old line-up of aids to navigation. Wonderful though they are, they do not render everything else suddenly obsolete.

There are two basic types of visual aid to navigation: solid structures which may or may not be lit, and floating buoys. The former range from sticks of withy wood sunk in the mud of an obscure creek to mighty towers exhibiting lights that could be seen from space with no more assistance than a good pair of binoculars. Buoys include anything moored to the seabed, from lightships offshore down to a plastic can painted red marking a sand-spit off your neighbour’s dock. They are all important to somebody. Commonsense will decide whether a particular one is of any interest to you.

A lighthouse or a beacon is indicated on the chart by a star which marks its accurate position. Your attention is called to the fact that it is highlighted by a magenta ‘flash’ shaped like a lozenge with one end pointed. The sharp end is hard by the object it refers to. Adjacent to the star is all the charted information about the light. Any further and better particulars, including a physical description of the structure, will be found in the officially published List of Lights.

A light is identified by its so-called characteristics, including the period of its cycle. These are usually arranged so as to be different from any other light in the vicinity. The sequence may be an arrangement of flashes, it could be isophase (in which light and dark periods are equal), occulting (where the light is generally ‘on’, and ‘flashes’ off), or simply fixed ‘on’ (Fig 13.1). The permutations of these are many, but they are generally easy both to spot and relate to on the chart. Colours are also used for identifying lights. Unless otherwise stated, you can assume that a light is white, but red, green and sometimes yellow are used as well. Details of the various abbreviations used by cartographers can be found in Fig 13.1. These are largely self-explanatory, but notice that ‘flashing’ is Fl, while ‘fixed’ is ‘F’. The two are often confused by stressed navigators.

The height of a light is charted in metres (as a small m) or feet (ft), and this height is given above the level of Mean High Water Springs (see Chapter 14). Its luminous range of visibility is stated in miles (as a capital M). Luminous range is the distance that the light would carry in clear air to an observer unhampered by the Earth’s curvature. Whether or not you can see it that far away is another matter altogether, and depends upon the relative heights of the light and your eye.

Fig 13.1 Light characteristics (extract from Reeds Nautical Almanac).

Certain publications refer to the nominal range of lights. This is the luminous range as modified by meteorological visibility of 10 nautical miles. Many larger lights will be visible at greater nominal ranges than 10 miles, even in the assumed limited visibility.

Some lights are only visible within certain angles, owing to their being obscured beyond that by a hill, a headland, or some other feature. This is usually, but not always, noted on the chart.

Certain light structures shine different colours into different sectors of their approaches. This is generally used where a specific danger is present whose sphere of influence is defined by a red or a green sector. The coloured sector light may be independent from the main light of the structure, in which case it is noted as such in the light description (e.g. Fl 5sec 25m 15M FR 12m 5M). Lights of this type are commonplace in Scandinavia where winter pilotage through the inner leads is executed by following from the safe sector of one light into the designated sector of the next, and so on, all the way to the Arctic and beyond.

If you see a light charted as having various colours (e.g. Fl WRG 15s), you will see a single flash every 15 seconds. The colour of the flash is determined by the sector in which you are situated. If the sectors are not defined on your chart, you must refer to your list of lights, your pilot book, or your nautical almanac for details.

Coloured sectors are often used as leading lines into harbours. Typically, the white will take you safely in. A red sector warns that you are to port of the line, while green shows you have wandered to starboard. In some areas, a light shows with greater intensity when you are on the safe line. If the chart indicates an intensified sector, you will definitely see this when you are in it. The extra brightness is unmistakable.

Powerful flashing lighthouses can often be seen below the horizon by virtue of the loom of their light. This sweeps round like a searchlight beam. If conditions are suitable you can identify the characteristics of a loom. Sometimes you can also take a rough bearing, though these must always be treated with caution. Disgracefully, some of the more important British lighthouses have been seriously downgraded in recent years. This is claimed to be because, with the rise of electronics, the mariner no longer requires them to be so powerful, but one cannot help wondering if it is to save money. The looms of such once-mighty lights as Beachy Head will no longer be seen halfway to France on a clear night, as the sweeping flash of Gris Nez fades on the clouds astern. Where a loom can still be found – and mercifully, the French at least seem to have kept their lights at full power – you can sometimes take a rough bearing on it to help confirm your GPS position.

