Boat M does not hail for room to tack. Shortly after position 2, Boat I decides she can tack and fetch the mark. Just after I luffs to tack, M begins to tack. I passes head to wind shortly before M does. As the boats tack, Boat S continues to sail a close-hauled course and there is space for one boat (but not two) to pass between S and the mark. Between positions 4 and 5, I luffs to round the mark. In response to I’s luff, both M and S luff above close-hauled. There is no contact. No boat takes a Two-Turns Penalty. Both S and M protest I.

Question

How does rule 18.3 apply to this incident and what should the decision be?

Answer

The two protests were the result of a single incident, so they should be heard together.

S broke no rule. She was required by rule 11 to keep clear of M from the moment M completed her tack, and she did so.

After I and M passed head to wind, each of them was on the same tack as S who was fetching the mark, so rule 18.3(a) applied to both I and M with respect to S. When both I and M luffed between positions 4 and 5, S sailed above close-hauled to avoid contact, so both I and M broke rule 18.3(a). However, M is exonerated under rule 64.1(a) for breaking rule 18.3(a) because she was compelled to luff by I’s luff.

After I changed tack she was fetching the mark. When M changed tack she became overlapped outside I, so rule 18.3(b) applied to M. It required M to give I mark-room, including ‘space to comply with her obligations under the rules of Part 2’ (see the definitions Room and Mark-Room). When I luffed to sail to the mark, she broke rule 18.3(a). Because M did not give I space to comply with rule 18.3(a) as I sailed to the mark, M broke rule 18.3(b).

Note that I is not exonerated for her breach of rule 18.3(a). She is not exonerated under rule 64.1(a) because she was not compelled to luff between positions 4 and 5. Instead she could have borne off after position 4 and left the mark to starboard. She is not exonerated under rule 21 because rule 18.3(a) is not one of the rules listed in rule 21(a).

To sum up, I broke rule 18.3(a) by causing S to sail above close-hauled and she is not exonerated for that breach. M broke rule 18.3(b) by failing to give I mark-room and she is not exonerated for that breach. Therefore, both I and M are disqualified.