Colregs 1972 Made Easy

COLREGs 1972: Made Easy

About this Made Easy It’s our pleasure to introduce to mariners this ‘Made Easy’ on RoR. We felt the necessity of an abridged version of RoR-explanation for the benefit of the mariners, especially for junior deck officers. By publishing this Made Easy, a dream has come true; the complete work has not been accomplished yet though. We’ve prepared it based on own expertise and long research works. We’ve, so far, covered Rule-1 to Rrule-19 and intend to add the remaining rules soon. Moreover, we intend to publish a book on this in future. We’ve tried our best to prepare it without mistakes. However, no write-up is flawless. We would appreciate your feedback on how to improve this Made Easy. Please advise us if you find any mistakes in this Made Easy. No person or organization is allowed to copy or reproduce the contents of this Made Easy without prior permission from the writers. Your feedback is our inspiration. Please send your feedback to [email protected] . Preface The International Regulations for Preventing Collisions at Sea 1972 (Colregs) are published by the International Maritime Organization (IMO) and set out, among other things, the "Rules of the Road" or navigation rules to be followed by ships and other vessels at sea to prevent collisions between two or more vessels. The COLREGs are derived from a multilateral treaty called the ‘Convention on the International Regulations for Preventing Collisions at Sea’. History Prior to the development of a single set of international rules and practices, there existed separate practices and various conventions and informal procedures in different parts of the world, as advanced by various maritime nations. As a result, there were inconsistencies and even contradictions that gave rise to unintended collisions. Vessels’ navigation lights for operating in darkness as well as navigation marks also were not standardized, giving rise to dangerous confusion and ambiguity between vessels at risk of colliding. 1840 in London, the Trinity House drew up a set of regulations which were enacted by Parliament in 1846.

1858 in the UK, coloured sidelights were recommended for sailing vessels and fog signals were required to be given by steam vessels on the ships whistle and by sailing vessels on the fog horn or bell, while a separate but similar action was also taken in the United States.

In 1863, a new set of rules drawn up by the British Board of Trade, in consultation with the French government, came into force. By 1864, the regulations (or Articles) had been adopted by more than thirty maritime countries, including Germany and the United States. In 1867, Thomas Gray, assistant secretary to the London Maritime Department of Trade, wrote The Rules of the Road, a pamphlet that became famous for its well-known mnemonic verses. In 1880, the 1863 Articles were supplemented with whistle signals and in 1884 a new set of international regulations was implemented. In 1889, the United States convened the first international maritime conference in Washington, D.C. The resulting rules were adopted in 1890 and came into effect in 1897. Some minor changes were made during the 1910 Brussels Maritime Conference and some rule changes were proposed, but never ratified, at the 1929 International Conference on Safety of Life at Sea (S.O.L.A.S.) with the recommendation that the direction of a turn be referenced by the rudder instead of the helm or tiller being informally agreed by all maritime nations in 1935. The 1948 S.O.L.A.S. International Conference made several recommendations, including the recognition of R.A.D.A.R., these were eventually ratified in 1952 and became effective in 1954. Further recommendations were made by a S.O.L.A.S. Conference in London in 1960 which became effective in 1965 The International Regulations for Preventing Collisions at Sea were adopted as a Convention of the International Maritime Organization on 20 October 1972 and entered into force on 15 July 1977. They were designed to update and replace the Collision Regulations of 1960.

Amendments 1981: Rule 10 was amended with regard to dredging or surveying in traffic separation schemes. 1987: In 1987 amendments were made to several rules, including rule 1(e) for vessels of special construction; rule 3(h), vessels constrained by her

draught and Rule 10(c), crossing traffic lanes. 1989: In 1989 Rule 10 was altered to stop unnecessary use of the inshore traffic zones associated with TSS. 1993: In 1993 amendments were made concerning the positioning of lights on vessels.

2001: In 2001 new rules were added relating to wing-in-ground-effect (WIG) craft 2007: In 2007 the text of Annex IV (Distress signals) was rewritten

Purpose of this write-up There are many implied and expressed terms in RoR. A good understanding of RoR is possible only when a learner comprehends those terms clearly. We have mainly emphasized on the explanation of criticality of rules and some words which are usually misunderstood by a learner. Learning the rules by heart has an advantage of getting them at finger tips but one should aim for understanding them thoroughly to be able to take correct decisions whenever a risk of collision exists or deemed necessary. We shall also discuss about some situations and their correct actions to corelate them with usual Oral Questions. Reference & Publications RoR have connections with IMO, Section A-VIII/2 of the STCW Code, SOLAS’74, International Code of Signals, IAMSAR, IMO Ship’s Routing Guide and GMDSS Regulations. Absolute ‘Right of Way’ A commonly held misconception concerning the rules of marine navigation is that by following specific rules, a vessel can gain certain rights of way over other vessels. No vessel ever has absolute "Right of Way" over other vessels. Rather, there can be a "Give Way" (burdened) vessel and a "Stand on" (privileged) vessel, or there may be two give way vessels with no stand on vessel. A stand on vessel does not have an absolute right of way over any give way vessel, for if there is a risk of collision, a stand on vessel may still be obliged under Rule 2 to give way so as to avoid it, if doing so will be effective and is practicable. Two power-driven vessels approaching each other head to head are both deemed to be "Give Way" and both are required to alter course so as to avoid colliding with the other. Neither vessel has "Right of Way". Expressed and Implied Terms Expressed Terms: These terms are defined in Rule 3. Implied Terms: There are many implied terms in RoR. The definitions of those

words have not been stipulated in RoR. However, if we try to understand them thoroughly, we can clearly comprehend their meanings. We have discussed about them in appropriate paragraphs.

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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. Inland Waters: Inland waters that are not connected with high seas may be regulated by ‘Rules for Inland Waters’ derived by government of a particular state or country. As an example in Bangladesh, RoR apply in the navigable waters of ‘Karnaphuli River’ but not in other rivers that are connected to it but are neither not connected with high seas nor navigable by seagoing vessels. (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. Roadsteads: A sheltered area outside a harbour where a ship can lie safe at anchor, also known as a roads. Harbour: A harbor or harbour, or haven, is a place where ships may shelter from the weather or are stored. Harbours can be man-made or natural. Special Rules: They are made by a particular state or government. Usually, they are made in close conformance with RoR. (c) Nothing in these Rules shall interfere with the operation of any 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 or 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 authorized elsewhere under these Rules. Three types of vessels: Warships, Vessels proceeding under convoy and a fishing fleet engaged in fishing. Degree of Special Rules: These rules are usually more stringent than RoR. Additional Station: It may be an additional mast fitted with signal lights and/or shapes.

Fishing vessels engaged in fishing as a fleet: These are different from the vessels mentioned in Annex-II and Rule-26(d): A vessel engaged in fishing in close proximity to other vessels engaged in fishing. (d) Traffic separation schemes may be adopted by the Organization for the purpose of these Rules. The Organization: This is the International Maritime Organization (IMO), a body of the United Nations. Rule 1(d) authorizes IMO to adopt traffic separation schemes to which Rule 10 will apply. The details of TSS can be found in “IMO Ships’ Routeing Guide’’. TSS: As defined by IMO Ships’ Routeing Guide, ‘A routeing measure aimed at the separation of opposing streams of traffic by appropriate means and by the establishment of traffic lanes’. (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-signaling 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-signaling appliances, as her Government shall have determined to be the closest possible compliance with these Rules in respect of that vessel. Deviation from Lights & Shapes: Some specially constructed vessels’ unique functions may be impaired if these rules are complied with fully. In those cases, Rule 1(e) permits a deviation from the navigation light, shape, or sound-signal requirements but only to the point of preventing interference with the special function. Special Vessels’ Lights: Information about lights and shapes of special vessels such as Warships, Aircraft Carriers and Submarines can be found in Mariners’ Handbook, Annual Summary of Notices to Mariners and Sailing Directions.

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 the neglect of any precaution which may be required by the ordinary practice of seaman, or by the special circumstances of the case. Exonerate: Does not relieve Neglect to comply with these Rules: A vessel does not display appropriate lights and shapes required by RoR. Neglect to comply with any precaution: These precautions may be required by good seamanship or special circumstances. The Rules are written for usual or likely situations; atypical situations are termed "special circumstances." A complete list of special circumstances is, of course, impossible to provide. A number of examples should give some idea of the term's meaning. Vessels proceeding stern-first are considered to be in special circumstances A vessel is expected to keep clear of an anchored vessel or a vessel not under command Vessels not making way may be in special circumstances. First, a vessel should avoid stopping in a high-traffic area, and when a vessel decides to stop, it should make its intentions clear to other vessels in the area. As always, a proper lookout should be maintained. A drifting vessel should not expect that other vessels will keep clear of her unless she displays proper lights and shapes for a vessel NUC. If a vessel is drifting, its course may not be obvious. If the stopped vessel is large, it may not be able to move out of the way of a fast oncoming vessel. Whatever the "if" of the situation, encounters with vessels not making way through the water deserve extra caution. A vessel must not proceed in dense fog if her radars are not functional, rather she should stay at anchorage till her radars are repaired or fog disperses. Another special circumstance occurs when two vessels have managed to get themselves much too close to each other and are headed in unfortunate directions. Collisions about to happen are often called "extremis" situations. The vessels involved are said to be "in extremis."

When two vessels approach one another at a difficult bend in a tidal river it’s a good practice that the one having the tide against her to wait until the other has passed. This is because a vessel against the tide has better maneuverability and can hang out for sometimes with

controlled engine movements or she can even drop her anchor for the interest of avoiding collision. An extremis (imminent danger situation) situation occurs when a collision can be avoided only by the action of both vessels. Here Rule 17(b) requires the stand-on vessel to maneuver to avoid the collision. In shallow waters, a vessel is likely to experience Squat and Interaction. Squat causes bodily sinkage to a vessel and change of trim which consequently causing reduction of speed and/or grounding. Interaction can cause bow cushon or bank suction or smelling the ground, consequently causing grounding, collision, turbulence to other vessels at berth, etc. To avoid all these dangers, the good seamanship is to reduce speed and proceed with caution. In an extremis situation, the operators on one or both of the vessels have failed to take the first line of preventive actions prescribed by the Rules. The second line of defense comes into play; the parties in extremis situation are required to do whatever is necessary to avoid a collision or at least to minimize the damage. The physical limitations of the vessels may also impose special circumstances. Draft limitations will prevent some give-way vessels from turning into shallow water; a sluggish craft may preclude a timely maneuver for others. (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. Construe: It means explain. Dangers of navigation: A vessel is unable to alter her course due to the presence of shallow water although she is required to do so in compliance with some rules (Rule-14, 15 etc.). Dangers of Collision: On a head-on situation, a vessel is unable to alter her course to starboard due to the presence of another vessel on her starboard side. This way she is unable to comply with Rule-14. Special Circumstances & Immediate danger: Mentioned below. A departure is only permitted when there are special circumstances and there is immediate danger. The departure must be of such a nature as to avoid the danger which threatens.

