Page 82 - Collision Avoidance Rules Guide

vessels, and requires them to keep as near to the outer limit of the
channel or fairway which lies on the starboard side as is safe and
practicable. Rule 25(a) required vessels to keep to the starboard side
of the mid-channel.

Proceeding along the course of a narrow channel

A vessel is only required to keep near to the outer limits on her
starboard side when proceeding along the course of the channel. She
would, of course, be permitted to cross the channel for such purposes
as changing pilots or proceeding to a side channel or berth which lies
on the other side provided that such crossing does not impede
the passage of a vessel which can safely navigate only within the
channel (Rule 9(d)).
Sailing vessels proceeding along the course of the channel are
required to keep to the starboard side so far as practicable. If it is not
possible for them to keep close to the outer limit because of the
direction of the wind they must comply with Rule 9(b).

Keep near to the outer limit
The requirement to keep near to the outer limit will usually mean
that, when the depth of water diminishes from the mid-channel out-
wards to the sides, vessels with shallow draught must keep further to
starboard than vessels of deeper draught. However, vessels are not
expected to put themselves in danger by passing too close to the
shoals, or to make frequent alterations of course in order to keep near
to the outer limit of every part of the channel. They are required to
keep as near to the outer limit as is safe and practicable.
It will not be sufficient to move over to the starboard side when
encountering vessels proceeding in the opposite direction. A vessel is
expected to keep near to the outer limit on her starboard side.

Use of radar
Vessels proceeding along the course of a narrow channel or fairway
should make full use of radar and other navigational equipment,
when necessary, to get to their correct side and to ensure that they are
keeping as near to the outer limit as is safe and practicable. This will
apply especially when the visibility is restricted. Several vessels have
been criticised in the Courts for failing to use radar for this purpose.
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