The International Regulations for
Preventing Collisions at Sea
With notes by Lee Taylor
CONTENTS
PART A GENERAL
RULE 1 APPLICATION
RULE 2 RESPONSIBILITY
RULE 3 GENERAL
DEFINITIONS
PART B STEERING
AND SAILING RULES
SECTION I CONDUCT OF
VESSELS IN ANY CONDITION OF VISIBILITY
RULE 4 APPLICATION
RULE 5 LOOK-OUT
RULE 6 SAFE
SPEED
RULE 7 RISK
OF COLLISION
RULE 8 ACTION
TO AVOID COLLISION
RULE 9 NARROW
CHANNELS
RULE 10 TRAFFIC
SEPARATION SCHEMES
SECTION II CONDUCT OF
VESSELS IN SIGHT OF ONE ANOTHER
RULE 11 APPLICATION
RULE 12 SAILING
VESSELS
RULE 13 OVERTAKING
RULE 14 HEAD-ON
SITUATION
RULE 15 CROSSING
SITUATION
RULE 16 ACTION BY GIVE-WAY VESSEL
RULE 17 ACTION BY STAND-ON VESSEL
RULE 18 RESPONSIBILITIES
BETWEEN VESSELS
SECTION III
RULE 19 CONDUCT
OF VESSELS IN RESTRICTED VISIBILITY
PART C LIGHTS
AND SHAPES
RULE 20 APPLICATION
RULE 21 DEFINITIONS
RULE 22 VISIBILITY OF LIGHTS
RULE 23 POWER-DRIVEN
VESSELS UNDERWAY
RULE 24 TOWING
AND PUSHING
RULE 25 SAILING
VESSELS UNDERWAY AND VESSELS UNDER OARS
RULE 26 FISHING
VESSELS
RULE 27 VESSELS
NOT UNDER COMMAND OR RESTRICTED IN THEIR ABILITY TO MANOEUVRE
RULE 28 VESSELS
CONSTRAINED BY THEIR DRAUGHT
RULE 29 PILOT
VESSELS
RULE 30 ANCHORED
VESSELS AND VESSELS AGROUND
RULE 31 SEAPLANES
AND WIG CRAFT
PART D SOUND
AND LIGHT SIGNALS
RULE 32 DEFINITIONS
RULE 33 EQUIPMENT
FOR SOUND SIGNALS
RULE 34 MANOEUVRING
AND WARNING SIGNALS
RULE 35 SOUND
SIGNALS IN RESTRICTED VISIBILITY
RULE 36 SIGNALS
TO ATTRACT ATTENTION
RULE 37 DISTRESS
SIGNALS
PART E EXEMPTIONS
RULE 38 EXEMPTIONS
ANNEX I POSITIONING
AND TECHNICAL DETAILS OF LIGHTS AND SHAPES
ANNEX II ADDITIONAL
SIGNALS FOR VESSELS FISHING IN CLOSE PROXIMITY
ANNEX III TECHNICAL
DETAILS OF SOUND SIGNAL APPLIANCES
ANNEX IV DISTRESS
SIGNALS
PART A – GENERAL
Rule
1
Application
(a) These
Rules shall apply to all vessels upon the high seas and in all waters connected
therewith navigable by seagoing vessels.
This means if
it is a boat or ship that can be controlled by a human being and can go away to
sea and come back again, the Rules apply to it, so long as the body of water in
which it currently rests is accessible by water from the sea. This means it
does not apply to reservoirs or lakes, for example, where amateur yachting
might go on, or castle moats, or fishing lakes in which people might use boats.
It does apply to canals, rivers (up to the point where it is too shallow) and
other places not accessible to even fairly small merchant ships.
(b) Nothing
in these Rules shall interfere with the operation of special rules made by an
appropriate authority for roadsteads, harbours, rivers, lakes or inland
waterways connected with the high seas and navigable by seagoing vessels. Such
special rules shall conform as closely as possible to these Rules.
In other
words, special rules made for the aforementioned areas (accessible by and
navigable by seagoing vessels) by the authorities that govern them trump the
IRPCS rules. However, where such rules exist, they can be expected to resemble
these Rules. It is therefore crucial that when proceeding along such areas, the
navigator researches whether such rules exist.
(c) Nothing
in these Rules shall interfere with the operation of special rules made by the
Government of any State with respect to additional station or signal lights,
shapes or whistle signals for ships of war and vessels proceeding under convoy,
or with respect to additional station of signal lights or shapes for fishing
vessels engaged in fishing as a fleet. These additional station or signal
lights, shapes or whistle signals shall, so far as possible, be such that they
cannot be mistaken for any light, shape or signal authorised elsewhere under
these Rules.
This part is
similar to part (b), except that it applies to shapes, lights and whistle
signals, and stipulates that instead of making such signals resemble existing
signals, they should be sufficiently different so as to be impossible to
confuse with existing signals. In short, then it is the opposite of (b), and
applies to signals.
This rule
should be compared with Rule 36, which describes how signals to attract
attention should be impossible to confuse with signals described elsewhere in
the Rules.
(d) Traffic
separation schemes may be adopted by the Organisation for the purpose of these
Rules.
Any traffic
separation scheme that is not adopted by the International Maritime
Organisation does not need to be navigated in the manner described in these
Rules. However, if such a scheme exists that isn’t adopted by the IMO,
the rules describing how to navigate through it consist of ‘special
rules’ made by the government of the appropriate state, and those Rules
should resemble the existing Rules as closely as possible.
(e) Whenever
the Government concerned shall have determined that a vessel of Special
construction or purpose cannot comply fully with the provisions of any of these
Rules with respect to the number, position, range or arc of visibility of
lights or shapes, as well as to the disposition and characteristics of
sound-signalling appliances, such vessel shall comply with such other
provisions in regard to the number, position, range or arc of visibility of
lights or shapes, as well as to the disposition and characteristics of
sound-signalling appliances, as her Government shall have determined to be the
closest possible compliances with these Rules in respect of that vessel.
Certain
vessels (the most common given example is the aircraft carrier) are oddly
shaped, usually because their purpose and function demands it. A vessel of this
design must show signals that most closely resemble the signals that a vessel
is required to show according to the Rules. This is said in a particularly
long-winded way, but it is quite important; it means that the spacing and
arrangement of lights might sometimes deviate from what is expected.
There is a
specific exemption for the need to comply with the positioning of lights and
shapes for WIG craft and seaplanes under Rule 31. This differs from this Rule,
in that it only applies to lights and shapes, and no government sanction is
required.
Rule
2
Responsibility
(a) Nothing
in these Rules shall exonerate any vessel, or the owner, master or crew
thereof, from the consequences of any neglect to comply with these Rules or of
from the neglect of any precaution which may be required by the ordinary
practice of seamen, or by the special circumstances of the case.
There are
many examples where an incident at sea might be avoided by common sense or by
‘the common practice of seamen’. As not every example of what this
might be entail can be described in the Rules, this part serves as a
‘catch all’, which means that if the vessel in which you are in
control of has a collision, even if you were in compliance with all the rest of
the Rules, if you have not acted in accordance with the ordinary practice of
seamen (or taking into account the ‘special circumstances of the
case’), and this was actually relevant, then you would be considered
responsible.
Since failure
to comply with such ordinary practices is considered, according to this part,
to be in contravention of the Rules, such practises can be considered to be a
part of the Rules, and must be complied with, even though they are not stated
within the Rules.
This part can
be considered to include a combination of experience at sea, situational
awareness, and guidance described elsewhere, such as in the international
chamber of shipping bridge procedures guide, or in marine guidance notices.
It can also
be interpreted to mean that if you have a collision, that you are considered
responsible even if you complied with the Rules to the letter (which should, in
theory never happen). Under this (cynical) interpretation, if you have a
collision, it’s because you have failed to act with the ordinary practice
of seamen.
(b) In
construing and complying with these Rules due regard shall be had to all
dangers of navigation and collision and to any special circumstances, including
the limitations of the vessels involved, which may make a departure from these
Rules necessary to avoid immediate danger.
This means,
in a nutshell, that if it is necessary to make a departure from the Rules, that
you should make the departure, and if you do not, the results of failing to
make that departure are yours. Such departures might include alterations of
course for navigational purposes, not the purpose of collision avoidance.
It can also
be interpreted to mean that if you have a collision, that you are considered
responsible even if you complied with the Rules to the letter (which should, in
theory never happen). Under this (cynical) interpretation, if you have a
collision, it’s because you have failed to make a departure from the
Rules when necessary.
Rule
3
General Definitions
For the purpose of these Rules, except where the
context otherwise requires:
(a) The
word ‘vessel’ includes every description of watercraft, including
non-displacement craft, WIG craft and seaplanes, used or capable of being used
as a means of transportation on water.
This part should
be read with reference to Rule 1(a), which states that the rules apply to
vessels upon the high seas and upon any body of water which is connected to the
high seas. Therefore, this rule doesn’t apply to vessels which
aren’t actually in the water, hence a seaplane, whilst flying,
isn’t a vessel.
The rules
also make reference to ‘objects’, for example, in the towing rules
of Rule 24. Objects are not vessels, although they are in the water, because
they are not ‘craft’ because they are not capable of being used as
a means of transportation over water. This distinction is important; buoys,
dracones, and other objects upon which human beings cannot tread are never
vessels, although if people can ride on it, it can be considered a vessel.
A barge that
has no means of self-propulsion can be ridden and so counts as a vessel.
(b) The
term power driven vessel means any
vessel propelled by machinery.
The
aforementioned seaplane, when on the water, is propelled by the rotary action
of its blades. Although these propel the craft by utilising air, not water, the
craft still makes way because it is powered by machinery and thus is still to
be considered a power-driven vessel.
A vessel
under sail which is also utilising a motor is considered a power-driven vessel,
not a sailing vessel, as is mentioned below.
Note that
only power-driven vessels can be considered vessels constrained by their
draught. Any other type of vessel, for example a vessel at anchor, a fishing
vessel, or a vessel not under command, might be any type of vessel, not just a
power-driven vessel.
A
power-driven vessel is still considered a power-driven vessel even when it not
using its engines, that is, when it is stopped and making no way through the
water.
(c) The
term sailing vessel means any vessel
under sail provided that propelling machinery, if fitted, is not being used.
As mentioned
above, a sailing vessel when using propelling machinery is considered a
power-driven vessel.
A vessel that
has both the capacity to propel itself by sail or machinery is considered a
sailing vessel when it uses neither method of propulsion, so sail trumps
machine if stopped and making no way, but if both are being used, and the
vessel is making way under power, then it is considered a power-driven vessel.
(d) The
term vessel engaged in fishing means
any vessel fishing with nets, lines, trawls or other fishing apparatus which
restrict manoeuvrability, but does not include a vessel
fishing with trolling lines or other fishing apparatus which do not restrict
manoeuvrability.
As mentioned
before, any type of vessel can be considered a vessel engaged in fishing, as
long as that is what it is doing. This means it could be a power-driven vessel,
a sailing vessel, or even a rowing boat. However, whatever type of vessel it is,
it is treated as a fishing vessel and only that for the purposes of
lights, shapes and whistle signals if it is fishing in such a way that
restricts its manoeuvrability.
Note that
even though a fishing vessel is defined as a vessel restricted in its manoeuvrability
due to the fact that it is fishing, it is never treated as a vessel restricted
in its ability to manoeuvre, only as vessel engaged in fishing. This point
comes up in later rules.
(e) The
term seaplane includes any aircraft
designed to manoeuvre on the water.
As mentioned
above, the Rules do not apply to aircraft that are not ‘upon the high
seas’, and so whether or not an aircraft is a seaplane, it is only
treated as a seaplane according to the Rules when it is in the water.
Note also
that any type of aircraft is referred to as a seaplane. This means helicopters
and airships are also considered ‘seaplanes’ if they are capable of
landing on the water.
(f) The
term vessel not under command means a
vessel through some exceptional circumstance is unable to manoeuvre as required
by these Rules and is therefore unable to keep out of the way of another
vessel.
The operative
term here is ‘through some exceptional circumstance’. Thus, the
watch cannot have decided to leave the bridge to have a party and throw up the
not under command lights; this term is meant to be interpreted as, ‘if
something that could not have been foreseen occurs to the ship, or, if it was
foreseen, could not have been avoided.’ To reiterate yet again, something
needs to break (usually). Because of the exceptional circumstance, the vessel
has been rendered ‘unable to manoeuvre’ as required by the Rules,
and thus, usually, this must be a result of a steering gear failure, or main
propulsion failure (or the oars could have fallen into the water, or the sail
has been eaten by giant semi-aquatic moths; the rule does not apply exclusively
to power-driven vessels.)
There are
other potential incidents which would leave a vessel not under command. If
there are no officers to maintain a watch, a vessel literally has no-one to
command it, for example, and is thus not under command. This might happen if
there is a fire on board, and all hands are fighting the fire. Or, it might be
that a watch is being maintained, but a vessel cannot manoeuvre because it must
keep the fire on the lee side of the vessel, and thus cannot turn.
This does not
mean that a vessel not under command necessarily requires assistance, and it
does not mean that a vessel not under command is in distress; this is
emphatically illustrated by Rule 27(h).
(g) The
term vessel restricted in her ability to
manoeuvre means a vessel which from the nature of her work is restricted in
her ability to manoeuvre as required by these Rules and is therefore unable to
keep out of the way of another vessel. The term vessels restricted in their ability to manoeuvre shall include but
not be limited to:
The primary
difference between a vessel not under command, as far as the Rules go, is made
clear here; ‘through the nature of her work’ is the operative term.
A vessel which cannot manoeuvre in the manner the rules require because of her
work isn’t unable to alter course or speed because of some exceptional
circumstance, but because of normal circumstance.
Note that the
list that follows is not necessarily an exhaustive list. If a vessel would
otherwise be considered a power-driven vessel or sailing vessel and it cannot
manoeuvre as required by the Rules, then it can be considered a vessel
restricted in her ability to manoeuvre as defined by this Rule, so long as it
displays the appropriate shapes and whistle signals.
(i) a vessel engaged in laying, servicing or picking up a
navigation mark, submarine cable or pipeline;
Such vessels
can be identified by a cable protruding from the bow and/or stern of the ship.
They are most likely following a cable or pipeline that is described on the
chart and will likely provide information regarding their route and activity by
radio in the form of a security announcement.
(ii) a vessel engaged in dredging, surveying or underwater
operations;
Please note
that these types of vessels may present special lights or shapes appropriate
only to this group of vessels restricted in their ability to manoeuvre. This is
described in Rule 27 part (d).
(iii) a vessel engaged in replenishment or transferring persons,
provisions or cargo while underway;
(iv) a vessel engaged in mine clearance operations;
Such vessels
display different lights and shapes to other vessels restricted in their
ability to manoeuvre, as described in Rule 27 part (f). Other vessels are
directed to keep 1000m away from such a vessel, which is
about five and a half cables.
(vi) a vessel engaged in a towing operation such as severely
restricts the towing vessel and her tow in their ability to deviate from their
course.
It is worth
mentioning specifically that vessels engaged in towing or towing alongside are
not necessarily restricted in their ability to manoeuvre; they are treated as
power-driven vessels unless they show the shapes and lights of a vessel
restricted in her ability to manoeuvre.
Vessels
pushing other vessels or objects ahead are not towing vessels, but if doing so
causes the pushing vessel to be restricted in its ability to manoeuvre, then it
can display the appropriate lights, shapes and whistle signals for such a
vessel.
PART B – STEERING AND SAILING RULES
Section
I – Conduct of vessels in any condition of visibility
Rule
4
Application
Rules in this section apply in any condition of
visibility.
This means
both inside and outside areas of restricted visibility, and by day or night.
Rule
5
Look-out
Every vessel shall at all times maintain a proper
look-out by sight and hearing as well as by all available means appropriate in
the prevailing circumstances and conditions so as to make a full appraisal of
the situation and of the risk of collision.
This is
considered by most officers of the watch to be one of the most important rules.
It is assumed that such a look-out shall normally consist of an officer of the
watch plus one watch rating, but that the officer alone may be sufficient
during the day time and in good visibility, and in conditions of restricted
visibility, high traffic, or other hazardous conditions in which to navigate, there
shall be more watch ratings on the bridge and/or the Master.
By ‘all
available means’, usually, this means using the radar, and using it
properly. Proper use of the radar is described in Rule 6 (b), but also
elsewhere in the Rules. It does, of course, include any means appropriate;
since the Rules were published, the use of AIS has become common and this can
also be a useful tool. The Rules allow for the use of radar, and for the
navigation of a vessel without access to radar.
Note that
this rule provides an explanation of why a look-out is to be kept; sufficient
look-out is kept so that the officer who has the con is able to make a full
appraisal of what is going on, and what the risk of collision is at any time,
if any. ‘Situational awareness’ is a buzz-word(s) that it is good
to remember. Look-out should be sufficient to provide enough information to
make informed decisions that prevent collisions.
Rule
6
Safe speed
Every vessel shall at all times proceed at a safe
speed so that she can take proper and effective action to avoid collision and
be stopped within a distance appropriate to the prevailing circumstances and
conditions.
This is also
considered to be one of the most important Rules. It defines the speed at which
a vessel must be travelling *at all times*. In most cases, this is
dependent entirely on the vessel’s manoeuvring characteristics, as
explained later in this Rule. There are some cases, such as in severe
restricted visibility, when one can deduce logically from the Rules certain
maximum speeds.
The officer
on watch must always be able to alter the vessel’s speed in response to
the situation. If this is not possible, then the vessel is not under command
and must display the appropriate lights, shapes, and sound signals.
This Rule
should be considered alongside Rule 5, since hazardous conditions of navigation
not only necessitate lower speeds, but also a greater presence of look-outs.
However, a vessel proceeding at a low speed may require fewer look-outs; for
example, a vessel proceeding at 4 knots when visibility is 4 miles might
require only one look-out in addition to the officer on watch, whereas a vessel
proceeding at 12 knots in the same conditions would definitely require at least
2 watch ratings in addition to the officer.
In determining a safe speed the following factors
shall be among those taken into account:
(a) By
all vessels:
(i) the state of visibility;
As has been
mentioned, in reduced visibility, a vessel should travel at a slower speed, as
described in Rule 19 (b). A vessel isn’t expected to stop when the
visibility is zero; but it is expected to navigate very slowly, and may be
expected to reduce speed to the minimum at which she can be kept on course.
(ii) the traffic density including concentrations of fishing
vessels or any other vessels;
The
assumption is that such vessels are likely to move unpredictably, and because
they are in great number, may move into your path often. Travelling at a lower
speed allows more time to appraise the situation and thus make the correct
decisions when altering course to avoid fishing vessels.
Vessels
travelling at a lower speed relative to one another generally have less need to
avoid each other by as wide a margin, such that at speed of less than ten
knots, only a few cables might need to separate two vessels at the closest
point of approach. At lower speeds, it is safe to avoid fishing vessels by a
smaller distance, which may be the only way to avoid such vessels.
(iii) the manoeuvrability of the vessel with special reference to
stopping distance and turning ability in the prevailing conditions;
This part of
this rule means that vessels need to be able to stop quickly enough to avoid a
collision, and/or turn quickly enough to avoid a collision. Small vessels can
turn on a dime, but large vessels and particular heavy tankers have very long
stopping distances and therefore need to travel at a slower speed, IF they need
to to avoid a collision.
Since the
ability of a vessel to turn is based on how fast the water is flowing over the
rudder, a vessel travelling at a slower speed doesn’t necessarily have a
tighter turning circle, but by travelling at a slower speed, an officer can
allow his or her self more time to appraise the situation before making a
decision in which the ability of the vessel to make turns is a factor.
The ability
of the vessel to reduce its speed, and make a turn, may be influenced by other
factors, including the sea state and other meteorological conditions, the
physical condition of the vessel (these rules apply to ALL vessels, including
vessels that are not under command or restricted in their ability to
manoeuvre), draught, trim, current, and so forth. This is what is meant by
‘prevailing conditions.’
(iv) at night the presence of background lights such as from
shore lights or from backscatter of her own lights;
The
distinction between the navigational lights of other vessels and the lights of
vehicles and buildings ashore is sometimes finer than the seaman would like.
Vessels may approach from the land, and so may not become apparent on radar or
visually in sufficient time for them to be detected and avoided. Proceeding at
a slower speed allows the officer on watch to allow more time for appraisal of
the situation, allowing the officer to detect vessels that might otherwise be
confused with shore lights.
(v) the state of wind, sea and current, and the proximity of
navigational hazards;
A vessel
should travel under sufficient power to keep its course given the available
conditions of wind and current. Especially where there are navigational hazards
nearby, such as shallows and rocks, this may limit the options of the
navigator, and necessitate being not under command or constrained by draught.
Sometimes,
because of such conditions, a ‘safe speed’ may be the highest the
vessel is capable of.
Where there
is a great deal of current and/or leeway, the vessel’s heading and her
course made good may be quite different. This will be exacerbated by steaming
slowly through the water, but it may also be prudent to do so, if navigation
becomes difficult because of these factors.
(vi) the draught in relation to the available depth of water.
Vessels may
sometimes be constrained by their draught. Generally, moving at a slower speed is
recommended in such situations, especially when travelling along narrow
channels, such as a canal. This makes it easier to alter course around tight
corners.
Squat can
have a significant impact on safety of navigation. Where there is little depth
of water relative to draught, a high speed can cause the keel to touch bottom,
causing damage to the keel and/or causing the vessel to run aground. At low
speeds, even when there is very little underkeel clearance, squat will be
minimised. Thus in these conditions, safe speed will be necessarily low.
(b) Additionally,
by vessels with operational radar equipment;
(i) the characteristics, efficiency and limitations of the radar
equipment;
An
understanding of the principles of radar and radar displays is important.
Understanding that radars do not always produce accurate representations of the
locations of objects to be avoided allows the officer on watch to determine
whether or not the radar can be trusted, when determining safe speed, and also
when determining if a higher speed is safe when otherwise a lower speed would
be used, for example, in restricted visibility.
(ii) any constraints imposed by the radar range scale in use;
It is
expected that the radar operator will change range scales to optimise their ability
to appraise the situation. By engaging in radar scanning, the prudent officer
of the watch can obtain early warning of oncoming objects, and by selecting an
appropriate range scale, can obtain accurate and relevant information relating
to identifying risks of collision at close range that immediately need to be
avoided.
Although
here, the range scale in use is described as the determining factor in
determining safe speed, in fact, it will be the other way around; the range
scale shall be adapted to the current speed. A vessel travelling at only 4
knots will not need to set the radar to more than a 6 mile range; a vessel
steaming ahead at 25 knots will not want less than a 6 mile range, off-centred
to maximise the view ahead, and preferably will use a 12 mile range.
(iii) the effect on radar detection of the sea state, weather and
other sources of interference;
Especially
when navigating by radar alone, but also when visibility is sufficient that the
vessel cannot be considered in or near an area of restricted visibility, the
reception of radar signals can be obstructed or even obliterated. Within a 12
mile range, large patches may be covered with rainfall or other large particles
of precipitation or fog, which may obscure vessels within visually and by
radar.
This must be
allowed for when considering safe speed. Although areas of restricted
visibility should prompt a reduction in speed, if radar is compromised (and
there are methods of detecting that this is the case that an experienced
operator will know of) the speed should be reduced further, as it becomes
dangerous to navigate by radar alone.
(iv) the possibility that small vessels, ice and other floating
objects may not be detected by radar at an adequate range;
Ice, wood and
fibreglass are poor radar reflectors. It is not sensible to reduce speed in all
locations, even knowing that such objects might not be detected if they are
present, because yachts, certain fishing boats and icebergs are not likely to
be present in most parts of the sea. However, in areas where they might be
expected, it is prudent to reduce speed, especially in restricted visibility
and at night.
Vessels of
less than 12 metres in length sport masthead lights that are only required to
have nominal ranges of 2 miles, and such vessels have much shorter nominal
ranges for sound signalling appliances. Small objects of wooden or fibreglass
construction are not likely to appear on radar either, so even outside of
restricted visibility, extra look-outs may be required, and it is prudent to
reduce the speed.
(v) the number, location and movement of vessels detected by
radar;
Generally
speaking, when traffic density is high, a safe speed will be lower. However,
using a radar (especially with an ARPA, but otherwise, using radar plotting) it
is possible to identify the exact movements of a large group of vessels, and
thus determine whether or not risk of collision exists more accurately. With
such an ability, less time may be needed to appraise
the situation, so a higher speed is justified.
(vi) the more exact assessment of visibility that may be possible
when radar is used to determine the range of vessels or other objects in the
vicinity.
It is
sometimes difficult to judge the distance of objects observed visually. Atmospheric
conditions can lead to abnormal refraction, and knowing that this is the case,
the wise officer of the watch will determine that a safe speed is lower.
However, whilst abnormal refraction can affect the effective range of radars,
it does not alter the distance at which radar targets are identified.
