Lights and Shapes

Lights and Shapes


Be aware of the following items in Collision Regulations.

A "masthead light" means a white light placed over the fore and aft centerline of a pleasure craft showing an unbroken light over an arc of the horizon of 225 degrees and so fixed as to show the light from right ahead to 22.5 degrees abaft the beam on either side of a pleasure craft.

"Sidelights" means a green light on the starboard side and a red light of the port side each showing an unbroken light over an arc of the horizon of 112.5 degrees and so fixed as to show the light from right ahead to 22.5 degrees abaft the beam on its respective side. Memory aid: port wine is red.

"Sternlight" means a white light placed as nearly practical at the stern showing an unbroken light over an arc of the horizon of 135 degrees and so fixed as to show the light 67.5 degrees from the right aft on each side of a pleasure craft.

"All-round light", white, means a white light showing an unbroken light over an arc of the horizon of 360 degrees.

"All-round light", green, means a green light showing an unbroken light over an arc of the horizon of 360 degrees.

"All-round light", red, means a red light showing an unbroken light over an arc of the horizon of 360 degrees.

"Towing light" means a yellow light having the same characteristics as the "Sternlight" defined above and identifies a vessel engaged a towing operation.

"Flashing light" means a light flashing at regular intervals at a frequency of 120 flashes or more per minute.




"Special flashing light" means a yellow light flashing at regular intervals at a frequency of 50 to 70 flashes per minute, placed as far forward and as nearly as practicable on the fore and aft centreline of a vessel and showing an unbroken light over an arc of the horizon of not less than 180 degrees nor more than 225 degrees and so fixed as to show the light from right ahead to abeam and not more than 22.5 degrees abaft the beam on either side of the vessel.




"Blue flashing light" means a blue all-round light flashing at regular intervals at a frequency of 50 to 70 flashes per minute.

Navigation lights

Navigation lights

Navigation lights required on most power driven vessels operating on water by night (sunset to sunrise) and in times of reduced visibility are shown below. Refer to the Shipping (Distress Signals & Prevention or Collisions) Regulations 1988, for full details.

NAVIGATION RULES

NAVIGATION RULES

PART A - GENERAL
Rule 1 - Application
Rule 2 - Responsibility
Rule 3 - General Definitions
PART B - STEERING AND SAILING RULES

Section | Subpart 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 | Vessel Traffic Services

Section | Subpart 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 | Subpart III - Conduct of Vessels in Restricted Visibility
Rule 19 - Conduct of Vessels in Restricted Visibility

PART C - LIGHTS AND SHAPES
Rule 20 - Application
Rule 21 - Definitions (Navigation Lights Arcs of Visibility)
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 Maneuver
Rule 28 - Vessels Constrained by Their Draft
Rule 29 - Pilot Vessels
Rule 30 - Anchored Vessels and Vessels Aground
Rule 31 - Seaplanes

PART D - SOUND AND LIGHT SIGNALS

Rule 32 - Definitions
Rule 33 - Equipment for Sound Signals
Rule 34 - Maneuvering 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

Action to Avoid Collision

Action to Avoid Collision
If your are going to make an alteration of course make sure its an early and bold alteration as long as you have plenty sea room

Every alteration must be big enough so the other vessel can see it on his radar

A series of small alterations should be avoided

When making an alteration of course, make sure you don't place your vessel into a close quarter situation/risk of collision with another vessel

When taking action to avoid collision you can do one of 4 things

(1) Make an early and bold alteration of course

(2)slow your vessel down

(3)stop your vessel

(4)come astern with your vessel

If you are ever in doubt your best thing to do is stop your vessel until the risk of collision is past (also gives you more thinking time as to what you can do)

After making an alteration of course, take more bearings to make sure the risk of collision/close quarter situation is past

If you're on a collision course
If you're the stand-on vessel you may alter course as long as your not in a close quarters situation, but if in a close quarters situation you shall alter course (Never get into a close quarter situation if you can help it)

Rule of thumb

From 8 to 12 miles - this is your plotting distance to find out if risk of collision/close quarters situation exists

From 4 to 8 miles - this is your/other vessels action area

below 4 miles - close quarters situation (out in the open sea, you should have no vessel within 4 miles)

