Right of way — opposite tacks, same tack, tacking (Rules 10–13)
Four rules say who has right of way when two boats meet. Two facts decide which one applies: the tack each boat is on and whether they overlap. One boat keeps clear; the other may sail her course.
1 · Which rule applies
Tacks first, then overlap
Which racing rule applies when two boats meet: rule 10, 11, 12 or 13?
Check tacks first, then overlap: opposite tacks, rule 10 (port keeps clear); same tack overlapped, rule 11 (windward keeps clear); same tack not overlapped, rule 12 (clear astern keeps clear); past head to wind, rule 13 (tacking boat keeps clear).
Part 2 applies between boats sailing in or near the racing area that intend to race, are racing or have been racing: before the start, on every leg, until you have finished and cleared the line. Between them it replaces the collision regulations. Size, speed, class, the leg you are on and who hailed first change nothing, and a windsurfer is a boat.
Situation
Rule
Keeps clear
Opposite tacks
10
Port tack
Same tack, overlapped
11
Windward boat
Same tack, not overlapped
12
Boat clear astern
Past head to wind, not yet close-hauled
13
Tacking boat
Rule 12 exists only on the same tack. On opposite tacks rule 10 decides even when one boat is clear astern, so a gybe by the boat ahead can change who keeps clear.
2 · Rule 10 · opposite tacks
Port keeps clear of starboard
Rule 10: does port tack keep clear of starboard even when running downwind?
Yes: on opposite tacks the port-tack boat keeps clear, whether beating, reaching or running. On a run read the tack from the mainsail: boom to starboard means port tack.
On opposite tacks the port-tack boat keeps clear, whether the boats are beating, reaching or running. On a run, read the tack from the mainsail: boom to starboard means port tack. A boat luffing head to wind is still on her old tack.
On a beatport crosses, ducks or tacks
On a runboom to starboard: port tack keeps clear
The rule says who keeps clear, not how: cross ahead if you safely can, bear away astern of her, or tack. You kept clear if she could hold her course with no need to avoid you; if she had to alter, you broke the rule, contact or not. No hail is needed, and current, waves or a late duck are your problem. Starboard may still alter course, within rule 16.
On a beat rule 18 does not apply between boats on opposite tacks, so at the windward mark rule 10 stands alone. On a reach or a run starboard keeps right of way but may owe an inside port-tack boat mark-room.
3 · Rule 11 · same tack, overlapped
Windward keeps clear of leeward
Rule 11: who keeps clear when two boats on the same tack are overlapped?
The windward boat keeps clear, however the overlap began and whoever's bow is ahead. The leeward boat may sail her course and luff, limited only by rules 16.1 and 17.
On the same tack and overlapped, the windward boat keeps clear, however the overlap began and whoever's bow is ahead. On a run she is the boat on the side opposite the booms.
Overlappedwindward keeps clear: hull, boom and sails
Barging at the startno room at the committee boat
You keep clear with the whole boat, with a margin for gusts. If you cannot point higher, slow down, drop astern or tack away cleanly: the leeward boat may sail her course and may luff, limited only by rules 16.1 and 17. Before the start there is no proper course, so she may luff as far as head to wind, giving you room.
At a starting mark surrounded by navigable water there is no mark-room for boats approaching to start, so a windward boat squeezing in has no rights. With three boats abreast the rule applies to each pair; a middle boat forced onto the leeward one by a boat that did not keep clear is exonerated.
4 · Rule 12 · same tack, not overlapped
Clear astern keeps clear of clear ahead
Rule 12: on the same tack, does the boat behind keep clear of the boat ahead?
Yes: on the same tack and not overlapped, the boat clear astern keeps clear. Waves, surfing and a boat ahead that slows down are her problem; slowing down is not a change of course.
On the same tack and not overlapped, the boat clear astern keeps clear. Surfing, waves, current, a boat ahead stalled or fighting her spinnaker: all the astern boat's problem. The boat ahead may slow down, which is not a change of course, and may alter course to defend her wind if she leaves you room (rule 16.1). Taking her wind is allowed.
You pass to windwardyou keep clear all the way: rule 12, then 11
You pass to leewardonce overlapped you have right of way
Leeward and windward exist only between overlapped boats: a hail of "leeward boat" from clear astern gives you nothing. Once your bow, or a bowsprit with its sail set, overlaps her to leeward, rule 11 makes you the right-of-way boat, but you must first give her room to keep clear (rule 15) and may be limited by rule 17.
5 · Rule 13 · while tacking
No rights from head to wind to close-hauled
Rule 13: when do I lose my rights while tacking, and when do I get them back?
From passing head to wind until you are on a close-hauled course you keep clear of other boats under rule 13, and rules 10 to 12 do not apply. The rule ends with your heading, even with sails still flapping.
After you pass head to wind you keep clear of other boats until you are on a close-hauled course. During that time rules 10, 11 and 12 do not apply, and a hail of "Tacking!" gives you nothing.
