Rules Quiz
For an animated version of this situation, visit
www.ukhalsey.com, Rules Quiz 24.
The Situation
Two boats are approaching a windward mark to be left
to port.
Facts Found:
Red
Red, the leading boat, was on the starboard-tack layline.
Green was about 1/2 boatlength astern of Red and 1/2
Green
boatlengh to windward of the starboard tack layline. Red was
clear ahead when she reached the zone. The wind had shifted
approximately 10 degrees to the right as the boats neared the
windward mark, so Red decided to gybe immediately after
rounding it. Since she had been on the starboard layline,
Green
she passed close aboard the starboard side of the mark and
her turn to bear off and gybe left a space of about 3/4 of a
boatlength between herself and the mark. Green stayed to
windward of Red all the way to the mark to keep her air clear
and her intention was to bear away onto a starboard tack run.
Red
Since she passed well to windward of the mark she was able
bear away into the space left by Red. As soon as Red bore
off to a dead downwind course, she gybed onto port tack.
Green bore off to a dead run after Red gybed, but stayed
on starboard tack. When Red gybed, she was only about 1
boatlength from the mark but suddenly found herself sailing
across the bow of a starboard tack boat. Red could have gybed
back onto starboard tack to protect herself, but instead tried
to cross ahead of Green. Green hailed “Starboard” and when
it was apparent that Red would not clear her, she luffed to
avoid a collision. Green hailed “Protest” and flew her flag
Green
immediately. There was no contact although the boats came
very close and a collision would have occurred if Green had
not luffed when she did. Both boats agreed that the incident
took place close to the mark but they could not agree on the
distance because they were too busy looking at the other
boat. Green protested under Rule 10.
Red
Conclusions and Rules that apply:
Rule 18.2(b) states, “… If a boat is clear ahead when she
reaches the zone, the boat clear astern at that moment shall
thereafter give her mark-room”. The definition of Mark-
room says that it is room to sail to the mark and then room
to round it on her proper course. Because of the wind shift,
gybing is definitely a proper course for Green, so Red must
give her room to gybe. However, when Green gybed, she
became the keep-clear boat, and because the right of way
changed because of her own action she was not protected by
Green
rule 15 – Red had no obligation initially to give her room to
keep clear. Just after that, when Green bore off on Red, she
was subject to Rule 16.1 and had to give Red room to keep
clear, but because the jury determined that Red could have
gybed back onto starboard tack and thus regained right of
Red
way, Green did not break Rule 16.1. When Red failed to keep
clear, she broke Rule 10 and is disqualified.
48° No r t h , oc t o b e r 2009 Pa g e 48
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