Therefore, in such conditions, there may be no need to reduce speed, since the
problems caused by such atmospheric conditions are nullified by the use of
radar.
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.
This is
clearly an important rule. It means that, in addition to keeping a proper
look-out by sight and hearing and by radar, the officer on watch shall also
keep watch by whatever other methods are appropriate given the current
situation. This includes using the AIS and any other appropriate equipment
available on the bridge. It also means that if necessary, look-outs should be
put up forward, for example, in severely restricted visibility, since this is
considered an appropriate means to detect risk of collision in that particular
circumstance.
That should
doubt exist assumption that there is a risk of collision should be made is also
very significant; for example, the Rules require (Rule 19 part (e)) that if a
sound signal is heard forward of the beam in restricted visibility, a vessel
shall reduce her speed to the minimum she can be kept on course. According to
this rule, if it is not certain that a sound signal has been heard abaft the
beam in restricted visibility, doubt exists and therefore it shall be assumed
that a risk of collision exists, in which case appropriate action should be
taken (which in this case would mean reducing speed).
Note that if
doubt exists as to whether or not there is a risk of collision, collision
avoidance cannot be undertaken if the location of the source of the risk of
collision cannot be determined.
This part
should mainly be construed as to mean that where it is impossible to be
reasonably certain that a risk of collision does not exist, that a risk of
collision does; therefore, it is better to err on the side of caution.
(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.
The
importance of long-range scanning was described in the notes for Rule 6 (b),
but it should be noted here that the Rules specifically require the radar to be
used if it is present, and for it to be used correctly.
Most people
do not engage in radar plotting with a sheet of paper any more. The equivalent
systematic observation described most should be read as ‘ARPA’.
ARPA should be used if available, and if not, then radar plotting should be.
(c) Assumptions
shall not be made on the basis of scanty information, especially scanty radar
information.
This is a
very general rule, but one that is especially important with regards to
interpreting sound signals and radar information. If clutter is significant,
for example due to inclement weather, then objects may not be detected by radar
at an adequate range, or at all, and if they are, they may be false echoes.
Forearmed with the knowledge that this is the case, then as per Rule 6, the
vessel’s safe speed should be lower; in such conditions, it is forbidden
by the Rules to assume that vessels are not on a collision course, for example.
There are other situations in which scanty information could lead to mistakes;
this rule requires the seafarer to identify when information is
‘scanty’, which means ‘insufficient to base decisions
on’, and to proceed with due caution in the knowledge that it cannot be
relied upon.
(d) In
determining if risk of collision exists the following considerations shall be
among those taken into account:
(i) such risk shall be deemed to exist if the compass bearing of
an approaching vessel does not appreciably change;
This is the
‘iron rule’ of collision avoidance. In conditions outside of
restricted visibility, whether or not risk of collision exists shall be
determined by taking a series of compass bearings. It should not be necessary
to use the radar as the primary means of detecting the presence of other
vessels at range. It is irresponsible to act to avoid collision without taking
a series of compass bearings beforehand.
When using
this method to determine if risk of collision exists, it can be assumed that
the other vessel is sufficiently visible to allow the aspect of the other
vessel to be determined, which is essential to identify what it is doing and
therefore take the appropriate action.
It is
important to note that only when another vessel is approaching does a risk of
collision need to be assumed to exist when there is no bearing change. Vessels
that are at a steady range or that are retreating do not pose a risk of
collision.
(ii) such risk may sometimes exist even when an appreciable
bearing change is evident, particularly when approaching a very large vessel or
a tow or when approaching a vessel at close range.
This short
list is by no means definitive. For example, ‘tow’ can also refer
to vessels being pushed ahead.
This part of
the rule assumes that the bearing is being taken from only one part of the
object. So long as there is some part of the object for which no bearing change
is evident, risk of collision does exist. In other words, in order to determine
if risk of collision exists, take a bearing of both the stern and the bow of
such an object, and if between the bearing change of
those two parts of an approaching vessel there is some part where the bearing
change is zero, risk of collision definitely exists.
Rule
8
Action to avoid collision
It is worth
recalling at this stage that this Rule applies in all conditions of visibility,
that is, in restricted visibility, as well as out of it.
(a) Any
action to avoid collision shall be taken in accordance with the Rules of this
Part and shall, if the circumstances of the case admit, be positive, made in
ample time and with due regard to the observance of good seamanship.
This means
that whenever action is taken to avoid collision in accordance with any other
Rule, whether in or outside of restricted visibility, such an action shall be
undertaken in the manner which is dictated in this rule.
This rule
also states that such action shall be bold, taken early, and shall also be
acceptable to a good seaman. That is, it should not ignore the sensible
precautions that would be undertaken by any competent officer of the watch,
which means that it should take into account weather, the current and sea
state, the depth of water, knowledge of the likely movements of other vessels
and any other considerations that a good officer would normally take into
account.
(b) Any
alteration of course and/or speed to avoid collision shall, if the
circumstances of the case admit, be large enough to be readily apparent to
another vessel observing visually or by radar; a succession of small
alterations of course and/or speed should be avoided.
This
reiterates the ‘positive action’ described in the previous part,
but expands upon it. This part of the rule requires that action should be
readily apparent to another vessel; this means that whilst it is important to
take early action, it may also be important to wait until another vessel can be
reasonably certain of witnessing that such action has been taken.
Note also
that whilst this rule states that making small alterations of course and/or
speed should be avoided, if it turns out that that is the most prudent option,
then this rule requires that it is that action that is taken. For example, it
may be that making a bold alteration of course later will only lead to another
close-quarters situation, whereas a small alteration earlier will eradicate
that problem. The exact wording can be interpreted as, ‘If possible, alterations of course should
be broad, and alterations of speed significant. Making small alterations of
course and altering the speed only a little is not something you should do, if it is possible to avoid it.’
This means
that even if a bold alteration of course is ultimately more of a hassle, and it
would be easier to only make a slight alteration, but the bold alteration is
safe to take, then the bold alteration of course should be taken.
(c) If
there is sufficient sea-room, alteration of course alone may be the most
effective action to avoid a close-quarters situation provided that it is made
in good time, is substantial and does not result in another close-quarters
situation.
This part
essentially acknowledges that it is not always necessary to reduce speed, when
that is an option, so long as by only altering course, close-quarters
situations can be avoided. This is fortunate since shipping companies
don’t particularly like their vessels to slow down!
This part of this
rule announces that alteration of course alone may be the most effective
action. Alteration of speed can be difficult to notice either visually or by
radar, and so should not be the first option considered during action taken to
avoid a collision. The preference should be alteration of course, except where
that is not an option.
(d) Action
taken to avoid collision with another vessel shall be such as to result in
passing at a safe distance. The effectiveness of the action shall be carefully
checked until the other vessel is finally past and clear.
Whenever
action is taken to avoid a collision, such an action shall always be bold
enough to result in passing at a safe distance, in other words, not so close that
a sudden change in conditions will necessarily lead to another risk of
collision developing. The situation should be monitored until it is certain
that there is no longer any risk of collision.
(e) If
necessary to avoid collision or allow more time to assess the situation, a
vessel shall slacken her speed or take all way off by stopping or reversing her
means of propulsion.
When it is
not possible to avoid collision by alteration of course, an officer is required
to reduce speed. However, the officer is also allowed to reduce the speed of
the vessel in order to fully appraise the situation. This part goes hand in
hand with Rule 6, which concerns safe speed. If a vessel is going so fast that
the officer holding the watch cannot determine whether or not there is any
immediate risk of collision, then she is not travelling at a safe speed.
Because this rule allows for slackening speed, it requires it, if necessary.
Note that
outside of restricted visibility, a sound signal accompanies reversing
propulsion; three short blasts on the ship’s whistle, as per Rule 34 (a).
(f) (i) A
vessel which, by any of these Rules, is required not to impede the passage or
safe passage of another vessel shall, when required by the circumstances of the
case, take early action to allow sufficient sea-room for the safe passage of
the other vessel.
It
isn’t made clear what the difference between ‘safe passage’ and ‘passage’ is in the rules. It
may be that allowing another vessel safe passage means to navigate in a way
that does not put it at risk of collision or forces it to navigate into danger,
whilst not impeding the passage of another vessel merely means not forcing it
to alter course or speed at all, but not for the purposes of its safety. It may
be that this specific phrasing refers to rules 9, 10 and 18, which specifically
use the terms passage and safe passage respectively.
There are a
handful of instances in which a vessel is literally referred to as being a
vessel the safe passage of which other vessels are not to impede, as described
in Rule 18 part (d); a vessel constrained by her draught and Rule 9; which
refers to vessels that are navigating within a narrow channel or fairway (from
the point of view of a fishing vessel, a sailing vessel, or vessel less than
20m in length), and vessels which can only navigate within such a narrow
channel or fairway (from the point of view of a vessel which is crossing such a
narrow channel or fairway). In addition, under Rule 10 part (i) and (j),
vessels less than twenty metres in length and sailing vessels must not impede
power-driven vessels in TSSs, and fishing vessels may not impede the passage of
any vessels in TSSs. Vessels not under command or restricted in their ability
to manoeuvre are exempted from this, and other vessels are only required to
avoid impeding the safe passage of vessels constrained by their draught if the
circumstances of the case admit.
Rule 18 also
lays out the general responsibilities between vessels, in particular which
vessels are directed to ‘keep out of the way’ of other vessels.
Although it is not specifically stated that ‘keep out of the way’
or ‘keep clear’ means ‘do not impede the passage or safe
passage of’, it is generally assumed that these meanings are synonymous,
but the difference is significant; a vessel not to be impeded is a vessel
which, through your actions, should not be forced to deviate from its planned
course.
Under this
part of this rule, it is merely stipulated that when taking action to avoid
impeding another vessel, such action shall be as early as is practicably
possible. This resembles part (a) of this Rule, which requires actions made to
avoid collision to be made in ample time. Since action taken to avoid impeding
the passage or safe passage of another vessel is not action to avoid collision,
this part of this rule is required to pronounce the importance of taking action
early.
(ii) A
vessel require not to impede the passage or safe passage of another vessel is
not relieved of this obligation if approaching the other vessel so as to
involve risk of collision and shall, when taking action, have full regard to
the action which may be required by the Rules of this part.
This rule
exists to ensure that there is no possible conflict between this part (f) and
part (a) of this Rule. In other words, a vessel may be required to obey both (a) and (f), not one or the other.
(iii) A vessel
the passage of which is not to be impeded remains fully obliged to comply with
the Rules of this part when the two vessels are approaching on another so as to
involve risk of collision.
This rule
definitely requires vessels the passage of which is not to be impeded to follow
this rule, in other words, they must not impede each other’s passage or
safe passage. This rule refers only to this part, not the whole rule; the
implication is that a vessel the passage of which is not to be impeded is a
vessel that is constrained by its draught, or otherwise is unable to alter
course freely, and thus not able to comply with the other parts of this rule,
such complying with such parts requires the vessel to manoeuvre freely.
Rule
9
Narrow channels
It should be
recalled that these rules apply in all conditions of visibility, but that some
parts of this rule refer to sound signals that are only sounded when two
vessels are in sight of one another.
(a) A
vessel proceeding along the course of a narrow channel or fairway shall keep as
near to the outer limit of the channel or fairway which lies on her starboard
side as is safe and practicable.
It is fairly
easy to remember the way this rule works; it is somewhat analogous to the way a
car is driven on the road in most parts of the world, that is, on the right.
The important
thing to remember is that a narrow channel or fairway may be a canal of some
description, or a much wider body of water with a deep water channel in which
one vessel can safely navigate. A ‘narrow channel or fairway’ is
only considered as such when a vessel has a draught that forbids it from
deviating from her planned passage; in other words, it may be a narrow channel
for one vessel whilst not being so for another. This fact exemplifies the
importance of Rule 8 (f), which dictates the actions of vessels required not to
impede the passage of vessels which are navigating within a narrow channel or
fairway. Not all vessels in proximity to one another are necessarily operating
in a narrow channel or fairway within the context of this Rule.
(b) A
vessel of less than 20m in length or a sailing vessel shall not impede the
passage of a vessel which can safely navigate only within a narrow channel or
fairway.
A vessel
which can safely navigate only within a narrow channel or fairway does not
necessarily have to show the lights or shape for a vessel constrained by its
draught, as dictated in Rule 28, but all vessels including vessels not under command and vessels restricted in their
ability to manoeuvre are required to avoid impeding a vessel which can
safely navigate only within a narrow channel or fairway, even if it is showing
itself to be a vessel constrained by its draught, despite any exemptions
described under Rule 18 part (d), so long as such vessels are less than 20m in
length, or are sailing vessels.
(c) A
vessel engaged in fishing shall not impede the passage of any other vessel
navigating within a narrow channel or fairway.
Note that
vessels engaged in fishing are not merely required to avoid impeding vessels
that can safely navigate only within a narrow channel or fairway; they are
required to avoid impeding all vessels. This rule is somewhat ambiguous,
since a narrow channel for one vessel may be open water for another. However,
under Rule 18, both sailing vessels and power-driven vessels (so long as they
are not under any special condition) are required to keep clear of a vessel
engaged in fishing; this Rule may apply to vessels which are incapable of
keeping clear.
There are
some narrow channels and fairways which are bounded by land or structures
rising above the waterline, for example, canals. Such an area can be considered
a narrow channel by all vessels, in which case, a vessel engaged in fishing can
avoid impeding any other vessel (including other fishing vessels) in compliance
with this Rule.
(d) A
vessel shall not cross a narrow channel or fairway if such crossing impedes the
passage of a vessel which can safely navigate only within such a channel or
fairway. The latter vessel may use the sound signal prescribed in Rule 34(d) if
in doubt as to the intention of the crossing vessel.
This is the
general signal for when a vessel is in doubt as to whether the other vessel is
taking sufficient action to avoid a collision, or if a vessel fails to
understand the intentions or actions of another. It consists of at least five
(but potentially more) short blasts on the ship’s whistle (which can be
remembered by the Morse Code ‘5’, ▪ ▪
▪ ▪ ▪. )
Note that in
this case, the vessel proceeding through a narrow channel or fairway is not
classed as a vessel the passage of which is not to be impeded by the crossing
vessel; the crossing vessel is merely forbidden to cross if such a crossing
would impede the passage of the vessel in the narrow channel or fairway. The
difference is slight and ultimately it means that the crossing vessel must find
another location to cross, or wait for the vessel in the narrow channel or
fairway to pass by.
(e) (i) In
a narrow channel or fairway when overtaking can take place only if the vessel
to be overtaken has to take action to permit safe passing, the vessel intending
to overtake shall indicate her intention
by sounding the appropriate signal prescribed in Rule 34(c)(i). The
vessel to be overtaken shall, if in agreement, sound the appropriate signal
prescribed in Rule 34(c)(ii) and take steps to permit
safe passing. If in doubt she may sound the signals prescribed in Rule 34(d).
The vessel
intending to overtake another vessel shall make the sound signal as prescribed
in Rule 34(c)(i) consisting of two prolonged blasts followed by one short blast
if she intends to overtake on the starboard side, and two prolonged blasts
followed by two short blasts if she intends to overtake on the port side. This
can be remembered as the ‘MIKE’ in the Morse Code (▬ ▬), followed immediately by either ‘ECHO’
in the Morse Code (▪), or ‘INDIA’ in the Morse Code (▪▪).
The sound
signal to be made in agreement, as described in Rule 34(c)(ii),
is one prolonged blast followed by one short blast followed by one prolonged
blast followed by one short blast on the ship’s whistle. This can be
remembered as ‘CHARLIE’ in the Morse Code,
which means ‘affirmative’, ▬ ▪ ▬ ▪.
The signal
prescribed in Rule 34 (d) is the signal for indicating doubt or a failure to
understand the intentions of another vessel, five or more short blasts on the
ship’s whistle, which can be remembered as ‘5’ in the Morse
Code, or ▪ ▪ ▪
▪ ▪.
These sound
signals are only to be made when one vessel can be observed visually by the
other, in other words, outside of conditions of restricted visibility.
If no special
action needs to be taken by the vessel to be overtaken in order for the
overtaking vessel to safely overtake the other, there need be no sound signals.
This rule only applies if the other vessel needs to move out of the way.
Note that the
vessel to be overtaken need not be constrained by her draught or otherwise
confined to a narrow channel; only the overtaking vessel need be so confined
for this rule to apply.
(ii) This
Rule does not relieve the overtaking vessel of her obligation under Rule 13.
Rule 13 is
the Rule which describes overtaking when vessels are in sight of one another.
This rule directs the overtaking vessel to keep out of the way of the vessel
being overtaken, shall not become a crossing vessel as described in Rule 15, and
defines an overtaking vessel as a vessel coming up with another vessel from a
direction more than 22.5° abaft the beam of the vessel being overtaken. It
also states that if there is any doubt as to whether a vessel is being
overtaken, then it shall be assumed that she is and so the overtaking vessel is
directed to act accordingly.
Note,
however, that Rule 9 applies in all conditions of visibility, whereas Rule 13
only applies outside of conditions of restricted visibility.
(f) A
vessel nearing a bend or an area of a narrow channel or fairway where other
vessels may be obscured by an intervening obstruction shall navigate with
particular alertness and caution and shall sound the appropriate signal
prescribed in Rule 34(e).
The sound
signal described in Rule 34(e) is one prolonged blast on the ship’s
whistle, which can be remember as ‘TANGO’ in the Morse Code, ▬.
The response to hearing this sound signal is to reply with one prolonged blast.
Because both
vessels are required to make the same signal when approaching such an obscured
bend, the vessel which makes this signal first can be regarded as the vessel
which will pass through first; this means that the second vessel, knowing that
another vessel will soon appear before her bow, ought to reduce her speed so as
to allow the vessel making this signal to pass ahead safely. This is not a
directive under these Rules, but rather common sense (although common sense
comes under the auspices of good seamanship and/or the common practice of
seamen, and therefore is required by the Rules.)
(g) Any
vessel shall, if the circumstances of the case admit, avoid anchoring in a
narrow channel.
This is a
simple enough Rule to comprehend. This rule clearly exempts vessels that need
to anchor in an emergency. This Rule does not forbid vessels from running
themselves aground, but such a practice is usually frowned upon by the shipping
company!
Rule
10
Traffic separation schemes
(a) This
Rule applies to traffic separation schemes adopted by the Organisation and does
not relieve any vessel under her obligation under any other rule.
This rule
only applies to TSSs adopted by the IMO. Similar unadopted schemes are not
obliged to follow this Rule, but
since such a scheme would constitute a ‘special rule’ made by an
appropriate authority and/or government of any state, vessels are obliged to
follow those Rules under Rule 1. Such special rules would resemble these Rules,
again in accordance with Rule 1.
This Rule is
to be obeyed in all conditions of visibility, and all other Rules must be
obeyed in addition to this rule. Note that for collision avoidance purposes,
quite different Rules apply inside and outside of restricted visibility.
(b) A
vessel using a traffic separation scheme shall:
(i) proceed
in the appropriate traffic lane in the general direction of traffic flow for
that lane;
Vessels
within TSS lanes often fan out or draw closer together when a lane widens or
narrows. Thus, the ‘general direction of flow’ may not follow
parallel lines along a lane. This part of this rule means that vessels should
follow broadly similar courses, not headings, as they proceed
through the lane, appropriate to the shape of the lane and the position in
which the vessels are located.
(ii) so
far as practicable keep clear of a traffic separation line or separation zone;
There are
some exemptions to this part of this rule, described elsewhere in this rule,
particularly (e), but also (c), although it is not explicitly stated in (c)
that separation lines and zones will be crossed.
(iii) normally join or leave a traffic lane at the termination of
the lane, but when joining or leaving from either side shall do so at as small
an angle to the general direction of traffic flow as practicable.
It is not
explicitly stated in this rule that a vessel shall enter or leave a TSS lane on
an angle that is close to the general direction of traffic flow, but this will
be necessary if the vessel is to proceed along the entire lane in such a
manner.
This rule can
be thought of as ‘contradicting’ part (c), and it is quite
different. Vessels using the lane
must leave, if leaving at either side instead of at either end, at as small an
angle to the general direction of flow as possible, but vessels merely crossing the lane must do so with a
heading at right angles to the general direction of traffic flow.
Vessels are,
as stated here, normally not allowed to leave the lane at the sides, but are
allowed to do so as parts (d) and (e) dictate; that is, to avoid immediate
danger, or when en-route to or from a destination, or when to engage in fishing
within a traffic separation zone, or if they are allowed to use the inshore
traffic zone.
(c) A
vessel shall, so far as practicable, avoid crossing traffic lanes but if
obliged to do so shall cross on a heading as nearly as practicable at right
angles to the general direction of traffic flow.
It is
essential to note that this part of this rule requires the crossing vessel to
cross on a heading that is at right angles to the general direction of traffic
flow, not her course made good. This is because a strong current may be acting
against the direction in which the vessel’s passage is plotted; if she
were to make good a course at right angles to the general direction of flow,
her speed vector in that direction would be less than if she were to head at
right angles across the traffic lane.
The quickest
way to cross the traffic lane is to head at right angles across the general
direction of flow. This minimises the amount of time spent in the lane, and
thus reduces the risk of collision.
Note that in
conditions outside of restricted visibility, it is very likely that Rules 15,
16 and 17 will apply, and must still be complied with, as do all Rules.
Although this part of this rule stipulates that the vessel must maintain a
certain heading, she is exempted from complying with this Rule so far as is
necessary to comply with all others, especially in order to avoid a collision.
(d) (i) A
vessel shall not use an inshore traffic zone when she can safely use the
appropriate traffic lane within the adjacent traffic separation scheme.
However, vessels of less than 20m in length, sailing vessels and vessels
engaged in fishing may use the inshore traffic zone.
Because these
types of vessels are allowed to use the inshore traffic zone, they may cross
from a traffic lane across a traffic separation zone or line and thus follow
the rules in part (b) and (c), but should avoid using or crossing the lane if
possible.
This rule
states that vessel engaged in fishing, sailing vessels, and vessels less than
20m in length may use the inshore traffic zone, however, fishing boats that are
not yet engaged in fishing are treated as sailing vessels or power-driven
vessels of their size, and so would be forbidden to enter the inshore traffic
zone if not driven by sail or more than 20m, were it not for the fact that part
(ii) of this part states that vessels en-route to or from a location in the
zone may enter it. In this case, a fishing boat would be en-route to a location
in which she intended to fish.
(ii) Notwithstanding
subparagraph (d)(i), a vessel may use an inshore
traffic zone when en route to or from
a port, offshore installation or structure, pilot station or any other place
situated within the inshore traffic zone, or to avoid immediate danger.
Such vessels
making use of this exemption are most likely following the rules described in
parts (b) and (c).
(e) A
vessel other than a crossing vessel or a vessel leaving a lane shall not normally
enter a separation zone or cross a separation line except:
(i) in cases of emergency to avoid immediate danger;
(ii) to engage in fishing within a separation zone.
Although crossing
vessels and vessels leaving a lane are exempted from the general list of
vessels that are forbidden to enter a separation zone or cross a separation
line, vessels that are enter a separation zone to avoid danger or engage in
fishing can only do so by either crossing a lane or travelling along it for
some distance. Therefore it is prudent for such vessels to cross the lane at a
heading at right angles to the general direction of traffic flow, or to cross
the separation lines at a small to the general direction of traffic flow.
Rules (i) and
(j) may apply here; sailing vessels, vessels engaged in fishing and vessels
less than 20m in length may navigate across the lanes in such a way as to avoid
impeding the passage of vessels using the TSS, but not all vessels that need to
enter a separation zone by crossing or travelling through the lanes are allowed
to navigate in such a way. A vessel not engaged in fishing, but en-route to a
location in a traffic separation zone where it will engage in fishing, propelled
by machinery but more than 20m in length, approaching from an in-shore traffic
zone, is not required by these rules to avoid impeding the passage of vessels
travelling along the lanes of the TSS. She is therefore required to obey part
(c) of this Rule and any other rules, and cannot use an obligation not to
impede the passage of other vessels to ‘dodge’ her requirements to
obey, for example Rule 17, which requires her to stand-on in a crossing
situation. This fact is exemplified by part (a) of this Rule as well.
(f) A
vessel navigating in areas near the terminations of traffic separation schemes
shall do so with particular caution.
Vessels
entering or leaving a lane will do so at the same angle they were following
when travelling in the general direction of flow for that lane. They then are
likely to alter course, so as to head to their next waypoint. A vessel making
an alteration of course for navigational purposes is not obliged to follow
rules that exist to avoid collisions; for example, Rule 17 might require a
vessel to hold its course and speed in a crossing situation, but a vessel
intending to alter course to keep on its intended track before a collision
might occur, hence there is no risk of collision. Vessels near the terminations
of TSS lanes must be cautious of precisely this activity; it is best to avoid
the area if at all possible.
