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  3. Rule 18.4

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.

18.4

Gybing in the Zone

When an inside overlapped right-of-way boat must gybe at a mark to sail her proper course, until she gybes she shall sail no farther from the mark than needed to sail that course. Rule 18.4 does not apply at a gate mark.

Definitions in Context

Mark

An object the sailing instructions require a boat to leave on a specified side, a race committee vessel surrounded by navigable water from which the starting or finishing line extends, and an object intentionally attached to the object or vessel. However, an anchor line is not part of the mark.

Overlap

See Clear Astern and Clear Ahead; Overlap.

Proper Course

A course a boat would choose in order to sail the course as quickly as possible in the absence of the other boats referred to in the rule using the term. A boat has no proper course before her starting signal.

Rule
  • (a) The rules in this book, including the Definitions, Race Signals, Introduction, preambles and the rules of relevant appendices, but not the Basic Principles or titles;
  • (b) World Sailing Regulations that have been designated by World Sailing as having the status of a rule and are published on the World Sailing website;
  • (c) the prescriptions of the national authority, unless they are changed by the notice of race or sailing instructions in compliance with the national authority’s prescription, if any, to rule 88.2;
  • (d) the class rules (for a boat racing under a handicap or rating system, the rules of that system are ‘class rules’);
  • (e) the notice of race;
  • (f) the sailing instructions; and
  • (g) any other documents that govern the event.

Related Cases

Case 75

When rule 18 applies, the rules of Sections A and B apply as well. When an inside overlapped right-of-way boat must gybe at a mark, she is entitled to sail her proper course until she gybes. A starboard-tack boat that changes course does not break rule 16.1 if she gives a port-tack boat adequate space to keep clear and the port-tack boat fails to take advantage of it promptly.

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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