Y and B are sailing on port tack on a windward leg. B tacks onto starboard close to Y. When B completes her tack onto starboard, both boats immediately have to luff and tack away to avoid contact. Y protests. What should the call be?

No penalty. Neither boat breaks a rule. At position 3 B acquires right of way through her own actions and must initially give Y room to keep clear. By

tacking back onto port, she gives Y room to keep clear.

If Y has to take avoiding action before B completes her tack, B breaks rule 13.

If at position 4 the boats are so close that there is risk of contact, or Y had to tack in an unseamanlike way, then B breaks rule 15.

A boat acquiring right of way may comply with rule 15 by altering course herself. This principle applies on any leg of the course.