Section
II – Conduct of vessels in sight of one another
Rule
11
Application
Rules in this section apply to vessels in sight of one
another.
Rule
12
Sailing vessels
Note; author
does not understand sailing vessels
(a) When
two sailing vessels are approaching one another, so as to involve risk of
collision, one of them shall keep out of the way of the other as follows:
Although
these rules apply only between sailing vessels, it is necessary for officers on
board other vessels to understand the manoeuvres of sailing vessel in order to
avoid collisions.
Note that in
restricted visibility, there are no specific rules governing sailing vessels;
all vessels are bound to obey Rule 19 when avoiding collisions.
(i) when each has the wind on a different side, the vessel which
has the wind on her port side shall keep out of the way of the other;
When two sailing
vessels have the wind on different sides, the vessel that has the wind on the
port side can make an alteration of course to starboard to avoid a collision,
whilst still keeping her sails full. She is, however, merely directed to keep
out of the way of the other vessel, so she may make an alteration of course to
port.
Her
alteration of course may mean that she has the wind on a different side;
however, after having made such an alteration, there should no longer be any
risk of collision.
(ii) when both have the wind on the same side, the vessel which
is to windward shall keep out of the way of the vessel which is to leeward;
If two
sailing vessels are approaching one another with the wind on the same side, the
vessel to leeward will be fighting against the wind. The vessel to windward
will not be fighting the wind, and so is better able to use the wind to power
her alteration of course. She is therefore directed to take action to keep
clear of the other vessel.
(iii) if a vessel with the wind on the port side sees a vessel to
windward and cannot determine with certainty whether the other vessel has the
wind on the port or on starboard side, she shall keep out of the way of the
other.
If two
vessels have the wind on the same side, then the one to windward keeps out of
the way of the other. If you have the wind on your port side, then you must
keep clear of the other. If you have the wind on your port side but see another
vessel to windward, you would not alter course to keep clear unless she also had
the wind on her starboard side; this rule means that, if doubt exists, you are
directed to keep clear.
It may be
that both vessels have the wind on their starboard side, but cannot see if the
other vessel has the wind on their starboard side. In this situation, neither
vessel can identify whether or not both vessels have the wind on the same or
different sides by observing her mainsail. Under strict interpretation of the
Rules, this means that neither vessel should make an alteration of course
and/or speed to avoid a collision. However, one vessel will know if she is to
windward or leeward; the vessel to windward ought to make an alteration of
course and/or speed to keep clear, as she ought to be able to judge by the
aspect and wind direction whether or not the other vessel has the wind on the
port or starboard side.
(b) For
the purpose of this Rule the windward side shall be deemed to be the side
opposite to that on which the mainsail is carried or, in the case of a
square-rigged vessel, the side opposite to that which the largest for-and-aft
sail is carried.
Rule
13
Overtaking
(a) Notwithstanding
anything contained in the Rules of part B, sections I and II, any vessel
overtaking any other shall keep out of the way of the vessel being overtaken.
This part of
this rule means that despite what directives may exist that command a vessel to
take avoiding action elsewhere in part B, which cover the steering and sailing
rules (including those made after this Rule), a any vessel overtaking any other
vessel is directed to keep out of the way (keep clear) of the vessel being
overtaken.
This is an
important rule, because without this Rule, Rule 14, 15, 16 and 17 would take
precedence, possibly unnecessarily forcing the overtaking vessel to
inconvenience the overtaken vessel or hold her course and speed in a dangerous
manner.
Note that
this rule applies only when one vessel can be sighted from another. In
restricted visibility, Rule 19 applies. Rule 19, part (e), makes a special
consideration for, ‘where it has been determined that a risk of collision
does not exist, every vessel which hears apparently forward of her beam the fog
signal of another… shall reduce her speed to the minimum at which she can
be kept on her course.’ An example of such a situation is where one
vessel is about to overtake another.
Rule 19 (d)
(i) also makes an exception for a situation in which one vessel is overtaking
another; in this instance, it is acceptable to alter to port for a vessel
forward of the beam, so long as that vessel is being overtaken.
It is worth
remembering that an ‘overtaking situation’ only exists in the rules
when vessels can visually observe one another. One vessel might overtake
another in restricted visibility, but Rule 13 is not to be obeyed.
This rule
applies to sailing vessels, overruling the actions required of sailing vessels
in Rule 12.
This Rule
also applies when Rule 9 part (e) applies, which is when one vessel is
approaching another so as to overtake in a narrow channel or fairway, for which
Rule 34 part (c) also applies.
(b) A
vessel shall be deemed to be overtaking when coming up with another vessel
from a direction more than 22.5°
abaft her beam, that is, in such a position with reference to the vessel
she is overtaking, that at night she would be able to see only the sternlight
of that vessel but neither of her sidelights.
(c) When
a vessel is in any doubt as to whether she is overtaking another, she shall
assume that this is the case and act accordingly.
During the
day, it may be difficult to determine the relative aspect of another vessel. A
crossing situation may resemble an overtaking situation. If there is any doubt,
she shall assume that she is overtaking.
She may not
be able to tell whether or not she is moving faster than the vessel to be
overtaken, but she can only be considered an overtaking vessel when she is; if
there is any doubt, she shall, under this rule, assume that she is.
It is
conceivable that, under this Rule, a vessel may act as an overtaking vessel
when she might actually be a stand-on vessel or a give-way vessel as described
by rules 16 and 17. In this case, by acting as an overtaking vessel, the vessel
intending to be overtaken may be confused by the actions of the overtaking
vessel. For this reason, according with Rule 8, such action should be made
earlier rather than later. A vessel confused by the actions of the other may
make the sound and perhaps light signal described in Rule 34, that is, five or
more short blasts on the ship’s whistle, and perhaps in addition, five or
more flashes with a light signalling appliance.
(d) Any
subsequent alteration of the bearing between the two vessels shall not make the
overtaking vessel a crossing vessel within the meaning of these Rules or
relieve her of the duty of keeping clear of the overtaken vessel until she is
finally past and clear.
By crossing
vessel, this part of this Rule refers to Rule 15. It may be that due to part
(c) of this Rule, a crossing vessel may act as an overtaking vessel, but if she
does, she shall ensure that there is no risk of collision after her action, in
accordance with this part of this Rule.
She may not
becomes a crossing vessel after overtaking another vessel, but this does not
mean that she shall be forbidden from passing ahead of another vessel if she is
sufficiently ahead of her that there is no risk of collision. A crossing
situation only exists when two vessels are approaching one another in such a
way as for there to be a risk of a close-quarters situation developing, so long
as such a situation cannot be considered a head-on situation or an overtaking
situation.
Rule
14
Head-on situation
(a) When
two power-driven vessels are meeting on reciprocal or nearly reciprocal course
so as to involve risk of collision each shall alter her course to starboard so
that each shall pass on the port side of the other.
This is often
known as passing ‘port to port’ or ‘red to red’. This
part of this rule only applies to power-driven
vessels. It also only applies when two vessels are in sight of each other.
Often, power-driven vessels are considered other types of vessel according to
the Rules. Where special avoiding action is necessary in the case of such
vessels, as described in Rule 18, which governs the responsibilities between
vessels, his Rule shall be ignored.
Most of the
time, when directed to keep clear of another vessel, especially when two
vessels are meeting in a reciprocal manner such as this, the convention to
alter course to starboard is maintained. This is for two main reasons; firstly,
in order to keep the starboard side free to make this very manoeuvre, and
secondly, because the other vessel will most likely expect this very behaviour.
(b) Such
a situation shall be deemed to exist when a vessel sees the other ahead or
nearly ahead and by night she could see the masthead lights of the other in a
line or nearly in a line and/or both sidelights and by day she observes the
corresponding aspect of the other vessel.
In practice,
this will seldom happen. Although it is quite common for head-on situations to
occur, as different vessels share shipping lanes, for two vessels to approach
one another so as to present to each other both their sidelights is rare.
Additionally,
currents may force a vessel’s heading to vary significantly from her
course. Observing by sea-stabilised radar alone, an officer on watch might note
a head-on situation developing although if observing visually by these terms,
she would not necessarily note it.
For these
reasons, it is worth noting that a head-on situation is deemed to exist under
the circumstances described, but this does not preclude the possibility that
such a situation may exist despite these circumstances not being observed. The
sole criterion should be that, as described in part (a), both vessels are
meeting on reciprocal or nearly reciprocal courses. What this is exactly is
open to interpretation, but it differentiates a head-on situation from a
crossing situation.
In a crossing
situation, the give-way vessel should normally alter to starboard, and when
taking emergency avoiding action, the stand-on vessel should avoid making an
alteration of course to port, in accordance with the requirements of Rules 16
and 17. This means that it is not dangerous to take action as if in a head-on
situation, so long as it appears that vessels are in a head-on situation, even
if they might more properly be considered to be in a crossing situation.
(c) When
a vessel is in any doubt as to whether such a situation exists she shall assume
that it does exist an act accordingly.
As mentioned
in the notes for part (b) of this Rule, doubt may exist as to whether or not a
head-on situation is developing, but the alternative is for a crossing
situation to exist. This part of this rule requires an officer in doubt to err
on the side of ‘head-on’, which in any case will lead to a safe
course of action that prevents collision.
Rule
15
Crossing situation
When two power-driven vessels are crossing so as to
involve risk of collision, the vessel which as the other on her own starboard
side shall keep out of the way and shall, if the circumstances of the case
admit, avoid crossing ahead of the other vessel.
This rule is
the first of three rules, 15, 16 and 17, that govern actions in a crossing
situation. The crossing situation can be considered the ‘default’
risk-of-collision situation, except for when, as the Rules described, the
situation in which there is a risk of collision is considered to be a head-on
situation or an overtaking situation, as described in Rules 13 and 14.
This rule
applies only between power-driven vessels, and not vessels which, for whatever
reason, a power-driven vessel is directed to keep clear of or avoid impeding as
described in Rule 18.
This rule
also most emphatically does not apply in restricted visibility, the rules for
which are covered exclusively by Rule 19 and the other sound and light signal
rules towards the end of the Rules.
This rule
states that a vessel which has the other on her own
starboard side shall keep out of the way; this vessel is known as the
‘give-way vessel’. The other vessel is known as the ‘stand on
vessel’. It is equally useful to think of this rule in reverse; that is,
that the vessel that with the other on her port side should, as described in
Rule 17, hold her current course and speed, and expect avoiding action to be
taken by the other vessel.
This rule
requires the give-way vessel to avoid, if possible, crossing ahead of the other
vessel. Since she has the other on her starboard side, this means that more
often than not the give-way vessel will make an alteration of course to
starboard, although she is not forbidden by these rules to alter to port or
even cross ahead of the other vessel, should it be necessary and safe to do so.
A crossing
situation only exists if there is a risk of collision; it is not,
paradoxically, a crossing situation if one vessel is going to cross the path of
the other vessel so as for there to be no risk of collision.
Rule
16
Action by the give-way vessel
Every vessel which is directed to keep out of the way
of another vessel shall, so far as possible, take early and substantial action
to keep well clear.
Rule 15
requires a give-way vessel to keep out of the way, and in accordance with Rule 8,
she should do this in ample time. This rule is therefore slightly superfluous,
but it does make clear the necessity of taking early action. Rule 17 dictates
the rules for action to be taken by stand-on vessels when give-way vessels are
not taking sufficient avoiding action. That such action is required by this
rule to be early allows the stand-on vessel identify when such action should
have been taken by the give-way vessel, and therefore when she can safely take
avoiding action.
This rule is
not specifically meant to apply to vessels in a crossing situation, but it
applies to all instances where one vessel is required to keep out of the way
(keep clear) of another vessel. This is especially important with regards to
Rule 18, which delineates the responsibilities between vessels. This rule does
not however apply to vessels which are required not to impede the passage of
another vessel. It also does not apply in conditions of restricted visibility.
It does apply to all vessels, not specifically power-driven vessels.
Rule
17
Action by stand-on vessel
(a) (i) Where
one of two vessels is to keep out of the way the other shall keep her course
and speed.
Although this
rule is lumped together with the rules for crossing vessels, and indeed is highly
relevant in that case, this is a general rule, and is especially relevant not
only to Rule 15 but also Rule 18, which describes the responsibilities between
vessels.
This Rule
means that where another vessel is required by these Rules to take avoiding
action and keep clear, your vessel should hold her course and speed. This
allows the other vessel to take decisive action; she cannot make a decision and
follow it through safely if alterations of course are to occur.
(ii) The
latter vessel may, however, take action to avoid collision by her manoeuvre
alone, as soon as it becomes apparent to her the vessel required to keep out of
the way is not taking appropriate action in compliance with these Rules.
Give-way
vessels are required by Rule 16 and Rule 8 to take early and substantial action
to keep well clear. If such action is not taken early, then she may take action
to avoid collision herself without first giving any other form of indication or
warning, although she must make the appropriate sound signals as described by
Rule 34 if necessary for altering course or operating astern propulsion as
normal.
Although a
vessel, by this part of this Rule, may
take action to avoid collision as soon as she determines that the other vessel
is not going to take early action, she is not obliged to by this part of this
Rule.
As per Rule
34 part (d), a vessel may make a signal consisting of at least five short and
rapid blasts on the ship’s whistle, possibly accompanied by at least five
short and rapid flashes with the ship’s light signalling appliance,
before she takes action herself, which signals to the other vessel that she is
not taking sufficient avoiding action and/or doubt exists as to the intentions
of the avoiding vessel; she is not, however, obliged to do so.
Note that
vessels that are for whatever reason to be kept clear of because they are
unable to manoeuvre according to the Rules are still permitted to take avoiding
action by this Rule, even if they cannot manoeuvre for whatever reason.
(b) When,
from any cause, the vessel required to keep her course and speed finds herself so close that collision cannot be avoided by the
action of the give-way vessel alone, she shall take such action as will best
aid to avoid collision.
Part (a)(ii) allows stand-on vessels to take avoiding action, but
this part requires that they take
such action. This Rule also applies to vessels that cannot manoeuvre according
to the Rules; it does not stipulate that such action should necessarily consist
of a manoeuvre.
At the very
least, this action should consist of making the signal described in Rule 34
part (d) to alert the other vessel she is not taking sufficient action to avoid
collision. If she is, however, able to make a manoeuvre, this Rule requires
that she make such a manoeuvre. If a vessel cannot avoid a collision, then by
carrying out the instructions of this Rule, she has obeyed the Rules, and she
cannot be considered responsible for that collision, but this is only the case
if she has taken whatever action which had best
aided avoiding a collision; this means that any action she takes should be as
early and as substantial as possible. Rule 2 specifically requires that a
departure from the Rules may be necessary, and that even by following this
Rule, she cannot be exonerated if a collision occurs.
(c) A
power-driven vessel which takes action in a crossing situation in accordance
with subparagraph (a)(ii) of this Rule to avoid
collision with another power-driven vessel shall, if the circumstance of the
case admit, not alter course to port for a vessel on her own port side.
This rule
only applies in a crossing situation, which only occurs between power-driven
vessels. A vessel directed to keep out of the way of another in any other
circumstances may alter course to port for a vessel on her
own port side, if it is safe to do so.
This rule
does not forbid vessels to alter port if it is necessary and safe to do so; it
also does not forbid a vessel from making an alteration of course to port for a
vessel other than the crossing vessel. It does, however, forbid making such an
alteration of course if it is safe and possible to make an alteration of course
to starboard, or if it is reasonably possible to avoid a collision by an
alteration of speed.
(d) This
Rule does not relieve the give-way vessel of her obligation to keep out of the
way.
The knowledge
that if a give-way vessel does not keep out of the way the stand-on vessel will
does not permit the give-way vessel to leave it to the stand-on vessel; she is
still obliged to take early and substantial action to keep well clear.
Rule
18
Responsibilities between vessels
Except where Rules 9, 10 and 13 otherwise require:
This refers
to exceptions made in these rules that require special action to be taken either
by the stand-on or give-way vessel (as described by this Rule). These rules
mentioned are the rules for narrow channels and fairways, traffic separation
schemes, and overtaking situations. Rules 9 and 10 apply in any condition of
visibility, and Rule 13 applies only in conditions outside of restricted
visibility, but in restricted visibility, this Rule does not apply. This is
partly because the type of vessel can only exactly be determined by the shapes
and/or lights she is displaying, which in restricted visibility, by definition,
another observing vessel will not be able to identify.
(a) A
power-driven vessel underway shall keep out of the way of:
Note that she
does not have to be making way. A vessel stopped and making no way through the
water is required adjust her speed and make way in order to avoid any incoming
vessels as follows.
(i) a vessel not under command;
(ii) a vessel restricted in her ability to manoeuvre;
(iii) a vessel engaged in fishing;
(iv) a sailing vessel.
Vessels not
under command, or restricted in their ability to manoeuvre, or engaged in
fishing, may be types of power-driven vessels but because their ability to
manoeuvre is, by definition, hampered or absent, they aren’t required to
keep out of the way of other vessels as required by this rule, or indeed any
rule that requires something of power-driven vessels. An exception exists under
part (c) of this rule for fishing vessels.
Such vessels
may also be propelled, in normal circumstances, by sail, although in most
situations in modern shipping, this will not be the case. There is no conflict
caused by this under the Rules; such vessels are treated as such vessels first,
and power-driven or sailing vessels second.
(b) A
sailing vessel underway shall keep out of the way of:
(i) a vessel not under command;
(ii) a vessel restricted in her ability to manoeuvre;
(iii) a vessel engaged in fishing.
Note that
Rule 12 describes which of two sailing vessels shall keep out of the way of
another. Power-driven vessels are normally obliged to keep out of the way of
sailing vessels and not vice versa. In narrow channels and traffic separation schemes, sailing vessels are not required to keep
out of the way of other vessels, but are required not to impede their passage,
which is more fully described in Rules 9 and 10. Under Rule 13, if a sailing
vessel is overtaking any other type of vessel, then Rule 13 applies, and she is
directed to keep out of the way of the other vessel. She then becomes the give
way vessel, and since Rule 13 ‘trumps’ other Rules, any type of
other vessel then becomes the stand-on vessel and is therefore obliged to hold
her course and speed.
(c) A
vessel engaged in fishing when underway shall, so far as possible, keep out of
the way of:
(i) a vessel not under command;
(ii) a vessel restricted in her ability to manoeuvre.
The proviso
that vessels engaged in fishing shall keep out of the way of vessels not under
command or restricted in their ability to manoeuvre only if possible exists because
fishing vessels are defined as such because their manoeuvrability is
restricted, but not in such a way as prevents them from being able to manoeuvre
as required by the Rules.
As with
sailing vessels, Rules 9 and 10 require fishing vessels not to impede the
passage of vessels in narrow channels or traffic separation schemes, and this
is more fully described there. Other vessels are still obliged to keep clear of
vessels engaged in fishing where a risk of collision exists, and not vice
versa, but such risk of collision should not arise in accordance with those
Rules.
(d) (i) Any
vessel other than a vessel not under command or a vessel restricted in her
ability to manoeuvre shall, if the circumstances of the case admit, avoid
impeding the safe passage of a vessel constrained by her draught, exhibiting
the signals in Rule 28.
This does not
mean that they are directed to keep clear of or keep out of the way of such
vessels, but that due to their actions, a risk of collision should not develop
that requires them to take action to keep out of the way of such a vessel.
A vessel is
only to be considered constrained by her draught if she is displaying the
lights and/or shapes for a vessel constrained by her draught, as described in
Rule 28. She may elect not to display such lights and shapes.
Vessels not
under command and vessels restricted in their ability to manoeuvre are unable
to take action to avoid impeding the passage of a vessel constrained by her
draught and are thus not obliged to comply with this part of this Rule.
(ii) A
vessel constrained by her draught shall navigate with particular caution having
full regard to her special condition.
Other vessels
shall only be obliged to take action to avoid impeding the safe passage of a
vessel constrained by her draught when they are safely able to do so, as
described in part (i) of this part.
Vessels
constrained by their draught are able to alter course and speed, and therefore
manoeuvre as required by the Rules. They are, most commonly (but not
necessarily) confined to narrow channels. Such cannels are often not straight,
but incorporate bends that a vessel must alter course to navigate along.
Vessels constrained by their draught are also able to alter their speed to
avoid a collision.
Because this
is the case, all other Rules of part B apply to vessels constrained by their
draught as normal for power-driven vessels. Only power-driven vessels can be
considered constrained by their draught. The lights and shapes for a vessel
constrained by her draught may only be in addition to the lights and shapes
required for a power-driven vessels, so if a vessel does not and cannot display
such lights, she cannot also be a vessel constrained by her draught.
Because of
the allowances of this Rule, other vessels should take action to avoid forcing
a vessel constrained by her draught to alter her course or speed, but if a risk
of collision does develop, it can be assumed by the vessel constrained by her
draught that such action was impossible and therefore that she is completely
responsible for taking avoiding action herself as required by these Rules.
(e) A
seaplane on the water shall, in general, keep well clear of all vessels and
avoid impeding their navigation. In circumstances, however, where risk of
collision exists, she shall comply with the Rules of this part.
An aircraft
designed to manoeuvre on the water is a seaplane. Most such craft will be
power-driven vessels when on the water, since they will be propelled by
propellers, which is a form of machinery. Theoretically, a water-borne glider
or some other form of aircraft might be treated as a sailing vessel when on the
surface of the water.
An aircraft,
such as a balloon, that can land on the surface of the water but not manoeuvre
on it is not considered a seaplane, not a vessel, as it cannot, under Rule 3,
be considered capable of being used as a means of transportation over water.
This Rule therefore does not apply in such a case.
(f) (i) A
WIG craft, when taking off, landing and in flight near the surface, shall keep
well clear of all other vessels and avoid impeding their navigation;
A WIG craft
is directed to keep clear of other vessels and avoid impeding their navigation.
This means that in their main operational mode, they are also considered to be
power-driven vessels, and where risk of collision does exist, must be treated
as such, although this should not happen under most circumstances, partly
because of this rule.
(ii) A WIG
craft operating on the water surface shall comply with the Rules of this Part
as a power-driven vessel.
This is true
whether or not the WIG craft is in its main operational mode. WIG crafts are
much like aeroplanes, but are not seaplanes and when ‘flying’ are treated as power-driven vessels. This means that in addition
to other vessels treating a WIG craft as a power-driven vessel, the vessel
itself must behave in accordance with the rules for a power-driven vessel. This
means that she must, in addition to keeping well clear of all other vessels and
avoid impeding their navigation, obey the rules for traffic separation schemes
as described in Rule 10, narrow channels as described in Rule 9, and the Rules
for overtaking vessels in Rule 13, to name but a few, although all apply.
Section
III – Conduct of vessels in restricted visibility
Rule
19
Conduct of vessels in restricted visibility
(a) This
Rule applies to vessels not in sight of one another when navigating in or near
an area of restricted visibility.
This rule
applies to all vessels equally because it is impossible to exactly identify
vessels not in sight by their sound signals, as described in Rule 35, alone.
Similarly, there is no way to distinguish them by radar.
There are no
hard definitions of what constitutes restricted visibility, other than it should
be when visibility is restricted by fog, sand or whatever, as per Rule 3. No
ranges or distances are given, and it is up to the officer on watch to
determine whether conditions of restricted visibility exist. In general,
however, where a vessel cannot be seen that is nearby, or if conditions exist
where a vessel might not be detected visually if it were present, then
restricted visibility exists.
Certain
vessels have different nominal ranges for their sound-signalling appliances.
Where visibility is lower than this nominal range, conditions of restricted
visibility absolutely exist. This is described more fully in the notes for Rule
35, and the nominal ranges are described for sound signalling appliances in
Annex III part 1 (c).
Although
there might be deemed to exist conditions of restricted visibility, wherever in
such conditions two vessels can observe one another visually, the rules for
section II, that is, governing the conduct of vessels in sight of one another,
applies. This might happen, for example, when visibility is restricted to three
miles.
Vessels in
conditions of restricted visibility should make the appropriate sound signals
for vessels of their type as described in Rule 35.
It is assumed
that in conditions of restricted visibility, the primary means of detecting the
existence and location of other vessels will be by radar, although not all
vessels are required to be fitted with operational radar, and that such
information gained by the radar may be incomplete. Rule 6, part (b), and Rule 7
have much to say on this subject. The other method of detecting other vessels
in restricted visibility is by their sound signals. No other method counts;
vessels, by definition, cannot detect one another visually in conditions of
restricted visibility.
(b) Every
vessel shall proceed at a safe speed adapted to the prevailing circumstances
and conditions of restricted visibility. A power-driven vessel shall have her
engines ready for immediate manoeuvre.
The rules for
safe speed are described in Rule 6. These Rules still apply, as they apply in
all conditions of visibility. All vessels should at all times be able to alter
their speed, except where they cannot, for example, due engine failure. A
vessel may be not under command or restricted in its ability to manoeuvre, but
it is not treated specially under this Rule. Generally, the engine room team
prefer to know in advance when the telegraph might be used, so this rule is
usually interpreted to mean that the engine team, in conditions of restricted
visibility, shall know that it is likely the engine speed will be changed.