Embarking and disembarking pilots could be considered as special circumstances since maneuvering of both vessels may expose both the pilot vessel and the pilot to danger. Limitation of a vessel: Vessel in a convoy may have limitations to alter course in a crossing situation. Action taken in accordance with the advice to avoid a squadron or convoy on the port bow would not be a departure from the Rules if executed at long range before risk of collision begins to apply Departure from these rules: Rule 2 is an overriding rule, often called the "Rule of Good Seamanship". Strict literal compliance with the Rules may not be a defense if a collision occurs. Rule 2 holds the mariner responsible not only for complying with the Rules but also for avoiding collisions. Merely complying with the Rules is not enough. If, in fact, strict compliance with the Rules would result in immediate danger, a departure from the Rules (to the extent necessary to avoid the danger) is required. A mariner who chooses to adhere strictly to the word of the Rules, and thereby causes or fails to avoid a collision that could have been prevented by other action, may not use compliance with the Rules as a defense to liability. A departure is under Rule-2(b) is justified only if necessary to avoid immediate danger. Both necessity and immediate danger must be present. Your responsibility is not only to follow the COLREGs – you are also responsible for doing everything necessary to avoid the risk of collision and the dangers of navigation.

Rule-3: General Definitions (a)The word ‘vessel’ includes every description of water craft, including nondisplacement craft, WIG craft and seaplanes, used or capable of being used as a means of transportation on water. Vessels: All vehicles that operate on the water are vessels, including displacement craft (those that "float" or are supported by the static buoyancy derived from the water that their hulls displace) Non-displacement crafts: These are supported by the dynamic lift of hydrofoils or other lifting surfaces. Seaplanes: A seaplane is a powered fixed-wing aircraft capable of taking off and landing (alighting) on water.

"Used or capable of being used as a means of transportation": This phrase implies the practical transportation of people or cargo. Inner tubes are not included, although sailboards are. “WIG craft”: A Wig Craft is a multimodal craft which, in its main operational mode, flies by using ground effect above the water or some other surface, without constant contact with such a surface and supported in the air, mainly, by an aerodynamic lift generated on a wing (wings), hull, or their parts, which are intended to utilize the ground effect action. (b) The term ‘power-driven vessel’ means any vessel propelled by machinery. Propelled by machinery: Vessels propelled by oars, paddles are not included in this definition. Vessels propelled by machinery as well as any other means of propulsion are considered to be power-driven vessels. A day shape is required for most vessels using both sails and machinery for propulsion; see Rule 25(e). (c) The term ‘sailing vessel’ means any vessel under sail provided that propelling machinery, if fitted, is not being used. Propelling Machinery: Operation of the engine to generate electricity or to heat water, does not make the sailing vessel a power-driven vessel, so long as the propeller (or paddle wheel) is not engaged. (d) The term ‘vessel engaged in fishing’ means any vessel fishing with nets, lines, trawls or other fishing apparatus which restrict maneuverability, but does not include a vessel fishing with trolling lines or other fishing apparatus which do not restrict maneuverability. A fishing vessel: This is a vessel used for catching fish, whales, seals, walrus or other living resources of the sea.( (SOLAS I/2)). If a fishing vessel is not engaged in fishing she should display lights and shapes as per Rule-26(e). Restrict maneuverability: Not all fishing gears restrict maneuverability. Study Mariner’s Handbook for the details of pictorial fishing gears used by vessels engaged in fishing. Lines: The term ‘lines’ refers to lines such as long-lines which may be miles long and to which are attached at regular intervals many leaders and hooks. Trawls: The term ‘trawls’ refers to large open-mouthed nets that are towed through the water by one or two specially equipped fishing vessels

(trawlers). Vessels fishing with trolling lines: (for example, a sport fisherman's rod and reel with the line towed astern), which do not restrict maneuverability.

Other rules: Rule-26 prescribes the lights and shapes and Rule-18 prescribes the privilege and obligations for vessels engaged in fishing (e) The word ‘seaplane’ includes any aircraft designed to maneuver on the water. When on the water a seaplane is a vessel. Rule 31 gives the navigation light and shape requirements for seaplanes. Non-displacement crafts are not to be considered as seaplanes for the purpose of Rule 18(e). (f) The term ‘vessel not under command’ means a vessel which through some exceptional circumstance is unable to maneuver as required by these Rules and is therefore unable to keep out of the way of another vessel. Examples: Vessel with anchor down but not holding Vessel riding on anchor chains Vessel with inoperative steering gear Sailing vessel becalmed Exceptionally bad weather (relative to vessel claiming status) Rule 18 assigns the privileges and obligations & Rule 27 prescribes the lights and shapes for not-under-command vessels. A NUC vessel is entitled to get privileges only when she displays required lights and shapes. (g) The term ‘vessel restricted in her ability to maneuver’ means a vessel which from the nature of her work is restricted in her ability to maneuver as required by these Rules and is therefore unable to keep out of the way of another vessel. The term ‘vessel restricted in her ability to maneuver’ shall include but not be limited to: Because of the nature of her work: The status does not apply to vessels that cannot maneuver because of external reasons such as - they are in a narrow channel or in shallow water or because of strong currents or bad weather. Vessels restricted in ability to maneuver may or may not be underway. These vessels are often called as RAM vessels. Distinction: The vessels mentioned below (i - vi) must be engaged in their special operations to be entitled to the status as a vessel restricted in her ability to maneuver.

(i) a vessel engaged in laying, servicing or picking up a navigation mark, submarine cable or pipeline; No Explanation written a vessel engaged in dredging, surveying or underwater operations; No Explanation written a vessel engaged in replenishment or transferring persons, provisions or cargo while underway; No Explanation written (iv) a vessel engaged in the launching or recovery of aircraft; No Explanation written a vessel engaged in mine clearance operations; No Explanation written 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. Severely restricts: A vessel engaged in a routine towing operation is not normally justified as restricted-in-ability-to-maneuver status. This is emphasized in the definition by the words "severely restricts." (h) The term ‘vessel constrained by her draught’ means a power-driven vessel which because of her draught in relation to the available depth and width of navigable water is severely restricted in her ability to deviate from the course she is following. CBD Vessels: These vessels are specified to be only power-driven vessels. CBD vessels don’t necessarily mean VLCCs, ULCCs, Larger ships, Deep Draft Vessels. Even a small power driven vessel can be entitled to be a CBD vessel when her draft in relation to available depth and width of surrounding navigable waters makes her restricted to deviate from her present course. Available depth & width of navigable water: The depth of water directly underneath the vessel is not the determining factor; rather, the depth close to either side of the vessel determines the level of constraint.

(i) The word ‘underway’ means that a vessel is not at anchor, or made fast to the shore, or aground. Underway: Apart from the definition above, a vessel that is "underway" need not be moving through the water. Making way through the water (used in Rules 26, 27, and 35): If a vessel underway is moving relative to the water, it is making way. For example, if a ship is headed up a river, making five knots through the water, and there is a five-knot current against it, then it is making way through the water even though it is making no progress relative to the shore. Making no way through the water (used in Rule 35): If a vessel is making no way through the water, it is stopped and drifting. A vessel is drifting down the river is not making way, even though it is moving much faster over the bottom At Anchor: Usually a vessel is considered at anchor only when she is holding the chain and brought up. A vessel is considered underway when she is dragging her anchor or if she is not yet brought up to anchor she has let go. (j)The words ‘length’ and ‘breadth’ of a vessel mean her length overall and greatest breadth. Length: Here in this rule, Length means LOA but not LBP or Waterline Length. LOA: The maximum length of a vessel 's hull measured parallel to the waterline, usually measured on the hull alone, and including overhanging ends that extend beyond the main bow and main stern perpendicular members. LBP: Measured from the point the stem intersects the design waterline and the centerline of the rudderpost Waterline Length: Measure between points where stem and stern enter the water. Breadth: The greatest breadth does not always occur amidships. (k) Vessels shall be deemed to be in sight of one another only when one can be observed visually from the other. These eight rules do not apply to two vessels not "in sight of one another." Even though the vessels may know each other's exact course, speed, and position by means of Automatic Identification System (AIS) or Automated

Radar Plotting Aids (ARPA) or other devices, Rules 11 through 18 apply only if visual contact is also made.

(l)The term ‘restricted visibility’ means any condition in which visibility is restricted by fog, mist, falling snow, heavy rainstorms, sandstorms or any other similar causes. Connections: Rules 19 and 35 apply only to vessels in or near an area of restricted visibility. Other similar causes: Such as smoke from own vessel, other vessels, or ashore, and dust storms, smog (a kind of air pollution, originally named for the mixture of smoke and fog in the air) etc. (m) The term ‘wing-in-ground (WIG) craft’ means a multimodal craft which, in its main operational mode, flies in close proximity to the surface by utilizing surface-effect action. WIG crafts are not to be considered as seaplanes or non-displacement craft. The definition for "Wing-In-Ground" craft was added to address hybrid water/air craft that can operate on the water and just above the water in ground effect -- on a cushion of air.

Part B - Steering and Sailing Rules Section I - Conduct of Vessels in any Condition of Visibility Rule-4: Application Rules in this section apply to any condition of visibility. Rule 4 tells us that vessels operating under any and all conditions of visibility are required to follow Rules 5 through 10. In other words, these Rules apply all of the time. 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. STCW’95: Mandatory standards regarding watch keeping, including standards for keeping a proper look-out, are contained in Part A, Chapter VIII of the STCW Code. Lookout: The term, as used by the Rules, denotes not a person but rather the systematic collection of information. Responsibility for maintaining a proper lookout lies with the vessel's

operator, not with a subordinate designated as "lookout." The vessel's operator--that is, Master, Watch Officer, or Person in Charge--is the lookout manager. Sometimes, it’s stressed that a lookout man should be stationed forward if weather is good in order to ensure no-destructions to him. But this is also true that a lookout man stationed forward may not perform his duties properly due to lack of diligence. Purpose of Lookout: The purpose of the lookout is to collect the information needed to avoid collisions. Duty of the Lookout: Traditionally, the duty of the lookout was to watch out for vessels, lights, and other objects (such as reefs, shoals, and icebergs) by sight and hearing alone and to report their presence to the vessel's operator promptly. The lookout was allowed some discretion on what to report in crowded waters and would be assigned no other duties that would interfere with this important function. Today, a proper lookout is a team effort. It is the Master's duty to ensure that a proper lookout is maintained at all times. That duty cannot be delegated. When a lookout man is stationed forward, he must use his discretion and report the lights or objects which are likely to bring risk of collision, especially small craft which may not have been observed from the bridge. Interference on Sight & Hearing: Good eyesight is affected by environmental factors such as ambient light, weather conditions, water spray, or wind. Fatigue can also affect vision, as can moving between extremes of light. Similarly, hearing may also be impaired. The noise of wind and wave and ship's machinery may mask the sound you want to hear. The blast from a ship's own whistle blocks out other noises and will temporarily, perhaps permanently, reduce the hearing of the lookout. Hearing testing would be advised. All Times: The duty to keep a proper look-out applies also when a vessel is at anchor, especially if there is a strong tide running, or if other vessels are likely to be passing by. Proper and appropriate: These are vague terms. This rule doesn’t provide a precise guidance on adequacy of the lookout. However, STCW Code gives us a detailed guideline on determining the strength of lookout. Proper Look-out: A proper lookout is that which is sufficient to prevent a

collision, without any allowance for good luck, in the prevailing circumstances and conditions

