CASE 43 Rule 10, On Opposite Tacks
Rule 18.1(b), Rounding and Passing Marks and
Obstructions: When This Rule Applies
A close-hauled port-tack boat that is sailing parallel and close to a continuing
obstruction must keep clear of a boat that has completed her tack to starboard
and is approaching on a collision course.
Question
P is sailing up-river, close-hauled on port tack, very close to the bank. S,
unable to point as high as P, is forced to sail away from the bank. She then
tacks onto starboard and immediately hails ‘Starboard’ to P. P sails on and,
when she reaches a position at which she cannot luff without hitting the bank
or bear away without colliding with S, she hails S for room. What rule or rules
apply?
Answer
P is subject to rule 10 and must keep clear. S establishes right of way over
P when she tacks onto starboard, but must observe rules 13 and 15. S meets rule
13’s requirement by not tacking so close that P has to take avoiding action
before S reaches her close-hauled course, and she meets rule 15’s requirements
by initially leaving P room to keep clear when S gains right of way. Rule 18.1(b)
makes rule 18 inapplicable.
RYA 1978/5