CASE 59

Rule 18.2(a), Rounding and Passing Marks and Obstructions: Giving Room; Keeping Clear: Overlapped — Basic Rule

When a boat comes abreast of a mark but is outside the twolength zone, and when her change of course towards the mark results in a boat previously clear astern becoming overlapped inside her, rule 18.2(a) requires her to give room to that boat, whether or not her distance from the mark was caused by giving room to other boats overlapped inside her.

Question
Five boats are approaching a leeward mark dead before the wind. Four of them are overlapped in line with A nearest the mark. The fifth boat, E, is clear astern of A, B, C and D when A and B reach the two-length zone. When the four front boats come abreast of the mark and turn to round it, the change of bearing of C and D, relative to E, results in E becoming overlapped inside them while each is outside the two-length zone. E rounds the mark behind A and B but inside C and D, both of which are able to give room to E.

Is E entitled to room under rule 18.2(a) from C and D?

Answer
Since E is clear astern of A and B when they reach the two-length zone, she is required by rule 18.2(c) to keep clear of them. Between E and the two outside boats, however, a different relationship develops. C and D, in order to leave room for the two inside boats with their booms fully extended, must approach the mark on courses that bring them abreast of it outside the two-length zone. When C and D change course towards the mark, E obtains an inside overlap while they are outside the two-length zone. Thus, the conditions of rule 18.2(a) are met, and E is entitled to room under that rule, which C and D are able to give.

USSA 1982/250