How to prepare for poor visibility and avoid a collision sail safely in fog
Not many of us would happily set sail in fog but sometimes it is unavoidable, and knowing how to avoid collisions is crucial, says Andy du Port
Sir John Harvey-jones, erstwhile chairman of ICI, once said, ‘Planning is an unnatural process; the nicest thing about not planning is that failure comes as a complete surprise rather than being preceded by a period of worry and doubt.’ When you see the fog rolling towards you, it is too late to start planning. Not many of us would happily set sail in fog but sometimes it is unavoidable, either out at sea or as we make our way into harbour.
Sailing in poor visibility – fog, heavy rain, even snow – can be disorientating and worrying but some prior thought and basic preparation will help to keep the heart rate near normal and, vitally, you and your crew safe. With any luck you won’t be in fog for long but while you are, you have two objectives: safe navigation and collision avoidance. In open waters your attention will be on collision avoidance, but closer inshore you will probably be busy dodging other vessels while at the same time keeping yourself in safe water.
There is lots of good advice elsewhere about ‘blind’ navigation, so here I will focus on collision avoidance. This is covered in the Colregs by Rule 19: Conduct of vessels in restricted visibility, which is possibly the most misunderstood rule in the book. The actions you should take to avoid collision are quite different from those when vessels are in sight of one another: there is no ‘give way’ vessel and no ‘stand on’ vessel. Even the usual manoeuvring sound signals don’t apply. In poor visibility your best bet is to avoid all close quarters situations. In other words, keep the opposition at arm’s length rather than nipping under the stern as you might in clear weather. One-mile clearance of a big ship in fog is quite close enough for me. ‘A collision at sea can ruin your entire day’ may not have been said by Thucydides, to whom it is often attributed, but whoever actually said it made an indisputable point.