A final warning about lighthouses: you will notice that most structures built within living memory are not situated as high as the terrain immediately behind them might have allowed. On the face of things one would assume ‘the higher the better’, since the geographic range of the light would thus be maximised. The reason that full advantage is not always taken of this is the prevalence of low cloud, which snuffs a light as effectively as turning off the power. If, therefore, you are looking for a light whose elevation is great and which stubbornly refuses to appear, always bear in mind the possibility that it is lost in the cloud.

Many lighthouses and some buoys carry a fog signal, activated when the visibility falls below a critical range. These are highly reassuring to any mariner, particularly a non-electronic one, or one who wisely chooses to seek confirmation of his position from beyond the confines of his 12-volt electrical system.

There are various types of fog signal, listed below. All have their own distinctive sound. They are indicated by type on the chart, which will also show any time sequence, e.g. Horn 60s: one blast on a horn every minute.

Sound travels eccentrically in fog, so that it is sometimes confusing to try to pick up the direction of a signal. When you are motoring, station a crew member on the foredeck if conditions permit, because the engine noise will not help you at all back aft. You might consider stopping the motor from time to time for a listening watch. Taking compass bearings on fog signals is rarely practical, but it is usually possible to home in on one, or to note its changing bearings approximately in relation to the yacht’s head.

Wind direction affects the range of a fog signal dramatically. A powerful siren may blow down the breeze for 6 or 7 miles, while a reed trying to penetrate further than half a mile to windward will usually be unsuccessful. These are the fog signal types most usually found:

Diaphone (Dia) gives a long, drawn-out moan, finishing up with a characteristic grunt. It is often very powerful.

Horn (Horn) gives a steady-pitched sound, varying considerably from one to another.

Reed (Reed) produces a weak and high-pitched sound.

Siren (Siren) is generally higher in pitch than a horn or a diaphone.

Tyfon (Typhon) sounds like a ship’s siren.

Nautophone (Naut) – electronic – produces a high, penetrating note.

Lightships are indicated on the chart by a small ship. The exact position is a diminutive circle at the base of the symbol. The characteristics of the light, which is generally 40 ft (13 m) above sea level, are shown adjacent to this. Light vessels swing to their moorings and carry an anchor light in their forward rigging just as if they were a regular sea-going vessel at anchor. Because of the expense of manning them, these vessels are now almost all automated, and many are being replaced by Lanbies and light floats.

A light float is smaller than a lightship and often carries a less powerful light. If it is an important one, the chart will inform you as to its range and elevation as well as its characteristic light pattern.

A Lanby (Large Automated Navigation Buoy) is exactly what it says it is. It consists of a circular floating platform 40 ft (13 m) in diameter on which is raised a trellis mast with a powerful light 40 ft (13 m) above the water. Lanbies are controlled from shore stations and would seem a sensible replacement for the lightship except that their motion is so extreme that servicing them is an extraordinarily onerous task.

Buoys today can have all sorts of clutter disguising their topmarks. If the light is wrong for recognising the colour, look for the overall shape.

High focal plane buoys are often used to mark offshore dangers, or safe water. These are exactly the same as any other ‘pillar’ buoy, except that they are bigger than those normally used inshore. Some of them have quite powerful lights but even those whose beam can be seen at 7 miles do not have their range listed on the chart, though they may be found in the relevant List of Lights.

In offshore areas of considerable shoaling, ordinary buoys of the larger sizes will be found.

Lateral marks are used to indicate channels. Occasionally one is used singly to show that you must pass to one particular side of it. Colour and shape determine whether a lateral mark is to be left to port or starboard. They may be buoys or beacons, but in either case if they are ambiguous in shape they will have a topmark that is not.

