Animated Quiz W2
CONCLUSIONS AND RULES THAT APPLY
Red was subject to Rule 18.3 after tacking in the zone. She fulfilled these obligations by giving Green room to pass between the mark and herself. (See Rule 18.3). Green’s protest is disallowed.
Green established her overlap from astern and to leeward and therefore she cannot sail above her proper course while she remains overlapped within two of her hull lengths, on the same tack (Rule 17). When Green luffed sharply, she broke Rules 16.1 and 17, and she is disqualified under both rules.
Tactically Red behaved exactly as required. Although she could have tacked right in front Green on the layline, she would have been subject to rule 13 (need to keep clear while tacking) and Rule 18.3 (Tacking in the Zone).
Her mistake (to the extent she made one) was holding on to her previous starboard tack a little too long. Had she come across on port a couple of lengths further from the mark so that her tack could be completed outside the zone, she could have taken full advantage of her lead on Green and perhaps even driven her back a little further.
Note that the luffing situation would change dramatically if Red had crossed Green by only a small margin and the overlap between the two boats was created by Red’s act of tacking rather than by Green overtaking her to leeward. If this were the case, Rule 17 would not apply (see the 2nd sentence of Rule 17) and Green would be free to luff if she stayed within the constraints of Rule 16.1.
13. WHILE TACKING
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.
16. CHANGING COURSE
16.1 When a right-of-way boat changes course, she shall give the other boat room to keep clear.
17. ON THE SAME TACK; PROPER COURSE
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 while they remain on the same tack and overlapped within that distance, unless in doing so she promptly sails astern of the other boat. This rule does not apply if the overlap begins while the windward boat is required by rule 13 to keep clear.
18 Mark Room
18.3 Tacking in the Zone If a boat in the zone of a mark to be left to port passes head to wind from port to starboard tack and is then fetching the mark, she shall not cause a boat that has been on starboard tack since entering the zone to sail above close-hauled to avoid contact and she shall give mark-room if that boat becomes overlapped inside her. When this rule applies between boats, rule 18.2 does not apply between them.