This month, I will continue with updates in the rules about Mark-Room.
(click on the diagram to see a larger cleaner version)
In the diagram, when Yellow gets to the three-length zone (position 1) she is clear ahead of Blue. According to rule 18.2(b), which has not changed, Blue as the boat clear astern must give Yellow mark-room. Blue is going a little faster so tries to go into the gap that appears to be there. At position 2, she becomes overlapped. At position 4, Yellow is at the mark and would like to bear off to round the mark. That is the course that she would have sailed if Blue was not there. This makes it Yellow’s proper course. According to the new 18.2(c)(2), Blue must give Yellow room to sail her proper course while they are still overlapped (which they are). Blue is not doing this so she breaks this rule. As the windward boat, Yellow is the give-way boat, but she is exonerated for breaking rule 11 (which is a rule of Section A) using rule 21 since Blue failed to give her mark-room. Rule 21 is very similar to the older rule 18.5 but it now covers rule 18 (mark-room), rule 19 (obstruction room) and rule 20 (room to tack at an obstruction).
18.2 Giving Mark-Room
(a) When boats are overlapped the outside boat shall give the inside boat mark-room, unless rule 18.2(b) applies.
(b) If boats are overlapped when the first of them reaches the zone, the outside boat at that moment shall thereafter give the inside boat mark-room. If a boat is clear ahead when she reaches the zone, the boat clear astern at that moment shall thereafter give her mark-room.
(c) When a boat is required to give mark-room by rule 18.2(b),
(1) she shall continue to do so even if later an overlap is broken or a new overlap begins;
(2) if she becomes overlapped inside the boat entitled to mark-room, she shall also give that boat room to sail her proper course while they remain overlapped.
However, if the boat entitled to mark-room passes head to wind or leaves the zone, rule 18.2(b) ceases to apply.
18.5 21 EXONERATION
When a boat is taking sailing within the room or mark-room to which she is entitled under a rule of Section C, she shall be exonerated if, in an incident with a boat required to give her that room or mark-room, if, as a result of the other boat failing to give her mark-room,
(a) she breaks a rule of Section A, if, by rounding the mark on her proper course, rule 15 or rule 16, or
(b) she is compelled to break rule 31.
(click on the diagram to see a larger cleaner version)
In the second diagram, Green gets to the three-length zone clear ahead of Red. Red must give Green mark-room. Red is going just slightly quicker than Green. Green for some reason (maybe trying to trap Red) stays fairly high of the mark. At position 4, Red becomes overlapped inside Green. Red must give Green room to sail her proper course. At position 4, Green’s proper course is probably to sail to the next mark. She decides to shut Red out, however, by turning at position 5 onto a course below what is probably her proper course. If at position 3, Green had borne off and sailed directly to the course to round the mark, she would have been sailing her proper course. Red is required to give her room to sail her proper course, so Green would have been exonerated for breaking the windward-leeward rule (rule 11). At position 4, when she heads down to position 5, she is not sailing her proper course, so she is not taking the room she is entitled to in rule 18.2 (b), so she will not be exonerated. The lesson is, if as the windward clear-ahead boat you want to shut out the clear-astern leeward boat, you have to do it early.
© Copyright 2013 Andrew Alberti