Sadly, all the world does not conform to one arrangement of lateral marks. The North Americans leave red to starboard and green to port going up a harbour, travelling shorewards up a channel or, in the absence of anything more positive, proceeding in a clockwise direction around the continent. In Europe under the IALA A (International Association of Lighthouse Authorities) system, the opposite is standard.

At least it is only colour that is reversed. On both sides of the Atlantic, port-hand buoys are flat topped or can shaped; starboard ones are cones, or ‘nuns’. This means that in the US (IALA B), a distant mark with a triangular topmark whose colour is as yet indeterminate should be left to starboard, as in Europe. As it comes closer it will turn out to be red, while under the IALA A system it would be green.

North Americans remember the colour by the mnemonic Red Right Returning. So long as Europeans remember that, then reverse it for home waters (Red Right Returning to Sea), there is no problem. Starboards are cones in both cases, and ports are cans. ‘Have a can of Port, old chap!’ Personally I like mine in a glass, but there you are.

Throughout the world, special marks are yellow; so are their lights. They can be various shapes, but every effort is made to conform this with the mark’s position in relation to other marks, if this is relevant.

Generally speaking, red marks carry red lights; greens carry green; and yellow are always yellow.

Safe water marks such as fairway buoys are universally red and white vertically striped with a white light, but in North America they flash Morse code ‘A’ while ‘IALA As’ may be isophase, occulting or one long flash every ten seconds.

Isolated dangers are marked in all IALA areas by vertical marks with horizontal black and red bands, with two vertically arranged balls as a topmark. ‘Balls-up’ is the mnemonic for remembering this, which is certainly what you will experience if you ignore the warning it represents. Such marks are lit with a group flash 2, which corresponds to the balls.

Temporary wreck buoys are laid to indicate the position of recent dangerous wrecks. They are vertically striped blue and yellow, with an unmistakable alternating blue and yellow flash. If the wreck remains a hazard, the authority concerned will buoy it with cardinals in due course. Meanwhile, stand well clear.

IALA cardinal marks are shown clearly in Fig 13.2. A north mark stands to the north of a hazard, and so on. Therefore, if you come across, say, a south mark and you cannot find it on the chart to check its relevance to your life, you will be safe if you pass to the south of it.

At first sight, cardinal marks look complicated to remember. Actually they are very easy indeed. The north mark’s topmarks point up, or to the north; the south ones point south. The west topmarks look suspiciously like a bobbin

, so remember, West Winds Wool. If you can’t get along with the home knitting, just think of a Wasp-waisted Woman, which it also looks like if you prefer your ladies without heads. For the classical scholar, the east mark puts one in mind of the letter ‘E’ in a carved inscription, thus ←.

So far so good, but what about the disposition of yellow and black? The answer is that the points of the topmarks point towards the black. Look at the diagram and you’ll see what I mean. The black is all at the top on the north mark, all at the bottom on the south, all in the middle of the Wasp-waisted Woman, and at the outsides of the classical

The lights are white and go round the clock-face: east is at 3 o’clock, and flashes in groups of 3; south is 6 (plus a long one to ensure there is no mistake); west is 9; and north should be 12 but no one could be expected to count that many flashes, so it just keeps going continuously. The IALA cardinal system is one of the greatest bonuses to navigation for many decades. It is easy to operate and utterly unambiguous.

Whether or not you obey the instructions of a marker will depend on your draught and your general intentions, but whenever you see one you should identify its type and check it visually to ensure that it coincides with what you expect from your chart. If you find an anomaly, see it through to the end, or you may live to wish that you had.

Sometimes you can pass the wrong side of a set of lateral buoys in order to avoid close encounters with large vessels, which must treat them conventionally.

A cardinal beacon dried out in the Channel Islands as it does on any spring tide.

SKIPPER’S TIPS	Learn your signposts
Learn your signposts and use them intelligently. We’ve come a long way since the Norsemen built their cairns on the outer skerries of Norway.