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  3. Rule 18.2

Part 2 — When Boats Meet

Section C — At Marks And Obstructions

Section C rules do not apply between boats when the mark or obstruction referred to in those rules is a starting mark surrounded by navigable water or its anchor line, from the time the boats are approaching it to start until they have left it astern.

18.2

Giving Mark-Room

(a) When the first of two boats reaches the zone, (1) if the boats are overlapped, the outside boat at that moment shall give the inside boat mark-room; (2) if the boats are not overlapped, the boat that has not reached the zone at that moment shall give the other boat mark-room. When a boat is required to give mark-room by this rule, she shall continue to do so for as long as this rule applies, even if later an overlap is broken or a new overlap begins. (b) Rule 18.2(a) no longer applies if the boat entitled to mark-room passes head to wind or leaves the zone. (c) When rule 18.2(a) does not apply and the boats are overlapped, the outside boat shall give the inside boat mark-room. (d) If a boat obtained an inside overlap from clear astern or by tacking to windward of the other boat and, from the time the overlap began, the outside boat has been unable to give mark-room, rules 18.2(a) and 18.2(c) do not apply between them. (e) If there is reasonable doubt that a boat obtained or broke an overlap in time, it shall be presumed that she did not.

Definitions in Context

Mark-Room

Room for a boat

  • (a) to sail to the mark when her proper course is to sail close to it,
  • (b) to round or pass the mark on the required side, and
  • (c) to leave it astern.

Related Cases

Case 2

This case covers a situation involving two boats at a downwind mark in which a boat clear astern reaches the zone before a boat clear ahead. In that situation the boat clear ahead is required by rule 18.2(a)(2) to give mark-room to the boat clear astern.

Case 12

In determining the right of an inside boat to mark-room under rule 18.2(a)(1), it is irrelevant that boats are on widely differing courses, provided that an overlap exists when the first of them reaches the zone.

Case 15

In tacking to round a mark, a boat clear ahead must comply with rule 13; a boat clear astern is entitled to hold her course and thereby prevent the other from tacking.

Case 25

After an inside overlapped windward boat has been given mark-room, rule 18 no longer applies, but rule 11 continues to apply. The inside windward boat must keep clear of the outside leeward boat, and the leeward boat may luff provided that she gives the windward boat room to keep clear.

Case 59

When a boat comes abeam of a mark but is outside the zone, and when her change of course towards the mark results in a boat that is in the zone and that was previously clear astern becoming overlapped inside her, rule 18.2(a)(2) requires her to give mark- room to that boat, whether or not her distance from the mark was caused by giving mark-room to other boats overlapped inside her.

Case 63

At a mark, when space is made available to a boat that is not entitled to it, she may, at her own risk, take advantage of the space.

Rule 18.1

(a) Rule 18 applies between boats when they are required to leave a mark on the same side and at least one of them is in the zone . However, it does not apply -...

Rule 18.3

If a boat passes head to wind from port to starboard tack in the zone of a mark to be left to port, rule 18.2 does not apply between her and another boat on sta...

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