By Sight & Hearing and all available means: Sight, hearing, and "all available means" are tools of the lookout. Some of the available means are Binoculars, Radar (including long range scanning), VHF, Bridge-to-Bridge radiotelephone, Automated radar plotting aids, Differential GPS (DGPS), Satellite Navigation Equipment, Automatic Identification Systems (AIS), radio transponders, Vessel traffic services, Navigation and piloting instruments, sound receivers to receive fog signals etc. Prevailing Circumstances & Conditions: Some examples are:A lookout in the open ocean can be less intense than one in coastal or inland waters. It cannot, however, be abandoned—mid-ocean collisions do occur. A lookout on a vessel at anchor is required, with the level of effort depending upon the location of the anchorage, depth of water, type of ground tackle, wind, currents, waves, and so forth. The lookout should determine whether the anchor is dragging and should warn other vessels of the anchored vessel's presence. The means and methods for maintaining a lookout vary with night and day. At night, lookouts should make greater use of binoculars and radar. Masters should post observers away from the vessel's own lights so as not to impair the night vision of the lookout. During the day and in good visibility, a vessel can be seen at a much greater distance, as indicated by the fact that a masthead light for the largest vessel need be visible for only six miles and for the smallest vessel, only two miles. During daylight, and under the most favorable conditions, the watch officer on a large vessel may perform the lookout alone. The size and arrangement of a vessel have a direct bearing on the efforts required to maintain a proper lookout. On small vessels where there is an unobstructed all-around view and where there is no impairment of night vision, the craft's operator may both steer and keep the lookout. Unobstructed view, simple controls, no distractions, and high maneuverability are important here. Visibility is generally the key factor in maintaining a proper lookout. As the visibility decreases, the level of effort to maintain a proper lookout increases tremendously. Sight needs to be augmented by hearing, radar, and radiotelephone. Unless you are in the open ocean, you should seek precise navigational information. In the case of low-lying fog, at least one person should be positioned high enough to see over the fog. Full appraisal of the situation: It is this broad objective that you should keep

in mind when managing the lookout. If there is not enough information to assess the situation, you should tap all your resources to gather more. If you are still unable to acquire the information you need, then you should take steps immediately to reduce your requirement for information--for

example, by slowing or stopping. Otherwise, you are violating Rule 5. This is not one of those circumstances where doing more with less is a virtue. A lookout man should be always aware of what is happening on his own vessel keeping a check that all navigational equipment required for keeping the vessel on course are functioning correctly.

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. In determining a safe speed the following factors shall be among those taken into account: Safe Speed: The word ‘safe’ is intended to be used in a relative sense. A speed could reasonably be considered safe in the particular circumstances. Every vessel shall at all times: This rule applies in all conditions of visibility to all vessels. The Officer of the watch should not hesitate to use the engines in case of need. However, timely notice of intended variations of engine speed should be given when possible. Proper and effective action: The first objective of maintaining a safe speed is to permit the vessel "to take proper and effective action to avoid collision”. To be able to maneuver as prescribed by the Rules, the vessel must be moving slowly enough to control its forward motion. In some cases, it must also be moving fast enough for the rudder to effect a turn promptly. To avoid hydrodynamic effects in shallow waters, vessel operators are expected to be familiar with these effects and to reduce their speed sufficiently to maintain positive rudder control. Stopping Distance: The second objective of requiring a safe speed is to enable the vessel to be stopped "within a distance appropriate to the prevailing circumstances and conditions”. In most cases where the risk of collision exists, a course change will be the most common action. However, if maneuvering room is limited or if visibility is poor, stopping the vessel (perhaps in conjunction with a turn) could be the best way to avoid or minimize damage. Other rules: Rule 8 requires vessels to slow or stop to avoid collision or to give more time to assess the situation. Rule 19 requires that vessels in areas of restricted visibility encountering vessels forward slow to the bare

minimum needed for steering, or stop altogether.

Factors to consider: Most of Rule 6 presents factors that must be considered in determining safe speed. These factors are not necessarily listed in order of importance, and the list is not exhaustive. (a) By all vessels: The state of visibility; Note: Refer Rule-19.

The traffic density including concentrations of fishing vessels or any other vessels; Note: Traffic density is important because the probability of a collision increases with the density (iii) The maneuverability of the vessel with special reference to stopping distance and turning ability in the prevailing conditions; Note: Stopping distances will vary substantially depending on whether the vessel is turning or proceeding in a straight line. The maneuvering characteristics of most of the larger vessels are required to be posted on the bridge. Operators should learn the characteristics before the information is needed. The distance that a vessel will cover in a crash stop before being brought to rest from full speed is likely to be between 5 and 15 ship lengths, depending upon speed, displacement, type of machinery, maneuverability of the vessel, Type of engines (steam, diesel, turbine, etc), Power of the engine, Stopping distance, Turning circle, Fast or slow vessel, Maneuverability with regard to Condition of loading, Draught, Trim, Etc. (iv) At night, the presence of background light such as from shore lights or from back scatter of her own lights; Note: Background lights and backscatter decrease the effectiveness of a lookout by sight and therefore require a proportional decrease in speed. A small vessel has a particular problem because the vessel's own lights are close to the operator. Careful design of the navigation light arrangement will minimize backscatter and reflection from the vessel itself. The state of wind, sea and current, and the proximity of navigational hazards; Note: The need to reduce speed in the face of mounting adversity The draft in relation to the available depth of water.

Note: Draft restrictions relate to speed in several ways. If there is little under keel clearance, it is likely that shallower water is nearby. It is easier to avoid running aground from a low speed, and if a grounding cannot be avoided, the damage will be less. If a vessel's draft exceeds the depth outside a channel, the vessel will be limited to straight-line stopping within the channel, which is less effective than a combination of slowing or reversing engines and turning away. Hence a lower speed is usually required. In shallower waters, a vessel's speed introduces hydrodynamic forces that are not present in deeper waters. The effect on the vessel is called "squat," and it increases as the underkeel clearance decreases and as the vessel's speed increases. The hydrodynamic effect of high speed through a channel may cause a vessel to be pulled toward or into the bank or may pull two vessels passing close together off course. (b) Additionally, by vessels with operational radar: Note: The term ‘operational radar’ means radar in use. In open waters a ship using radar may proceed at a relatively higher speed, provided the speed is adjusted appropriately upon detection of another vessel. Radar equipment varies greatly in power, sophistication, antenna installation, and so forth. The mariners need to understand these qualities and limitations thoroughly. (i) The characteristics, efficiency and limitations of the radar equipment; Characteristics: Radar may fail to detect small targets, alterations of course made by other vessels are usually less apparent and the use of radar bearings is more likely to result in a faulty appreciation of risk of collision than visual bearings taken by compass. Efficiency: The efficiency of the equipment for the purpose of detecting the presence of other vessels and determining whether risk of collision exists must also be related to the competence of those observing it and the way it is being used. Range performance, Minimum range, Diameter of PPI, Scale of display, Plotting facilities, Range accuracy, Heading indicator, Bearing accuracy, Azimuth stabilization. Limitations: Because of their lower power and higher pulse repetition rate, these navigation radars--also called three centimeter (3 cm), X-band, and high frequency radars--have a limited range. A vessel's course might be changed regularly to ensure that any vessel in a blind arc, which may be caused by a vessel's masts or other structures, could

be detected early. (ii) Any constraints imposed by the radar range scale in use;

Short range scales give good resolution and enable the detection of small targets; long range scales sacrifice detail to gain early detection. To the extent that different range scales are not available, speed should be reduced. Constraints may be imposed by every range scale that can be used. When using the longer range scales definition and discrimination are reduced and small targets are less likely to be detected, whereas shorter range scales do not permit early detection of targets and do not enable the observer to obtain an overall assessment when several vessels are in the vicinity. The range scale which is most suitable for the locality should be selected but the scale should be changed at regular intervals. The scale should not be changed when there is a dangerous target at close range. When two radar displays are available and in use it may be advantageous to select a different range scale on each display to avoid the necessity of switching scales. (iii) The effect on radar detection of the sea state, weather and other sources of interference; Vessel’s speed should be reduced when interference (caused by large waves, heavy rain or snow, or the like) impairs the performance of the radar. Interference: The effect of rain clutter is much less when using l0 cm wavelength than when using 3 cm. This is often also the case with clutter caused by sea return. Vessels fitted with two radars, one of each wavelength, would be expected to make use of the 10 cm wavelength for detecting other vessels in conditions likely to cause severe clutter, particularly in heavy tropical rain squalls. (iv) The possibility that small vessels, ice and other floating objects may not be detected by radar at an adequate range; The location of the vessel and the season of the year are important in judging whether undetected vessels or ice may be present. (v) The number, location and movement of vessels detected by radar; Accurate radar plotting becomes more difficult as the number of vessels increases. Automated radar plotting aids make the task easier. The greater the number of targets indicated on the radar display the more difficult it may be to determine risk of collision and to assess the effect of possible maneuvers, although some radar systems are capable of providing information of this kind. (vi) The more exact assessment of the visibility that may be possible when

radar is used to determine the range of vessels or other objects in the vicinity.

The observed radar range of a vessel can be correlated to visibility by noting when the vessel can first be sighted. At night, when the vessel's lights can first be seen, the radar range of the vessel equates the visibility (assuming that the visibility is not so good that masthead light intensity becomes the controlling factor. When fog or mist is considered likely to develop, the radar should be in operation. It may be possible to determine the extent of the visibility by observing the radar ranges at which other vessels or navigation marks are first visually sighted, or at which they disappear from view. At night the probable presence of fog may be indicated by failure to see the lights of a vessel which gives a strong echo within the normal visual range. 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. The existence of risk of collision is implicit to the operation of other rules such as Rule 13 (Overtaking), Rule 16 (Action by Give-way Vessel), Rule 17 (Action by Stand-in Vessel), and Rule 18 (Responsibilities between Vessels). Risk of collision in Head-on situation: The relative bearings of two vessels affect the degree of risk. Two vessels meeting on near-reciprocal courses would close relatively rapidly, because their closing speed would be the sum of the two speeds. The risk of collision would arise while they were still relatively far apart. Risk of collision in Overtaking situation: Where one vessel is overtaking another on nearly the same course, the closing speed would be the difference between the individual speeds. Unless one is traveling a great deal faster than the other, it would take a long time for the overtaking vessel to draw abeam of the other. In the overtaking situation, the vessels would be relatively close together before risk of collision arose. Risk of collision in Crossing situation: Crossing situations would be somewhere between meeting and overtaking. Avoid Development of Risk of Collision: Either vessel is, of course, free to act before risk of collision exists in order to avoid it altogether. If RoC with another vessel doesn’t exist, then there is no necessity to take action as a give way vessel. Doubt: If there is any doubt or the information at hand is not accurate or

complete, then risk of collision shall be deemed to exist. In case of doubt, the OOW must call Master immediately as per STCW Code, Ch-VIII. It’s understood that doubt begins when an OOW starts to feel

confusion about a situation and feels whether he should call Master or not. Beyond this point, the OOW’s delay in calling Master could be considered as negligence and at times, calling Master late might result in a critical situation when Master may not have many options on hand to avoid a close quarter’s situation or collision. All available means: Examples are Look out Compass repeaters Binoculars Sound / light signaling equipment Radars / ARPAs The radiotelephone may be used to advantage in certain circumstances for the purpose of clarifying a situation involving two vessels and indicating intentions via well regulated VTIS. However, collision avoiding actions shall not be taken basis VHF agreement between two vessels since it’s never guaranteed that the second vessel is the vessel that you’re trying to communicate with as many vessels make funs out of it. Valuable time may be wasted in attempting to make radio contact instead of concentrating on the assessment of collision risk and the need for action. Reference is also made to the further danger of proposing, by VHF radio, to take action which is not in compliance with the Collision Regulations. In RoR, there is no mention about the use of RT to determine RoC, rather appropriate sound signals are prescribed for the same. As AIS can be used to advantage for collision avoidance, such as in determining the identity of another vessel and in more rapid detection of changes of heading, vessels may be expected to make use of the equipment in appropriate circumstances. The AIS target data (CPA, TCPA etc.) MUST not be taken as correct as it is found accurately only in ARPA/Radars. An OOW should acquire the targets on Radar/ARPA using Radar functions instead of just simply clicking the AIS Symbol of a target echo on radar screen to get CPA, TCPA, etc.

