Rolling through to leeward
The situation
On the run, Mia catches the boat ahead and slides up to leeward of her, establishing an overlap from clear astern less than two boat-lengths away.
The question
Now that Mia is the leeward boat, can she luff the other boat up?
The ruling
She has right of way as the leeward boat (rule 11), and while she was clear astern she kept clear under rule 12. But because the overlap formed from clear astern within two hull lengths, rule 17 forbids her from sailing above her proper course while it lasts — she can't luff the windward boat up, only sail her own fastest course to the next mark. And rule 15 gave the windward boat room to keep clear at the moment the overlap formed.
Roll through to leeward and you have right of way — but rule 17 means no luffing above proper course.
Opens the situation on the boat-length grid — scrub it and see exactly how the boats meet. Free, no account needed.
Rules cited
- Rule 12 — On the Same Tack, Not Overlapped
- Rule 11 — On the Same Tack, Overlapped
- Rule 17 — On the Same Tack; Proper Course
See the underlying rule: Rule 17 — Rolling Through to Leeward (Downwind).
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