What you have to do in any situation


(1) Take a series of compass, radar and visual bearing to see if a "Risk of Collision/close quarters situation exists"

(2) Figure out who the giveway/stand-on vessel is

(3) If your the stand-on vessel then use (A) below

(4) If your the giveway vessel then use (B) below

(5) If the giveway vessel is standing on then sound 5 or more short and rapid blasts on the ships whistle or flash your masthead light rapidly 5 or more times, if you get no response then use (C) below

(A) Stand-on with caution, maintaining your course and speed, keep taking bearings to make sure the giveway vessel givesway

(B) As long as there is pleanty sea-room, make an early and bold alteration towards the giveway vessel, give him plenty sea-room, if not a lot of sea-room stop your vessel and let him pass

(C) Make an bold alteration away from this vessel (he could be a pirate vessel)

Basics of Sea Collision Regulations: Lights, Shapes, and Sound Signals

Basics of Sea Collision Regulations: Lights, Shapes, and Sound Signals

This last article in the series explains lights, shapes and sound signals used on ships at sea. These indicate the length and type of ship to other ships and helps navigators to determine their responsibility- and, therefore, actions, under the Rules of the Road.

Why do we need lights and shapes?

As earlier articles have shown, there exists, under the sea rules of the road Colregs, responsibility between vessels- a sailing vessel, for example, must keep clear of a vessel constrained by her draft. But how does she know that this is so? It becomes easy once we realise that the vessel constrained by her draft and the sailing vessel must both display typical lights and shapes. It then becomes easy to determine which is the ‘give way’ vessel, and action is taking accordingly under the Rules of the Road.

The heights and arcs of visibility of each light are prescribed under the rules, and are subject to survey and approval during the construction of the ship. The distance at which each light can be seen at sea is also fixed; for example, a masthead light must be visible at six nautical miles. This is true for all lights, shapes and sound signals for all ships worldwide.

Normal Lights & Shapes for Power Driven Vessel

A normal power driven vessel displaysstrapping and lashing solutions one way lashing and cargo securing


A mastlight high on her forward mast
A second mastlight even higher on her after mast if the length of the vessel is more than 50 metres.
A sternlight on her stern
Two sidelights, a green one on her starboard (right) side and a red one on her port (left) side

At anchor, a power driven vessel shows an all round (360 degree) light. When she is more than 50 metres in length, she shows two all round lights, with the forward one being higher than the one near her stern.



Lights on Other Vessels

Typical lights Click on the diagram on the left; it gives you some typical lights that are displayed by different vessels at night.

It is important to realise that most 'special lights' are shown in addition to the normal running lights of a power driven vessel when a vessel is under mechanical power. For example, the vessel constrained by her draft shows three all round red lights in addition to the normal masthead light(s), sidelights and sternlight.

Note also that a vessel aground (where she has run into the seabed and is fast there) shows two red lights in addition to her anchor lights.

A sailing vessel that is moving shows the same sidelights and sternlight as a powerboat, but does not show a masthead light. A vessel with sails up, but also being propelled by machinery must show the power-driven vessel 'running lights'

A fishing vessel is defined as one engaged in fishing with nets, lines, trawls, or other gear that restricts her ability to manoeuvre. The diagram shows a trawler.

A tug towing a barge is not normally considered to be restricted in her ability to manoeuvre. A tug towing another vessel does not show normal masthead lights, but must show two masthead lights instead one vertically above the other. (normal masthead lights are horizontally displaced, but not in the case of a tug). If the length of the tow is more than 200 metres, it must display three masthead lights vertically disposed. In addition, it displays sidelights and a sternlight. It also must display an all round towing light at the stern, above the sternlight.

A vessel being towed does not display masthead lights, but sidelights and a sternlight.

A towing vessel seen from far away can be confusing to a first time mariner, and care must be exercised.
Shapes

What lights indicate by night, shapes indicate in the daytime. Shapes are, typically, 'a ball' (spherical), a cylinder, a diamond, a cone etc. As with lights, their shape, colour and size is prescribed under the rules. These are normally hoisted on a mast so that they can be seen from afar by other vessels.

