CASE 09
Definitions, Proper Course
Rule 10, On Opposite Tacks
Rule 18.1(a), Mark-Room: When Rule 18 Applies
Rule 18.1(b), Mark-Room: When Rule 18 Applies
When a starboard-tack boat chooses to sail past a windward
mark, a port-tack boat must keep clear. There is no rule that
requires a boat to sail a proper course.
Question
Two close-hauled boats on opposite tacks meet at a windward mark to be
left to starboard. S has adequate room to tack and round the mark with due
allowance for wind and current but instead of tacking, S holds her course
with the intention of forcing P to tack to keep clear. Can P disregard rule 10
if she considers S to be sailing beyond her proper course and to have
sufficient room to round the mark?
Answer
No; rule 10 applies. Rule 18 does not apply if the boats are in any one of the
four situations described in rules 18.1(a), (b), (c) or (d). Both rule 18.1(a)
and rule 18.1(b) apply to S and P. They are on opposite tacks on a beat to
windward (see Case 132). Also the proper course for S, but not P, is to tack.
When S chooses to hold her course, P must keep clear. While in certain
circumstances boats are prohibited from sailing above a proper course there
is no rule that requires a boat to sail her proper course.
GBR 1964/2