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Rule 16

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Rule 16: CHANGING COURSE | Protest Room

Part 2 — When Boats Meet

Section B — General Limitations

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16

CHANGING COURSE

16.1:

When a right-of-way boat changes course, she shall give the other boat room to keep clear.

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16.2:

In addition, on a beat to windward when a port-tack boat is keeping clear by sailing to pass to leeward of a starboard-tack boat, the starboard-tack boat shall not bear away if as a result the port-tack boat must change course immediately to continue keeping clear.

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Related Cases & Q&A

A starboard-tack boat that tacks after a port-tack boat has borne away to go astern of her does not necessarily break a rule .

When, after having been clear astern , a boat becomes overlapped to leeward within two of her hull lengths of the other boat, the windward boat must keep clear , but the leeward boat must initially give the windward boat room to keep clear and must not sail above her proper course . The proper course of the windward boat is not relevant.

Before her starting signal, a leeward boat does not break a rule by sailing a course higher than the windward boat’s course.

When, because of a difference of opinion about a leeward boat’s proper course , two boats on the same tack converge, the windward boat must keep clear . Two boats on the same leg sailing near one another may have different proper courses .

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 .

A right-of-way boat need not act to avoid a collision until it is clear that the other boat is not keeping clear . However, if the right-of-way boat could then have avoided the collision and the collision resulted in damage, she must be penalized for breaking rule 14 .

A leeward boat is entitled to luff to her proper course , even when she has established a leeward overlap from clear astern and within two of her hull lengths of the windward boat.

Rule 16.1 does not restrict the course of a keep-clear boat. Manoeuvering to drive another boat away from the starting line does not necessarily break this rule.

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.

When a right-of-way boat changes course, the keep-clear boat is required to act only in response to what the right-of-way boat is doing at the time; she is not required to anticipate what the right-of-way boat might do subsequently.

If a boat luffs immediately after she becomes overlapped to leeward of another boat and there is no seamanlike action that would enable the other boat to keep clear, the boat that luffs breaks rules 15 and 16.1 . The other boat breaks rule 11 , but is exonerated.

When two boats are running on opposite tacks, the starboard-tack boat may change course provided she gives the port-tack boat room to keep clear.

When a boat is entitled to room , the space she is entitled to includes space for her to comply with her obligations under the rules of Part 2 and rule 31 .

When boats are approaching a starting mark to start and a leeward boat luffs, the windward boat is exonerated by rule 43.1(b) if she breaks rule 11 while sailing within the room to which she is entitled under rule 16.1 .

Interpretation of the phrase ‘on a beat to windward’.

When a right-of-way boat changes course, her obligation to give a keep-clear boat room to keep clear under rule 16.1 begins. The right-of-way boat may give that room by making an additional change of course. If, while the right-of-way boat is making that additional change of course, the keep-clear boat unavoidably breaks a rule of Part 2 Section A, the keep-clear boat is exonerated by rule 43.1(b) .

Tacking in the Zone

Definition of Mark-Room

Rule 15

When a boat acquires right of way, she shall initially give the other boat room to keep clear , unless she acquires right of way because of the other boat’s act...

Rule 17

If a boat clear astern becomes overlapped within two of her hull lengths to leeward of a boat on the same tack , she shall not sail above her proper course whil...