(c) Every
vessel shall have due regard to the prevailing circumstances and conditions of
restricted visibility when complying with the Rules of section I of this part.
Again, the
Rules of section I apply in all conditions of visibility. Therefore, they apply
in this section, too. This part is a reminder; all vessels are direction to
have due regard to the prevailing circumstances and conditions at all times
(buzz-word; situational awareness!)
(d) A
vessel which detects by radar alone the presence of another vessel shall
determine if a close-quarters situation is developing and/or risk of collision
exists. If so, she shall take avoiding action in ample time, provided that when
such action consists of an alteration of course, so far as possible the
following action shall be avoided:
This rule
means that any avoiding action may be taken, with the exception of such actions
as described below. Note that vessels are not directed to ‘keep
clear’ or ‘keep out of the way’, or ‘avoid impeding the
passage or safe passage of another vessel’ or any other specified type of
action; they are directed only to take ‘avoiding action’. This is
important; there are no stand-on or give-way vessels
in conditions of restricted visibility, and no rules of section II apply.
(i) an alteration of course to port for a vessel forward of the
beam, other than for a vessel being overtaken;
Rule 9
requires that a vessel in a narrow channel or fairway make a sound signal when
intending to overtake if the vessel to be overtaken has to take action to
permit safe passing, but such a sound signal may only be made when two vessels
can be observed visually from each other, and therefore a vessel may only
overtake another in restricted visibility in a narrow channel when the other
does not need to take any action to permit passage.
Note that if
a vessel is detected forward of the beam, but an alteration of course needs to
be made for a vessel not forward of the beam, then that is permitted, so long
as it does not lead to another close-quarters situation developing. This
especially complies with Rule 8 part (c).
Also note
that although an alteration of course to starboard is permitted, it is not
necessarily prudent to do so, especially when a vessel abeam is also off the
starboard bow.
(ii) an alteration of course towards a vessel abeam or abaft the
beam.
Although an
alteration of course should not be made towards a vessel abeam or abaft the
beam, this does not count when the other vessel is ‘finally past and
clear’. It can be said to be so when no single alteration of course is
likely to bring the two vessels close enough for risk of collision to exist.
Note that
part (i) of this part forbids an alteration of course for a vessel forward of the beam, but this part forbids any alteration of course towards a
vessel abeam or abaft the beam. Therefore, where a vessel exists, even if there
is no immediate risk of collision (except for when the other vessel is finally
past and clear) there can be no alteration of course towards it. A vessel that
has another on both her port and starboard quarter may not alter course. A
vessel which has another on her port bow may alter to port to avoid a vessel on
her starboard quarter, but she may not alter to starboard, and she may not
alter to port to avoid the vessel on her port bow.
(e) Except
where it has been determined that a risk of collision does not exist, every
vessel which hears apparently forward of her beam the fog signal of another
vessel, or which cannot avoid a close-quarters situation with another vessel
forward of her beam, shall reduce her speed to the minimum at which she can be
kept on her course. She shall if necessary take all her way off and in any
event navigate with extreme caution until danger of collision is over.
In accordance
with Rule 7 (a), if there is any doubt as to whether the sound signal has been
detected forward of the beam or abaft it, the risk of collision shall be deemed
to exist and appropriate action taken; in this case, reduce her speed to the
minimum that she can be kept on course and if necessary, taking all her way
off.
This part of
this rule states that where it has been determined that a risk of collision
does not exist, there is no need to reduce speed. This allows for one vessel to
overtake another. It also allows for the fact that if a vessel forward of the
beam is known to exist by radar, then it can be considered that there is no
risk of collision; however, caution should be exercised when assuming this is the
case as the size of the other vessel cannot be measured using the radar, and it
nominal range is not known; it could be that a vessel is approaching that is
not detected by radar. Rule 7 (c) says that assumptions shall not be made on
the basis of scanty information, especially not scanty radar information.
Assumptions of this nature generally should not be made, except where the
reliability of the radar information has been determined to be high.
PART C – LIGHTS AND SHAPES
Rule
20
Application
(a) Rules
in this part shall be complied with in all weathers.
In other
words, these Rules must be complied with whether in or outside of restricted
visibility. Even if visibility is effectively nil, lights and shapes must be
displayed. Because all vessels must remain visible at all times, according to
this Rule, if a vessel that has been observed by radar that is not visible, it
enables the officer on watch to judge ranges of visibility, which is extremely
important in determining whether or not conditions of restricted visibility
exist.
(b) The
Rules concerning lights shall be complied with from sunset to sunrise, and
during such times no other lights shall be exhibited, except such lights as
cannot be mistaken for the lights specified in these Rules or do not impair
their visibility or distinctive character, or interfere with the keeping of a
proper look-out.
This rule
should be compared with Rule 1, part (c), which mentions that lights, shapes
and whistle signals that are to be displayed in compliance with special rules
should be such that they cannot be confused with any lights, shapes and whistle
signals that are required to be displayed according to the Rules.
This rule
should also be compared to Rule 36, which expounds upon signals to attract attention,
and mentions that no such signals should be mistaken for any described
elsewhere in these Rules. This can include the ‘navigational
lights’ described in this part.
(c) The
lights prescribed by these Rules shall, if carried, also be exhibited from
sunrise to sunset in restricted visibility and may be exhibited in all other
circumstances when it is deemed necessary.
Note that
vessels are required to display such lights in restricted visibility; it is not
optional. It is optional at any other time, in other words, during the day in
conditions of good visibility. Many vessels have their lights on all the time;
this precludes the possibility of forgetting to activate them at night. In
restricted visibility, lights are usually visible before the rest of the vessel
is visible.
(d) The
Rules concerning shapes shall be complied with by day.
Note that
whilst lights are required to be visible from sunset to sunrise,
‘day’ is a less well defined measurement of time. It may mean from
morning twilight to evening twilight, in which case the time in which shapes
must be displayed slightly overlaps the time in which lights must be displayed,
which stands to reason since vessels should display their status at all times.
Shapes must
be displayed in restricted visibility, but it is not required that they are
displayed at night.
(e) The
lights and shapes specified in these Rules shall comply with the provisions of
annex I to these Regulations.
Annex I
covers the positioning and characteristics of lights and shapes. These
positions are described in the main bulk of the Rules, but exact requirements
are given in annex I. These regulations should be at least roughly familiar to
the mariner, as, especially with smaller vessels, the positioning of lights and
shapes may be somewhat surprising and can vary to quite a degree. Exact values
of chromaticity, brilliance and so forth aren’t measurable at sea, and
are provided for the shipbuilder’s concern. Additionally, the exact
spacing of lights and shapes is provided for the shipbuilder’s concern;
it is enough that the mariner is able to recognise the vessel type and aspect
of another vessel.
Rule
21
Definitions
All lights
are displayed show as to show one of four navigational light sector types.
These are; masthead lights, sidelights, stern lights, and all-round lights.
As this
illustration depicts, the sidelight sectors combine to form the masthead light
sector, abaft of which there exists the sternlight sector. All-round lights
form an unbroken arc of light projecting 360° around the vessel. This is
explained below more thoroughly, but it is worth remembering that the forward sectors extend to 22.5° abaft the beam. From this, the arcs of all other sectors can be
calculated, if need be, and easily described in those terms.
(a) Masthead
light means a white light placed over the fore-and-aft centreline of the vessel
showing an unbroken light over an arc of the horizon of 225° and so fixed
as to show the light from right ahead to 22.5° abaft the beam on either
side of the vessel.
Note that
this rule, as with all other rules concerning lights and shapes, may be
modified by Rule 1 (e) which governs vessels of special construction. This
particular rule is easy to remember as the arc extends 10% of its totality
abaft the beam on either side of the vessel (in other words, 225° ÷
10 = 22.5°.)
(b) Sidelights
means a green light on the starboard side and a red light on the port side each
showing an unbroken light over an arc of the horizon of 112.5° and so fixed
as to show the light from right ahead to 22.5° abaft the beam on its
respective side. In a vessel of less than 20m in length the sidelights may be
combined in one lantern carried on the fore-and-aft centreline of the vessel.
The latter
part of this rule may be modified, as per Rule 23 part (d) and Rule 25 part (b)
and part (c).
(c) Sternlight
means a white light placed nearly as practicable at the stern showing an
unbroken light over an arc of the horizon of 135°, and so fixed as to show
the light 67.5° from right after on each side of the vessel.
(d) Towing
light means a yellow light having the same characteristics as the sternlight
defined in paragraph (c) of this Rule.
The towing
light is shown as described in Rule 24 as required. Although this rule states
that it has the same characteristics as a sternlight, it is always shown in a
vertical line above the sternlight. The ‘same characteristics’ is
meant to mean that it must be of equivalent intensity, as required by Rule 22.
(e) All-round
light means a light showing an unbroken light over an arc of the horizon of
360°.
Note that as
all-round lights may be of any colour as required by the rules, no colour is
described here.
(f) Flashing
light means a light flashing at regular intervals at a frequency of 120 flashes
or more per minute.
Flashing
lights are used in these rules to indicate WIG craft and hovercraft; that is,
air-cushioned vessels operating in non-displacement mode. Hovercraft display an
all-round flashing yellow light, and WIG craft a high-intensity all-round
flashing red light, as described in Rule 23 (b) and (c).
Annex II part
3 describes the light signals to be displayed by purse seiners, a type of
fishing vessel. These are described as two yellow lights in a vertical line
that flash alternately every second and with equal light and occultation
duration. Although these are described as lights that flash, they are not
‘flashing’ as these Rules describe.
Rule
22
Visibility of lights
The lights prescribed in these Rules shall have an intensity as specified in section 8 of annex I to these
Regulations so as to be visible at the following minimum ranges:
Annex I
describes the luminosity in candelas for each type of light at each specified
range. There is a formula for this. As seafarers cannot identify luminosity, it
can be safely assumed that they aren’t required to remember the
requirements for different lights in those terms; instead, they ought only to
remember the nominal ranges of different lights in nautical miles. The luminosity
data is meant for shipbuilders.
Note that
this rule describes minimum ranges; the seafarer can expect to detect other
vessels by their lights at much longer ranges in optimal conditions.
(a) In
vessels of 50m or more in length:
- a masthead light, 6 miles;
- a sidelight, 3 miles;
- a sternlight, 3 miles;
- a towing light, 3 miles;
- a white, green, or yellow all-round light, 3 miles.
Vessels that
become visible at the nominal ranges described might not be identifiable until
they come closer. For example, if a target is identified by radar at a range of
3 miles, approaching, and a single white light suddenly becomes visible, then
it could be any number of vessels, at any aspect. Within 1 mile, however, all
lights belonging to any type of vessel become identifiable.
This
isn’t to say that useful information can’t be gleaned at greater
ranges. If the aforementioned single white light becomes visible at 3 miles, it
might be, for example, the single masthead light of a power-driven vessel of
30m in length; but if, at 2 miles, one or both of its sidelights are not
visible, then it cannot be the single masthead light of such a vessel; it must
be a different type of vessel or at a different aspect.
(b) In
vessels of 12m or more in length but less than 50m in length:
-
a masthead light, 5 miles; except that where the
length of the vessel is less than 20m, 3 miles;
-
a sidelight, 2 miles;
-
a sternlight, 2 miles;
-
a towing light, 2 miles;
-
a
white, red, green or yellow all-round light, 2 miles.
Note that
effectively two categories of vessel are described here, vessels between 20m
and 50m in length and vessels between 12m and 20m in length.
(c) In
vessels of less than 12m in length:
- a masthead light, 2 miles;
- a sidelight, 1 mile;
- a sternlight, 2 miles;
- a towing light, 2 miles;
- a white, red, green or yellow all-round light, 2 miles.
In conditions
outside of restricted visibility, a vessel of any type will be visible at a
range of 2 miles. Not all vessels display masthead lights, but if they do not, they
will be displaying some form of all-round light. If a vessel is detected by
radar, and it is not visible at a range of 2 miles, then it is certain that
conditions of restricted visibility exist.
(d) In
inconspicuous, partly submerged vessels or objects being towed:
- a white, all-round light, 3 miles.
This part of
this rule refers specifically to Rule 24 part (g). It does not refer to, for
example, submarines that have breached, and are therefore partly submerged
vessels, but are not being towed; in this example, such a vessel would be
lighted as a power-driven vessel of its length.
The
descriptions of the nominal ranges of the lights of vessels of different
lengths are a somewhat cumbersome way of expressing the nominal ranges of the
lights of those vessels. This table expresses the same information differently:
Vessel
> 50m Vessel
< 50m Vessel
< 20m Vessel
< 12m
Masthead
light 6
nm 5
nm 3
nm 2
nm
Sidelight 3
nm 2
nm 2
nm 1
nm
Sternlight 3
nm 2
nm 2
nm 2
nm
Towing Light 3
nm 2
nm 2
nm 2
nm
All-round
light 3 nm 2
nm 2
nm 2
nm
Rule
23
Power-driven vessels underway
(a) A
power-driven vessel underway shall exhibit:
(i) a masthead light forward;
(ii) a second masthead light abaft of and higher than the forward
one; except that a vessel of less than 50m in length shall not be obliged to
exhibit such a light but may do so;
(iii) sidelights;
(iv) a sternlight.
A
power-driven vessel is defined in Rule 3, definitions, and includes a sailing
vessel that is also using its engines, if fitted. A power-driven vessel is lit
in this way, but it may be lit in other ways in certain circumstances, such as
if it is not under command. Unless otherwise stated, if a vessel is lit in some
other way, it will not be lit as a power-driven vessel unless the particular
rule in question states that it shall be. See Rule 24, 26, 27, 28, 29 and 30.
A power-driven vessel, more than 50m in length, seen from astern. Vessels of less than 50m in
length may exhibit these lights, but are not obliged to.
A power-driven vessel, more than 50m in length, seen from right forward. Vessels of less than 50m in
length may exhibit these lights, but are not obliged to.
A power-driven vessel,
more than 50m in length, seen from the starboard side. Vessels of less
than 50m in length may exhibit these lights, but are not obliged to.
A power-driven vessel, more than 50m in length, seen from the port side. Vessels of less than 50m in
length may exhibit these lights, but are not obliged to.
A power-driven vessel, less than 50m in length, seen from astern.
A power-driven vessel, less than 50m in length, seen from right forward.
A power-driven vessel,
less than 50m in length, seen from the starboard side.
A power-driven vessel, less than 50m in length, seen from the port side.
(b) An
air-cushioned vessel when operating in the non-displacement mode shall, in
addition to the lights prescribed in paragraph (a) of this Rule, exhibit an
all-round flashing yellow light.
Note that no
location is given for this light, but it must be visible from every angle. It
is not required to be placed where can best be seen, nor as a masthead light,
forward masthead light, sternlight, or any other place; anywhere will do.
(c) A
WIG craft only when taking off, landing and in flight near the surface shall,
in addition to the lights prescribed in paragraph (a) of this Rule, exhibit a
high-intensity all-round flashing red light.
Again, as
with hovercraft, the high-intensity flashing red light does not need to be
placed in any specific location. WIG crafts especially, and to some extent
hovercraft, are vessels of special construction, and where the government of
any state shall have determined that such a vessel cannot comply fully with the
characteristics and locations of lights and shapes as required by the Rules (as
stated in Rule 1, part (e)) she shall instead have the locations and
characteristics of those lights and shapes as closely resembling those required
by these Rules as possible; therefore, WIG craft and hovercraft are likely to
appear unusually when view at night, but must otherwise comply with the rules
of this Rule in every way.
The flashing
red light described in this Rule is the only example of a high-intensity light
in the Rules. Nowhere in the Rules is it stated what constitutes a
‘high-intensity light’, but annex I of the Rules mentions, in
passing, that any light’s luminosity should be such as to prevent
‘undue glare’.
(d) (i) A
power-driven vessel of less than 12m in length may in lieu of the lights
prescribed in paragraph (a) of this Rule exhibit an all-round white light and
sidelights;
Such a vessel
will normally have the all-round white light displayed in the fore-and-aft
centreline of vessel, as mentioned in part (iii) of this part of this Rule.
This part does not require that such an all-round light should be placed on the
masthead, although since it is an all-round light it most likely will be. This
part of this Rule is an ‘either one or the other’ rule, and thus
precludes having a second mast-head light. The single, all-round white light
replaces both the masthead light and the sternlight, and may be in either or
neither location. It will still be possible to judge the aspect of such a
vessel from its sidelights.
Illustrations
for part (d) of this Rule are not provided as there are too many legal
permutations of carried lights.
(ii) a
power-driven vessel of less than 7m in length whose maximum speed does not
exceed 7 knots may in lieu of the lights prescribed in paragraph (a) of this
Rule also exhibit an all-round white light and shall, if practicable, also
exhibit sidelights;
This part is
effectively a restatement of part (i), except that power-driven vessels of less
than 7m in length are not required to display sidelights. The phrasing of this
Rule is such that vessels are required to display the sidelights if it is at
all feasible to do so.
Remember that
a single white light can mean many different things at any range, and may be
confused for a shore light.
(iii) the
masthead light or all-round white light on a power-driven vessel of less than
12m in length may be displaced from the fore-and-aft centreline of the vessel
if centreline fitting is not practicable, provided that the sidelights are
combined in one lantern which shall be carried on the fore-and-aft centreline
of the vessel or located as nearly as practicable in the same fore-and-aft line
as the masthead light or the all-round white light.
Note that the
single combined lantern may only be carried if the masthead light or lights or
all-round white light are not carried on the fore-and-aft centreline of the
vessel, and where this is the case, the sidelights must be combined into one
lantern, which may be carried either on the fore-and-aft centreline, or the
same fore-and-aft line as where the single white all-round light or masthead
light or lights are carried.
Rule
24
Towing and pushing
(a) A
power-driven vessel when towing shall exhibit:
(i) instead of the light prescribed in Rule 23(a)(i) or (a)(ii),
two masthead lights in a vertical line. When the length of the tow, measure
from the stern of the towing vessel to the after end of the tow, exceeds 200m,
three such lights in a vertical line;
(ii) sidelights;
(iii) a sternlight;
(iv) a towing light in a vertical line above the sternlight;
(v) where the length of the tow exceeds 200m, a diamond shape
where it can best be seen.
Vessels
engaged in towing other vessels or objects are still to be considered
power-driven vessels, and although they do not comply with Rule 23(a) part (i),
they do, as part (d) of this Rule states, comply with Rule 23(a)(ii), contrary to what this part of this Rule states.
This part of this Rule only applies to a vessel towing another vessel or
object behind it,
and does not apply to a vessel towing another alongside, or a vessel pushing
another ahead, unless those vessels are also towing other vessels behind. The
rules covering those types of vessels are also described in this part.
In restricted
visibility, vessels engaged in any type of towing or pushing ahead make the
same sound signal. This is described in Rule 35. However, only vessels or
objects towed behind make sound signals, and only if manned, and only the last
of such objects in a tow makes such a sound signal. This is described more
fully in the notes for that Rule.
When the
towing vessel is restricted in its ability to manoeuvre, Rule 27(c) applies,
which requires the vessel to display the characteristic lights and shapes of a
vessel restricted in its ability to manoeuvre. The towing vessel does not
always display such lights. It can be considered a vessel restricted in its
ability to manoeuvre under all other Rules, but although it displays the red,
white, and red all-round lights in a vertical line and/or the ball, diamond and
ball in a vertical line, it is not otherwise lit as a vessel restricted in its
ability to manoeuvre, but as a power-driven vessel that is also towing, and
happens to be restricted in its ability to manoeuvre.
(b) When
a pushing vessel and a vessel being pushed ahead are rigidly connected in a
composite unit they shall be regarded as a power-driven vessel and exhibit the
lights prescribed in Rule 23.
This only
applies to pushing vessels and the vessels to which they are connected, and not
any type of towing vessel. Part (f) of this Rule does not also apply.
(c) A
power-driven vessel when pushing ahead or towing alongside, except in the case
of a composite unit, shall exhibit:
(i) instead
of the light prescribed in Rule 23(a)(i) or (a)(ii), two masthead lights in a
vertical line;
(ii) sidelights;
(iii) a sternlight.
A vessel
engaged in pushing another vessel or vessels or objects or towing them
alongside is not regarded as a towing vessel, and is not lit as such, but may
be lit similarly. They do not display towing lights; only vessels towing
something behind display the towing light. The length of the tow or vessel
being pushed ahead does not affect how many lights or shapes the vessel shows,
and the vessel will never display three masthead lights or a diamond.
This rule
does not, however, preclude the possibility that vessel pushing another ahead
or towing alongside may also be towing another vessel
or object. If that is the case, they will show the towing light
as well, and may also show a third masthead light forward or a diamond if the
length of the objects being towed exceeds 200m.
(d) A
power-driven vessel to which paragraph (a) or (c) of this Rule applies shall
also comply with Rule 23 (a)(ii).
This is
probably the oddest rule described in the Rules. Parts (a) and (c) of this Rule
specifically state that power-driven vessels engaged in towing or pushing
should not obey Rule 23(a)(ii), and show a second masthead light; this Rule, on
the other hand, requires them to, but they are still not obliged if less than
50m in length.
(e) A
vessel or object being towed, other than those mentioned in paragraph (g) of
this Rule, shall exhibit:
(i) sidelights;
(ii) a sternlight;
(iii) when the length of the tow exceeds 200m, a diamond shape
where it can best be seen.
Note that
this rule does not apply to vessels being pushed ahead. It does not
specifically preclude vessels or objects towed alongside, either, although the
rules covering vessels (and not objects) towed alongside are described in part
(f) of this Rule, and are similar to this Rule in that instance except that no
mention of diamond shapes is made . Each vessel or object being towed displays
its own lights. Although both tug and tow display a diamond shape when the
length of the tow exceeds 200m, the tow does not display an additional light,
as the tug does on its forward masthead.
There is a
peculiar irregularity here. When a towing vessel is towing any number of
vessels or objects, the length of the tow is measured from the stern of the
towing vessel to the stern of the last vessel or object being towed. If this
distance exceeds 200m, she shows an additional masthead light forward, and/or a
diamond where it can best be seen. If there is only one vessel or object being
towed, and its length exceeds 200m, then it clearly must display a diamond from
where it can best be seen. However, where there are several smaller objects
that come to more than 200m, it is not clear as to whether they should, or
should not, display a diamond shape, and if so, on which vessel or object the
shape should be displayed, if not on all. If only one such diamond is to be
displayed, then it may be that it must be displayed from where can best be seen
on any of the vessels or objects in tow.
It may be
that if the length of a specific vessel or object being exceeds 200m, then that
object, regardless of whether there are other vessels or objects being towed,
displays the diamond shape. As this interpretation conveys the most
information, the author regards this as the most likely interpretation.
Therefore, a towing vessel that displays the diamond shape might be encountered
with vessels being towed that do not display the diamond, or that display more
than one.
It is not
immediately clear whether part (iii) of this Rule applies to vessels being
towed alongside or not. Part (f) of this Rule states that where several vessels
are being towed alongside, they shall be lit as a single vessel. If it is
interpreted that vessels being towed alongside are being towed and therefore
that this Rule does apply, then since part (f) only covers vessels, and details
only how they should be lit, not mentioning shapes, then each vessel towed
alongside should display a diamond shape if longer than 200m individually, if
the aforementioned interpretation is accepted. If not, however, only diamond
shape, if any, should be shown, from where can best be seen on any vessel, if
any vessel is greater than 200m in length. Because the vessels and/or objects
are towed alongside, their cumulative length of the vessels and objects is
irrelevant.
Part (h) of
this Rule allows for vessels or objects that cannot practicably be lit
according to this Rule to be lit as best they can be, or at least for the presence
of the vessel or object to be indicated.
(f) Provided
that any number of vessels being towed alongside or pushed in a group shall be
lighted as one vessel,
This states
that such vessels shall be lighted as one vessel, and that where this is the case,
the following Rules shall be followed. This rule applies not just to several vessels, but any singular vessel being pushed
ahead or towed alongside, and does not apply to any objects. It also does not,
as mentioned in the notes for part (e) of this Rule, govern the placement of
any types of shapes.
(i) a vessel being pushed ahead, not being part of a composite
unit, shall exhibit at the forward end, sidelights;
This part
clarifies that part (f) does not apply if part (b) does. The vessels being
pushed ahead displays sidelights, and only sidelights, and only at the forward
end, and can cover any number of vessels of any length. This rule does not
explicitly include objects; therefore, any type of object being pushed ahead
need not be lit at all.
(ii) a vessel being towed alongside shall exhibit a sternlight
and at the forward end, sidelights.
