(i) acting in plenty of time. People often have about the same tolerance of how close they will get to another craft, it you wait to the last moment, you may turn at the same moment at the other vessel-sometimes with disastrous consequences!
(ii) make it very obvious to the other vessel what you have done. Usually a positive alteration of course is ideal but a large reduction in speed may be obvious to the other vessel.
At night the best tactic is to turn the vessel sufficiently that the other vessel sees the lights change colour.
Part (f) (iii)implies that if a vessel which should not impede the passage of another vessel has not done so in sufficient time to avoid a collision, the vessel which is not to be impeded is required to comply with the other rules of Part B (Rules 4 to 19) of these Rules.
Part (f) (ii) of this Rule says that a vessel which should not impede the passage of another is not relieved of that obligation if she has got so close, that the vessel not to be impeded has to take avoiding action. In any case it would be a foolish yacht skipper who expected a large vessel to be able to take sufficient avoiding action in any of the above circumstances.
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