The leeward boat luffs
The situation
Two boats sail close-hauled side by side on the same tack, overlapped. Green is to leeward, Blue close alongside to windward. Green begins to luff, heading up toward the wind.
The question
Must Blue respond, and is there any limit on Green's luff?
The ruling
Blue (windward) must keep clear of Green (leeward) under rule 11. Green may luff, but as a right-of-way boat changing course she must give Blue room to keep clear (rule 16.1) — she can't luff so suddenly that Blue has no chance to respond. And if Green got the overlap from clear astern within two hull lengths to leeward, rule 17 stops her from sailing above her proper course.
Windward keeps clear, but a luffing leeward boat must still give room to respond — and rule 17 may cap how high she can go.
Opens the situation on the boat-length grid — scrub it and see exactly how the boats meet. Free, no account needed.
Rules cited
- Rule 11 — On the Same Tack, Overlapped
- Rule 16.1 — Changing Course
- Rule 17 — On the Same Tack; Proper Course
See the underlying rule: Rule 11 — On the Same Tack, Overlapped.