Page 54 - Collision Avoidance Rules Guide

In areas such as the North Western Atlantic, North Pacific and North
Western Europe where there is a high incidence of fog particular
caution is necessary, but during the hours of darkness watchkeeping
officers should always be mindful of the possibility of the visibility
being restricted, even in areas where fog occurs infrequently, and
should use the radar for the purpose of determining visibility whenever
this seems to be necessary.
In the early morning of the 16th October, 1965, the tanker Almizur
was proceeding towards the Persian Gulf at full speed on a northerly
course off the coast of Oman. The sea was calm and the visibility had
previously been excellent. On the radar display the second officer
observed the echo of another vessel right ahead and assumed that it
was an unlighted dhow as no lights were sighted. When the range
closed to three miles he changed to manual steering and ordered the
helmsman to alter course 40" to starboard. He subsequently realised
that there was fog and rang standby on the telegraph. The echo
was in fact caused by an approaching tanker, the John C. Puppus, of
237 metres length. The two vessels collided causing serious damage.
When the case came to the High Court in London both ships were
found to be at fault in several respects. The Almizur was blamed for
entering the fog at too high a speed and reducing too slowly, also for
keeping a poor radar lookout in mistaking a large ship on an opposing
course for a dhow.

RULE 7
Risk of Collision
(a) Every vessel shall use all available means appropriate to the
prevailing circumstances and conditions to determine if risk
of collision exists. If there is any doubt such risk shall be
deemed to exist.
(b) Proper use shall be made of radar equipment if fitted and
operational, including long-range scanning to obtain early
warning of risk of collision and radar plotting or equivalent
systematic observation of detected objects.

(c) Assumptions shall not be made on the basis of scanty infor-
mation, especially scanty radar information.

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