Note that
unless vessels or objects towed alongside are to be considered vessels or
objects being towed, then objects that are not inconspicuous or partly submerged
are not lit at all, but if they are, part (e) would apply, and they would be
lit separately, whereas vessels towed alongside, following this part, are lit
as one. If part (e) is deemed not to apply to such objects, then part (g) ought
not to apply, either, but if it is, it applies only inconspicuous or partly
submerged objects.
The
author’s view is that vessels or objects towed alongside are considered
vessels or objects being towed, and are lit as described in part (e), and also
display the shapes described in part (e). Without this interpretation, objects
being towed alongside or pushed ahead are unlit, which is clearly more
dangerous than the contrary, and henceforth the spirit of the Rules is complied
with to a greater extent. Under this interpretation, partly submerged and/or
inconspicuous vessels and objects being towed alongside also obey part (g) of
this Rule.
Another
peculiarity of this Rule is that vessels being towed alongside, whilst they
must be lighted as one vessel, may not be on the same side of the towing vessel
and if treated as one vessel, in any case, the fore-and-aft centreline of such
a combined vessel is likely to exist apart from the actual fore-and-aft
centreline of any of the composite vessels.
There are two
possible solutions to this problem. The first is that the Rules are to be
complied with to the letter, such that such a combined vessel is lit exactly as
the rules require. The starboardside most vessel displays its starboard
sidelight, the portside most vessel displays its port sidelight, and some way
is found of suspending a sternlight between the two vessels furthest out so
that the stern light can be displayed exactly upon a line which is laterally
equidistant from both sidelights. Such a sternlight might be suspended from a
cable, or if luck should so have it, may be displayed from a vessel which
straddles the theoretical combined centreline.
The other
possible solution is to simply display such lights as most closely follow the
Rules, treating the combined vessel as a vessel of ‘special
construction’. Such an arrangement may need to be approved by ‘the
government of any state’, as required by Rule 1 part (e).
(g) An
inconspicuous, partly submerged vessel or object, or combination of such vessels
or objects being towed, shall exhibit:
Part (e) of
this Rule specifically mentions that objects covered by part (g) of this Rule
are exempt from the need to comply with part (e). Part (h), as with part (e),
allows for vessels that cannot practicably be lit according to the requirements
of this part of this Rule to be lit as well as possible, or at least their
presence somehow indicated.
(i) if
it is less than 25m in breadth, one all-round white light at or near the
forward end and one at or near the after end except that dracones need not
exhibit a light at or near the forward end;
A dracone is
a bag that is used to transport bulk liquids, usually oil or its products,
through the water. The forward and after ends of the object being towed should
be along the centreline of the object, which should be in line with the
centreline of the towing vessel.
(ii) if it is 25m or more in breadth, two additional all-round
white lights at or near the extremities of its breadth;
The object
may be of any shape, so that the extremities of the object’s breadth
might be closer to the stern than the forward end; or, the greatest extremity
of its breadth might be closer to the forward end on the port side, and closer
to the stern on the starboard side. The greatest extremity of the breadth of
the vessel is a the greatest lateral distance from the
fore-and-aft centreline of the vessel. The fore-and-aft centreline of the
vessel should be in line with the fore-and-aft centreline of the towing vessel.
(iii) if it exceeds
100m in length, additional all-round white lights between the lights prescribed
in subparagraphs (i) and (ii) so that the distance between the lights shall not
exceed 100m;
Note that the
maximum distance between lights is
100m, and that these additional lights are placed between not only the lights
at either end, but between the lights at the extremities of its breadth, as
well.
This part of
this rule does not apply until the length of the vessel or object being towed
exceeds 100m. If the breadth exceeds 100m, then no additional lights need be
placed.
This rule is
a little vague as to where exactly the lights ought to be placed. There are
several possible interpretations of this Rule. Note that if an object is
greater than 100m in length, but less than 25m in length, no lights are to be
placed at the extremities of the vessel’s breadth, and therefore
additional lights will be placed on the fore-and-aft centreline of the vessel.
In this case, there is only one, straightforward interpretation of this Rule.
Where lights
are placed at the extremities of the vessel’s breadth, if the vessel is
greater than 100m in length, the vessels at the extremities of its breadth may
be less than 100m from the lights at either end of the vessel’s length.
In this case, although the distance between the lights is less than 100m,
additional lights still need to be placed, as the vessel is more than 100m in
length, and therefore part (iii) must be followed.
It can be
interpreted that the additional lights must be placed on the midpoints of each
line formed upon an imaginary quadrangle the corners of which consist of each
light at the forward, aft, and each extreme end of breadth of the object being
towed. The problem with this interpretation is that, for a very large object, there
would be an area in the centre that remains unlit; although, since each light
is within 100m of another light, it still complies with the Rule.
Another
interpretation is that lights are placed along the fore-and-aft centreline of
the vessel, and along an imaginary line between the extremities of the breadth
of the vessel. Under this interpretation, two all-round white lights might
need, for example, to be placed next to each other on an object at or just over
100m long and wide, and on a particularly large object, the port bow, starboard
bow, port quarter and starboard quarter would remain unlit, yet still, each
light would be within 100m of every other light.
A third
interpretation is that the exact placement of the additional lights disregards
the exact position of the forward and aft lights, and the lights at the extreme
breadth of the vessel, and that additional lights are placed in whatever
location is deemed most practical, so long as at least one additional light is
placed where the vessel is 100m long or longer, probably in the centre of the
vessel.
The third
interpretation seems the most likely, and by definition, the most practical,
and does indeed comply with the Rules, since it complies both with part (i) and
(ii) and ensures that no light is greater than 100m from any other light. It
does mean, however, that there might be a dazzling variety of configurations of
lights that the observant mariner must look out for.
(iv) a diamond
shape at or near the aftermost extremity of the last vessel or object being
towed and if the length of the tow exceeds 200m an additional diamond shape
where it can best be seen and located as far forward as is practicable.
It is clear
where the aftermost diamond shape ought to be placed, but there is still some
confusion as to whether the diamond shape ought to be placed forward and from
where it can best be seen on only the closest object to the towing vessel if
the entire length of the tow exceeds 200m, or only on an object that exceeds
200m in length, and possibly on several objects if more than one exceeds 200m
in length.
The author
tends to think that this Rule is to be interpreted to mean that any singular
object that is greater than 200m in length should display on it a diamond shape
forward from where it can best be seen. This conveys the most useful
information.
(h) Where
from any sufficient cause it is impracticable for a vessel or object being
towed to exhibit the lights or shapes prescribed in paragraph (e) or (g) of this
Rule, all possible measure shall be taken to light the vessel or object towed
or at least to indicate the presence of such vessel or object.
This rule
does not apply to vessels that normally are not engaged in towing other
vessels, and that are, for example, towing another vessel because of some
emergency on board that vessel. This Rule applies mainly to vessels that
normally are engaged in towing. It may be impracticable to light the vessel
being towed, but it is assumed that the towing vessel will have some means of
lighting or at least indicating the presence of the towed vessel on board as
part of her regular equipment.
(i) Where
from any sufficient cause it is impracticable for a vessel not normally engaged
in towing operations to display the lights prescribed in paragraph (a) or (c)
of this Rule, such vessel shall not be required to exhibit those lights when
engaged in towing another vessel in distress or otherwise in need of
assistance. All possible measures shall be take to
indicate the nature of the relationship between the towing vessel and the
vessel being towed as authorised by Rule 36, in particular by illuminating the
towline.
Rule 36 is
the Rule governing signals to attract attention, and states that any light or
sound signal so used so as to attract attention should not be mistakable for
any other light or sound signal in the Rules and also not mistakable for any
aid to navigation, or ‘embarrass’ any vessel, which in this context
means to interfere with another vessel’s watch, for example by blinding
another officer on watch and ruining his night vision.
This Rule
emphatically only applies to vessels that are not normally engaged in towing,
and are towing to assist another vessel, for example, on in distress.
Otherwise, part (h) applies. This part of this Rule authorises signals to
attract attention under Rule 36, whereas part (h) does not; both these Rules
apply equally to towing vessels and vessels being towed.
Towing
vessel, less than 50m in length, length of tow, less than 200m in length, seen
from the port side.
Towing vessel, less than 50m in length, length of tow, more than 200m in
length, seen from the port side.
Towing
vessels less than 50m in length may show a second masthead light abaft of and
higher than the two masthead lights forward, but a vessel 50m in length must
show it; tow, less than 200m in length, seen from the port side.
Towing
vessels less than 50m in length may show a second masthead light abaft of and higher
than the two masthead lights forward, but a vessel 50m in length must show it;
tow, more than 200m in length, seen from the port side.
Rule
25
Sailing vessels underway and vessels under oars
(a) A
sailing vessel underway shall exhibit:
(i) sidelights
(ii) a sternlight
There are
several vessels and objects that show sidelights and a sternlight, but no
masthead lights, including vessels or objects being towed as described in Rule
24. In addition, vessels not under command when making way display sidelights
and a sternlight, but no masthead lights, but also two all-round red lights in
a vertical line where they can best be seen; also, when making way, a pilot
vessel shows sidelights and a sternlight, but no masthead lights, but also
shows one white all-round light and below, one red all-round light in a
vertical line at the top of the masthead.
Nothing in
the Rules precludes a sailing vessel from also being a fishing vessel, a vessel
not under command, a vessel restricted in her ability to manoeuvre, a vessel
engaged in dredging or underwater operations, a pilot vessel, or a vessel at
anchor. A seaplane may even be considered a sailing vessel.
Sailing
vessels cannot display the lights that indicate that they are vessels
constrained by their draught, vessels engaged in towing, towing alongside or
pushing ahead unless they are also being propelled by machinery and thus
displaying the lights for a power-driven vessel instead of the lights for a
sailing vessel, for it is stated that such a vessel shall be considered a
power-driven vessel under Rule 3 part (c). Also, for the same reason, a sailing
vessel may not display the lights that would indicate that she is a vessel
engaged in mineclearance operations unless she is also at anchor.
The reason
for this is that the aforementioned lights must be shown in addition to the
lights for a power-driven vessel. They cannot be shown in addition to the
lights for a sailing vessel, and a sailing vessel may not show the lights for a
power-driven vessel, unless she is using her propelling machinery.
A sailing
vessel is not prohibited from towing, towing alongside or pushing, but this may
not be feasible and in any case she shows no lights or shapes to indicate this.
A sailing
vessel must indicate that she is engaged in fishing, not under command,
restricted in her ability to manoeuvre, engaged in dredging or underwater
operations, engaged in mine clearance operations, constrained by her draught,
engaged in pilotage duties, at anchor, or aground by hoisting the appropriate
shapes, if she is engaged in that activity.
These rules
are described under Rules 24, 26, 27, 29 and 30. Note that sailing vessels may
not be practically suited for many of these tasks, and may be unlike to find
themselves in any of these adverse statuses, but that they are not prohibited
from engaging in them merely because the rules do not require them to indicate
that they are so engaged.
Rule 27 part
(g) lifts many of the specific restrictions required under Rule 27 for vessels
under 12m in length.
(b) In
a sailing vessel of less than 20m in length the lights prescribed in paragraph
(a) of this Rule may be combined in one lantern carried at or near the top of
the mast where it can best be seen.
Note that
power-driven vessels of less than 12m in length, as mentioned in Rule 23(d)(iii), must combine their sidelights into one lantern that
is carried on the centreline or the same fore-and-aft line as the masthead
light or single all-round white is carried, if the masthead light or single
all-round white light is displaced from the centreline of the vessel. Such a
vessel can be distinguished from a sailing vessel by the aforementioned
masthead light or all-round white light.
(c) A
sailing vessel underway may, in addition to the lights prescribed in paragraph
(a) of this Rule, exhibit at or near the top of the mast, where they can best
been seen, two all-round lights in a vertical line, the upper being red and the
lower green, but these lights shall not be exhibited in conjunction with the
combined lantern permitted by paragraph (b) of this Rule.
These lights
confirm that vessel is, unambiguously, a sailing vessel.
(d) (i) A
sailing vessel of less than 7m in length shall, if practicable, exhibit the
lights prescribed in paragraph (a) or (b) of this Rule, but if she does not,
she shall have ready at hand an electric torch or light lantern showing a white
light which shall be exhibited in sufficient time to prevent collision.
Small sailing
vessels are not relieved from their requirement to show the lights required by
larger sailing vessels by this Rule; they must do so if it is practicable. In
the event of collision, if she did not use an electric torch to indicate her
presence and thus allow another vessel to recognise her and take avoiding
action to prevent a collision, she is considered fully responsible for the
collision occurring.
(ii) A
vessel under oars may exhibit the lights prescribed in this Rule for sailing
vessels, but if she does not, she shall have ready at hand an electric torch or
light lantern showing a white light which shall be exhibited in sufficient time
to prevent collision.
This rule is
similar to part (i) of this part, but it is important in that any vessel under
oar of any size may show lights as a sailing vessel but is not obliged to do
so, but if not, must indicate her presence in order to prevent a collision from
occurring if need be.
Most vessels
under oars will be small, but it is not impossible that a larger vessel might
exist; for example, a historical recreation of a trireme.
Vessels under
oars are not forbidden from engaging in the activities and being considered
under the statuses described in the notes for part (a) of this Rule, that is,
if Rules 24, 26, 27, 28, 29 and 30 apply. Vessels under oars are not required
to display the lights of a sailing vessel, but they are required to display any
lights and shapes required by Rules 26, 27, 29 and 30, even if they are not
required to display the lights for a sailing vessel.
(e) A
vessel proceeding under sail when also being propelled by machinery shall
exhibit forward where it can best be seen a conical shape, apex downwards.
If propelling
machinery is being used, the vessel is considered a power-driven vessel and
must display the lights for power-driven vessels under Rule 23. This can be
confirmed by Rule 3 part (c).
Two sailing vessels, side-by-side, seen from right ahead, both of which
are less than 20m in length. Sailing vessels of less than 7m in length should if
practicable display such lights, and vessels under oars may also choose to do
so.
Rule
26
Fishing vessels
(a) A
vessel engaged in fishing, whether underway or at anchor, shall exhibit only the
lights and shapes prescribed in this Rule.
This rule
applies whether the vessel is power-driven or treated as under sail. Vessels at
anchor are not underway, but more importantly, they are stopped and making no
way through the water. Note that a vessel engaged in fishing, by this Rule, is
required to display certain lights and shapes, even if it is not underway.
Rules 23 and 25, governing power-driven and sailing vessels, only apply when
underway.
A vessel
engaged in fishing is only considered as such when, according to Rule 3, it is
fishing with nets, lines, trawls, or any other fishing apparatus which
restricts manoeuvrability, but not trolling lines or other apparatus which does
not restrict manoeuvrability.
Also note
that whilst a fishing vessel has restricted manoeuvrability, it is NOT
considered a vessel restricted in its ability to manoeuvre. Rule 18 describes
the responsibilities between vessels, in which, under part (c), fishing vessels
are required to (to the best of their ability) keep clear of vessels not under
command or restricted in their ability to manoeuvre. Where they not able to
manoeuvre according to the Rules, this would be impossible; hence, fishing
vessels are considered able to manoeuvre. If they are not able to manoeuvre at
all, under this part of this Rule, they do not display any special lights or
shapes to indicate so. Thus, other vessels must treat them only as fishing
vessels (which usually means they must keep well clear.)
(b) A
vessel when engaged in trawling, by which is meant the dragging through the
water of a dredge net or other apparatus used as a fishing appliance, shall
exhibit:
(i) two
all-round lights in a vertical line, the upper being green and the lower white,
or a shape consisting of two cones with their apexes together in a vertical
line one above the other;
(ii) a
masthead light abaft of and high than the all-round green light; a vessel of
less than 50m in length shall not be obliged to exhibit such a light but may do
so;
(iii) when making way through the water, in addition to the lights
prescribed by this paragraph, sidelights and a sternlight.
Only trawlers
exhibit the green-over-white light, and only they display the second masthead
light; they never display the single white all-round light that indicates
outlying gear.
The white and
green all-round lights need be displayed anywhere on the vessel. Convention
places them forward, but they may be anywhere, and not necessarily where can
best be seen. Vessels larger than 50m must have a masthead abaft of and higher
than these vertical lights, which places them forward.
Part (d) of
this mentions annex II. Annex II only applies to vessels fishing within a
fleet.
Annex II
requires of trawlers greater than 20m in length using demersal or pelagic gear
to display two all-round white lights in a vertical line from where can best be
seen with a nominal range of 1 mile when shooting their nets; one all-round
white light over an all-round red light in a vertical line from where can best
be seen with a nominal range of 1 mile when hauling their nets, and two
all-round red lights in a vertical line from where can best be seen with a
nominal range of 1 mile when their nets have come fast upon an obstruction.
When engaged
in pair trawling at night, they should direct search lights at one another.
Vessels
smaller than 20m are not required to obey these rules as they relate to
trawlers, but may do so.
Purse seiners
are also types of trawler. A vessel fishing with purse seine gear may exhibit
two all-round yellow lights in a vertical line from where can best be seen with
a nominal range of one mile; these lights flash alternately every second and
with an equal light and occultation period. These lights may only be exhibited
when the vessel is hampered by its gear and do not count as flashing lights as
described under Rule 21 (f).
Trawlers,
when stopped and making no way through the water, do not display either
sidelights or a sternlight, but do once they start to make way. At anchor or
when not underway, they are stopped and making no way. At anchor, then, they
display no special lights or shapes to indicate that they are at anchor.
During the
day, trawlers and fishing vessels that are not trawling display the same
shapes, except when outlying gear exists.
(c) A
vessel engaged in fishing, other than trawling shall exhibit:
(i) two
all-round lights in a vertical line, the upper being red and the lower white,
or a shape consisting of two cones with apexes together in a vertical line one
above the other;
(ii) when
there is outlying gear extending more than 150m horizontally from the vessel,
an all-round white light or a cone apex upwards in the direction of the gear;
(iii) when making way through the water, in addition to the lights
prescribed in this paragraph, sidelights and a sternlight.
These rules
are similar to the rules described in part (b) for trawlers, except that such
vessels must not display a masthead light and so there is no indication of
their size.
They show a red
all-round light over a white all-round light in a vertical line, or two cones,
apexes together. As with trawlers, there is no location on the vessel that
these lights are required to be. As fishing vessels other than trawlers never
display a masthead light, there is no reason why these lights should be
forward, although convention places them there.
The
red-over-white lights should not be confused with the lights for a vessel
engaged in pilotage duty, which displays white-over-red lights. This is described
in Rule 29. The lights for a vessel engaged in fishing other than trawling can
be remembered by the phrase, ‘red over white, fisherman in sight’,
and those for a pilot boat, ‘white over red, pilot ahead’.
Annex II does
not apply to fishing vessels other than trawlers.
As with
trawlers, when stopped and making not way through the water, fishing vessels
other than trawlers display neither sidelights nor a sternlight.
The all-round
white light or a cone apex upwards is placed in the direction of outlying gear
extending more than 150m. This is to indicate that the vessel ought be passed on the side opposite to where the outlying
gear extends. This should not be mistaken for a masthead light.
(d) The
additional signals described in annex II to these Regulations apply to a vessel
engaged in fishing in close proximity to other vessels engaged in fishing.
The
intensity, and therefore, the nominal range, of the lights described in annex
II are not subject to the rules covered in Rule 22. Indeed, although they are
effectively all-round lights, they have a nominal range of at least 1 mile, but
otherwise must have a nominal range of less than that of any of the lights
required to be shown by a fishing vessel.
Because,
under Rule 22, the sidelights of a vessel of less than 12m have a nominal range
of 1 mile, so too, if a trawler is required to and chooses to show the lights
described in annex II, is the nominal range of the lights described in annex
II. Larger vessels show lights of greater ranges, which means that the annex II
lights may have a greater nominal range, but are not required to.
Trawling
lights described in annex II must always be lower than the navigational lights
described in this Rule.
(e) A
vessel when not engaged in fishing shall not exhibit the lights or shapes
prescribed in this Rule, but only those prescribed for a vessel of her length.
This vessel
is important, for a vessel must not be treated as a fishing vessel under the
Rules, especially under Rules 9, 10 and 18 unless she is displaying the lights
and shapes for a vessel engaged in fishing. Normally fishing vessels are
power-driven vessels, but they may be sailing vessels, so they must display not
only the lights and shapes for vessels of their length but also their type.
They may also, when not considered to be fishing vessels, vessels affected by
Rules 24, 26, 27, 28, 29 and 30. None of these rules apply when a vessel is
engaged in fishing, but in theory any of the circumstances that would
necessitate them to be complied with were they not engaged in fishing could
apply to vessels engaged in fishing so that the manoeuvrability of the vessel
is restricted.
A fishing
vessel other than a trawler stopped and making no way through the water, may or
may not be underway.
A fishing
vessel other than a trawler underway and making way through the water, seen
from the port side, with outlying gear extending more than 150m.
A trawler,
maybe more than 50m in length although a smaller vessel may still display the masthead
light which is displayed here, which is currently hauling its nets, stopped and
making no way through the water, may or may not be underway.
A trawler,
less than 50m in length, its nets come fast upon an obstruction, underway and
making way, viewed from the port side
Rule
27
Vessels not under command or restricted in their
ability to manoeuvre
(a) A
vessel not under command shall exhibit:
(i) two all-round lights in a vertical line where they can best
be seen;
(ii) two balls or similar shapes in a vertical line where they
can best be seen;
(iii) when making way through the water, in addition to the lights
prescribed in this paragraph, sidelights and a sternlight.
A vessel not under
command need not be a power-driven vessel under normal circumstances, but may
be a sailing vessel.
The lights
displayed by a vessel not under command are not in addition to any lights
required under any other Rule. If a vessel is not under command, she is
required to indicate that this is the case by exhibiting these lights and
shapes and no others. A vessel not under command is a vessel that is not able
to manoeuvre in compliance with the Rules, as defined by Rule 3 part (f). A
vessel cannot be considered ‘propelled by machinery’ or
‘under sail’ if she cannot steer or move forward, and the loss of
either of these functions means that such a vessel cannot be considered a
power-driven vessel or a sailing vessel as defined by Rule 3 part (b) and (c).
A vessel not
under command must display two all-round red lights in a vertical line, but if
she is not making way, she is not obliged to show either sidelights or a
sternlight. She never shows a masthead light or lights.
A vessel at
anchor does have the capacity to manoeuvre, if she weighs anchor, and so is
under command; however, a vessel at anchor may be not under command if she has
lost this capacity. In this case, she shows the lights and shapes for a vessel
not under command in addition to the lights and shapes for a vessel at anchor.
For a vessel
less than 100m in length, the lights that the Rules require to be displayed are
the same for a vessel aground as they are for a vessel not under command at
anchor. Larger vessels at anchor are required to display all deck and working lights, and smaller vessels may do so, if they are at
anchor; aground, they may not do so. Therefore, if a vessel is larger than 100m
in length, it is possible to tell a vessel aground and a vessel not under
command at anchor apart at night, and it may be possible if a smaller vessel
chooses to show all available deck and working lights.
During the
day, vessels not under command display two balls in a vertical line from where
can best be seen. A vessel at anchor displays one ball in the fore part. A
vessel aground displays, from where they can best be seen, three balls in a
vertical line. Unless ‘where they can best be seen’ is the fore
part of the vessel, the shapes displayed by vessels at anchor whilst not under
command and vessels aground are different and it is possible to tell them
apart.
Vessels not
under command cannot tow other vessels; therefore, a vessel may display either
the lights for a towing vessel, or a vessel not under command; not both.
A vessel not under command, and making no way through the water. May be made
fast to the shore; otherwise, underway.
A vessel not under command, underway and making way, seen from the
starboard side.
A vessel not under command at anchor. A vessel of less than 50m in length may display two
all-round lights, but a vessel of more than 50m in length, shall. A vessel of
less than 100m in length may show all available deck and working lights, but a
vessel of more than 100m in length shall. Viewed from the
starboard side.
A vessel of
less than 50m in length, may be aground, or may be at anchor, not under
command.
(b) A
vessel restricted in her ability to manoeuvre, except a vessel engaged in mine
clearance operations, shall exhibit:
A vessel
restricted in its ability to manoeuvre is so restricted because of the nature
of its work. Potentially, a vessel could have a steering or engine breakdown
during this time. In this situation, it becomes not under command; however,
this may not affect the vessel if it is able to continue working, or it may
affect the vessel in such a way as to prevent it from working; it may be able
to continue working, and be restricted because of that, whilst also being
restricted by engine or steering failure. Can such a vessel show both not under
command lights and restricted in its ability to manoeuvre lights? Should it
show one or the other?
If making
way, a vessel not under command should not show masthead lights. Therefore, to
do so would cause ambiguity; such a vessel might be mistaken for a vessel
engaged in dredging or underwater operations (see part (d) of this Rule.) For
this same reason, ambiguity could exist when stopped and not making way.
Although
there is no specific rule forbidding it, because of the potential confusion
that could arise from showing both lights at the same time, it should be
avoided. Vessels not under command and vessels restricted in their ability to
manoeuvre are treated, by other vessels, the same under the Rules, as explained
in Rule 18; therefore, it does not matter which is shown.