Appropriate to the prevailing circumstances: The use of the available means

to determine risk of collision depends on the prevailing circumstances and conditions, such as daytime or night time, low traffic or heavy traffic, coastal waters or ocean waters, clear visibility or restricted visibility, etc.

(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. Proper use of Radar Equipment: Rules 6, 7, 8 and 19 contain specific references to the use of radar and there is an important implied reference in Rule 5. Proper use of radar may include optimum setting of all controls, appropriate range scale & display, etc. The value of radar in assessing risk of collision in poor visibility is obvious. Rule 19 (Conduct of Vessels in Restricted Visibility) requires that a vessel in restricted visibility determine whether risk of collision exists when it detects by radar alone the presence of another vessel. But radar is also valuable in clear weather after a target has been sighted visually, being better able than the human eye to measure range and other distances. Long range scanning: In any kind of weather, long range scanning is a very useful tool to an OOW. If a target is detected at long range, an OOW can do little alteration of course / speed to avoid a RoC. However, RoC in a head-on situation remains the same even at long range. If two high-speed vessels meet head-on, their relative speed becomes very high and TCPA reduces significantly, therefore an OOW gets less time to takes actions. But if the situation is detected at long range, the OOW gets sufficient time to take early action. That’s why the OOW should cultivate a habit of doing long range scanning of targets frequently in his/her watch. True Motion Display: The OOW must select the radar display better suited to the operating conditions. In general, true-motion (sea- or ground-stabilized) radars are preferred for navigation and piloting in confined waters as the position of the observer’s own ship moves in accordance with its own path. An alteration of course made by another vessel moving at fairly high speed is likely to be more readily apparent on the true motion display from the change in direction of the echo trail. True motion is generally more suitable for use with the lower range scales in congested waters rather than in the open sea. Relative Motion Display: Relative-motion displays allow the observer to assess more quickly the movement of other vessels in relation to his or her own movement. All but the smallest vessels are required to have radars stabilized in azimuth (that is, in the horizontal plane). Radars without compass stabilization are almost useless for determining the actions of other vessels. Radar Plotting: It is not enough to just look at the radar. Plotting is usually

appropriate in relatively open waters.

True & Relative Radar Plotting: The principles of relative plotting should be understood by all observers, as this is the method which enables the closest position of approach to be determined. The true plot is simpler to understand, and is considered by many to be superior when there are several targets on the screen. Alterations of course, or speed, by the observed vessel, carried out simultaneously with, or shortly after, an alteration by own vessel, are likely to be more readily detected by a true plot than by a relative plot. Use of Vectors: The use of vector is very common. You can use this function for multiple targets on the radar screen. Usually, the user selects relative vector to see how a target will pass her own ship actually. Alteration of course and speed, however, don’t get updated in vector immediately, it takes sometimes. A prudent user sometimes changes the vector setting from relative to true to see a target’s actual course and thus it helps to find target’s aspect. The use of appropriate vector length is also very important. Longer vector-length of numerous targets on the radar screen lead to an unnecessary clutter and confusion to the OOW. Equivalent Systematic Observations: Plotting is not required if "equivalent systematic observation" is used. These other observation techniques include manual and automatic (computerized) radar plotting aids or the listing of bearing, range, and time at regular intervals. Plotting by the vessel's operator in congested waters may take so much time that it becomes counterproductive. In such cases automated radar plotting aids are especially appropriate.

(c) Assumptions shall not be made on the basis of scanty information, especially scanty radar information. Assumption & Scanty Information: The word ‘Scanty’ stands for ‘Insufficient’. Assumptions made on the basis of scanty information have been a contributory cause of many collisions in both clear and restricted visibility. Rule 7 warns mariners against relying on radar for more information than it can realistically give. The mariner who assumes an approaching vessel will pass well clear after making a couple of long-range radar observation is inviting danger and violating Rule 7. Distances magnify small errors, and errors are almost inevitable because of the imprecision of observations made from a moving vessel. Nor can you

assume that the other vessel is maintaining a constant course and speed. Regular and consistent checking of observations is imperative.

Several observations should be taken at short and regular intervals to reduce the effects of these random errors when there is a possibility of a close quarter’s situation developing. Bearings taken relative to the ship’s structure can be very misleading in determining whether risk of collision exists. (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; The closest distance of approach is perhaps the prime element in the risk of collision situation. A collision occurs when the distance of closest approach goes to zero. Sighting an approaching vessel against components of the ship's structure may give a rough indication of whether there is risk of collision and may provide sufficient basis for deciding whether to make a bold alteration to pass astern of a vessel being overtaken or crossing from the starboard side. A number of factors are involved in such an assessment: Closest distance of approach Type of waterway - The type of waterway plays a part in the calculation of risk. On the open ocean the distance of closest approach triggering risk of collision is greater than in confined waters because on the ocean it is easier to keep well clear. Vessel size and maneuverability - Vessel size and maneuverability have a substantial impact on risk of collision. A small vessel that can stop or turn in its own length has a much smaller zone of risk than a large vessel that may need a mile or more to stop and only begins to turn after the rudder is put over. Speed - Speed expands the zone in which risk of collision exists. Higher speeds give the mariner less time to refine the accuracy of vessel path predictions (remember Rule 6). Distance out from closest point of approach Relative bearings Appreciably change of bearing: Here bearing means true bearing but not relative bearing. Due to appreciable change of bearing, the change in target data and aspects will become evident, such as a noticeable change in CPA,

TCPA, BCR, etc. However, an appreciable change of bearing at greater ranges does not necessarily mean that there is no risk of collision. The other vessel may be making a series of small alterations which have not been observed.

(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. Large vessel or tow: Even if the compass bearings between two vessels do change, there may still be the potential for collision. A tow has two components – the towing vessel and the vessel being towed. If a RoC doesn’t exist with the towing vessel, it may exist with her tow. The same explanation goes for a large vessel – bearings between bow and stern differ significantly. Mariners must consider the length of an approaching vessel before determining that a RoC doesn’t exist with the other vessel’s bow and stern or with the towed vessel and her tow. Risk associated with changing bearing at close range: An appreciable change of bearing at close ranges does not necessarily mean that there is no risk of collision. An appreciable change of bearing at short range may be associated with a dangerously close passing distance. The rate of change of bearing increases as two vessels pass too close to each other. Such a passing distance will bring danger of collision. If an overtaking vessel with greater speed, approaching from starboard quarter of a vessel being overtaken with lower speed, suddenly starts crossing the bow of the vessel being overtaken assuming that the overtaking vessel can execute this action safely, a collision may happen if overtaking vessel’s steering or M/E fails at that point due to the fact that both vessels are at close range. Also, at close range in confined waters, the effect of interaction between two vessels is significant and a collision is always possible. Rule-8: Action to Avoid Collision (a) Any action to avoid collision shall be taken in accordance with the rules of this Part and, if the circumstances of the case admit, be positive, made in ample time and with due regard to the observance of good seamanship. This rule tells how the avoiding action must be executed, not which vessels are required to take the avoiding action. Shall, if the circumstances of the case admit: ‘Shall’ is a mandatory word. ‘Shall’ is used to emphasize the need for positive action to be taken in ample time. ‘If the circumstances of the case admit’ is an escape clause though.

Positive, made in ample time, with due regard to the observance of good seamanship: These are indefinite terms. Positive: Positive action is a significant change in vessel’s course and/or speed. A large alteration of course or speed to avoid a collision indicates that the intention of the action is positive. A vessel’s positive action becomes easily evident to others observing her. Ample Time: In this rule, action shall be taken in ample time means that an action shall be taken in a time so that a collision can be avoided. This paragraph didn’t say action is to be taken in ample time to avoid a close quarter’s situation. If we compare ample time and good time, we can say that ample time is meant for avoiding a collision and good time is meant for avoiding a close quarter’s situation. So, as per RoR, good time occurs much earlier than ample time. Good observance of Seamanship: Some examples of good seamanship have been mentioned in discussions for Rule-2. Do not take an action which makes the situation worse for any other ship in the vicinity; assess what they may have to do. (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. Let the other vessel know what you are doing. Make it obvious by sight in good visibility and obvious on the radar screen in areas of restricted visibility. Give the proper maneuvering signals if operating under the International Rules. (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. Alteration of Course Alone: Two variables can be altered to avoid collisions: Course and Speed. On larger vessels, change of speed may take a considerably long time, especially when the engines are not ready for maneuvering but you need to change speed immediately. That’s why, this paragraph allows for a course change alone, which can be made directly and immediately from the bridge. Alterations of speed take longer to put into effect than alterations of course so they are less likely to be readily observed by other vessels

Close-quarters situations: There is no definition of Close-quarters situations. But generally we can suppose that it’s a situation between two vessels when action taken by one vessel may not be sufficient to avoid the collision. In rivers, harbors, and other inland waterways; close-quarters situations are unavoidable. The term close-quarters situation has been implied in Rule7(CPA distance which helps assess a risk of collision), Rule-8d (safe distance the minimum

passing distance permitted by the Rules) and Rule-16 (well clear - the minimum passing distance permitted by the Rules). Both terms ‘Safe Distance’ in Rule-8(d) and ‘Well Clear’ in Rule 16 represent a greater distance than ‘close-quarters’. In a close-quarters situation, decisions might have to be taken without time for proper thought. Good time: Good time means ‘early’. There is no specific time at which good time begins. It’ll depend on a particular situation. Maneuvers taken to avoid a close-quarters situation should be taken at a time when the responsible officer does not have to make a quick decision or a decision based on inadequate information. We can say that if a vessel fails to take action in good time, she may find herself in a close-quarters situation. This paragraph didn’t say action is to be taken in good time to avoid a collision. Substantial: Alterations of course alone should be substantial so that they may be readily apparent to another vessel. In restricted visibility, alterations of course and speed should be substantial so that they may be readily apparent to another vessel observing visually or by radar. While taking an action to void a close quarter’s situation with one vessel, the OOW must monitor her action properly so that the action doesn’t result in another close quarter’s situation. (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. Safe Distance: What distance is safe depends on the circumstances; suffice it to say that if you are obligated to take the action, the person on the other vessel should not feel compelled to act also to increase the distance still further. Effectiveness of the Action: If action to avoid collision is required, the mariner must take effective and readily apparent action, whether it be a course change or a speed change or a combination of the two. A course change works better for meeting situations, whereas for vessels crossing at nearright angles, a speed change (perhaps in combination with a course change) often works better. Continuing change of compass bearing would be one indication of the initial effectiveness of the avoiding action. However, an appreciable change of bearing may not be sufficient to establish that the vessels will eventually pass clear of one another. Subsequent action by the other vessel could result in renewed risk of collision. Finally Past & Clear: It means RoC doesn’t exist anymore. The visible signs

are appreciable change in compass bearing, increasing CPA & distance, Etc.