Some typical shape configurations:

A normal power driven vessel shows nothing special at daytime
A vessel at anchor shows a black ball at her forward end on the forecastle.
A vessel not under command shows two black balls in a vertical line on her main (highest) mast
A vessel restricted in her ability to manoeuvre shows two black balls separated by a diamond.

Some other typical shape configurations can be seen in the diagram below, along with the kind of ship they represent.


Shapes

What lights indicate by night, shapes indicate in the daytime. Shapes are, typically, 'a ball' (spherical), a cylinder, a diamond, a cone etc. As with lights, their shape, colour and size is prescribed under the rules. These are normally hoisted on a mast so that they can be seen from afar by other vessels.

Some typical shape configurations:

A normal power driven vessel shows nothing special at daytime
A vessel at anchor shows a black ball at her forward end on the forecastle.
A vessel not under command shows two black balls in a vertical line on her main (highest) mast
A vessel restricted in her ability to manoeuvre shows two black balls separated by a diamond.

Some other typical shape configurations can be seen in the diagram below, along with the kind of ship they represent.

Other Examples of Shapes and their Disposition
shapes

There are only three types of sound-signal equipment mentioned in the Rules - whistle, bell, and gong, with the latter only required on vessels 100 meters or more in length. As with everything else, the specifications of the equipment are prescribed in the rules. The whistle and gong are used by larger vessels when anchored in poor visibility in addition to the normal sound signals.

A 'short blast' is a signal on the foghorn (or whistle) of about one second duration.
A 'long blast' is of four to six second duration
When moving, a ship may use the following basic signals to 'contact' other ships
One short blast- I am turning to starboard (my right)
Two short blasts- I am turning to port (my left)
Three short blasts- I am going astern (backwards)
One long blast- I am moving (usually used in fog or at blind turns)
One long blast followed by two short ones: I am not under command
Five short rapid blasts: Please declare your intentions (also used to say, 'what are you doing?, or get out of the way'

Other kinds of vessels have similar signals identified in the rules, which must be followed.

Conclusion and Resources

Important: This series has been a basic primer on the Colregs. The rules can be very complex and a navigator is well advised to devote considerably time to this safety-critical issue. For further reading, search for Colregs on the internet, where the full text of the rules is available.

Basics of the Sea: Rules of the Road - In any Condition of Visibility.

Basics of the Sea: Rules of the Road - In any Condition of Visibility.

It is pretty easy to avoid collision of vehicles on road by applying brakes and being a little vigilant. But how do we avoid collisions at sea when gigantic structures tend to collide? Learn inside this article

Part B of the ROR/Navigation Rules of the Road

Part B of the Collision Regulations (or Colregs) is divided into three Sections. The first section deals with rules in all conditions of visibility, whether normal or restricted (by fog, rain or any other reason)

Rule 5 covers lookouts, a commonsense precaution that is often neglected- basically, this is ‘keeping an eye out for other ships and dangers’. The lookout(s) must be able to hear as well as see other ships and dangers. (‘hear’ includes listening to their foghorn, by which ships alert each other of their intentions at sea, using basic morse code in a manner also prescribed by the Colregs.) Note that a lookout is required at all times, even at anchor.

Just like your cars on the road, a critical rule requires a ship to maintain safe speed at all times. This can vary depending on circumstances, eg busy shipping lanes, poor visibility, other hazards etc.

Some sea rules of the road cover the proper use and interpretation of radar and the determining of a risk of collision (will the ship I am seeing collide with me or pass dangerously close?).

Other logical rules include the requirement that if some action is required of you, such as a change of course or speed, it should be made soon to be effective, and large enough to be obvious to the other vessel. A change of course is usually more obvious than a change of speed, but the give way vessel must slow down if required for safety.
Another rule requires a ship to stay on the right (starboard) side of a narrow waterway- the equivalent of driving on the right side of a road on land.


How do you know if there is risk of collision?

