Page 155 - Collision Avoidance Rules Guide

Alterations of course should, in general, be avoided after hearing
a fog signal forward of the beam, unless both the position and move-
ment of the other vessel have been reasonably determined. There
have been many Court decisions to this effect.

Miguel de Larrinaga-Hjelmaren
It is because it is so easy to be deceived by sounds heard in fog that it has
been said in this Court time and time again that it is wrong for vessels, par-
ticularly vessels carrying a lot of headway, to alter course in fog merely on
the faith of a fog signal. I only desire to add that I express that view, not only
with all the force at my command, but with the additional authority of the
Elder Brethren, who have advised me in this case in the same sense as their
predecessors in many cases for generations have advised previous judges in
this court. (Mr Justice Willmer, 1956)
The direction of sound signals may be misleading in fog.

Oakmore-A ras

. . . it is so well known - so absolutely well known - that it is impossible to
rely upon the direction of whistles in a fog, that I do not think any man is
justified in relying with certainty upon what he heard when the whistle is
fine on the bows, like this was undoubtedly, and is not justified in thinking
it is broadening unless he can make sure of it. That is the view I entertain
very strongly, because, if it is well established that the direction of sound in
a fog is a matter of uncertainty, it is no use trying to make it a certainty by
saying you looked at the compass. (Sir Gore11 Barnes, 1906)
The case of Oravia-Nereus, 1907, gives a good illustration of the
danger of altering course without sufficient indication of the other
vessel’s position. In this case the Oravia heard a signal apparently
broad on the starboard bow, so she altered course to port. This action
resulted in collision, whereas if the course had not been changed the
vessels would have passed clear port to port.
It is particularly important that helm action should not be taken
when another vessel is sighted but her course is not known.

Wear-Havbris
It has been said over and over again in this Court that when in a fog you
sight a ship whose direction or course you do not know the worst thing you
can do is to take helm action. (Mr Justice Hill, 1925)
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