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Lesson Learned

Tacking at the Windward Mark



In the figure below John is approaching the Windward Mark on the Layline fetching the mark. Steve is ahead on Port Tack. Steve can not tack to starboard and then ask for room if he completes his tack (Rules 10 and 13) inside the two boat length circle.  (Rule 18.3 Tacking at a Mark.).  Steve must complete his tack outside the 2 boat length circle.




In the figure below John is approaching the Windward Mark above the Layline reaching for the mark.  Steve is ahead on Port Tack. Steve can tack to starboard and the ask for room, if Steve can complete his tack before interfering with John and not force John above a close hauled course.  (Rule 18.3 Tacking at a Mark.) The difference is that John is not close hauled.




If you are not strapped in tight you you may have some problems with Port Tackers.. 

John habitually over stands the Layline (like most of us) and thus has a few problems, so consider the below -

First Issue - Can the Steve complete his/her tack before John has  to take action.. If not,  John has been fouled under Rule 10 and Rule 13. Further discussion is irrelevant.

Second Issue - After the Steve has completed his/her tack, does John  have to go above close hauled to avoid contact,  If so, then John have been fouled under Rule 18.3.

Otherwise, Steve is free and clear of any fouls.

Defense.  If you find yourself way above the Layline, don't reach directly for the Mark.  Reach down to the Layline and then  proceed to the Mark close hauled on the Layline. 

Recommendation.  Do not over stand the Layline..

Good Luck with the Protest Committee.


  Relevant Rules


When boats are on opposite tacks, a port-tack boat shall keep clear of a starboard-tack boat


After a boat passes head to wind, she shall keep clear of other boats until she is on a close-hauled course. During that time rules 10, 11 and 12 do not apply. If two boats are subject to this rule at the same time, the one on the other’s port side or the one astern shall keep clear.


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 actions.  

18.2 Giving Room; Keeping Clear


When boats are overlapped the outside boat shall give the inside boat room to round or pass the mark or obstruction, and if the inside boat has right of way the outside boat shall also keep clear. Other parts of rule 18 contain exceptions to this rule.


If boats were overlapped before either of them reached the two length zone and the overlap is broken after one of them has reached it, the boat that was on the outside shall continue to give the other boat room. If the outside boat becomes clear astern or overlapped inside the other boat, she is not entitled to room and shall keep clear.


If a boat was clear ahead at the time she reached the two-length zone, the boat clear astern shall thereafter keep clear. If the boat clear astern becomes overlapped outside the other boat, she shall also give the inside boat room. If the boat clear astern becomes overlapped inside the other boat, she is not entitled to room. If the boat that was clear ahead passes head to wind, rule 18.2(c) no longer applies and remains inapplicable.


When after the starting signal rule 18 applies between two boats and the right-of-way boat is changing course to round or pass a mark, rule 16 does not apply between her and the other boat.


If there is reasonable doubt that a boat obtained or broke an overlap in time, it shall be presumed that she did not. If the outside boat is unable to give room when an overlap begins, rules 18.2(a) and 18.2(b) do not apply.

18.3 Tacking at a Mark

If two boats were approaching a mark on opposite tacks and one of them completes a tack in the two-length zone when the other is fetching the mark, Rule 18.2 does not apply. The boat that tacked

(a) shall not cause the other boat to sail above close-hauled to avoid her or prevent the other boat from passing the mark, and

(b) shall give room if the other boat becomes overlapped inside her, in which case Rule 15 does not apply.


Written by John Clark.  Any comments? Send me an email

Lessons Learned

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