The
definition of a vessel restricted in its ability to manoeuvre is at Rule 3,
part (g), and includes specifically vessels laying, servicing, or picking up
navigation marks, submarine cables or pipelines, engaged in dredging, surveying,
or underwater operations, engaged in replenishment or transferring persons,
provisions or cargo while underway, engaged in the launch or recovery of
aircraft, engaged in mineclearance operations, and engaged in towing where the
tow and towing vessel are severely restricted in their ability to deviate from
their course, and may include any other type of vessel which, due to the nature
of her work, is unable to manoeuvre as required by the Rules.
Note that
fishing vessels, despite being defined as vessels with restricted
manoeuvrability, are not classed as vessels restricted in their ability to
manoeuvre.
This rule may
apply to either sailing or power-driven vessels, although it is usually
considered to apply to power-driven vessels. Note that vessels restricted in
their ability to manoeuvre need not be underway.
Normally,
when at anchor, part (iv) of this part applies, and
when stopped and making no way though the water, only part (i) and (ii) of this
part applies. However, a vessel engaged in dredging or underwater operations
does not obey this part, but part (d), and does not indicate that it is at
anchor. If no obstruction exists, it displays only the red, white, and red
lights at night and ball, diamond and ball shapes during the day, if not making
way, whether or not it is at anchor. Because of this, confusion exists; when
not making way, a vessel restricted in its ability to manoeuvre may or may not
be underway; there is no way to tell.
(i) three all-round lights in a vertical line where they can best
be seen. The highest and lowest of these lights shall be red and the middle
shall be white;
(ii) three shapes in a vertical line where they can best be seen.
The highest and lowest of these shapes shall be balls and the middle one a
diamond;
(iii) when making
way through the water, a masthead light or lights, sidelights and a sternlight,
in addition to the lights prescribed in subparagraph (i);
This rule
makes it quite clear that the authors of the IRPCS were thinking that only a
power-driven vessel would ever be considered restricted in its ability to
manoeuvre, as this rule states that when making way, it looks like a
power-driven vessel that is also displaying its RAM lights.
However,
nothing in the Rules prevents a sailing vessel from being restricted in its
ability to manoeuvre. The phrasing of this Rule seems to indicate, by saying
‘a masthead light or lights,’ that if the vessel restricted in its
ability to manoeuvre is greater than 50m in length, it should show a second
masthead light abaft of and higher than the forward one; however, this is not
strictly stated. It should be assumed that this is the intention, as there is
no other guidance as to the placement and number of masthead lights required.
Note that
when stopped, the vessel restricted in its ability to manoeuvre displays only
the red, white, and red all-round lights in a vertical line. Because this rule
gives clear instructions that sidelights, the sternlight, and masthead lights
are not to be shown unless the vessel is making way, it should be assumed that
the lights described in this Rule are instead of, as opposed to being in
addition to, the lights that are required to be shown for a vessel of its type.
(iv) when at anchor, in addition to the lights or shapes
prescribed in subparagraphs (i) and (ii), the light, lights or shape prescribed
in Rule 30.
Note that
this means in addition to whatever lights or shape must be shown for a vessel
at anchor, it also means only the red-white-red lights or ball-diamond-ball shapes
are shown. Despite any similarities between vessels aground and vessels at
anchor, vessels aground cannot also be restricted in their ability to manoeuvre
and cannot display these lights or shapes as well.
A vessel
restricted in its ability to manoeuvre, stopped and making no way through the
water, may or may not be underway.
A vessel
restricted in its ability to manoeuvre, a vessel of less than 50m in length may
display such lights but a vessel of more than 50m in length must do, underway
and making way, seen from the port side.
A vessel
restricted in her ability to manoeuvre, at anchor, seen from the port side,
less than 100m in length, vessel more than 50m must but a vessel less than 50m
in length may show these lights.
(c) A
power-driven vessel engaged in a towing operation such as severely restricts
the towing vessel and her tow in their ability to deviate from their course
shall, in addition to the lights or shapes prescribed in Rule 24(a), exhibit
the lights and shapes prescribed in subparagraphs (b)(i) and (ii) of this Rule.
This is a
special rule for vessels restricted in their ability to manoeuvre. Although a
vessel so restricted is required to show that she is, a towing vessel is also.
A vessel cannot tow if she is not under command, but she can if it is the
towing that is causing her to be restricted in her ability to manoeuvre.
Towing
vessels display towing lights in addition to the lights they display for
power-driven vessels, with exceptions described under Rule 24. Rule 24 does not
apply to sailing vessels, hence neither does this Rule. The lights in this Rule
are similarly in addition to the lights for a power-driven vessel, unlike part
(b), which are instead of the lights displayed by a power-driven vessel.
Note that not
all towing vessels are restricted in their ability to manoeuvre.
A towing
vessel, a vessel less than 50m in length may but a vessel more than 50m in
length must show these lights, towing an object more than 200m in length, restricted
in its ability to manoeuvre, seen from the port side.
(d) A
vessel engaged in dredging or underwater operations, when restricted in her
ability to manoeuvre, shall exhibit the lights and shapes prescribed in
subparagraphs (b)(i), (ii) and (iii) of this Rule and
shall in addition, when an obstruction exists, exhibit:
Note that (b)(iv) is not included, because of part (iii) of this part.
If a vessel is engaged in dredging or underwater operations without causing an
obstruction, parts (i) and (ii) of this part do not apply.
(i) two all-round red lights or two balls in a vertical line to
indicated the side on which the obstruction exists;
(ii) two all-round green lights or two diamonds in a vertical
line to indicate the side on which another vessel may pass;
Typically,
these lights will be exhibited from either end of the foreyard, but there is no
requirement for this under the Rules. When stopped and making no way through
the water, a vessel engaged in dredging or underwater operations shows no
aspect, and therefore it is impossible to judge whether or not an obstruction
exists on the vessel’s port or starboard side. These lights do, however,
indicated to the observer which side it is safe to pass on.
(iii) when at anchor, the lights or shapes prescribed in this
paragraph instead of the lights or shape prescribed in Rule 30.
It should be
noted that a vessel engaged in dredging or underwater operations displays no
indication that it is at anchor whatsoever. Since part (b)(iii)
of this Rule applies, however, when at anchor, it does not display sidelights
nor a sternlight, nor any masthead lights. Because of this,
it can be can be identified as underway when making way, but not identified as
being underway (or not) when it is stopped.
A vessel
engaged in dredging or underwater operations, stopped and making no way through
the water, may or may not be underway, an obstruction exists on the
viewer’s starboard side; it is safe to pass on the viewer’s port
side.
A vessel engaged
in dredging or underwater operations, underway and making way, a vessel more
than 50m in length must show these lights but a vessel of less than 50m in
length may show them, seen from right ahead, and obstruction exists on the
vessel’s starboard side, it is safe to pass on the vessel’s port
side.
(e) Whenever
the size of a vessel engaged in diving operations makes it impracticable to
exhibit all lights and shapes prescribed in paragraph (d) of this Rule, the
following shall be exhibited:
Part (g) of
this rule makes specific mention of diving vessels, stating that vessels of
less than 12m in length are not required to follow this Rule. Presumably, then,
a vessel must obey this Rule when she is 12m in length, and obey part (d) when
greater than.
(i) three all-round lights in a vertical line where they can
best be seen. The highest and lowest of these lights shall be red and the
middle light shall be white;
Again, a
vessel showing these lights is definitely restricted
in her ability to manoeuvre, but she cannot be judged to be underway or not,
and in this case, she may be making way.
A vessel of
this size is not required to show the lights and shapes required in part (d),
but this does not mean that she is not bound to follow part (d) entirely; part
(d)(iii) requires, when she is at anchor, that she does not show the lights for
vessels at anchor. Because she does not show the lights and shapes required by
part (d), she follows those for part (e) instead.
(ii) a rigid replica of the International Code flag
“A” not less than 1m in height. Measures shall be taken to ensure
its all-round visibility.
A flat,
rigid, 1m high copy of the alpha flag is a flat object and not visible from
every angle. It can therefore be assumed that several images of the alpha flag
should be shown; at least three, perhaps four. Alternatively, the replica could
rotate.
A copy of the International Code of Signals flag, “A”, or
Alpha.
(f) A
vessel engaged in mine clearance operations shall in addition to the lights prescribed
for a power-driven vessel in Rule 23 or to the lights or shape prescribed for a
vessel at anchor in Rule 30 as appropriate, exhibit three all-round green
lights or three balls. One of these lights or shapes shall be exhibited near
the foremast head and one at each end of the fore yard. These lights or shapes
indicate that it is dangerous for another vessel t approach within 1000m of the
mine clearance vessel.
Part (b)
specifically precludes vessels engaged in mineclearance operations. Only this rule
applies. Only power-driven vessels need show these lights or shapes, and only
they may be considered mineclearance vessels. Note that these vessels are
considered restricted in their ability to manoeuvre, although they do not show
the red, white and red all-round lights typical of other sorts of vessels
restricted in their ability to manoeuvre.
These lights
and shapes are in addition to the lights and shapes for a power-driven vessel,
unlike in part (b), in which the lights are shown instead of the lights for a
vessel of her type. A vessel engaged in mineclearance operations may be at
anchor, in which case these lights are again shown in addition to the lights
required by Rule 30.
A vessel
engaged in mineclearance operations less than 50m in length underway, may or
may not be making way, viewed from right forward.
A vessel
engaged in mineclearance operations, a vessel less than 50m may, but a vessel
greater than 50m in length must show these lights; less than 100m in length, at
anchor, viewed from the starboard side.
A vessel
engaged in mineclearance operations, a vessel less than 50m in length may, but
a vessel of greater than 50m in length must show these lights; underway, may or
may not be making way, as viewed from the starboard side.
(g) Vessels
of less than 12m in length, except those engaged in diving operations, shall
not be required to exhibit the lights and shapes prescribed in this Rule.
This means
that vessels smaller than 12m in length engaged in mineclearance operations are
not required to inform others of this fact! This may not, realistically, be an
issue.
This part of
this Rule does not say that smaller vessels may
display the lights and shapes required by this Rule; therefore, it may be assumed
that vessels smaller than 12m in length should not show them, even if not under
command or restricted in ability to manoeuvre. The exception to this is for
vessels engaged in diving activities, which, if less than 12m in length, follow
part (e) of this Rule and part (d), by extension.
Vessels of
this size follow the Rules for vessels of their type and size, that is, as
prescribed under Rules 23 or 25.
(h) The
signals prescribed in this Rule are not signals of vessels in distress and
requiring assistance. Such signals are contained in annex IV to these
Regulations.
Rule
28
Vessels constrained by their draught
A vessel constrained by her draught may, in addition
to the lights prescribed for power-driven vessels in Rule 23, exhibit where they
can best be seen three all-round red lights in a vertical line, or a cylinder.
Unlike many
other similar rules, vessels constrained by their draught are not required to
show these lights or this shape, but may do so. In doing so, they indicate that
their passage or safe passage is not to be impeded, as mentioned in Rule 18 part
(d).
Vessels the
passage or safe passage of which are not to be impeded are not unable to
manoeuvre as required by the Rules, being neither not under command nor
restricted in their ability to manoeuvre, and therefore, although their
navigational options are impeded by the fact that they are following a narrow
channel, are still considered able to obey the requirements of the Rules and
take action to avoid a collision; such action will more likely consist of an
alteration of speed than of course.
Other vessels
are required not to avoid impeding the passage or safe passage of a vessel
constrained by her draught, except for vessels not under command or restricted
in their ability to manoeuvre, but they are not directed to keep clear as they
would for, for example, a vessel not under command. This may amount to the same
thing in many circumstances, but when there are no other safe options and a
risk of collision exists with a vessel constrained by her draught, such a
vessel shall be treated as a normal power-driven vessel, in which case, she is
required to take avoiding action.
An example of
this is if she is following a dredged channel, surrounded by fishing vessels. A
power-driven vessel of a lesser draught is crossing her path from her starboard
side. The vessel of lesser draught cannot alter course, nor lessen her speed
whilst keeping clear of the fishing vessels, so she acts as a stand-on vessel,
making the vessel constrained by her draught the give-way vessel. The give-way
vessel must then reduce her speed to avoid a collision.
Only
power-driven vessels can be considered vessels constrained by their draught.
They must show the three red lights in a vertical line from where can best be
seen, or a cylinder, in addition to those required for a power-driven vessel.
This means that vessels towing, pushing or towing alongside can be considered
constrained by their draughts, as can vessels engaged in mineclearance
operations (see Rules 24 and 27 part (f)).
Towing
vessels can indicate that they are constrained by their draught and restricted
in their ability to manoeuvre. However, the fact that other vessels are
required to keep clear of a vessel restricted in its ability to manoeuvre makes
requiring them to avoid impeding her superfluous, so a towing vessel should not
show both lights, so as to minimise the chances of confusion.
A towing
vessel, less than 50m in length, constrained by her draught, length of tow more
than 200m, seen from the port side.
A
power-driven vessel constrained by her draught, a vessel of less than 50m in
length may, but a vessel of greater than 50m in length must show these lights,
as seen from the starboard side.
Rule
29
Pilot vessels
(a) A
vessel engaged on pilotage duty shall exhibit:
(i) at or near the masthead, two all-round lights in a vertical
line, the upper being white and the lower red;
The popular
saying, ‘white over red, pilot ahead’ can be used to remember this
configuration of lights. It should not be confused with the lights for a
fishing vessel other than a trawler, which displays one red over one white
light; that can be remembered as, ‘red over white, fisherman in sight.'
These lights
are displayed from the masthead, from where can best be seen. This is not
necessarily at the forward end of the vessel; pilot boats display no other
masthead lights when on duty, and since there is no
requirement to show any second masthead lights abaft of and higher than the
forward one, she may display these lights closer to the stern of the vessel.
Note that
these lights are shown from the masthead but are not masthead lights, but
all-round lights.
(ii) when underway, in addition, sidelights and a sternlight;
(iii) when at anchor, in addition to the lights prescribed in
subparagraph (i), the light, lights or shape prescribed in Rule 30 for vessels
at anchor.
These lights
are to be displayed instead of, not in addition to, the lights displayed for a
vessel of its type, and a vessel need not be power-driven to be considered a
pilot boat. Vessels at anchor that are on pilotage duty display the pilot
lights in addition to the anchoring light or lights; this is an exception to
the rule. The anchoring light will usually be one all-round white light where
can best be seen for few pilot boats will be as large as 50m in length. This
does not include vessels aground; they are not vessels at anchor, and may not
display pilot lights.
Note that
sidelights and a sternlight are exhibited when the pilot boat is underway, not
making way. Since at anchor she shows her anchoring light(s) and when aground
she cannot show pilot lights, a vessel displaying only a white all-round light
over a red all-round light can only be moored. Like power-driven vessels, there
is no way to distinguish a pilot boat making way from one stopped and making no
way through the water.
Because
vessels on pilotage duty do not comply with Rule 23 or 25, they cannot be
considered towing vessels, vessels constrained by their draught, or mineclearance
vessels, or any other type of vessel that shows its own lights and shapes
instead of those described in Rules 23 and 25 for power-driven and sailing
vessels.
(b) A
pilot vessel when not engaged on pilotage duty shall exhibit the lights or
shapes prescribed for a similar vessel of her length.
This Rule
makes it clear that sailing vessels (or vessels under oar lit as sailing
vessels) are not exempt from being considered pilot vessels.
A vessel engaged
on pilotage duty, seen from right forward, underway, may or may not be making
way.
A vessel
engaged on pilotage duty at anchor, seen from either right astern or right
forward, less than 50m in length.
Rule
30
Anchored vessels and vessels aground
Vessels at
anchor or aground are not considered underway, as define by Rule 3 part (i).
Rules 23 and 25 described the lights to be shown by power-driven and sailing
vessels respectively, but only when underway. Therefore, both obey this Rule
when aground or at anchor; vessels at anchor are not to be considered neither
power-driven nor sailing vessels for the purposes of the Rules.
The lights
and shapes to be displayed by vessels at anchor or aground are instead of, as
opposed to in addition to, the lights required elsewhere, except where it has
been explicitly stated.
Vessels at
anchor may be considered fishing vessels, but if they do, they do not obey this
Rule, but only show the lights and shapes dictated by Rule 26.
Vessels at
anchor are not explicitly allowed to also be considered vessels not under
command, but there is nothing in the Rules which disallows it, and vessels are
required to indicate that they are not under command or at anchor by their
lights and shapes, so it should be assumed that both lights and shapes can be
shown according to each rule. This is described in Rule 27 part (a).
Vessels
restricted in their ability to manoeuvre are explicitly required to show
appropriate lights and shapes, as described in Rule 27 part (b), in addition to
those they show at anchor.
A vessel
cannot tow at anchor. Vessels engaged in dredging or underwater operations at
anchor do not comply with this Rule, but instead comply with Rule 27 part (d)
and (e). Mine clearance vessels exhibit the lights and shapes described in Rule
27 part (f) in addition to those at anchor.
Vessels may
not be considered constrained by their draught at anchor. Pilot vessels at
anchor show pilot lights in addition to those they show at anchor, as described
in Rule 29.
There is no
Rule that specifically states other vessels must avoid or keep clear of vessels
at anchor, although obviously such vessels are unable to avoid or keep clear of
oncoming traffic. The reason for this is that such vessels are perfectly
manoeuvrable, unlike vessels not under command, for example. Rule 18, which
describes the responsibilities between vessels, requires power-driven vessels
and sailing vessels to keep out of the way or avoid impeding other types of
vessels. Because at anchor vessels are not underway and do not display the
lights and shapes for power-driven vessels or sailing vessels, it is possible
to interpret that such vessels are not considered
vessels of those types and therefore are under no obligation to keep clear of
or avoid impeding any other sort of vessel.
Without this
interpretation, they are still at anchor and under Rule 2, which requires an
officer of the watch to take precautions required by the ordinary practice of seamen,
and such a set of precautions should include keeping clear of vessels at
anchor.
(a) A
vessel at anchor shall exhibit where it can best be seen:
(i) in the fore part, an all-round white light or one ball;
(ii) at or near the stern and at a lower level than the light
prescribed in subparagraph (i), an all-round white light.
(b) A
vessel of less than 50m in length may exhibit and all-round white light where
it can best be seen instead of the lights prescribed in paragraph (a) of this
Rule.
(c) A
vessel at anchor may, and a vessel of 100m and more in length, shall also use
the available working or equivalent lights to illuminate her decks.
Vessels of
less than 50m in length are not obliged to display one all-round white light,
nor a vessels less than 100m obliged to refrain from
displaying her deck or working lights. A vessel showing only one all-round
white light at anchor must be less than 50m in length but she may also show her
working lights, and a vessel showing two anchor lights may be less than fifty
metres in length; if showing working lights, she may be of any length. A vessel
must show her deck lights if more than 100m and show two all-round white lights
if more than 50m in length.
Note that a
single white light can mean many things under the Rules; it may just as easily
be the stern light of any vessel not displaying any all-round lights. It could
also be the all-round light of a power-driven vessel less than 7m in length, or
the single masthead light of a power-driven vessel viewed from outside the
nominal range of her sidelights. A single white light could also belong to a
vessel aground of less than 12m, which is not obliged to indicate that is
aground as opposed to at anchor; this is described in part (f) of this Rule.
Caution
should be taken against confusing these requirements with those in Rule 35,
which governs sound signals in restricted visibility. Vessels more than 100m in
length must ring a bell in the fore part and then ring a gong in the after
part. This should be, if anything, equated with the requirement of vessels to
display their deck and working lights at anchor if the vessel is more than 100m
in length, as opposed to the requirement that they show two all-round lights if
greater than 50m in length.
Remember that
these Rules apply in all weathers, including restricted visibility; during the
day, the lights should be displayed in restricted visibility as it makes the
vessel visible at a greater range.
(d) A
vessel aground shall exhibit the lights prescribed in paragraph (a) or (b) of
this Rule and in addition, where they can best be seen:
(i) two all-round red lights in a vertical line;
(ii) three balls in a vertical line.
As has been
mentioned in the notes for vessels not under command in Rule 27 part (a),
vessels aground, at night, show the same lights as vessels not under command at
anchor. The exception to this is that vessels aground never show their deck or
working lights. During the day, vessels not under command show only two balls
from where can best be seen, in addition to the one ball in the fore part for a
vessel at anchor, but vessels aground show three balls from where can best be
seen, in addition to one ball in the fore part.
Vessels
aground of less than 50m in length may show only one all-round light instead of
two, one forward and one aft, just as vessel at anchor may.
Remember that
in restricted visibility, a gong is sounded in the after part of a vessel
aground if the vessel is more than 100m in length. (This is mentioned in Rule
35.) Remember this because vessels aground do not show deck or working
lights, even if they are over 100m in length, as anchored vessels do; but they do
sound a gong in the after part of the vessel if greater than 100m in length.
(e) A
vessel of less than 7m in length, when at anchor, not in or near a narrow
channel, fairway or anchorage, or where other vessels normally navigate, shall
not be required to exhibit the lights or shape prescribed in paragraphs (a) and
(b) of this Rule.
Vessels
should avoid anchoring in a narrow channel or fairway anyway. This exemption
from the need to comply with the Rules regarding anchoring only applies in
places where other vessels normally do not navigate; it is not a general
exemption. Also, this exemption does not apply to vessels aground; vessels
aground of less than 12m in length are so exempted from complying with part (d)
in part (f) of this Rule.
(f) A
vessel of less than 12m in length, when aground, shall not be required to
exhibit the lights or shapes prescribed in subparagraphs (d)(i)
and (ii) of this Rule.
Note that
this exemption does not exempt such vessels from the need to display the same
lights as a vessel at anchor when she is aground and less than 12m in length; such
vessels must display at least one all-round white light, or two if they so
choose, but even though they do not display two all-round red lights in a
vertical line or three balls, they may not show any deck or working
lights, as a vessel at anchor may.
Also note
that part (e) of this Rule, which exempts vessels of less than 7m in length
from the need to comply with the Rules regarding anchoring under certain
circumstances, does not exempt vessels of less than 7m from the need to comply
with thus Rule, which does not relate at all to anchoring, but to vessels
aground. Such vessels must show at least one white all-round light if aground.
A vessel aground, more than 50m in length, seen from the port side.
A vessel at
anchor, less than 50m in length, showing deck and working lights, this one seen
from the starboard side.
Rule
31
Seaplanes
and WIG craft
Where it is impracticable for a seaplane or a WIG
craft to exhibit lights and shapes of the characteristics or in the positions prescribed
in the Rules of this Part she shall exhibit lights and shapes as closely
similar in characteristics and position as is possible.
This Rule is
in some regards similar to Rule 1, part (e), except
that this Rule specifically governs the aforementioned WIG craft and seaplanes.
Chiefly, no government intervention or approval is required, although doubtless
regulations exist governing the sound design of aircraft and/or WIG craft.
PART D – SOUND AND LIGHT SIGNALS
Rule
32
Definitions
(a) The
word whistle means any sound
signalling appliance capable of producing the prescribed blasts and which
complies with the specifications in annex III to these Regulations.
Annex III
describes the qualities required by all sound signalling appliances on board a vessel.
Much of this is technical information, and the gross physical quantities of the
appliances involved, and will be of more concerned to the shipbuilder than the
mariner, as seamen have no means of measuring audibility.
Of note, the
audibility of sound signalling appliances is described. Vessels of 200m or more
must be audible for 2 miles; 75m or more, 1.5 miles; 20m or more, 1 mile, and
vessels smaller than 20m in length must be audible for 0.5 miles.
These nominal
ranges are important, because it greatly informs what should be the ‘safe
speed’ of a vessel, in reference to Rule 6. In addition, if it is clearly
visible that there are no vessels within the nominal range of the
sound-signalling appliances, there logically need be no legal obligation to make
a sound signal, and to make sound signals ‘just in case’ indicates
poor situational awareness.
(b) The
term short blast means a blast of
about one second’s duration.
(c) The term prolonged blast means a blast of from four to six second’s duration.
Rule
33
Equipment for sound signals
This Rule
dictates the requirements as to which types of sound signalling appliances are
required on vessels of certain length. Note that there is no differentiation
between power-driven vessels or sailing vessels. This Rule may be compared to
Rules 21 and 22, which describe the different types of lights and their
visibility and nominal ranges. Annex III contains the gross physical qualities
required of these appliances.
(a) A
vessel of 12m or more in length shall be provided with a whistle, a vessel of
20m or more in length shall be provided with a bell in addition to a whistle,
and a vessel of 100m or more in length shall, in addition, be provided with a
gong, the tone and sound of which cannot be confused with that of the bell. The
whistle, bell and gong shall comply with the specification in annex III to
these regulations. The bell or gong or both may be replaced by other equipment
having the same respective sound characteristics, provided that manual sounding
of the required signals shall always be possible.
