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Key factors to avoid collision at sea -Masters navigational guidance

Collision – includes ships striking or being struck by another ship, regardless of whether under way, anchored or moored. This category does not include ships striking underwater wrecks.

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

The Master and all deck 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 as a means of early detection of risk of collision. 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 in accordance with the applicable Collision Regulations and then confirm that such action is having the desired effect.

Full use is to be made of radar and ARPA in assessing if 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 OOW 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 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 to. Key factors to take into account are visibility, traffic density and vessel manoeuvrability.

It can be seen therefore that in order 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 it is the duty of the Master 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. Whilst these craft have the ability to manoeuvre quickly they are still required to comply with the Collision Regulations. Accordingly the Master and/or OOW on a conventional ship sighting a high speed craft must never assume because of the additional manoeuvrability that these craft 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. Wherever possible 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 vessels 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 hull insurers can vary from all to nothing with the balance usually being covered by the P&I club. The P&I club will usually also cover 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 potential scale of the club’s liabilities, it will usually take the lead role in dealing with a serious collision.



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