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Key factors to avoid collision at sea -Masters navigational guidance

Avoiding a collision or a close quarter situation with other vessels or any other hazards to navigation is the most critical activity conducted at sea. Upon the watchkeeper's diligence rests the safety and security of the ship, the entire crew, the cargo, and the environment. It is a demanding activity, requires support, encouragement, motivation, self-discipline and a high standard of professionalism.

Collision might be defined when a ship strikes to or being struck by another ship, whether underway, anchored, or moored. To prevent disaster, watchkeeping officers must always comply with the International Regulations for Preventing Collisions at Sea. Compliance not only concerns the conduct of vessels in sight of one another but also under restricted visibility conditions. Under the steering and sailing rules, they must display the correct lights and shapes and make use of appropriate sound signals in poor visibility.

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Furthermore, when a vessel becomes disabled, she must display correct lights and shapes to alert other traffic regarding her status of "Not Under Command." However, a vessel drifting close to a port with her engines deliberately slow down is not, for example, a "vessel not under command" as defined by Rule 3(f) of the COLREGS.

Caution should always be observed when approaching other vessels. Vessels may not be displaying their correct lights or shapes, or indeed their signals could be poorly positioned and obscured by the ship's structure when approached from specific directions. In sea areas where traffic flow is regulated, such as port approaches and traffic separation schemes, it may be possible to anticipate movements from certain ship types. In these circumstances it is prudent to allow extra sea room, as long as it is safe to do so.

In general, early and positive action should always be taken to avoid a close-quarters situation, and once an action has been taken, the O.O.W. should always check to make sure that the action taken is having the desired effect. V.H.F. radio should not be used for collision avoidance purposes. Valuable time can be wasted attempting to make contact, since identification may be difficult, and once a connection has been made misunderstandings may arise. In clear weather, the risk of collision can be detected early by taking frequent compass bearings of an approaching vessel to ascertain whether the bearing is steady and the vessel is on a collision course. However, care must be taken when approaching huge ships, ships undertow, or ships at close range. An appreciable bearing change may be evident under these circumstances, but in fact, a risk of collision may remain.

In restricted visibility, the conduct of vessels is specifically covered by the International Regulations for Preventing Collisions at Sea. In these conditions, radar and, in particular, electronic radar plotting can be effectively used for assessing the risk of collision. The O.O.W. should take the opportunity to carry out radar plotting and observation practice in clear visibility whenever possible.

The Master and all watchkeeping officers must be fully conversant with the latest edition and amendments of the International Regulations for Preventing Collisions at Sea. The O.O.W. is to take frequent and accurate compass bearings of approaching ships to detect the risk of collision early. Such risk may sometimes exist when an appreciable bearing change is evident, particularly when approaching a large vessel or a tow or when approaching a ship at close range. He is to take early and positive action following the applicable Collision Regulations and confirm that such action has the desired effect.

Full use is to be made of radar and ARPA in assessing if the risk of collision exists. O.O.W. must not become complacent and rely solely on information from ARPAs. On ocean passages, there should be no need for vessels to pass at close quarters, and early and prompt action must always be taken. For vessels using ECDIS, the O.O.W. must be aware that vessels not acquired and tracked by ARPA will not appear on the ARPA overlay on the ECDIS display. It is for this reason that ECDIS alone should not be used as a collision avoidance tool.

Maintaining a safe speed

Every vessel is required to proceed at a safe speed at all times in any condition of visibility so that she can take proper and effective action to avoid collision and be stopped within an appropriate distance. When determining a safe speed, rule 6 of the Collision Regulations must be referred. Key factors to take into account are visibility, traffic density, and vessel maneuverability.
Therefore, to determine a safe speed, all of the above factors must be taken into consideration. It is impossible to give figures here as every situation is different, and ship types vary in design and propulsion. However, the Master has to ensure that he and his deck officers are fully aware of the safe speed for his ship which will always be dependent on the prevailing circumstances and conditions.

Caution must be exercised when navigating in regions where high-speed craft (e.g., hydrofoils and hovercrafts) are operating. While these crafts can maneuver quickly, they are still required to comply with the Collision Regulations. Accordingly, the Master and O.O.W. on a conventional ship sighting a high-speed craft must never assume because of the additional maneuverability that these crafts will give way. Both the high-speed craft and conventional craft should act according to the Collision Regulations. Only by obeying the regulations will the risk of collision be removed.

Surveys and Gathering Information

At the earliest opportunity after a collision, the damaged vessels will be surveyed. The surveyors appointed on behalf of each owner will conduct joint surveys of both vessels on a without prejudice basis, usually accompanied by the vessel's class surveyor.

Where there has been serious damage, the hull and P&I insurers of each vessel will probably also arrange a further survey to establish the speed of the ship and the angle of collision. Lawyers may be sent to the vessels to interview crew and other witnesses and to inspect logbooks, charts and other records.

Insurance claim

Almost any collision between two ships will involve insurers, given the near-certainty of some measure of damage requiring repair. There are two slightly surprising aspects to conventional collision insurance; one is that under its running down clause, a vessel's hull policy covers liability to third parties and the other is that cover only extends to three-quarters of the liability, the other quarter being borne by the vessel's P&I club.

Nowadays, the proportion of risk borne by the hull insurers can vary from all to nothing, with the balance usually being covered by the P&I club. The P&I club will typically also include other consequential loss and damage resulting from a collision including personal injury, pollution, wreck removal and damage to cargo on board the vessel entered with the club. Because of the club's liabilities' potential scale, it will usually take the lead role in dealing with a serious collision.

Further reading: Collision accident handling checklist

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