(b) A
vessel of less than 12m in length shall not be obliged to carry the sound
signalling appliances prescribed in paragraph (a) of this Rule but if she does
not, she shall be provided with some other means of making an efficient sound
signal.
Rule
34
Manoeuvring and warning signals
Parts (a),
(c) and (d) only apply to vessels in sight of one another. Part (b) covers
lights signals, which are only sounded in addition to sound signals, and
therefore only when vessels are in sight of one another. Part (f) regards the
use of whistles if more than one whistle is fitted. Only part (e) of this Rule
applies both inside and outside of restricted visibility. Therefore, it is
prudent to think of Rule 34 as describing sound signals that apply when two
vessels are in sight of one another, and think of part (e) of this Rule as a
small exception.
(a) When
vessels are in sight of one another, a power-driven vessel underway, when manoeuvring
as authorised or required by these Rules, shall indicate that a manoeuvre by
the following signals on her whistle:
- one short blast to mean “I am altering my course to
starboard”;
- two short blasts to mean “I am altering my course to
port”;
- three short blasts to mean “I am operating astern
propulsion”.
Readers
familiar with the International Code of Signals will know that the flags,
“E”, “I” and “S”, or “ECHO”,
“INDIA” and “SIERRA”, mean, “I am altering my
course to starboard,” “I am altering my course to port,” and
“I am operating astern propulsion,” respectively. The Morse Code
for these signals is
▪ , ▪▪ and
▪▪▪ respectively. Therefore, this particular part of
this Rule is very easy to remember indeed.
It is very
important to remember to make these sound signals when making any alteration of
course outside of restricted visibility, and to remember not to
make these sound signals when in conditions of restricted visibility.
However, when it is clear that there are no vessels within the nominal range of
your vessel’s sound signalling appliances, there is no legal obligation
to make such sound signals.
Rule 8 parts
(a), (b) and (c) make it clear that alterations of
course made to avoid a collision should be sufficient that they can be easily
observed from another vessel. This part of this Rule states that manoeuvres
authorised or required by these Rules should be accompanied by an appropriate
sound signal described here. Strictly speaking, these Rules do not authorise
alterations of course (or the use of astern propulsion) for navigational
purposes, when no risk of collision or possibility of impeding another
vessel’s passage is involved. In addition, these manoeuvres are not
required to be bold, ‘in ample time’ or visible to another vessel
observing visually or by radar. However, it is in the best interest of the
navigator to inform other vessels of when ones vessel is to soon make a bold
alteration of course or operate astern propulsion, especially since when other
vessels are within the nominal range of ones ship’s whistle, a
‘close-quarters situation’ may be deemed to exist. Therefore, sound
signals should be made regardless of whether or not they are authorised by the
Rules.
Note that
three short blasts on the ship’s whistle is for use when a vessel is
about to operate astern propulsion, not simply when moving astern, or slowing
down; and indeed when operating astern propulsion, this sound signal should be
made, even when moving ahead.
There is some
debate as to whether tugs assisting vessels under pilotage leaving or entering
their berth under the direction of the pilot need make these sound signals. The
consensus is, generally, that they need not make these sound signals, although
some do. Strict interpretation of the Rules would suggest that they do, in
which case they should comply with Rule 24, which governs towing and pushing
vessels and vessels being towed or pushed ahead. There are many complications
to this, however, because several tugs may be in use, from several angles, some
pushing, some towing, some towing backwards, and so
forth. Special Rules made by appropriate authorities for harbours, as described
in Rule 1 part (b), trump the IRPCS, although they should resemble it; this may
include a suspension of these Rules (and Rule 24) for tugs assisting in the
pilotage of a vessel to or from a berth.
It is
essential to not that this Rule applies only to power-driven vessels. It
does not apply to sailing vessels.
Vessels not underway do not necessarily count as either
power-driven vessels nor sailing vessels (although this may not be
interpreted as being the case universally) but vessels not underway generally
do not manoeuvre.
(b) Any
vessel may supplement the whistle signals prescribed in paragraph (a) of this
Rule by light signals, repeated as appropriate, whilst the manoeuvre is being
carried out:
These signals
should only ever be made in addition to the sound signals, not instead
of. Part (iii) of this part states that the nominal range of this light shall
be 5 miles, which exceeds the maximum nominal range of the sound-signalling
appliances. No vessel is required to make these signals, but it is safer to do
so in order to inform other vessels of your movements.
Remember that
if another vessel is within a range below the nominal range of the
vessel’s sound signals, a vessel is legally required to make the sound
signals; above that, she is not, so she is not bound to make sound signals that
are required to be made before making lights signals, but she must make the
sound signals before she makes the light signals, even if nobody is within
range of the sound signals to hear them. Remember that often (more likely,
usually) the actual range of lights and sound signals exceeds the nominal
range, and more signals made means less of a risk of collision, as all parties
are more informed.
(i) these light signals shall have the following significance:
- one flash to mean “I am altering my course to
starboard”;
- two flashes to mean “I am altering my course to
port”;
- three flashes to mean “I am operating astern
propulsion”;
The notes for
part (a) of this Rule described how best to remember these; the signals, in the
Morse Code, are the same as for the sound signals.
(ii) the duration of each flash shall be about one second, the
interval between flashes shall be about one second, and the interval between
successive signals shall not be less than ten seconds;
This part may
be compared with Rule 32 which describes the length of short blasts on the
ship’s whistle, among other things.
(iii) the light
used for this signal shall, if fitted, be an all-round white light, visible at
a minimum range of 5 miles, and shall comply with the provisions of annex I to
these Regulations.
Note that the
signalling light described here is not mention in Rule 22, which describes the
visibility of lights; it is not a ‘navigational light’, nor a
searchlight, which is directional, and the range of 5 miles is the same for all
vessels. If this seems excessive for, for example, small yachts and rowing
boats, it should be recalled that it is not required of any vessel to make the
light signals described in part (b) of this part, and hence not required of
vessels to be equipped with such a light.
(c) When
in sight of one another in a narrow channel or fairway:
This Rule
specifically applies with Rule 9 part (e), which covers the conduct of vessels
in a narrow channel or fairway, specifically when one vessel, intending to
overtake another, requires the other vessel to move out of the way to permit
safe passage. This Rule, and Rule 9 part (e), do not apply when overtaking in
general, or when overtaking in a narrow channel when the other vessel need take
no action to permit safe passing.
(i) a vessel intending to overtake another shall in compliance with
Rule 9 (e) (i) indicate her
intention by the following signals on her whistle:
- two prolonged blasts followed by one short blast to mean
“I intend to overtake you on your starboard side”;
- two prolonged blasts followed by two short blasts to mean
“I intend to overtake you on your port side”.
This part of
this part of this Rule can be remember as the signal “MIKE” in the
Morse Code, that is, two prolonged blasts, ▬ ▬,
followed by the signal “ECHO” in the Morse Code, that is, one short
blast, ▪, for when a vessel is to be overtaken on the starboard side
(which can be remembered, as is the case in part (a) of this Rule, by the
equivalent flag,) or followed by the signal “INDIA” in the Morse
Code, that is, two short blasts, ▪▪, for when a vessel is to be
overtaken on the port side (which can be remembered, as is the case in part (a)
of this Rule, by the equivalent flag.)
(ii) the vessel about to be overtaken when acting in accordance
with Rule 9 (e) (i) shall indicate her agreement by the following signal on her
whistle:
- one prolonged, one short, one prolonged and one short blast,
in that order.
This part of
this part of this Rule can be remember as the signal “CHARLIE” in
the Morse Code, that is, one prolonged, one short, one prolonged and one short
blast, ▬▪▬▪. In the International Code of Signals, the
flag “C” for “CHARLIE” means, “Yes”, or,
the significance of the previous signal should be read in the affirmative. This
Rule is therefore easy to remember; the overtaking vessel signals, ‘may I
pass on the left?’ or ‘may I pass on the right?’ and then the
vessel replies, ‘yes,’ if he intends to take action to permit safe
passage.
There is no,
‘no,’ response in this part of this Rule. A vessel not intending to
take action is under no obligation to make any sound signal in response, in
which case, the vessel intending to overtake should not attempt to do so;
however, vessels may choose to respond by making the sound (and possibly the
accompanying light) signal described below in part (d) of this Rule, which
means, ‘I fail to understand your intentions,’ or, ‘I doubt
whether you are taking sufficient action to avoid collision.’ This is
specifically mentioned in Rule 9 (e) (i).
It does not
specifically state that vessels are allowed to make light signals instead of,
or to accompany these sound signals. Therefore, vessels are forbidden from
doing so. Since the overtaking vessel is behind the other, the vessel to be
overtaken is less likely to notice a light signal, anyway.
It is stated
in Rule 9 that sailing vessels are forbidden from impeding the passage of a
vessel that can safely navigate only within a narrow channel, and in general,
power-driven vessels are to keep clear from sailing vessels. However, sailing
vessels may overtake one another, and power-driven vessels, and follow the
Rules for overtaking vessels in Rules 9, 13, and 34. A sailing vessel may make
the signals described in this Rule, in order to ‘ask’ another
vessel to move out of her path. This is specifically allowed under Rule 13.
(d) When
vessels in sight of one another are approaching each other and from any cause
either vessel fails to understand the intentions or actions of the other, or is
in doubt whether sufficient action is being taken by the other to avoid
collision, the vessel in doubt shall immediately indicate such doubt by giving
at least five short and rapid blasts on the whistle. Such signal may be
supplement by a light signal of at least five short and rapid flashes.
This signal is
mentioned in Rule 9(e)(ii), but it may be used in any circumstance when deemed
necessary, especially when your vessel is a stand-on vessel and the other
directed to give way, but is not doing so.
The light
signal must be made in addition to the sound signal, not instead of. This
signal may not be used in restricted visibility. Note that light signals
made during the day are very unlikely to be noticed.
A vessel may
make a minimum of five short and rapid blasts on the ship’s whistle, but
she may make any number, so long as they are short and rapid. The minimum, that
is, five short and rapid blasts, can be remembered as “5” in the
Morse Code, that is, five short blasts, ▪▪▪▪▪.
(e)
A vessel near a bend or an area of a channel or fairway where other vessels may
be obscured by an intervening obstruction shall sound one prolonged blast. Such
signal shall be answered within hearing around the bend or behind the
intervening obstruction.
This part of
this Rule does not apply when vessels
are in sight of one another (what would be the point otherwise?) This is an
exception; the rest of this Rule applies to vessels in sight of one another. It
also, then, applies in conditions of restricted visibility, whereas the rest of
the parts of this Rule do not. It does not,
however, apply solely in restricted
visibility.
Because this
Rule applies only when another vessel might be obscured by some object or
other, no light signals may accompany these sound signals.
Both vessels,
whether calling or reply, make the same sound signal; this sound signal can be
remembered as “TANGO” in the Morse Code,
that is, one prolonged blast on the ship’s whistle, ▬.
Because any
and all vessels approaching a bend or intersection of a channel make this
signal, it can be assumed that the vessel that makes the signal first will
‘get there’ first, or in other words, is nearer. Common sense
therefore dictates that they should have ‘right of way’, allowing
the other vessel to slow down and navigate with caution knowing that a
close-quarters situation in a narrow channel may be approaching. The
appropriate course of action will vary with the situation and is not covered by
the Rules specifically, although knowing, and taking, the correct course of
action is considered part of the ‘ordinary practice of seamen’ and
is therefore required under Rule 2.
(f) If
whistles are fitted on a vessel at a distance apart of more than 100m, one
whistle only shall be used for giving manoeuvring and warning signals.
‘Manoeuvring
and warning signals’ means only the signals described in this part. It
does not say which of the two whistles shall be used.
Rule
35
Sound signals in restricted visibility
In or near an area of restricted visibility, whether
by day or night, the signals prescribed in this Rule shall be used as follows:
Note that
automatic sound signalling should commence before entry into a fog bank (or
other similar area of restricted visibility). A vessel inside an area of
restricted visibility will be unable to view a vessel outside it, so that it is
important for a vessel not in an area of restricted visibility but near it to
make sound signals so that a vessel within the area can detect the other by
sound.
(a) A
power-driven vessel making way through the water shall sound at intervals of
not more than 2 minutes one prolonged blast.
Note that a
power-driven vessel when making way can make sound signals more frequently than
once every two minutes. Consider the vessel’s speed when determining the
amount of time between sound signals; if a vessel is travelling at 15 knots,
she will travel half a mile between prolonged blasts if signalling only once
every two minutes. A vessel of less than 75m in length is required to have a
whistle with an audible range of only one mile; thus, if two such vessels were
approaching at that speed at a reciprocal course, they would have no time in
which to detect each other and thus avoid collision if conditions were such
that they are only able to detect each other by hearing one another’s
sound signal. Of course, in this example, 15 knots cannot be considered a
‘safe speed’ but it is always safer to reduce the amount of time
between prolonged blasts on the ship’s whistle.
In principle,
a vessel could simply produce one prolonged blast after the other as their
sound signal in restricted visibility. This could cause confusion with a
power-driven vessel stopped and making no way through the water, but not with
any other type of vessel, and also, not with a vessel in distress (a vessel in
distress can indicate such by making a continuous sounding with any
fog-signalling apparatus). It can be assumed that to avoid confusion with a
vessel making the signals for a power-driven vessel stopped and making no way
through the water, a power-driven vessel when making way should probably allow at
least ten seconds duration between single prolonged blasts, and common sense
dictates that probably no shorter duration than thirty seconds should be
necessary.
This sound
signal can be remembered as ‘TANGO’ in the Morse code. That is, one
prolonged blast followed by two short blasts, ▬.
(b) A
power-driven vessel underway but stopped and making no way through the water
shall sound at intervals of not more than 2 minutes two prolonged blasts in
succession with an interval of about 2 seconds between them.
It should be
noted that, as above, sound signals made by a vessel stopped and making no way
through the water may be sounded at shorter intervals than two minutes. This
should be the case when visibility is restricted to less than two miles, so
that the sound signal is sounded more frequently the shorter the range of
visibility.
As above, it
should be noted that whilst this sound signal should not be easy to confuse
with the signals produced by other vessels, a prolonged interval between each
signal that is composed of two prolonged blasts with two seconds duration
between them should be left in order to avoid confusion with the signal of a
vessel making way, such that there should be an interval of at least ten
seconds and preferably as much as thirty seconds between each signal.
This sound
signal can be remembered as ‘MIKE’ in the Morse code. That is, two
prolonged blasts, ▬ ▬.
(c) A
vessel not under command, a vessel restricted in her ability to manoeuvre, a
vessel constrained by her draught, a sailing vessel, a vessel engaged in
fishing and a vessel engaged in towing or pushing another vessel shall, instead
of the signals prescribed in paragraphs (a) or (b) of this Rule shall, instead
of the signals prescribed in paragraphs (a) or (b) of this Rule, sound at
intervals of not more than 2 minutes three short blasts in succession, namely
one prolonged blast followed by two short blasts.
In other
words, every vessel apart from a power-driven vessel, or a vessel aground, or a
vessel at anchor, as well as fishing vessels and vessels restricted in their
ability to manoeuvre that are at anchor, make this sound signal in restricted
visibility.
This sound
signal, as with the sound signal for a power-driven vessel making way or a
power-driven vessel stopped and making no way though the water, can be sounded
at intervals of less than two minutes. Common sense dictates that this should
be at a minimum of thirty seconds, and certainly greater than ten, although
this sound signal cannot be mistaken for any other.
This sound
signal can be remembered as ‘GOLF’ in the Morse code. That is, one
prolonged blast followed by two short blasts, ▬ ▪ ▪.
(d) A
vessel engaged in fishing, when at anchor, and a vessel restricted in her
ability to manoeuvre when carrying out her work at anchor, shall instead of the
signals prescribed in paragraph (g) of this Rule sound the signal prescribed in
paragraph (c) of this Rule.
As mentioned
before, these vessels make the ‘GOLF’ (▬ ▪ ▪) sound signal at least every two minutes instead of
the sound signals for vessels at anchor. Remember that vessels engaged in mine
clearance operations are restricted in their ability to manoeuvre, although
they display (in addition to three all-round green lights and/or three balls)
the same lights and shapes as power-driven vessels and vessels at anchor, and
make sound signals, when in restricted visibility at anchor, as other vessels
restricted in their ability to manoeuvre. To remember this rule, remember that
fishing vessels are always fishing vessel even when anchoring, and vessels
restricted in their ability to manoeuvre are always vessels restricted in their
ability to manoeuvre even when anchoring, so they make the same sound signal;
GOLF.
(e) A
vessel towed or if more than one vessel is towed the last vessel of the tow, if
manned, shall at intervals of not more than 2 minutes sound four blasts in
succession, namely one prolonged followed by three short blasts. When
practicable, this signal shall be made immediately after the signal made by the
towing vessel.
Remember that
the towed vessel only makes this sound signal if it is manned, and only the
last vessel in the tow makes this sound signal. This sound signal shall be made
immediately after the signal made by the towing vessel, which may be at
intervals more frequent than once every two minutes, but this stipulation only
exists so long as it is practicable. Therefore, it is possible that a towing
vessel and a vessel being towed will make their appropriate sound signals at
different times (or the same time) and possibly at different intervals (for
example, the towing vessel might make its sound signal once a minute, whereas
the tow makes the sound signals once every two).
Note also
that although any vessel or object must be lighted, not all towed vessels and
no towed objects need make sound signals; only if they are manned, and only the
last vessel in the tow makes the sound signal.
Note that the
last vessel in the tow, if more than one vessel is being towed, need not
necessarily be manned; but another may be. In this situation, the Rules
stipulate that none of the towed vessels shall make a sound signal. In fact,
this Rule may be interpreted to read that a vessel being towed must make the
appropriate sound signal even if it is not being manned, and that a vessel
being towed that is not manned is only exempt from making a sound signal if it
is the last vessel being towed where more than one vessel is being towed. This
is probably not the intended interpretation; probably, any towed vessel not
manned is not expected to produce the sound signal.
The towing
vessel may be smaller than the vessel being towed, or vice versa, and therefore
their sound signalling appliances may have different nominal ranges. Thus, the
sound signal of the towing vessel may be heard without the sound signal of the
towing vessel being heard (or vice versa, but that would simply be the
‘GOLF’ signal, which is less surprising.)
Only vessels
being towed make one prolonged blast followed by three short blasts. Vessels
pushed ahead do not. Remember that vessels being towed alongside are lighted as
one vessel and display sternlights; these are vessels being towed, and thus do
qualify as being able to make the sound signal (if manned) although it may be
difficult to determine which one is the last vessel in tow under certain
circumstances, that is, if vessels of equal length are being towed alongside
either side of the towing vessel. Vessels being pushed ahead are lit as one
vessel, but do not display sternlights; they also do not make sound signals.
This sound
signal can be remembered as ‘BRAVO’ in the Morse Code.
That is, one prolonged blast followed by three short blasts, ▬ ▪ ▪ ▪. Under normal
circumstances, this can be expected to be heard immediately after the sound
signal made by the towing vessel, which is ‘GOLF’ (▬ ▪ ▪). Therefore, the combined sound signal of a towing
vessel and a vessel being towed is normally considered to be ‘GOLF
BRAVO’, or ▬ ▪ ▪ ▬ ▪
▪ ▪; that is,
one prolonged blast followed by two short blasts, followed by one prolonged
blast, followed by three long blasts.
(f) When
a pushing vessel and a vessel being pushed ahead are rigidly connected in a
composite unit they shall be regarded as a power-driven vessel and shall give
the signals prescribed in paragraphs (a) or (b) of this Rule.
Vessels
thusly connected are also lighted as one vessel, as per Rule 24 (b), so it is
best to complete ignore the fact that one vessel is pushing the other and
always remember to treat them as power-driven vessels.
(g) A
vessel at anchor shall at intervals of not more than one minute ring the bell
rapidly for about 5 seconds. In a vessel of 100m or more in length the bell
shall be sounded in the forepart of the vessel and immediately after the
ringing of the bell the gong shall be sounded rapidly for about 5 seconds in
the after part of the vessel. A vessel at anchor may in addition sound three
blasts in succession, namely one short, one prolonged and one short blast, to
give warning of her position and of the possibility of collision to an
approaching vessel.
Remember that
the sound signal for a vessel at anchor is made at least once a minute, and may
be sounded more often, although common sense suggests at the very minimum there
should be an interval of at least ten seconds between making sound signals, and
preferably as much as twenty or thirty seconds.
This part of
the rule applies to vessels at anchor other than fishing vessels or any type of
vessel restricted in its ability to manoeuvre at anchor, which make the sound
signal described in part (c), that is, one prolonged followed by two short
blasts (the ‘GOLF’ signal.)
Note that
vessels of less than one hundred metres in length are not required to make the
rapid ringing of the bell in the forepart of the vessel, but vessels of more
than one hundred metres in length are obliged to make a rapid ringing of the
bell in the forepart, in addition to then making a rapid sounding of the gong
in the after part of the vessel. Do NOT think that this limit is fifty metres,
because vessels less than fifty metres at anchor need only display one
all-round white light where it can best be seen, although vessels longer than
fifty metres must show two all-round white lights, one in the fore part and one
at or near the stern and at a lower level than the one in the fore part; the
gong must be sound in the after part of the vessel if the vessel is over ONE
HUNDRED METRES in length. To help remember, recall that a vessel of more than
one hundred metres in length, when at anchor, must show all available deck
and/or working lights, and in restricted visibility, when at anchor, it must
ring the bell for five seconds in the fore part and sound the gong for five
seconds in the after part.
A vessel at
anchor may also make a sound signal with the ship’s whistle to help
indicate its position and the possibility of collision. This sound signal can
be remembered as ‘ROMEO’ in the Morse code. That is, one short
blast followed by one prolonged blast followed by one short blast, in that order,
▪ ▬ ▪.
(h) A
vessel aground shall give the bell signal and if required the gong signal
prescribed in paragraph (g) of this Rule and shall, in addition, give three
separate and distinct strokes on the bell immediately before and after the
rapid ringing of the bell. A vessel aground may in addition sound an
appropriate whistle signal.
Note that
this sound signal is either, ‘ring, ring, ring, RING x 5 seconds, ring,
ring, ring,’ or it is, ‘ring, ring, ring, RING x 5 seconds, ring,
ring, ring, GONG x 5 seconds.’ It follows the rules described in the
previous part, part (g).
A vessel
aground may also sound an appropriate whistle signal. What signal this is is not stipulated. Presumably, the signal described in Rule
34 (d), that is, five or more short blasts on the ship’s whistle, which
is used to indicate that the other vessel is taking insufficient action to
avoid a collision, is the most appropriate to use. Making one short, one
prolonged, and one short blast, that is, the warning signal for a vessel at
anchor, might seem appropriate, but it may lead to confusion, and so should be
avoided.
(i) A
vessel of 12m or more but less than 20m in length shall not be obliged to give
the bell signals prescribed in paragraphs (g) and (h) of this Rule. However, if
she does not, she shall make some other efficient sound signal at intervals of
not more than 2 minutes.
This part of
the rule stipulates that vessels between 12m and 20m in length don’t have
to make the bell signals, that is, the signals for vessels at anchor or
aground, but do have to make all the other described signals in restricted
visibility that are appropriate for a vessel of its type. It does not describe
the sound signal, but an equivalent whistle signal would not be appropriate as
it would be confused with one prolonged blast, which would indicate that the
vessel is a power-driven vessel underway and making way, not at anchor, when in
fact it is, if this part of the Rule applies. Therefore, some sound other than
the craft’s whistle should be used.
Note also
that the sound is made at least every two minutes, instead of at least every
minute. It does not need to be a single sound signal of five seconds duration,
nor three sounds, followed by one sound of five seconds, followed by three
sounds. It just needs to be ‘efficient’, which means that it does
the job, i.e. any sound whatsoever apart from a whistle.
Such a vessel
can still make these sound signals if she is able and those who have her
command are willing.
(j) A
vessel of less than 12m in length shall not be obliged to give the
above-mentioned signals but, if she does not, shall make some other efficient
sound signal at intervals of not more than 2 minutes.
This means
that a vessel of less than 12m in length doesn’t have to use a whistle or
a bell to make the appropriate sound signals, but any noise. As mentioned in
the notes for part (i), a whistle should not be used in lieu of a bell, but
there’s nothing to stipulate that the same sound shouldn’t be used
instead of both the bell and the whistle, and again, such a craft may use the
sound signals described in this Rule if able and willing.
(k) A
pilot vessel when engaged on pilotage duty may in addition to the signals
prescribed in paragraphs (a), (b) or (g) of this Rule sound an identity signal
consisting of four short blasts.
A pilot
vessel isn’t under any obligation to make this sound signal at all.
