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Day Skipper revision module 5 of 17
International Regulations for Preventing Collisions at Sea — steering rules, lights, and shapes.
9 guided lessons · 18 practice questions · 12 flashcards
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The International Regulations for Preventing Collisions at Sea are commonly called COLREGs or IRPCS. Rule 1 applies them to all vessels on the high seas and waters connected with the high...
Authority cluster
Rule 5 requires every vessel at all times to maintain a proper lookout by sight and hearing as well as by all available means appropriate to the prevailing circumstances and conditions. T...
Rule 6 first requires a safe speed that lets the vessel take proper and effective avoiding action and stop within an appropriate distance. Visibility, traffic density, manoeuvrability, ba...
Rule 8 requires avoiding action to comply with the Rules of Part B and, when circumstances admit, to be positive, made in ample time and taken with due regard to good seamanship. Alterati...
These rules sit in Section II and apply only when vessels are in sight of one another—meaning visually observable. Rule 13 is checked first because any vessel overtaking another must keep...
Except where Rules 9, 10 and 13 otherwise require, a power-driven vessel underway keeps out of the way of a vessel not under command (NUC), a vessel restricted in ability to manoeuvre (RA...
Rule 16 requires every vessel directed to keep out of the way, so far as possible, to take early and substantial action to keep well clear. The manoeuvre must meet Rule 8 and remain under...
Rule 9 requires a vessel proceeding along a narrow channel or fairway to keep as near the starboard outer limit as is safe and practicable. A vessel under 20 metres or a sailing vessel mu...
An ordinary power-driven vessel underway shows a forward masthead light, sidelights and a sternlight. A vessel 50 metres or more also shows a second masthead light abaft and higher than t...
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This independent revision material is not a substitute for current official publications, competent instruction or on-water judgement.