Moment
What applies
Luffing, up to head to wind
The old tack: rules 10–12
Past head to wind
Rule 13: keep clear of everyone
On a close-hauled course
The new tack's rule, with rule 15
The rule ends with your heading, not your trim: sails may still be flapping, and a boat stuck in irons is tacking for as long as it takes. If two boats tack at once, the one on the other's port side, or the one astern, keeps clear. A gybe has no such rule: rules 10 to 12 apply throughout it.
Out of the tack you may hold right of way as starboard, leeward or clear ahead, but rule 15 first gives the other boat room to keep clear. In the zone of a mark to be left to port, rule 18.3 limits you further.
Practice questions
Questions from this topic, as the app asks them. Open one to see the answer.
Forty seconds before the start of a Hobie 16 race you are reaching slowly along the line on starboard tack. Green comes the other way on port tack, below the line, and you converge. Her helm says that before the start «there are no rules yet». Who keeps clear?
Green — Part 2 applies to boats sailing in the racing area well before the start, and the port-tack boat keeps clear
You — before the start the boat nearer the committee boat keeps clear
Green — but only because she is sailing away from the line
Nobody — the right-of-way rules only apply after the starting signal
Show the answer
A. Green — Part 2 applies to boats sailing in the racing area well before the start, and the port-tack boat keeps clear
Rule 10 applies before the start like any Part 2 rule: Part 2 governs boats sailing in or near the racing area.
Wednesday evening club race, first beat. You are close-hauled on port tack in a Laser; Red, also close-hauled but on starboard tack, is converging from your right and will arrive at the same spot in about five seconds. Who keeps clear?
You — a port-tack boat keeps clear of a starboard-tack boat (rule 10)
Whichever boat is to windward at the moment the courses cross
Red — you will reach the crossing point first, so you are clear ahead
Red — the boat that has the other on her left-hand side keeps clear
Show the answer
A. You — a port-tack boat keeps clear of a starboard-tack boat (rule 10)
Rule 10: when boats are on opposite tacks, the port-tack boat keeps clear of the starboard-tack boat.
First beat of a Star class regatta in Split. You and Blue are both close-hauled on starboard tack and overlapped, Blue a length to leeward of you. You are slowly sagging down towards her. Who keeps clear?
Blue — the boat that established the overlap from astern keeps clear
You — on the same tack and overlapped, the windward boat keeps clear (rule 11)
Blue — the leeward boat must bear away to give you room to sail your course
Neither — both boats hold their course until one of them is clear ahead
Show the answer
B. You — on the same tack and overlapped, the windward boat keeps clear (rule 11)
Rule 11: when boats are on the same tack and overlapped, the windward boat keeps clear of the leeward boat.
On the run of a 49er regatta in 25 knots you catch a wave and surf straight into the transom of Blue, who is sailing dead ahead of you on the same gybe. Blue did not change course. Who broke a rule?
Blue — a boat ahead must keep moving fast enough not to be hit by the boat astern
Nobody — contact caused by a wave in strong wind is not a breach
You — a boat clear astern keeps clear of a boat clear ahead on the same tack (rule 12), and you also broke rule 14
Blue — she should have gybed away when she saw you surfing down on her
Show the answer
C. You — a boat clear astern keeps clear of a boat clear ahead on the same tack (rule 12), and you also broke rule 14
Rule 12: on the same tack and not overlapped, the boat clear astern keeps clear; waves are the astern boat's problem.
You are the leeward boat on starboard and luff Grey, who is overlapped to windward and responds. You keep turning and pass head to wind. What are the rights now?
Grey must now keep clear of you under rule 10, since you are about to be on port tack
You are now tacking: you must keep clear of Grey until you are close-hauled on port tack (rule 13); rule 11 no longer applies to her
Nothing changes — you remain the leeward right-of-way boat until you are close-hauled on the new tack
Both boats must stop luffing; neither has right of way while one is head to wind
Show the answer
B. You are now tacking: you must keep clear of Grey until you are close-hauled on port tack (rule 13); rule 11 no longer applies to her
Rule 13: from passing head to wind until close-hauled the tacking boat keeps clear; rules 10–12 are switched off for her.
On the run of a windward–leeward course in 12 knots you are in a 470 on port gybe, boom out to starboard. Grey is running on starboard gybe and converging slowly from your right, two hull lengths away; no mark is near. Who keeps clear?
Grey — she is to windward of you and the windward boat keeps clear (rule 11)
You — on a run the tack is given by the side the boom is on, and you are the port-tack boat (rule 10)
Grey — on a run boats are not on tacks, so the boat astern keeps clear
Neither — on a run both boats hold their course until one is overlapped inside
Show the answer
B. You — on a run the tack is given by the side the boom is on, and you are the port-tack boat (rule 10)
Rule 10 applies on every point of sail; definition Tack: a boat is on the tack of her windward side, opposite to her boom.
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