A question that I recently received from a reader suggested to me a topic for this month’s article. Readers may have heard that you are not allowed to tack “too close”. This leads to the question of what is too close. There is actually a full sequence of rules involved in the situation in the following diagram.
At position 1, Red and Green are on opposite tacks with Red on port tack required to keep clear of Green on starboard tack according to rule 10. This continues through positions 2 and 3.
10 ON OPPOSITE TACKS
When boats are on opposite tacks, a port-tack boat shall keep clear of a starboard-tack boat.
At position 4, Blue starts to luff – some might say in simple English that she has started to tack. Tacking however, is covered in rule 13 and the rule makes it clear that tacking doesn’t start until Red crosses head to wind. At position 4, Red is still a port-tack boat and must keep clear of Green on starboard. At position 5, though, Red has passed head to wind and is now a “tacking boat”; according to rule 13, she must keep clear of Green.
13 WHILE TACKING
After a boat passes head to wind, she shall keep clear of other boats until she is on a close-hauled course. During that time rules 10, 11and 12 do not apply. If two boats are subject to this rule at the same time, the one on the other’s port side or the one astern shall keep clear.
At position 6, Red has reached a close-hauled course. The significant fact is Red’s close-hauled course , not whether she has pulled in her sheets – she might still have her sails luffing, but she is on a course to sail close-hauled. At this point, she is still clear ahead of Green. Red is much slower after her tack, though, so Green starts to catch up. Note though that once Red is on a close-hauled course, clear ahead on the same tack as Green, rule 12 now applies and Green, who is clear astern, must now keep clear of Red.
12 ON THE SAME TACK, NOT OVERLAPPED
When boats are on the same tack and not overlapped, a boat clear astern shall keep clear of a boat clear ahead.
At position 7, Green realizes that she is going to collide with Red so she heads up and at position 8 has luffed to avoid her. The boats are now overlapped. Red is the leeward boat, so Green must keep clear of her, which she does.
11 ON THE SAME TACK, OVERLAPPED
When boats are on the same tack and overlapped, a windward boat shall keep clear of a leeward boat.
The right-of-way between the two boats changed when Red reached a close-hauled course; she changed from being the tacking give-way boat (rule 13) to being the clear-ahead right-of-way boat (rule 12). Rule 15 says that when a boat gains right-of-way she must initially give the other boat room to keep clear. Green’s luff keeps her clear so it is obvious that she was given adequate opportunity.
15 ACQUIRING RIGHT OF WAY
When a boat acquires right of way, she shall initially give the other boat room to keep clear, unless she acquires right of way because of the other boat’s actions.
In the second diagram, Blue is not as far ahead. Blue starts luffing at position 4. She is tacking at position 5 and has completed her tack at position 6. This is a bit too late, as Yellow is already having to alter course to avoid her before she achieves a close-hauled course. Blue has broken either rule 13 or rule 15 here.
The key difference between the two situations is when the boat that is not tacking has to alter course. If that boat (Yellow or Green) has to alter course before she becomes the give-way boat then the other boat has tacked “too close”. If she only has to alter course after the tacking boat has got to a close-hauled course then the tacking boat tacked “close”, but not “too close”.
© Copyright 2014 Andrew Alberti