(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 a vessel is obliged to take action to avoid collision with another vessel which is crossing, or which she is overtaking, she may be prevented from making course alterations due to lack of sea room or to the presence of other vessels; in such circumstances it will be necessary to slacken speed or take all way off. In restricted visibility when a close quarters situation cannot be avoided with a vessel forward of the beam, or a fog signal is heard forward of the beam, it will usually be necessary to reduce speed or stop the ship. The speed must also be reduced if it is necessary to allow more time to assess the situation (As per Rule-5, a full appraisal of situation is required) Taking all way off or reversing propulsion: You should refer to ship’s maneuvering booklet to know about her maneuvering characteristics. An OOW should have thorough knowledge about the turning circle of the vessel. It’s a good practice that the bridge team is briefed about the limitations of M/E and the procedures of stopping M/E in case of an emergency. Stoppage time (Sea ahead to zero speed) depends on various factors, such as size of the vessel, present displacement, depth of water, wind, sea conditions, current, etc. Usually the maximum astern power is 60-80% of maximum ahead power. Helm Action in stopping the vessel: Helm action taken in the initial stage of a crash stop, when still moving at high speed, will result in a considerable increase of resistance and reduce the stopping distance. A method which may be used in some circumstances is to put the helm hard over one way then hard over to the other side with the engines on dead slow ahead, then to put the engines full astern. This should reduce the period of applying astern power so that the vessel is less likely to be slewed in the final stage. Crash Stop: To avoid an imminent danger like collision, grounding etc, it becomes necessary to stop the vessel as soon as possible. Crash maneuvering is turning the engine in opposite direction to reduce the ahead speed of the ship. After certain time, the ship stops and starts steaming in astern direction. The procedures of crash stop are as below (it may vary from ship to ship): The bridge informs about the emergency situation and requests E/R for crash stop The Fuel Lever (Starting Lever) is set to Stop Position and the helm is put hard-over to either port or starboard so that speed drops faster. After the stoppage, she may come off the original course line by large amount. For

right handed propelled ship, the bow will cant to starboard. Avoid attempting Emergency Stop of M/E since it takes some times to reset parameters of M/E before a restart is possible

After putting the Fuel Lever to stop position, observe the M/E rpm indicator. The rpm will still be showing for few minutes since the propeller doesn’t stop instantly even after the Fuel Lever is set to Stop Position. At that point, engineers will give stern movement by air only (often called as brake air), i.e. no fuel will be used. This movement is given for a very short period to stop the movement of the crankshaft or the propeller. Ship’s speed (by momentum) will be dropping slowly and few minutes after stop command is given, the rpm will show Zero. When the rpm rests to zero, order full astern directly regardless of whatever speed the vessel might be proceeding with at that moment Finally, the vessel will start to get stern-speed slowly. Damage to Engines: In this type of maneuvering, the main engine is subjected to severe stress and load. To avoid the damage to M/E through a crash stop maneuver and provided that time permits to avoid the danger, it is suggested that a quicker and safer way to stop a vessel would be to stop the engines instantly then, after a delay of three minutes or so, to give slow astern, half astern and full astern, thus avoiding acute cavitations. More recent evidence from ship trials and model tests seems to indicate that many vessels, especially those fitted with diesel engines, could best be stopped by giving ‘full astern’ as soon as possible, but it can generally be said that even if the engines can be made to go astern within one minute of the order ‘stop’ the retarding effect would be small and the risk of damage to the machinery would be great. The above remarks apply to a vessel moving at high speed. The engines can be more readily reversed when the speed is low. For the interest of safety, OOW or Master must not hesitate to do a crash stop. (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. Not to impede to avoid development of RoC: Vessels directed "not to impede" other vessels should take early action to keep clear by wide margins so that a RoC doesn’t develop. The other vessel shouldn't become concerned enough to alter its course or speed, or otherwise feel obligated to act differently from the way it would if the would-be impeding vessel weren't there. Examples: Rule-9(b, c, d) & 10(i) mention about not to impede passage of a vessel, Rule-10(j) mentions about not to impede the safe passage of a power

driven & 18(d)(i) mentions about not to impede passage of a vessel constrained by her draught.

(ii) A vessel required 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. What if RoC exists: The vessel that had been originally directed to not impede the other should retain that burden even after risk of collision arose. That does not mean, however, that the (usually larger) vessel that was not to be impeded continues to have the right of way. If the not-to-be-impeded vessel would be the give-way vessel under the general rules, it has the duty to stay out of the way of the impeding vessel after risk of collision arises because of the application of Rule 17(a)(i). Early action in compliance with Rule 8(f) is compatible with Rule 17(a)(ii), which permits action by the standon vessel. The impeding vessel also continues to have a duty to stay out of the way after risk of collision arises, and does not gain the stand-on status that the general rules might have given it. Both vessels would be obligated to stay out of the way and the impeding vessel would have a double duty to stay out of the way. Example # 1: When a power-driven vessel and a sailing vessel are approaching each other, the power-driven vessel is required by Rule 18(a) to keep out of the way when risk of collision begins to apply, although she may be proceeding along a narrow channel or traffic lane, but this does not relieve the sailing vessel of the obligation to take early action to allow sufficient sea room. Example # 2: If one of two power-driven vessels, crossing so as to involve risk of collision, is required not to impede the passage of the other vessel, she must, in compliance with Rule 8(f), take early action to allow sufficient sea room for the safe passage of the other vessel although the other vessel may be required by Rule 15 to keep out of the way. Full regard to the action: A vessel taking action as per Rule 8(f)(ii) shall take into account the possibility of both vessels taking conflicting actions when there is risk of collision. However, as it is not possible to establish the precise distance apart at which risk of collision begins to apply, a vessel taking early action not to impede should also have full regard to the action which may be taken by the other vessel (as a give way vessel). Rules 14, 15 and 17(c) indicate the form of action to be taken. (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 one another so as to involve risk of collision.

A not-to-be-impeded vessel is not relieved of her obligation to comply with the Steering and Sailing Rules when there is risk of collision. When vessels are in sight of one another and risk of collision exists, a power-driven vessel may be required to keep out of the way of the vessel required not to impede in accordance with Rules 13, 14, 15 and 18(a). In restricted visibility such a vessel is not relieved of her obligation to take avoiding action in ample time when a close quarters situation is developing. When there is an obligation not to impede in restricted visibility Rule 19 applies fully, together with Rule 8(f). Rule-9: Narrow Channels (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. Narrow Channels: What is "narrow" depends on the type of vessel and the circumstances. A "channel" is a natural or dredged lane restricted on either side by shallow waters; it is often marked by buoys. There is no specific width of a narrow channel. The width of narrow channel could be between less than a mile and a few miles. Fairway: A "fairway" is generally in open water, and the water on either side is not much shallower than within the fairway. Fairways are dredged and maintained by the port authority & used to route vessels away from natural hazards, oil platforms, mines, or smaller vessels. Outer Limit of the Channel: Paragraph (a) requires all vessels to navigate on the far right side of a narrow channel, whether or not traffic is approaching from the other direction. If that is not "safe or practicable," however, the mariner is justified in moving closer to the center or even over the center to the left side (providing the traffic permits such action). Usually, the depth of a narrow channel is less from centre line towards either side. (b) A vessel of less than 20 metres 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. Shall not Impede: Rule 8(f) "shall not impede" language says that vessel directed not to impede shall take early enough action that sufficient sea room exists for safe passage. If risk of collision does arise (ideally it should not), the impeding vessel retains its duty to stay out of the way, notwithstanding any stand-on rights the more general Steering and Sailing Rules may have given it. In other words, the vessel directed not to impede should stay well clear!

Only within a narrow: Paragraph (b) gives rights to non-sailing vessels that are over twenty meters long and that can safely navigate only within the narrow channel or fairway. The word ‘only’ implies that many vessels can’t navigate safely outside a narrow channel whereas there

are small vessels (smaller draught) that can safely navigate just outside the narrow channel although they are allowed to use the narrow channel too. If RoC exists: This Rule does not relieve a power-driven vessel which is restricted to the channel from her obligation to keep out of the way of a small power-driven vessel being overtaken or crossing from her starboard side, or of any sailing vessel, if there is risk of collision. (c) A vessel engaged in fishing shall not impede the passage of any other vessel navigating within a narrow channel or fairway. It implies that fishing is permitted when the channel is not being used. In this paragraph, ‘any other vessel’ includes even small power driven vessels, sailing vessels, etc. (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 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. Crossing The Channel: This paragraph prohibits all vessels from crossing a narrow channel or fairway such a way that would impede a vessel that could not safely operate outside of the channel or fairway. Rule 8(f) "shall not impede" language is operative here. If your vessel is directed not to impede another, try to avoid causing the other vessel to change its course or speed. If you blunder into a risk-of-collision situation, the general Steering and Sailing Rules will not apply to you--you will continue to be obliged to stay out of the way. Be mindful, however, that Rule 8(f)(iii) says that the general rules will apply to the vessel you are impeding. Doubt & Sound Signals: The Rule also provides for the vessel constrained to the channel to sound at least five or more short blasts or at least five short and rapid flashes if in doubt as to the intentions of the crossing vessel. Rule 9 says that this sound signal "may" be used--although Rule 34(d) requires its use in case of doubt. (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).

Overtaking: The International Rule 9 requirement for overtaking applies only when the overtaken vessel (in addition to the overtaking vessel) has to take maneuvering action to permit

a safe passing. If the overtaken vessel agrees with the overtaking vessel's passing proposal, then the overtaken vessel is required to "take steps to permit safe passing." If permission from overtaken vessel is not required (i.e. there is sufficient safe sea room to overtake), then this paragraph doesn’t apply to the overtaking vessel. If it is not considered safe for the other vessel to pass the signal of at least five short rapid blasts could be made on the whistle. This signal indicates doubt about the intentions or actions of the other vessel and implies that the vessel ahead does not consider it safe for the vessel astern to attempt to pass. Usually, passage through narrow channel and fairway is well regulated by VHF surveillance from VTIS. Now-a-days, the use of VHF by Pilot/VTIS in such a situation is common in practical. Good seamanship: If safe and practicable, it would be good seamanship to move away from the side of the narrow channel or fairway in which the overtaking vessel intends to pass, to allow a greater passing distance and also to reduce speed in order to decrease the period of running closely parallel to each other. (ii) This Rule does not relieve the overtaking vessel of her obligation under Rule 13. Regardless of a permission required for safe passing, the overtaking vessel has ultimate responsibilities as per Rule-13. (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 requirements in this paragraph offer nothing new--the requirements for lookout, safe speed, needed precautions and Rule 34(e) covering the signal requirement. When two power-driven vessels approaching from opposite directions hear each other’s signals, the vessel stemming the tide should wait until the other has passed clear. (g) Any vessel shall, if the circumstances of the case admit, avoid anchoring in a narrow channel. It’s not strictly prohibited to anchor in a narrow channel. A vessel may require anchoring inside a narrow channel for many overriding situations. A vessel anchored in a narrow channel is likely to impede the safe passage of

other vessels. A vessel which finds it necessary to anchor in a narrow channel should endeavor to do so in a position where she will not obstruct the flow of traffic. If a vessel needs to anchor in a narrow channel due to thick fog and non-operational radar, she should endeavor to do it outside the channel.