Rule 10. Traffic Seperation Schemes (TSS)

A very important rule that covers areas of the oceans that have been internationally agreed to have a TSS covering them. A TSS is, essentially, a ‘road map’ marked on a navigators chart, which shows roads (or lanes), the lane a ship must take when going in a given direction and how she must behave within the TSS. The TSS coverage areas are usually areas of high traffic density; hence this attempt to ‘regulate’ the traffic. Ships are not bound to use the TSS all the time, but whenever they do- or are in the vicinity of a TSS, they must follow Rule 10.

Some salient features of this rule:

All vessels crossing the TSS (coming from an area outside it and going to an area outside it) must cross the TSS at right angles to the traffic lane, presenting a full profile to ships within the lane. (Similar to a crossroads like situation).

No vessel should “impede the safe passage of a power driven vessel following a traffic lane." The aim should be to cross as quickly as possible.

Note that the rules discussed here apply in any condition of visibility. The next article will discuss rules which apply only when vessels can see each other.

There are many ways to determine this, including automatic ones like the Radar (ARPA or Automated Radar Plotting Aids) which tell you how close a ship will pass to you- or, indeed, collide with you- provided none of you makes any changes to course and speed and after how long, besides other information.

The easiest way is to take compass bearings of the other vessel. If there is no appreciable change over time (say, six minutes), then a risk of collision exists and action must be taken by the give way vessel.

Basics of the Navigation Rules: When ships can see each other, and when they can't

Basics of the Navigation Rules: When ships can see each other, and when they can't


This third article in the series explains how ships behave when they can see each other and when visibility is reduced. Note that night is not considered bad or restricted visibility for the Colregs. I will also explain the term ‘responsibilities between vessels’

Introduction

We have been studying about the navigation rules of the road in our last two articles. In this article we will proceed to learn about the regulations that govern situations whenever two ships are in proximity and either are visible to each other or are invisible ships due to bad weather conditions. Learn about these interesting scenarios below.
Vessels in Sight of One another, Crossing

crossing

When two ships meet, and if risk of collision exists (see previous article in series), the Collision rules specify that unless one is overtaking the other, they are ‘crossing’. If they are crossing, the ship that has the other on her starboard side (right side, and this ship is the ‘give way’ vessel) will keep out of the way of the other vessel, which is the ‘stand on’ vessel, which must maintain its course and speed.

The give way vessel can alter speed or alter course, or indeed, a combination of the above. Usually in the open sea, an alteration of course is sufficient, as can be seen in the diagram.

If required, stipulated signals or sounds (foghorn) will be made by the vessels. For example, one short blast on the foghorn (or one flash of a light at night) will indicate “I am altering course to starboard” )

In any case, the give way vessel will avoid crossing ahead of the other vessel. At sea, a starboard alteration of course is invariably made in such situations.

If both vessels are head on (on reciprocal courses) each will alter course to starboard and keep out of the way of the other.


Vessels in sight of one another, overtaking.

An overtaking vessel must keep out of the way of a ship being overtaken. It can overtake on either side.

Sound and light signals are prudent to indicate to the vessel which side the intention is to overtake on. The vessel being overtaken will signal agreement with specified sound/light signals, foghorn and/or light.

Responsibilities between vessels. (see earlier articles for definitions)

A normal power driven vessel should keep clear of a vessel restricted in any way, whether in her ability to manoeuvre, not under command, fishing or sailing.

A sailing vessel must keep clear of all except a normal power driven vessel.

A fishing vessel (when actually fishing) should keep clear of a vessel restricted in her ability to manoeuvre or a vessel not under command.

Any vessel except a vessel not under command should keep clear of a vessel that is constrained by her draft. This ship should exercise extra caution.

A seaplane should keep clear of everything.

Conduct of vessels in restricted visibility

All ships of any kind should proceed at a safe speed in mist, fog or other such conditions that restrict visibility. They should be ready for immediate manoeuvre. They should stop engines and even go astern (reverse) if required.

If another vessel is detected on radar, and if there is risk of collision, all ships should take action well in advance. If required to alter course, they should avoid an alteration of course to port for a vessel that they are not overtaking. If they are overtaking, they should avoid an alteration of course towards a vessel that they are overtaking.

Fog signals are highly recommended in such situations. It is also imperative to navigate with extreme caution in fog, especially when other ships are close by and cannot be seen.