Page 34 - Collision Avoidance Rules Guide

(i) This definition is similar to Rule l(c)(v) of the 1960 Regulations.
The term ‘under way’ is sometimes used in a restricted sense as
applying to a vessel which is actually moving through the water but
this is not the meaning used in the Rules. Rule 35(a) prescribes sound
signals for a power-driven vessel making way and Rule 35(b) specifies
a different signal for a vessel under way but stopped and
making no way through the water.
A vessel which is lying stopped is, nevertheless, expected to
comply with the Rules of Sections I1 and I11 of the Steering and
Sailing Rules. The following guidance to clarify this point has been
approved by the IMO Maritime Safety Committee:
Clar@cation of the application of the word ‘underway’, Rule 3(i).
‘When applying the definition of the term “underway77 mariners should
also have regard to Rule 35(b) where it is indicated that a vessel may
be underway but stopped and making no way through the water.’
A vessel is only considered to be at anchor when the anchor is
down and is holding. Vessels using an anchor to turn in the river, or
riding to their chains with anchors unshackled, or dredging with the
tide, or dragging their anchors have been held to be under way.

(j) This definition is similar to Rule l(c)(vii) of the 1960 Regulations.
References to the dimensions of a vessel and to the positions of
lights and shapes are now based on metric units. Conversions from
imperial to metric units and rounding off the figures has resulted in
both increases and decreases in the values of ship’s length which
governs the number and type of lights and sound signals required.
For example, 50 metres (164 feet approx.) has been substituted for
150 feet as the minimum length of power-driven vessel for which the
second masthead light is compulsory (Rule 23), and 100 metres
(328 feet approx.) has been substituted for 350 feet as the minimum
size of a vessel at anchor which is required to sound the gong aft in
restricted visibility.
Rule 38(c) gives a permanent exemption from the repositioning of
lights due to the change to metric units.

(k) This definition is exactly the same as Rule I(c)(ix) of the 1960
Regulations.
In Rule 1 1 it is stated that the Rules in Section I1 of the Steering and
Sailing Rules (Rules 12-18) apply to vessels in sight of one another.

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