Rule-10: Traffic Separation Schemes (a)This Rule applies to traffic separation schemes adopted by the Organization and does not relieve any vessel of her obligation under any other rule. Concept of TSS: The purpose of ships’ routeing is to improve the safety of navigation in converging areas and in areas where the density of traffic is great or where the freedom of movement of shipping is inhibited by restricted sea-room, the existence of obstructions to navigation, limited depths or unfavourable meteorological conditions. Rule 10 adds some extra provisions for traffic management for a number of specially designated areas having high-density traffic, converging traffic, or some exceptional hazard. In these situations, more conventional navigation rules do not provide a desirable margin of safety. The Organization mentioned in the International Rule paragraph (a) is the International Maritime Organization (IMO), a body of the United Nations headquartered in London. Traffic separation schemes are adopted by the IMO after a country (or countries) submits a traffic separation scheme proposal, which must meet specific IMO guidelines. Normally a scheme will not be shown on charts until it has been formally adopted by the IMO. The IMO publishes Ships' Routing, which contains design standards and a list (with diagrams and coordinates) of all adopted traffic separation schemes. The details of TSS can be found in IMO Ships Routeing Guide. Other Rules in TSS: All other Rules of the Collision Regulations continue to apply to a vessel using a TSS. Example – Head on, crossing, overtaking situations, etc are fully applicable in TSS. A power-driven vessel following a traffic lane is not relieved of her obligation to keep out of the way of a vessel seen on her own starboard side to be crossing so as to involve risk of collision. (b) A vessel using a traffic separation scheme shall: When a vessel is considered to be using a TSS: Within the context of Rule-10: She is navigating within the outer limits of the scheme She is not crossing the lanes She is not engaged in fishing within a separation zone. A vessel using an inshore traffic zone is not using the scheme.

(i) proceed in the appropriate traffic lane in the general direction of traffic flow for that lane; General Direction of Traffic Lane: A vessel intends to use TSS must proceed in the right lane, i.e. along the general direction of the lane. The general direction of traffic flow within a traffic lane is indicated by arrows on the charts. (ii) so far as practicable keep clear of a traffic separation line or separation zone; The second rule requires vessels "so far as practicable" not to get too close to a traffic separation line or zone so as not to drift accidentally into the lane of oncoming traffic or create doubt about whether or not it is using the traffic separation scheme. (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. The third rule, governing vessels entering or leaving a traffic separation lane, requires a small angle of approach or departure to differentiate that vessel from one crossing the scheme. (Crossing instructions are in Rule 10(c).) (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. Crossing a traffic lane may be a disturbance to the traffic flow pattern and increase the risk of collision. Many schemes are short, and you can go around, not through them. Crossing long schemes at right angles to the general direction of the traffic flow implicates vessel's intentions and minimizes the time the crossing vessel spends in the scheme. The angle of crossing is determined by the vessel's heading, not its course made good. When a crossing vessel encounters a vessel using a traffic separation scheme, the vessel that is required to keep out of the way is determined by Rule 15 (Crossing Situations). Fishing vessels, sailing vessels, and power-driven vessels less than twenty meters in length--see paragraphs (i) and (j)--that are crossing shall always stay out of the way of a vessel following a traffic separation lane, but be aware that the larger vessel in the traffic lane does not have absolute rights; see Rule 8(f)(iii). (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.

Inshore Traffic Zone: A routeing measure comprising a designated area between the landward boundary of a TSS and the adjacent coast, to be used in accordance with the provisions of Rule 10(d), as amended, of the International Regulations for Preventing Collisions at Sea (Collision Regulations), 1972. Inshore traffic zones have been established alongside some traffic separation schemes with the intention of keeping coastal shipping away from traffic passing through the adjacent traffic lanes. Contrary to this, there are some TSS following which a ship takes longer time than it would’ve taken to make her passage between two near-by ports had she followed the inshore traffic zone. But local rules regarding some TSS around the world prohibit doing so unless proper permission or exemption is taken. A severe fine may be imposed for breaching such local rules. Mariners should consult with appropriate Sailing Directions, ALRS Volumes, Chart Notes, etc for the details of the requirements. The Rule recognizes that sailing vessels and small power-driven vessels often depend on being near the coast. (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. An OOW should have clear conception that he may use the ISTZ in case of an emergency to avoid an immediate danger. Example – If a vessel’s steering fails in a busy traffic lane, she could be pulled out of the lane and head for an anchorage within an ISTZ. (e) A vessel other than a crossing vessel or a vessel joining or leaving a lane shall not normally enter a separation zone or cross a separation line except: Separation Zone or Line: A zone or line separating the traffic lanes in which ships are proceeding in opposite or nearly opposite directions; or separating a traffic lane from the adjacent sea area; or separating traffic lanes designated for particular classes of ship proceeding in the same direction. in cases of emergency to avoid immediate danger; to engage in fishing within a separation zone. (f) A vessel navigating in areas near the terminations of traffic separation schemes shall do so with particular caution.

Because of the concentration of converging, diverging and crossing traffics at the termination of a TSS, you should exercise particular caution, especially when the visibility is restricted.

Paragraph (f) makes it clear that the mariner is also required to proceed with caution near the ends of traffic separation schemes that do not have precautionary areas. (g) A vessel shall so far as practicable avoid anchoring in a traffic separation scheme or in areas near its terminations. The reason for such rule is that anchored vessel in or near a TSS causes traffic congestion and confusion to mariners. (h) A vessel not using a traffic separation scheme shall avoid it by as wide a margin as is practicable. The smooth operation of a traffic separation scheme depends on the absence of outside disturbances. A vessel following a traffic lane may get confused seriously by the adjacent traffics outside the TSS. A vessel not using a traffic separation scheme must stay far enough away that vessels within the scheme are not obligated, via any other navigation rule--see Rule 8(f)(iii)--to take action inconsistent with the flow of traffic. (i) A vessel engaged in fishing shall not impede the passage of any vessel following a traffic lane. Fishing is permitted within a traffic lane so long as the fishing vessel does not "impede" other vessels following the traffic lane and does not proceed against the general direction of flow when fishing within a lane. If the vessel engaged in fishing follows a course that obliges a vessel following the traffic lane to alter course or speed, then the fishing vessel has impeded the other vessel and is therefore in violation of this requirement. A vessel engaged in fishing outside the outer limits of a TSS must not allow her nets to extend into a traffic lane in such a way as to impede the passage of a vessel following the lane. (j) A vessel of less than 20 meters in length or a sailing vessel shall not impede the safe passage of a power-driven vessel following a traffic lane. Here Rule-8(f) comes into picture which has been discussed earlier, i.e. about ‘Impeding the safe passage of a power driven vessel’. (k) A vessel restricted in her ability to maneuver when engaged in an operation for the maintenance of safety of navigation in a traffic separation scheme is exempted from complying with this Rule to the extent necessary to carry out the operation.

Note: Explanation for (k) and (l) have been given together below.

(l) A vessel restricted in her ability to maneuver when engaged in an operation for the laying, servicing or picking up of a submarine cable, within a traffic separation scheme, is exempted from complying with this Rule to the extent necessary to carry out the operation. Vessels engaged in the maintenance of navigation safety, such as buoy tenders, are exempted only while they are restricted in their ability to maneuver and only to the extent needed to carry out their work. But they are normally expected to comply with the provisions of Rule 10 and to either cross traffic lanes at right angles or proceed along them in the general direction of traffic flow. These vessels must exhibit the lights or shapes prescribed in Rule 27(b) to indicate their RAM status. Operations likely to interfere with normal separation scheme traffic are usually promulgates by notices to mariners through various equipment and services. Special signal The International Code two letter signal ‘YG’ has the meaning ‘You appear not to be complying with the traffic separation scheme’. The Master of any vessel receiving the signal by whatever means should take immediate steps to check his course and position and any further action which may be appropriate to the circumstances.

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. Sight of one another: Rules 11 through 18 apply to vessels in sight of one another. Rule 3(k) says that vessels shall be deemed to be in sight of one another only when one can be observed visually from the other. If one vessel fails to sight the other only because of an inadequate lookout (Rule 5), then that vessel is not excused from complying with the Rules in this section. The Rules in Section II do not apply to a vessel which has detected another

vessel by radar, and has established that risk of collision exists, if the other vessel cannot be sighted visually. There might be a situation where vessels may initially have to comply with Rule-19, then subsequently have to comply with the Rules of Section II when they come into visual sight of one another.

Theory of this Rule: The Rules in this section in most cases assign to one vessel in a two-vessel encounter the primary responsibility for staying out of the way of the other. The vessel obliged to stay out of the way of the other is called the "give-way" vessel; the other vessel is called the "stand-on" vessel. The theory behind these Rules is that the give-way vessel is the one better able to stay out of the way, although in practice this is not always the case. The execution of these Rules depends on the operator of each vessel being able to assess the other's relative position, course, speed, and intentions. Hence the Rules in this section depend on good visibility (day or night). Rule-12: 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: Rule 12 tells which of two sailing vessels must stay out of the way of the other and covers all situations except overtaking. Rule 13 outranks Rule 12 and says the overtaking vessel shall stay out of the way of the overtaken vessel, whether it is a sailboat overtaking another sailboat or a sailboat overtaking a power-driven vessel. When two sailing vessels are approaching one another so as to involve risk of collision, Rules 8, 13, 16 and 17(a), (b) and (d) apply as well. Rule 12 will not apply if one of the vessels under sail is also using propelling machinery as such a vessel is considered to be a power driven vessel. (i) when each has the wind on a different side, the vessel which has the wind on the port side shall keep out of the way of the other; Windward side: The side from which a true wind is blowing Leeward side: The side towards a true wind is blowing Wind on different sides of two sailing vessels: The wind on the port side of a vessel means the windward side is port side and the vessel is said to be on the ‘port tack.’ Similarly, the wind on the starboard side of a vessel means the windward side is starboard side and the vessel is said to be on the ‘starboard tack.’ A sailing vessel with the wind on the starboard side (that is, starboard side is the windward side) carries its mainsail on the port side and stands on for vessels with the wind on the port side. Or, as more commonly expressed, the starboard-tack boat has the right-of-way over the port-tack boat. This is true even if the port-tack boat is close-hauled and the starboardtack boat is running downwind.

(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; Wind on same side of two sailing vessels: When both vessels have the wind on the same side, the vessel to windward is required to stay out of the way. (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 the starboard side, she shall keep out of the way of the other. If you can't tell on which side the other vessel's sails are carried and you are on port tack, you keep out of the way of the other. (b) For the purposes 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 on which the largest fore-andaft 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. Paragraph (a) of this Rule requires that any vessel overtaking another keep out of the way, even if another rule requires otherwise. In overtaking situations, look first to Rule 13. Overtaking in Narrow Channel & TSS: Rule 13 requires overtaking vessels to put aside the other "shall not impede" requirements and to keep out of the way of the vessel to be overtaken. If a vessel impedes the passage or safe passage of a vessel (not to be impeded) mentioned in Rule - 9(b), (c) & 10(i), (j), and the latter vessel is overtaking the former, the latter vessel must do so as per Rule-13. When vessels are in sight of one another and there is risk of collision the prime responsibility for keeping out of the way rests with the overtaking vessel. A hampered vessel which is unable to make a substantial alteration of course will normally be able to avoid collision by reducing her speed. Prime responsibility for keeping out of the way is allocated to the overtaking vessel in every case as that vessel must be proceeding at greater speed and is more likely to sight the vessel being overtaken at an early stage. (b) A vessel shall be deemed to be overtaking when coming up with another vessel from a direction more than 22.5 degrees 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 stern light of that vessel but neither of her sidelights.

