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  3. Rule 18.3

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.

18.3

Tacking in the Zone

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 starboard tack that is fetching the mark. If the other boat has been on starboard tack since entering the zone, the boat that passed head to wind

  • (a) shall not cause the other boat to sail above close-hauled to avoid contact, and
  • (b) shall give mark-room if the other boat becomes overlapped inside her.

Definitions in Context

Clear Astern and Clear Ahead; Overlap

One boat is clear astern of another when her hull and equipment in normal position are behind a line abeam from the aftermost point of the other boat’s hull and equipment in normal position. The other boat is clear ahead. They overlap when neither is clear astern. However, they also overlap when a boat between them overlaps both. These terms always apply to boats on the same tack. They apply to boats on opposite tacks only when rule 18 applies between them or when both boats are sailing more than ninety degrees from the true wind.

Fetching

A boat is fetching a mark when she is in a position to pass to windward of it and leave it on the required side without changing tack.

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.

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.
Tack, Starboard or Port

A boat is on the tack, starboard or port, corresponding to her windward side.

Zone

The area around a mark within a distance of three hull lengths of the boat nearer to it. A boat is in the zone when any part of her hull is in the zone.

Rule 18.2

(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...

Rule 18.4

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 t...

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