Radar The COLREGS state that the lookout must be kept by all available means, which includes radar. This is especially the case in fog. If you have radar you are obliged to use it when necessary. Listen Under power, a foredeck lookout is better placed to hear sound signals, engines, or bow waves than someone aft near the machinery. In any case, the boat should be slowed down periodically in order to hear better. Noises from ashore can be useful when piloting close in. The writer recalls working up the coast of Norfolk using depth soundings and the regular reports of the shotguns from wildfowlers. Dogs barking on beaches can also supply handy input to the overall picture. Interpreting sound signals Try to note the relative bearing of sound signals from another vessel. It is notoriously difficult to be accurate about this because the mist often seems to distort the direction, but do your best. Expect some discrepancies, but try to determine at least whether it is moving forward, aft or, worse, maintaining a steady bearing.
Collision regulations in fog
It is not enough for a skipper to say, ‘I needn’t remember all the sound signals – I can look them up if I have to.’ In fog, there may not be time to do this before you have proceeded between a tug and her tow and brought your ship to ruin. Safe speed The rules state that in restricted visibility every vessel must proceed at ‘a safe speed’. For a small sailing yacht, this may be rather an academic requirement, but for a power yacht or larger sailing boat it means what it says. The rules are non-specific as to what this speed may be. In the case of a small boat it seems reasonable that a skipper should be able to stop her or manoeuvre her realistically within the limits of the ambient visibility. Add to this the contingency of another vessel looming up ahead on a reciprocal course, and you’ll realise that cracking on is not an option.
Action by vessels not in sight of one another It’s easy to assume that the normal collision rules apply at all times, but in Rule 19, special regulations are laid down for vessels not in sight of one another in or near an area of restricted visibility.
Subsection ‘d’ of this rule deals with collision avoidance using radar alone. Its advice is priceless and ignoring it exceedingly unwise. We cannot do better than reiterate it here:
(‘A vessel which detects by radar alone the presence of another vessel shall determine whether a close-quarters situation is developing and/or risk of collision exists. If so, she shall take avoiding action in ample time, provided that when such action consists of an alteration in course, so far as possible the following shall be avoided: (i) An alteration of course to port for a vessel forward of the beam, other than a vessel being overtaken;
(ii) An alteration of course towards a vessel abeam or abaft the beam.’)
Subsection ‘e’ lays down that unless it has been decided that there is no danger of collision, if you hear another vessel’s fog signal forward of the beam you are to reduce speed to the minimum requirements of steerage and, if necessary, take off all way. In any event, extreme caution is to be the watchword until danger of collision is over.
The practicalities of radar on small craft in fog
The only truly satisfactory way of using radar to monitor collision situations is to have a hand permanently stationed at the screen. An occasional glance does not give the continuity that proper assessment of a variety of targets demands. The facts of life are such that in a typical small vessel there may only be one person qualified or experienced enough to use the equipment. This individual is more often than not the skipper, whose place is better on deck taking an overview and standing by should the need for instant action arise. The only answer is for owners of short-handed yachts and power boats to arrange for at least two people on board to be able to handle the radar effectively.
Strategies for fog
The most seamanlike of all fog strategies is not to be caught out in it, especially at night. Fog in daylight is horrid. At night it seems doubly so, especially in tight waters and in the proximity of traffic – and not without cause. After dark, nothing whatever can be seen in dense fog. Therefore, if you are at sea when fog descends and there is any chance of making a safe haven rather than pressing on, this should receive full consideration. Whether by night or day, the essential options for smaller craft are as follows: • Abort and stay in harbour. A forecast for fog banks
130 | MANUAL OF SEAMANSHIP
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