(pillow)Case of the week (23) - 92

(This is an installment in a series of blogposts about the ISAF Call book 2009-2012 with amendments for 2010. All calls are official interpretations by the ISAF committees on how the Racing Rules of Sailing should be used or interpreted. The calls are copied from the Call book, only the comments are written by me.)

CASE 92

Rule 14, Avoiding Contact
Rule 16.1, Changing Course
Rule 16.2, Changing Course

When a right-of-way boat changes course, the keep-clear boat is required to act only in response to what the right-of-way boat is doing at the time, not what the right-of-way boat might do subsequently.

Summary of the Facts
 
On a windward leg in winds of 18 knots, S and P approached each other on opposite tacks. P bore off to avoid S. S also bore off, and P continued bearing off in order to pass astern of S. S also continued to bear off, heeling further to leeward as a result. There was contact between the masts and rigging of the two boats and P’s mast was broken.

The protest committee disqualified S for breaking rule 16 and she appealed.


Decision

S’s appeal is dismissed. The protest committee’s decision to disqualify her is upheld, under rules 14, 16.1 and 16.2.

Initially the boats were on collision courses. P bore away to keep clear of S as required by rule 10. The written facts and the diagram established that P would have kept clear of S by passing astern of her if S had not changed her course. However, S bore away, causing P to immediately bear away still further to be able to continue keeping clear.

By changing course as she did, S broke rule 16.2. S continued changing course, at an increasing rate of turn. At some time before the collision, nothing that P could have done in a seamanlike way would have made it possible for her to keep clear. Therefore, by continuing to change course S also broke rule 16.1. In addition, S broke rule 14 and must be penalized under that rule because, as the right-of-way boat, she failed to avoid contact that caused damage.

S argued that P could have tacked or gybed, and claimed that this was P’s obligation. This is a misunderstanding of the obligations of a keep-clear boat under rule 10 and other right-of-way rules. A keep-clear boat is required to act only in response to what a right-of-way boat is doing at the time, not what the right-of-way boat might do subsequently. Until she was unable to do so, P did as she was required, keeping clear by changing course in such a way that S, had she not continued to bear away towards P, would have had ‘no need to take avoiding action’ (see the definition Keep Clear).

In failing to keep clear, P broke rule 10, but that was a consequence of S’s breaches of rules 16.1 and 16.2. Therefore P is exonerated under rule 64.1(c).

USSA 1997/75



This one is also in the Match Race Call Book under UMP 14.