When two boats are running on opposite tacks, the starboard-tack boat may
change course provided she gives the port-tack boat room to keep clear.
Assumed Facts
After sailing alongside P for some time on port tack, S gybes to starboard
tack without breaking rule 15. Both boats continue to sail parallel courses.
About two minutes after her gybe S begins to luff. P does not respond
to the luff and the boats touch at position 3. There is no damage or injury.
Questions
At the time of the contact, does rule 15 still apply? Does S break rule
16?
Answer
S as the starboard-tack boat has right of way under rule 10, and P as
the port-tack boat must keep clear. Rule 15 applies only briefly after
S becomes the right-of-way boat, but rule 16.1 continues to limit how
S may change course. S may luff provided that she does so in a way that
gives P room to keep clear, and P must be prepared to react promptly,
if necessary by gybing, to continue to keep clear. Rule 16.2 does not
apply because, although the boats are on opposite tacks, P is not sailing
to pass astern of S. Since P has room to keep clear of S by responding
promptly when S luffs, S does not break rule 16.1. P does not keep clear
and does not avoid contact with S. P therefore is to be penalized for
breaking rules 10 and 14. S also breaks rule 14 because, after it became
clear that P was not keeping clear, S could have avoided the contact.
However, because there was no damage or injury she is not to be penalized.