Page 119 - Collision Avoidance Rules Guide

COMMENT:
The main part of this Rule is identical with Rule 19 of the 1960
Regulations but there is an additional phrase requiring the vessel
with the other on her own starboard side to avoid crossing ahead if
the circumstances of the case admit. As Rule 22 of the 1960
Regulations required every give-way vessel to avoid crossing ahead, if
the circumstances permitted, there is effectively no change concerning
the obligations of the give-way vessel when two power-driven vessels
are crossing so as to involve risk of collision.
The requirement to avoid crossing ahead assumes an even greater
importance under the 1972 Regulations due to the fact that a stand-
on power-driven vessel in a crossing situation is permitted to act at
an earlier stage but must not alter course to port. These restrictions
on manceuvres are intended to reduce the possibility of conflicting
action being taken.
Coastal waters
Rule 15 will normally apply to power-driven vessels crossing in coastal
waters, in the process of rounding buoys or headlands, but in the case
of the Alcoa Rambler-Nore$od, 1949, it was held that the Crossing
Rule did not apply as the two vessels had collided in a congested area
and the stand-on vessel had been constantly changing her course,

Crossing in narrow channels and trafic lanes
Power-driven vessels in a crossing situation in a narrow channel or
traffic lane must normally comply with Rule 15 but all vessels are
required to avoid crossing a narrow channel if such crossing impedes
the passage of a vessel which can safely navigate only within the
channel (Rule 9(d)) and a power-driven vessel of less than 20 metres
in length must not impede the safe passage of a power-driven vessel
following a traffic lane (Rule loci)).
Although vessels proceeding in opposite directions in a bending nar-
row channel may come into a crossing situation Rules 15 and 17 do not
apply. Each vessel must comply with Rule 9(a) and keep as near to the
outer limit which lies on her starboard side as is safe and practicable.
Empire Brent-Stormont
As I understand the principles which apply in narrow channels, it has been
laid down for many, many years that although the crossing rule does from
100