Clear ahead at the zone
The situation
Running down to the leeward mark, Green is clear ahead of Blue as the first of them reaches the three-length zone. Blue then lunges for the inside at the last second.
The question
Who is entitled to room, and does Blue's late inside dive earn anything?
The ruling
Green is entitled. When the boats are not overlapped as the first of them reaches the zone, the boat that hasn't reached the zone — the one clear astern — must give the other mark-room (rule 18.2(a)(2)); mark-room isn't only for an inside overlap. Blue can't manufacture an inside overlap inside the zone and demand room; she keeps clear and rounds behind. Watch the animation: Green takes her room and Blue's late dive gets nothing.
Clear ahead at the zone gets mark-room from the boat behind — a late dive inside earns nothing (rule 18.2(a)(2)).
Opens the situation on the boat-length grid — scrub it and see exactly how the boats meet. Free, no account needed.
Rules cited
See the underlying rule: Rule 18.2 — Mark-Room — Clear Ahead at the Zone.
Related cases
- Overlap obtained too late · Leeward Mark
Blue is clear astern as Green reaches the zone, then ranges up and gets an inside overlap once they're already inside the zone, and calls for room.
- The overlap breaks before the mark · Leeward Mark
Blue is the outside overlapped boat as they reach the zone, so she owes Green mark-room. Then Blue drops back and the overlap breaks before they get to the mark.
- Inside overlap at the leeward mark · Leeward Mark
Two boats run down to the leeward mark on the same tack. As the first of them reaches the three-length zone, Green is the inside overlapped boat (closer to the mark) and Blue is outside.
- Which gate mark? · Leeward Mark
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