If the approaching vessel is within the stern light sector of another vessel but their courses will bring them no closer together than, say, three miles, then there is no risk of collision and no overtaking situation exists. The visibility of sidelights is in the range of 1 to 3 miles, depending on length of vessels. Overtaking continues even as the overtaking vessel moves out of the stern light sector and pulls abeam of and then ahead of the overtaken vessel. It ends only when the maneuver has been completed and the other vessel is finally past and clear. (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. If you see a white light and later a colored sidelight, either you could be overtaking and have come up enough to move into horizontal sector of the sidelight, or you could be crossing or meeting head-on, having first seen the brighter white masthead light (visibility range 2-6 miles) and then later the less visible colored sidelight (visibility range 1-3 miles). If you are in doubt, assume that you are overtaking and keep out of the way of the other vessel. (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. The overtaking vessel cannot (by any action of its own) shift its give-way status to the other vessel. The overtaking vessel retains her duty of keeping clear of the other vessel until the risk of collision has passed, that is, until the overtaking vessel "is finally past and clear." This requirement is a reiteration of the Rule 8. This paragraph has been included to cover the case of one power driven vessel overtaking on the starboard side of another power driven vessel and then turning left across the other's bow. In an ordinary crossing situation, the vessel on the right would have been the stand-on vessel. If this were also the case of the overtaking vessel crossing the other, the overtaken/stand-on vessel would suddenly become the crossing/give-way vessel and might not have enough maneuvering room. However, if she is at a considerable distance away from the overtaken vessel so that there is no risk of collision when the overtaking vessel passes the overtaken vessel, Rule-13 would not apply at that time, and the other vessel (overtaken) would be obliged to keep clear in a subsequent crossing situation bringing risk of collision between the same two vessels.

Coming up from a direction 22.5" abaft the beam: A power-driven vessel which approaches another power-driven vessel from a direction approximately 22.5" abaft her beam may be in doubt as to whether she is an overtaking vessel or a crossing vessel. There should not be any doubt at night because a crossing situation is indicated if a side-light is seen, but the aspect cannot be determined accurately by day. Rule 13(c) requires such a vessel to assume that she is overtaking and keep out of the way. As the other vessel may ascertain that a crossing situation exists, and take action to avoid a vessel crossing from her own starboard side, the vessel which is to starboard should preferably turn on to a parallel course and subsequently pass ahead. Here Rule-13(c) has precedence over Rule-15. Interaction: Keeping well clear while overtaking is especially important because the potentially strong hydrodynamic interactive forces may cause one or both vessels to veer off course. The details of interaction has been discussed in Seamanship Section – Look for it in www.nongor.net website. Rule-14: Head-on Situation (a) When two power-driven vessels are meeting on reciprocal or nearly reciprocal courses 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. Application: Rule 14 applies only to power-driven vessels meeting head-on with another power-driven vessel. Each power-driven vessel approaching another head-on is required to alter her course to starboard for a port-to-port passing--you must turn to starboard, never port. (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. Aspect: The aspect is how the other vessel appears to you. This paragraph says --look at the aspect of the other vessel. The decision should not depend on the course made good over the bottom, so do not delay your action until the path of the other vessel has been plotted. Sidelights: In order to avoid possible dark lanes immediately ahead of a ship the sidelights are screened so as to show approximately 2” (between 1 & 3 degrees, see Annex 1, Sec 9(a)(i)) across the bow, i.e. each sidelight overlaps about two (One to three) degrees into the other light's horizontal sector. As a result, there will be approximately a four (two to six) degree sector directly ahead of a vessel in which both sidelights may be seen. If the sidelights were not permitted to show across the bow there would be a theoretical 'dark lane'

ahead which could result in vessels meeting exactly end-on being unable to see each other's sidelights.

Visibility of Sidelights: The visibility of sidelights ranges between 1 and 3 miles. Because sidelights will not have exactly the same intensities and because the human eye is not equally sensitive to red and green light, one sidelight may appear before the other, even if you are in a head-on situation. It is also difficult to see colors at low light intensities--a colored light will look the same as a dim white light. Use your binoculars. The effect of yawing must also be taken into account. (c) When a vessel is in any doubt as to whether such a situation exists she shall assume that it does exist and act accordingly. When a power-driven vessel is in doubt as to whether a meeting or crossing situation exists, or is in doubt as to whether the approaching ship is an ordinary power-driven vessel or a hampered vessel, she should assume that Rule-14 applies and act accordingly. Rule-15: Crossing Situation When two power-driven vessels are crossing so as to involve risk of collision, the vessel which has 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. Application: This rule applies between two power-driven vessels if RoC exists while crossing. Towing vessels with their tows are considered to be ordinary power-driven vessels unless they are severely restricted in their ability to deviate from their courses. The crossing rule applies only to vessels in visual sight of one another. It doesn’t apply when your radar screen shows perfectly clearly the approach of another vessel in a "crossing situation"; if you can't see the other vessel, Rule 15 does not apply and Rule 19 does. Impediment Vs Crossing: These provisions of ‘not to impede’ apply to small power-driven vessels, sailing vessels, and fishing vessels in narrow channels or fairways, and in traffic lanes. Once risk of collision arises, however, Rule 15 takes over and may change the obligations of the vessels. Thus, if you are operating a large vessel and are in a narrow channel, narrow fairway, or traffic lane, and you encounter a crossing smaller vessel (directed not to impede other vessels) involving risk of collision, you must obey Rule 15, even though the smaller vessel is also required to keep clear of your way. Avoid Crossing Ahead: The requirement to avoid crossing ahead only applies in a crossing situation in which there is risk of collision. This requirement

comes into picture due to the fact that a stand-on power-driven vessel in a crossing situation is permitted to act at an earlier stage

but must not alter course to port. These restrictions on maneuvers are intended to reduce the possibility of conflicting action being taken. It does not apply at long ranges, before risk of collision begins to apply, or to cases in which the bearing is appreciably changing. Vessel lying stopped: A power-driven vessel which is under way but stopped must, unless she is not under command or restricted in her ability to maneuver, keep out of the way of another power driven vessel on her own starboard side, in compliance with Rule-15. The other vessel must not be expected to take avoiding action. A vessel lying stopped with her engines ready for maneuver must show any special lights or shapes to get privilege and must comply with Rules 14, 15 and 18. Rule-16: Action by 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. Application: Rules 12, 13, 15, and 18 (all of which apply to vessels in sight of each other) direct one of two approaching vessels to keep out of the way of the other. Rule 16 applies to the give-way vessel, the one directed to stay out of the way of the other. Rule 17 assigns more complicated responsibilities and privileges to the other vessel, the stand-on vessel. Rule-8 Vs Rule-16: Some of the principles in Rule-8 and Rule-16 are same, but the language differs. Rule-16 says "take early and substantial action"; Rule-8 says take action that is "positive, made in ample time." Rule-16 says take action "to keep well clear"; Rule-8 says take action that will "result in passing at a safe distance." Rule-16 says take the prescribed action "so far as possible"; Rule-8 says take the action "if circumstances of the case admit." Although the language varies, the meaning is essentially the same. Avoid Crossing Ahead: Depending on the situation, the give-way vessel may or may not be allowed to cross ahead of the stand-on vessel. Rule 15 does not permit (under normal circumstances) a power-driven give-way vessel to cross ahead of a power-driven vessel. A give-way vessel can cross ahead of a sailing vessel, hampered vessel, or vessel it is overtaking. If you cross ahead of a stand-on vessel, remember that you must pass "at a safe distance" (Rule 8) and keep "well clear" (Rule 16).

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. Application: This rule applies only in situations covered by Rules 12, 13, 15, and 18, which require one vessel to keep out of the way of another. These four Rules apply only when the two vessels are in sight of one another and only when risk of collision exists. Duty of Stand-on Vessel: A stand-on vessel has more complicated responsibilities than that of a give-way vessel but the primary obligation of a stand-on vessel is to hold its course and speed. However, a stand-on vessel does not necessarily have to remain on exactly the same compass course and speed. A little change of course and speed wouldn’t affect much the crossing situation. Also, she may need to alter her course and speed to avoid another imminent danger. The purpose of the action (keep her course & speed) required by a stand-on vessel is to enable the give-way vessel to predict the action of the stand-on vessel and be able to keep out of its way. (ii) The latter vessel may however take action to avoid collision by her maneuver alone, as soon as it becomes apparent to her that the vessel required to keep out of the way is not taking appropriate action in compliance with these Rules. Why many give-way vessels don’t take action on time: Among many possible reasons, there could be two vital ones – the competence of the watch keepers and negligence by bridge team. Appropriate action: An appropriate action is always taken in compliance with RoR. An inappropriate action is not an action at all or an ineffective action. When stand-on vessel should take action: When it becomes apparent to a stand-on vessel that the give-way vessel is not taking appropriate action, the stand-on vessel ‘may’ take appropriate action to achieve a safe passing distance. The rule didn’t say that at that point the stand-on vessel ‘must’ start maneuvering. She should use appropriate wake-up signals as per Rule34(d) to know the intension of the give-way vessel if the give-way vessel is not taking appropriate action. A stand-on vessel is permitted to keep her

course and speed until collision cannot be avoided by the give-way vessel alone.

A stand-on vessel may not take action until the give-way vessel has got time to assess the situation and starts taking avoiding action. Action in haste by the stand-on vessel may result in both vessels taking simultaneous actions and running into danger. It’s difficult to determine exactly when a stand-on vessel would take action. It depends on various conditions, such as open waters, congested waters, size of the vessel, maneuverability of the vessel, rate of approach, CPA, TCPA, etc. The stand-on vessel should preferably take action before reaching the stage where a give-way vessel’s action alone is not sufficient to avoid the collision. If two high speed power-driven vessels are in a crossing situation so as to involve RoC and the give-way vessel doesn’t take actions even at 3 miles range, it might be too late for stand-on vessel to initiate her actions. (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. This paragraph illustrates a critical situation where the only action is to just avoid the contact. Rule 17(c) does not apply at this stage. Paragraph (c) says that a stand-on power-driven vessel shall, if the circumstances of the case admit, not alter course to port for a vessel on her own port side. The usual starboard alteration recommended for a stand-on vessel as an early avoiding action would at this point swing her stern into the oncoming bow of the giveway vessel. At this stage, a stand-on power-driven vessel is permitted to turn to port for another power-driven vessel on the port bow. If collision is inevitable: The master or OOW should take a prudent action to minimize the impact of the collision. A contact with sliding narrow angle would cause less damage that it would have done had the angle been broad. Stop engines and use your helm judiciously and try to make the impact forward of the collision bulkhead. When a vessel is approaching on the port bow an alteration to starboard might as well be the worst possible action to take. (c) A power-driven vessel which takes action in a crossing situation in accordance with sub-paragraph (a) (ii) of this Rule to avoid collision with another power-driven vessel shall, if the circumstances of the case admit, not alter course to port for a vessel on her own port side. What action a stand-on vessel should take: A stand-on power-driven vessel must not alter course to port to avoid the give-way power-driven vessel crossing from her own port side since the give-way vessel is not relieved of her obligation to keep out of the way and may alter her course to starboard

at the last moment. However, paragraph (b) has given a stand-on vessel a freedom to take any action to avoid the collision.