If four short
blasts are heard, it can only mean, ‘PILOT’. In addition to helping
a vessel identify the pilot vessel incoming, this sound signal informs a vessel
that she does not need to, for example, reduce her speed to the minimum she can
be kept on course if she hears another vessel’s fog signal forward of the
beam, because the pilot is coming. This allowance is made under Rule 19 part
(e), ‘Except where it has been determined that a
risk of collision does not exist…’ This, and a
few other very specific situations, are what it was talking about.
Rule
36
Signals to attract attention
If necessary to attract the attention of another vessel
any vessel may make light or sound signals that cannot be mistaken for any
other signal authorised elsewhere in these Rules, or may direct the beam of her
searchlight in the direction of the danger, in such a way as not to embarrass
any vessel. Any light to attract the attention of another vessel shall be such
that it cannot be mistaken for any aid to navigation. For the purpose of this
Rule the use of high-intensity intermittent or revolving lights, such as strobe
lights, shall be avoided.
By
‘embarrass’ this rule means ‘disrupt the safe navigation of
another vessel.’ For example, if you make a signal that is too bright, it
might remove the night vision of an officer on the bridge of another vessel,
which would hinder the ability of him to identify the lights of other vessels
and thus navigate safely; this would ‘embarrass him’.
The gist of
this rule is that you shouldn’t use lights described elsewhere in the
Rules in order to draw attention to something, or, for that matter, use a
source of illumination that might be mistaken for lights used in another rule.
The implication is that if necessary, you SHOULD make a signal to attract
attention to something that might pose a risk to another vessel.
Rule
37
Distress signals
When a vessel is in distress and requires assistance
she shall use or exhibit the signals described in annex IV to these
Regulations.
These will be
listed later and will not be repeated here. The fact that they are explicitly
mentioned in the main body of the Rules means, however, that it is very
important to recall them.
PART E – EXEMPTIONS
Rule
38
Exemptions
Any vessel (or class of vessels) provided that she
complies with the requirements of the International Regulations for Preventing
Collisions at Sea, 1960, the keel of which is laid or which is at a
corresponding stage of construction before the entry into force of these
Regulations may be exempted from compliance therewith as follows:
(a) The
installation of lights with ranges prescribed in Rule 22, until four years
after the date of entry into force of these Regulations.
(b) The
installation of lights with colour specifications as prescribed in section 7 of
annex I to these Regulations, until four years after the date of entry into
force of these Regulations.
(c) The
repositioning of lights as a result of conversion from Imperial to metric units
and rounding off measurement figures, permanent to exemption.
(d) (i) The
repositioning of masthead lights on vessels of less than 150m in length, resulting
from the prescriptions of section 3(a) of annex I to these Regulations,
permanent exemption.
(ii) The
repositioning of masthead lights on vessels of 150m or more in length,
resulting from the prescriptions of section 3(a) of annex I to these Regulations,
until nine years after the date of entry into force of these Regulations.
(e) The
repositioning of masthead lights resulting from the prescriptions of section
2(b) of annex I to these Regulations, until nine years after the date of entry
into force of these Regulations.
(f) The
repositioning of sidelights resulting from the prescriptions of section 2(g)
and 3(b) of annex I to these Regulations, until nine
years after the date of entry into force of these Regulations.
(g) The
requirements for sound signal appliances prescribed in annex III to these
Regulations, until nine years after the date of entry into force of these
Regulations.
(h) The
repositioning of all-round lights resulting from the prescription of section
9(b) of annex I to these Regulations, permanent exemption.
This rule is,
effectively, obsolete. The only ships which are likely to exceed thirty years
in age are those of historical interest; any vessel that the mariner is likely
to encounter will comply with the Rules. Only very old vessels might deviate
from the Rules slightly with respect to the position of navigational lights,
and knowing that this is what this Rule means is probably all that a mariner
will ever need to know about this Rule.
Annex I
Positioning
and technical details of lights and shapes
Most of this
annex concerns the positioning of lights. This is relevant to the seafarer, but
for the most part, the positioning of lights as described in Rule 21 and the
descriptions of the locations of the lights in PART C of the Rules should be
sufficient. Most of this section will be of more relevance to the owner or
shipbuilder.
Attention is
drawn to part 6 of this annex, which describes the minimum sizes and placement
of shapes, and part 8, which describes the nominal ranges of certain lights.
Part 13 will be of value to seafarers working on board high speed craft, or
expecting to encounter such craft.
1 Definition
The term height
above the hull means height above the uppermost continuous deck. This
height shall be measured from the position vertically beneath the location of
the light.
2 Vertical
positioning and spacing of lights
(a) On
a power-driven vessel of 20m or more in length the masthead lights shall be
placed as follows:
(i) the
forward masthead light, or if only one masthead light is carried, then that
light, at a height above the hull of not less than 6m, and, if the breadth of
the vessel exceeds 6m, then at a height above the hull not less than such
breadth, so however that the light need not be placed at a greater height above
the hull than 12m;
(ii) when two masthead lights are carried the after one shall be
at least 4.5m vertically higher than the forward one.
(b) The
vertical separation of masthead lights of power-driven vessels shall be such
that in all normal conditions of trim the after light will be seen over and
separate from the forward light at a distance of 1000m from the stem when
viewed from sea-level.
(c) The
masthead light of a power-driven vessel of 12m but less than 20m in length
shall be placed at a height above the gunwale of not less than 2.5m.
(d) A
power-driven vessel of less than 12m in length may carry the uppermost light at
a height of less than 2.5m above the gunwale. When, however, a masthead light is
carried in addition to sidelights and a sternlight or the all-round light
prescribed in Rule 23(d)(i) is carried in addition to
sidelights, then such masthead light or all0round light shall be carried at
least 1m higher than the sidelights.
(e) One
of the two or three masthead lights prescribed for a power-driven vessel when
engaged in towing or pushing another vessel shall be placed in the same
position as either the forward masthead light or the after masthead light;
provided that, if carried on the aftermast, the lowest after masthead light
shall be at least 4.5m vertically higher than the forward masthead light.
(f) (i) The
masthead light or lights prescribed in Rule 23(a) shall be so placed as to be
above and clear of all other lights and obstructions except as described in
subparagraph (ii).
(ii) When
it is impracticable to carry the all0round lights prescribed by Rule 27(b)(i) or Rule 28 below the masthead lights, they may be
carried above the after masthead light(s) or vertically in between the forward
masthead light(s) and after masthead lights(s), provided that in the latter
case the requirement of section 3(c) of this annex shall be complied with.
(g) The
sidelights of a power-driven vessel shall be placed at a height above the hull
not greater than three quarters of that of the forward masthead light. They
shall not be so low as to be interfered with by deck lights.
(h) The
sidelights, if in a combined lantern and carried on a power-driven vessel of
less than 20m in length, shall be placed not les than 1m below the masthead
light.
(i) When
the Rules prescribed two or three lights to be carried in a vertical line, they
shall be spaced as follows:
(i) on
a vessel of 20m in length or more such lights shall be spaced not less than 2m
apart, and the lowest of these lights shall, except where a towing light is
required, be placed at a height of not less than 4m above the hull;
(ii) on a
vessel of less than 20m in length such lights shall be spaced not less than 1m
apart and the lowest of these lights shall, except where a towing light is
required, be placed at a height of not less than 2m above the gunwale;
(iii) when three lights are carried they shall be equally spaced.
(j) The
lower of the two all0round lights prescribed for a vessel when engaged in
fishing shall be at a height above the sidelights not less than twice the
distance between the two vertical lights.
(k) The
forward anchor light prescribed in Rule 30(a)(i), when
two are carried, shall not be less than 4.5m above the after one. On a vessel
of 50m or more in length this forward anchor light shall be placed at a height
of not less than 6m above the hull.
3 Horizontal
positioning and spacing of lights
(a) When
two masthead lights are prescribed for a power-driven vessel the horizontal
distance between them shall not be less than one half of the length of the
vessel but need not be more than 100m. The forward light shall be placed not
more than one quarter of the length of the vessel form the stem.
(b) On
a power-driven vessel of 20m or more in length the sidelights shall not be
placed in front of the forward masthead lights. They shall be placed at or near
the side of the vessel.
(c) When
the lights prescribed in Rule 27(b)(i) or
Rule 28 are placed vertically between the forward masthead light(s) and the
after masthead light(s) these all-round lights shall be placed at a horizontal
distance of not less than 2m from the fore-and-aft centreline of the vessel in
athwartship direction.
(d) When
only one masthead light is prescribed for a power-driven vessel, this light
shall be exhibited forward of amidships; except that a vessel of less than 20m
in length need not exhibit this light forward of amidships but shall exhibit it
as far forward as is practicable.
4 Details
of location of direction-indicating lights for fishing vessels, dredgers, and
vessels engaged in underwater operations
(a) The
light indicating the direction of the outlying gear from a vessel engaged in
fishing as prescribed in Rule 26(c)(iii) shall be
placed at a horizontal distance of not less than 2m and not more than 6m away
from the two all-round red and white lights. This light shall be placed not
higher than the all-round white light prescribed in Rule 26(c)(i)
and not lower than the sidelights.
(b) The
lights and shapes on a vessel engaged in dredging or underwater operations to
indicate the obstructed side and/or the side on which it is safe to pass, as
prescribed in Rule 27(d)(i) and (ii), shall be placed
at the maximum practical horizontal distance, but in no case less than 2m, from
the lights or shapes prescribed in Rule 27(b)(i) and (ii). In no case shall the
upper of these lights or shapes be at a greater height than the lower of the
three lights or shapes prescribed in Rule 27(b)(i) and
(ii).
5 Screens
for sidelights
The sidelights of vessels of 20m or more in length
shall be fitted with inboard screens painted matt black, and meeting the
requirements of section 9 of this annex. On vessels of less than 20m in length
the sidelights, if necessary to meet the requirements of section 9 of this
annex, shall be fitted with inboard matt black screens. With a combined
lantern, using a single vertical filament and a very narrow division between
the green and red sections, external screens need not be fitted.
6 Shapes
(a) Shapes
shall be black and of the following sizes:
(i) a ball shall have a diameter of not less than 0.6 m;
(ii) a cone shall have a base diameter of not less than 0.6, and
a height equal to its diameter;
(iii) a cylinder shall have a diameter of at least 0.6m and a heigh of twice its diameter;
(iv) a diamond shape shall consist of two cones as defined in
(ii) above having a common base.
(b) The
vertical distance between shapes shall be at least 1.5m.
(c) In
a vessel of less than 20m in length shapes of less dimensions but commensurate
with the size of the vessel may be used and the distance apart may be
correspondingly reduced.
7 Colour
specification of lights
The chromaticity of all navigation lights shall
conform to the following standards, which lie within the boundaries of the area
of the diagram specific for each colour by the International Commission on
Illumination (CIE).
The boundaries of the area for each colour are given
by indicating the corner co-ordinates, which are as follows:
(i) White
x 0.525 0.525 0.452 0.310 0.310 0.443
y 0.382 0.440 0.440 0.348 0.283 0.382
(ii) Green
x 0.028 0.009 0.300 0.203
y 0.385 0.723 0.511 0.356
(ii) Red
x 0.680 0.660 0.735 0.721
y 0.320 0.320 0.265 0.259
(ii) Yellow
x 0.612 0.618 0.575 0.575
y 0.382 0.382 0.425 0.406
8 Intensity
of lights
(a) The
minimum luminous intensity of lights shall be calculated by using the formula:
I = 3.43 × 106 × T
× D2 × K-D
where I is
luminous intensity in candelas under service conditions,
T is
threshold factor 2 × 10-7
lux,
D is
range of visibility (luminous ranges) of the light in nautical miles,
K is
atmospheric transmissivity.
For
prescribed lights the value of K shall be 0.8, corresponding to a
meteorological visibility of approximately 13 nautical miles.
(b) A
selection of figures derived from the formula is given in the following table:
Range of visibility (luminous range) of light
nautical miles |
Luminous intensity of light in candelas for K = 0.8 |
D |
I |
1 |
0.9 |
2 |
4.3 |
3 |
12 |
4 |
27 |
5 |
52 |
6 |
94 |
NOTE: The maximum luminous
intensity of navigation lights should be limited to avoid undue glare. This shall
not be achieved by a variable control of the luminous intensity.
9 Horizontal
sectors
(a) (i) In
the forward direction, sidelights as fitted on the vessel shall show the
minimum required intensities. the intensities shall
decrease to reach practical cut-off between 1° and 3° outside the
prescribed sectors.
(ii) For
sternlights and masthead lights and at 22.5° abaft the beam for sidelights,
the minimum required intensities shall be maintained over the arc of the
horizon for up to 5° within the limits of the sectors prescribed in Rule
21. From 5° within the prescribed sectors the intensity may decrease by 50%
up to the prescribed limits; it shall decrease steadily to reach practical
cut-off at not more than 5° outside the prescribed sectors.
(b) (i) All-round
lights shall be so located as not to be obscured by masts, topmasts or
structures within angular sectors of more than 6°, except anchor lights
prescribed in Rule 30, which need not be placed at an impracticable height
above the hull.
(ii) If it
is impracticable to comply with paragraph (b)(i) of
this section by exhibiting only one all-round light, two all-round lights shall
be used suitably position or screened so that they appear, as far as
practicable, as one light at a distance of one mile.
10 Vertical
sectors
(a) The
vertical sectors of electric lights fitted, with the exception of lights on
sailing vessels underway, shall ensure that:
(i) at least the required minimum intensity is maintained at all
angles from 5° above to 5° below the horizontal;
(ii) at least 60% of the required minimum intensity is maintained
from 7.5° above to 7.5° below the horizontal.
(b) In
the case of sailing vessels underway the vertical sectors of electric lights as
fitted shall ensure that:
(i) at least the required minimum intensity is maintained at all
angles from 5° above to 5° below the horizontal;
(ii) at least 50% of the required minimum intensity is maintained
from 25° above to 25° below the horizontal.
(c) In
the case of lights other than electric these specifications shall be met as
closely as possible.
11 Intensity
of non-electric lights
Non-electric lights shall so far as practicable comply
with the minimum intensities, as specified in the table given in section 8 of
this annex.
12 Manoeuvring
light
Notwithstanding the provisions of paragraph 2(f) of
this annex, the manoeuvring light described in Rule 34(b) shall be placed in
the same for-and-aft vertical plane as the masthead light or lights and, where
practicable, at a minimum height of 2m vertically above the forward masthead
light, provided that it shall be carried not less than 2m vertically above or
below the after masthead light. On a vessel where only one masthead light is
carried, the manoeuvring light, if fitted, shall be carried where it can best
be seen, not less than 2m vertically apart from the masthead light.
13 High-speed
craft*
(a) The
masthead light of high-speed craft may be placed at a height related to the
breadth of the craft lower than that prescribed in paragraph 2(a)(i) of this annex, provided that the base angle of the
isosceles triangles formed by the sidelights and masthead light, when seen in
end elevation is not less than 27°.
(b) On
high-speed craft of 50m or more in length, the vertical separation between the
foremast and mainmast light of 4.5m required by paragraph 2(a)(ii)
of this annex may be modified provided that such distance shall not be less
than the value determined by the following formula:
y = (a + 17Ψ)C + 2
1000
where: y is
the height of the mainmast light above the foremast light in metres;
a is
the height of the foremast light above the water surface in service condition
in metres;
Ψ is
the trim in service condition in degrees;
C is
the horizontal separation of masthead lights in metres.
* Refer to the International Code of Safety for
High-Speed Craft, 1994 and the International Code of Safety for High-Speed
Craft, 2000.
14 Approval
The construction of lights and shapes and the installation
of lights on board the vessel shall be to the satisfaction of the appropriate
authority of the State whose flag the vessel is entitled to fly.
Annex II
Additional
signals for fishing vessels fishing in close proximity
It is in no
way unusual to encounter fishing vessels working as part of a fleet. Not that
this rule only applies to such vessels; none of these signals need be used by
vessels operating alone. Seafarers will need to be as familiar with these Rules
as well as those for fishing vessels. Note also that all of these Rules apply
to trawlers, and no other types of vessel.
1 General
The lights mentioned herein shall, if exhibited in
pursuance of Rule 26(d), be placed where they can best be seen. They shall be
at least 0.9m apart but at a lower level than lights prescribed in Rule 26(b)(i) and (c)(i). The lights shall be visible all round the
horizon at a distance of at least 1 mile but at a lesser distance than the
lights prescribed by these Rules for fishing vessels.
Rule 22
describes the visibility of lights. For vessels of less than 12m in length,
sidelights have a nominal visibility of 1 mile; for vessels more than 12m in
length, the minimum nominal range of visibility is 2 miles, and for vessels
greater than 50m in length, the minimum nominal range of any light is 3 miles.
Therefore, the maximum intensity for the lights described by this annex is 1
mile for vessels of less than 12m in length, 2 miles for vessels greater than
12m in length, and 3 miles for vessels greater than 50m in length. The minimum
nominal range of visibility of those lights is 1 mile.
2 Signals
for trawlers
(a) Vessels
of 20m or more in length when engaged in trawling, whether using demersal or
pelagic gear, shall exhibit:
(i) when shooting their nets:
two white lights in a vertical line;
(ii) when hauling their nets:
one white light over one red light in a vertical line;
(iii) when the net has come fast upon an obstruction:
two red lights in a vertical line.
The International
Code of Signals flags for the activity described in parts (i), (ii) and (iii)
respectively are “Z” or “ZULU”, “G” or
“GOLF”, and “P” or “PAPA”.
(b) Each
vessel of 20m or more in length engaged in pair trawling shall exhibit:
(i)
by night, a searchlight directed forward and in the
direction of the other vessel of the pair;
(ii) when shooting or hauling their nets or when the nets have
come fast upon an obstruction, the lights prescribed in 2(a) above.
(c) A
vessel of less than 20m in length engaged in trawling, whether using demersal
or pelagic gear or engaged in pair trawling, may exhibit the lights prescribed
in paragraphs (a) or (b) of this section, as appropriate.
3
Signals for purse seiners
Vessels engaged in fishing with purse seine gear may
exhibit two yellow lights in a vertical line. These lights shall flash
alternately every second and with equal light and occultation duration. These
lights may be exhibited only when the vessel is hampered by its fishing gear.
A purse
seiner is a type of trawler, although
it is not stated so here. The lights, although they are literally flashing, are
not to be considered ‘flashing lights’ as defined by Rule 21 part
(f).
Annex III
Technical
details of sound signal appliances
As the title
suggests, this annex is largely technical, and will be of more value to the
shipbuilder than to the seafarer, who has no means of accurately measuring
sound at sea. Part 1 (c) is of particular value to the seafarer, since it
describes the nominal ranges of whistles, which is of particular importance as
relates to Rule 35, and PART D of the Rules in general.
1 Whistles
(a) Frequencies and range of audibility
The fundamental frequency of the signal shall lie within
the range 70-700 Hz. The range of audibility of the signal from a whistle shall
be determined by those frequencies, which may include the fundamental and/or
one or more higher frequencies, which lie within the range 180-700 Hz (±
1%) for a vessel of 20m or more in length, or 180-2100 Hz (± 1%) for a
vessel of less than 20m in length and which provide the sound pressure levels
specified in paragraph 1(c) below.
(b) Limits of fundamental frequencies
To ensure a wide variety of whistle characteristics,
the fundamental frequency of a whistle shall be between the following limits:
(i) 70-200
Hz, for a vessel 200m or more in length;
(ii) 130-350
Hz, for a vessel 75m but less than 200m in length;
(iii) 250-700
Hz, for a vessel less than 75m in length.
(c) Sound signal intensity and range of
audibility
A whistle fitted in a vessel shall provide, in the
direction of maximum intensity of the whistle and at a distance of 1m from it,
a sound pressure level in at least one ⅓-octave band within the range of
frequencies 180-700 Hz (± 1%) for a vessel of 20m or more in length, or
180-2100 Hz (± 1%) for a vessel of less than 20m in length, of not less
than the appropriate figure given in the table below.
Length of vessel in metres |
⅓-octave band level at 1m in dB referred to
2×10-5N/m2 |
Audibility range in nautical miles |
200 or more |
143 |
2 |
75 but less
than 200 |
138 |
1.5 |
20 but less
than 75 |
130 |
1 |
Less than 20 |
120* |
0.5 |
|
115† |
|
|
111‡ |
|
* When
the measured frequencies lie within the range 180-450 Hz
† When
the measured frequencies lie within the range 180-450 Hz
‡ When
the measured frequencies lie within the range 180-450 Hz
The range of audibility in the table above is for
information and is approximately the range at which a whistle may be heard on
its forward axis with 90% probability in conditions of still air on board a
vessel having average background noise level at the listening posts (taken to
be 68 dB in the octave band centred on 250 Hz and 63 dB in the octave band
centred on 500 Hz)
In practice the range at which a whistle may be heard
is extremely variable and depends critically on weather conditions; the values
given can be regarded as typical but under conditions of strong wind or high
ambient noise level at the listening post the range may be much reduced.
(d) Directional properties
The sound pressure level of a directional whistle
shall be not more than 4 DB below the prescribed sound pressure level on the
axis at any direction in the horizontal plane within ±45° of the
axis. The sound pressure level at any other direction in the horizontal plane
shall be not more than 10 dB below the prescribed sound pressure level on the
axis, so that the range in any direction will be at least half the range on the
forward axis. The sound pressure level shall be measured in that ⅓-octave
band which determines the audibility range.
(e) Positioning of whistles
When a directional whistle is to be used as the only
whistle on a vessel, it shall be installed with its maximum intensity directed
straight ahead.
A whistle shall be placed as high as practicable on a
vessel, in order to reduce interception of the emitted sound by obstructions
and also to minimise hearing damage risk to personnel. The sound pressure level
of the vessel’s own signal at listening posts shall not exceed 110 dB (A)
and so far as practicable should not exceed 100 dB (A).
(f) Fitting of more than one whistle
If whistles are fitted at a distance apart of more
than 100m, it shall be so arranged that they are not sounded simultaneously.
(g) Combined whistle systems
If due to the presence of obstructions the sound field
of a single whistle or one of the whistles referred to in paragraph I(f) above
is likely to have a zone of greatly reduced signal level, it is recommended
that a combined whistle system be fitted so as to overcome this reduction. For
the purposes of the Rules a combined whistle system is to be regarded as a
single whistle. The whistles of a combined system shall be located at a
distance apart of not more than 100m and arranged to be sounded simultaneously.
the frequency of any one whistle shall differ from
those of the others by at least 10 Hz.
2
(a) Intensity of signal
A bell or gong, or other device having similar sound
characteristics shall produce a sound pressure level of not less than 110 dB at
a distance of 1m from it.
(b) Construction
Bells and gongs shall be made of corrosion-resistant
material and designed to give a clear tone. The diameter of the mouth of the
bell shall be not less than 300mm for vessels of 20m or more in length. Where
practicable, a power-driven bell striker is recommended to ensure constant
force but manual operation shall be possible. The mass of the striker shall be
not less than 3% of the mass of the bell.
3 Approval
The construction of sound signal appliances, their
performance and their installation on board the vessel shall be to the
satisfaction of the appropriate authority of the State whose flag the vessel is
entitled to fly.
Annex IV
Distress
signals
The distress
signals used by vessels at sea are of vital importance to a vessel in distress!
All seafarers are required to be able to recognise these signals, and since
lives may be at stake, these signals are extremely important. They simply need
to be memorised.
1 The
following signals, used or exhibited either together
or separately, indicate distress and need of assistance:
(a) a gun or other explosive signal fired at intervals of about
a minute;
(b) a continuous sounding with any fog-signalling apparatus;
(c) rockets or shells, throwing red stars fired one at a time at
short intervals;
(d) a signal made by radiotelegraphy or by any other signalling
method consisting of the group ▪ ▪ ▪ ▬ ▬ ▬ ▪ ▪ ▪ (SOS) in the Morse Code;
(e) a signal made by radiotelephony consisting of the spoken
word “Mayday”;
(f) the International Code of Signal of distress indicated by
N.C.;
(g) a signal consisting of a square flag having above or below
it a ball or anything resembling a ball;
(h) flames on the vessel (as from a burning tar barrel, oil
barrel, etc.);
(i) a rocket parachute flare or a hand-flare showing a red
light;
(j) a smoke signal giving off orange-coloured smoke;
(k) slowly and repeatedly raising and lowering arms outstretched
to each side;
(l) the radiotelegraph alarm signal;
(m) the radiotelephone alarm signal;
(n) signals transmitted by emergency position-indicating radio
beacons;
(o) approved signals transmitted by radiocommunication systems,
including survival craft radar transponders.
2 The
use or exhibition of any of the foregoing signals except for the purpose of
indicating distress and need of assistance and the use of other signals which
may be confused with any of the above signals is prohibited.
3 Attention
is drawn to the relevant sections of the International Code of Signals, the
Merchant Ship Search and Rescue Manual and the following signals:
(a) a piece of orange-coloured canvas with either a black square
and a circle or other appropriate symbol (for identification from the air);
(b) a dye marker.