A closehauled boat on starboard tack (S) was fetching the windward mark on the starboard-tack layline. A boat on port tack (P) crossed just ahead of S and tacked right in front of her. When P completed her tack (i.e. she reached a closehauled course), she was clear ahead of S and almost three lengths from the mark. However, S was going faster, and soon after P entered the two-length zone, S established a leeward overlap. At that point, S began to luff slowly in order to round the mark, being sure to give P room to keep clear. "You are not entitled to room at the mark," yelled P. "I am the leeward boat and you must keep clear," answered S. P luffed at first to avoid contact, but then settled on a course that did not give S enough room to pass the mark. While S was bearing off below the mark, both boats hailed "Protest" and displayed red flags. As a member of the jury, how would you rule on this incident?
Correct Answer: Penalize S
The correct answer is B) Penalize S. While P was on port tack and tacking, she was required to keep clear of S, which she did. When P completed her tack, she gained the right of way because she was clear ahead of S. Since P completed her tack outside the zone, rule 18.3 (Tacking at a Mark) did not apply.
Once P reached the zone, rule 18 (Mark-Room) applied. Since P was clear ahead of S when she (P) reached the zone, the relevant part of rule 18 is 18.2(b), which says, "If a boat is clear ahead when she reaches the zone, the boat clear astern at that moment shall thereafter give her mark-room."
Therefore, S was required to give P mark-room as long as rule 18 applied. When S established her inside overlap later on, she was not entitled to room. Since P had to luff to keep clear of S and was unable to sail her course to and around the mark, S did not give her mark-room. Therefore, S broke rule 18,2b.
P luffed and kep clear of S under rule 11 (Windward - Leeward), but even if P hadn't done this she would have been exonerated under rule 18.5 (Exoneration).