As a give-way vessel is usually directed to avoid crossing ahead of a standon vessel as per Rule-15, a reduction of speed by the stand-on vessel would make it more difficult for the give-way vessel to pass astern, which is her usual method of keeping clear of the stand-on vessel. If made in sufficient time, an alteration of course would be the best action by the stand-on vessel. Alteration of speed comes into effect slowly. In some cases, simultaneously increasing speed and alteration of course could be a good option for a standon vessel. (d) This Rule does not relieve the give-way vessel of her obligation to keep out of the way. In this rule, a stand-on vessel is permitted to take actions in two stages – an early action by paragraph-a(ii)) and a delayed action by paragraph-b. Even a stand-on vessel takes action in any of these stages, the give-way vessel must not assume that she is relieved of her obligation to keep out the way of the stand-on vessel with a safe distance. Rule-18: Responsibilities between Vessels Except where Rules9, 10, and 13 otherwise require: This rule lists various classes of vessels in an order of privilege. With some exceptions, more maneuverable vessels are directed to keep out of the way of less maneuverable vessels. Rules 9(b), 9(c), 9(d), 10(j), 10(i) and 13 overrides Rule 18. (a) A power-driven vessel underway shall keep out of the way of: a vessel not under command; a vessel restricted in her ability to maneuver; a vessel engaged in fishing; (iv) a sailing vessel. Note: A power-driven vessel anchored or aground must display the required lights and shapes to indicate its status. (b) A sailing vessel underway shall keep out of the way of: a vessel not under command;

a vessel restricted in her ability to maneuver; a vessel engaged in fishing. Note: No explanation included A vessel engaged in fishing when underway shall, so far as possible, keep out of the way of: a vessel not under command; a vessel restricted in her ability to maneuver.

Note: A vessel engaged in fishing when underway may not always be able to take effective avoiding action in sufficient time to keep out of these vessels.

(d) (i) Any vessel other than a vessel not under command or a vessel restricted in her ability to maneuver 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. Here "if the circumstances of the case admit" relies on the judgment of the operator of the vessel approaching the vessel constrained by draft. This introduces uncertainty for the constrained vessel because the other vessel’s judgment may be wrong. The words "shall not impede the passage" requires the non-constrained vessel to keep out of the way of the CBD vessel while she is at long range. However, these two vessels get close enough so as to involve risk of collision, the constrained vessel will be obligated to act in accordance with other rules (say Rule-15 & 16), which may make it the give-way vessel. But at the same time, the non-constrained vessel will in all cases continue to be responsible for keeping out of the way. On the other hand, if a power driven vessel is crossing with a CBD vessel on her port side, the power-driven vessel should take early action to avoid development of RoC. If RoC develops, the CBD vessel becomes the give way vessel. If necessary, the power-driven vessel should take action in accordance with Rules 8(f)(ii) and 17(a)(ii). She should avoid altering course to port in accordance with Rule 17(c). (ii) A vessel constrained by her draught shall navigate with particular caution having full regard to her special condition. Since there is an uncertainty that the other vessel recognize the CBD vessel on time and take appropriate action, the constrained vessel must be ready to take collision-avoiding action at all times, i.e. she should proceed with safe speed and have her engines ready for maneuver. Also, she should exhibit the signals as per Rule-28. (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.

Rule 18 directs seaplanes to keep well clear of other vessels if possible. Otherwise, a seaplane is to follow the Rules as would a comparable powerdriven vessel. While landing and taking off, seaplanes cannot effectively turn, but they can maneuver when taxiing. Vessels operating in the vicinity of a seaplane taking off or landing should note, as a precaution, the pilot's forward visibility may become completely blocked by the aircraft's raised nose. The hovercrafts, hydrofoils and air-cushion vessels are not classed as seaplanes, even when operating in the non-displacement mode, but are to be considered as power-driven vessels. It means a seaplane shall keep well clear of these vessels and avoid impeding their navigation. (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; As per this paragraph, a WIG craft shall keep well clear of all other vessels including seaplanes and avoid impeding their navigation. (ii) a WIG craft operating on the water surface shall comply with the Rules of this Part as a power-driven vessel. Special Case: When RoC exists between the following vessels, both vessels should take action to avoid collision. Alterations of course should preferably be to starboard, in accordance with the principles of Rules 14, 15 and 17(c). NUC Vs RAM -

NUC Vs NUC

RAM Vs RAM, etc

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. In or near restricted visibility: There is no specific range within which an area would be considered as an area of restricted visibility for the conditions mentioned in Rule-3(l). For

instance, if visibility is restricted by haze to ten miles (in clear weather, it may be 12 miles), you would not be in an area of restricted visibility. On the other hand for instance, in open water, you should consider that you’re in or near an area of restricted visibility if you cannot see five miles in all directions. In confined waters, this distance may be less. Usually, a Master’s standing orders and/or company policy state the range of visibility at which the presence of Master is required at bridge. Your vessel may be in an area of good visibility but may also be close to a fogbank concealing one or more vessels. Even though you are in the clear visibility, you must follow Rule 19 and sound the signal required by Rule 35. If you’re in an area of good visibility and a vessel emerges from the fogbank and comes in sight of one another, you must follow Rules 11 through 18 and sound any signals required by Rule 34. It is therefore possible for you to be following at the same time rules for good visibility and the rules for restricted visibility. You must assess the situation before you determine which rules shall apply. (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 maneuver. Speed in Restricted Visibility: The decision to reduce speed in an area of restricted visibility depends on various conditions, such as the range of visibility, vessel’s stopping capability, traffic density, open or congested waters, etc. If the area of restricted visibility is not very large and there is open water with less traffics, it might be rather prudent to speed up and clear that area quicker. Readiness of Engines: It’s mandatory for a power-driven vessel to have her M/E ready for immediate maneuver in restricted visibility. The bridge should give sufficient notice to E/R to prepare the engines and the E/R should be manned. Master must remember that if collision takes place due to the fact that speed was not reduced due to commercial reasons, he would be guilty of an offence for not complying with this obligation. Ship operators MUST not compel the Master to violate this requirement. (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.

This paragraph emphasizes to have due regards to the conditions of restricted visibility while doing a closer scrutiny of Rules 4 to 10 same time. Again the key words come into picture – maintain safe speed, use radars, determine RoC, keep look out, take appropriate actions, etc. It’s imperative to strictly comply with the check list of restricted visibility mentioned in Bridge Procedures Guide and/or in Company Manuals. (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 shall be avoided: Detection by radar alone: It means the detection of other targets is done not by sight (visual) and hearing (fog signal). Determining risk of collision: Rule-7(b) co-relates this paragraph. A detailed discussion has been done about it in Rule-7. Development of a close-quarters situation: Rules 8(c), 19(d) and 19(e) refer to a close-quarters situation. In restricted visibility, the range at which a close-quarters situation between two vessels could be considered depends upon various conditions, such as, open or congested water, present speed of the vessels, etc. There is no specific range for it. Usually a 3-mile range could be taken for a close-quarters situation. Sometimes, we consider the audibility range of sound signaling equipment to be the determining factor of the range of a close-quarters situation. But it’ll always depend upon the prudent judgments of the Master or OOWs. Ample time: This is explained in Rule-8(a). If RoC exists, a vessel should take avoiding action in ample time to avid the collision. Stand-on vessels: In restricted visibility, there is no stand-on vessel. There is no requirement of maintaining course and speed by one vessel. Alteration of speed: An alteration of speed or change of both course and speed can be made instead of an alteration of course alone.

(i) an alteration of course to port for a vessel forward of the beam, other than for a vessel being overtaken; Alteration to port: By the words ‘so far as possible’ this paragraph leaves an option for a vessel to make an alteration to port if a close-quarters situation is developing and/or risk of collision

exists due to some special circumstances, such as, lack of sea room to starboard or to the presence of other vessels, etc. If an alteration to port is required, it must be done early and a large alteration is always encouraged when avoiding a close-quarters situation with a vessel approaching from ahead or fine on the bow. A vessel may alter in either direction when she approaches from astern of a vessel being overtaken (i.e. the overtaken vessel is forward of the beam of overtaking vessel). (ii) an alteration of course towards a vessel abeam or abaft the beam. Abeam or abaft the beam: Abeam is a perpendicular line to the centerline of the vessel. Abaft the beam means behind abeam. For easy reference and convenience, an OOW usually assumes the bridge wings as the points of abeam - port beam and starboard beam. A vessel abeam (at beam) doesn’t necessarily mean that she is approaching towards the bridge wing of own vessel. (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. If risk of collision does not exist: If it has been determined that risk of collision does not exist a vessel is not required to reduce her speed to the minimum at which she can be kept on her course. Example – two vessels proceeding in correct sides of a narrow channel in opposite directions and one vessel may hear the fog signal of another vessel but this doesn’t mean that a RoC exists. RoC not determined & a vessel hears a fog signal ahead: It easier to hear the other vessel's signals when a vessel is stopped. Once a fog signal of another vessel is heard forward of the beam, you can’t conclusively say what the other vessel is doing. She may be making way, stopped, or anchored. Determine whether RoC exists using all available means as per Rule-7.

Once the fog signal is heard forward the beam, a vessel must reduce her speed to the point of bare steerageway. Do not change course until you know the other vessel's position, course, and speed. If you cannot quickly clarify the situation, do not continue blindly into the great unknown. Stop your vessel until you establish the location and intentions of the vessel(s) ahead and if a RoC exists. A vessel which hears two pronged blasts from another vessel must not assume that the other vessel will remain stopped.

Direction of Fog Signal: The direction of sound signals may be misleading in fog. The exact bearing of a sound signal can’t be determined always. That’s why, even when you hear a fog signal abeam or slightly abaft the beam, you should reduce speed to assess the situation. A vessel can’t avoid a close-quarters situation: If a close-quarters situation cannot be avoided, with a vessel forward of her beam, the speed must be reduced to the minimum at which a vessel can be kept on her course and she must do so in ample time without waiting for a close quarters situation to develop. Taking all way off: A vessel which cannot avoid a close quarters situation with another vessel forward of her beam might as well be expected to reverse her propulsion and take all her way off. When a vessel with a right handed propeller falls astern, the bow cants to starboard due to transverse thrust and the vessel may come off the original course significantly to cause confusion to the other vessel. One of the advantages of taking all way off is that the impact of collision will be minimum if contact occurs (God forbids!) forward of the collision bulkhead. Navigate with extreme caution: There is no better one than the caution that ensures avoidance of a collision. Some examples of extreme cautions:Have full regards to the circumstances and conditions of restricted visibility Ensure good and effective look out. Ensure that appropriate manning level is maintained on bridge Comply with the check list of Restricted Visibility as mentioned in OCIMF Bridge Procedures Guide Use all available means to determine a RoC Don’t take action basis scanty radar information Don’t start altering course soon after hearing a fog signal heard forward of the beam Proceed with safe speed. Reduce speed or even revere your propulsion if necessary

Written By -

Reviewed By –

Capt. Md. Safiul Azam Capt. Shawkat Hossain Master Mariner, UK

Master Mariner, Singapore

Date prepared this Made Easy: 28th February 2015 Date published in www.nongor.net : 6th March 2015