Same-Tack Scenarios at the Start

David Norton

Several readers have written me with questions about how the rules apply between two starboard-tack boats on their final approach to the starting line to start. Such questions are relatively easy to analyze because two of the more complex rules do not apply at this time.

Rule 18.1(b) states that all of Rule 18 does not apply “at a starting mark surrounded by navigable water or at its anchor line from the time boats are approaching them to start until they have passed them.” Also, because boats do not have a proper course before the starting signal, Rule 17, which requires a boat not to sail above or below her proper course under certain circumstances, doesn’t apply. In almost all same-tack starting approach situations, the only applicable rules are Rule 11, if the boats are overlapped; Rule 12, if they are not overlapped; Rule 15, if one boat just acquired right of way through her own actions; and Rule 16.1, if the right-of-way boat changes course.

In the situations we will examine, neither boat is tacking. Therefore, Rule 13 doesn’t apply. If there’s contact, then Rule 14 must be addressed. However, when boats touch there’s invariably a rule infringement before the contact because at some point they must get so close to one another that the right-of-way boat “needs to take avoiding action.” At that moment, which is always before contact occurs, the other boat fails to keep clear (see the definition Keep Clear).


The Rules That Apply

Rule 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.

Rule 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.


Rule 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.

Rule 16.1 Changing Course: When a right-of-way boat changes course, she shall give the other boat room to keep clear.

Barging Situations


Denys Allain and Angelo Guarino asked questions about the simple situation shown in Diagram 1. The starting line slightly favors the starboard end. Lou and Wendy are overlapped throughout their approach to the committee boat, which is the starboard-end mark. Lou is sailing close-hauled and, if he holds his course, will pass just to leeward of the committee boat’s stern and there will not be room for Wendy to pass between him and the mark.

Denys points out that the committee boat is big enough to qualify as an obstruction and wonders if, for that reason, Wendy can invoke Rule 18.2(a) and request room from Lou to pass the committee boat. The answer is “No.” Rule 18 does not apply at any starting mark surrounded by navigable water, whether or not the mark is also an obstruction.

As long as Lou holds his course, the only applicable rule in this situation is Rule 11. It requires Wendy, the windward boat, to keep clear. If Wendy continues to converge with Lou, there will come a time when Lou needs to take avoiding action. At that moment Wendy breaks Rule 11.


Also, at that same time, Rule 14 begins to apply to Lou. It obligates him to avoid contact with Wendy if “reasonably possible” However, whether or not Lou avoids contact in no way changes the fact that Wendy has broken Rule 11, and, if there is contact, Lou can be penalized only if the contact causes damage.

Note that, at position 2, it would be easy for Wendy to luff and pass the committee boat to port and avoid a confrontation with Lou. If she holds her course until position 3, she can no longer escape, but that does not relieve her of her obligation to keep clear of Lou.

Look at Diagram 2. This differs from the first situation because Lou’s approach to the committee boat is on a track slightlyto leeward of his line of approach in Diagram 1. Now the question is, “Is Lou allowed to luff in order to deprive Wendy of room to pass to leeward of the committee boat?”

Lou holds right of way under Rule 11. If Lou changes course, Rule 16.1 requires him to give Wendy “room to keep clear.” A luff by Lou at position 2 does not break Rule 16.1 because at that time there’s plenty of space for Wendy to keep clear. However, if Lou begins to luff when the boats are in position 3, then he does break that rule because there is no longer space for Wendy to maneuver to keep clear without hitting the committee boat, which is clearly not a seamanlike action.

To summarize–a leeward boat may always hold her course as she approaches a starting mark and, if there is not room for a barging windward boat to pass to leeward of the mark, then that’s just tough for the barger. However, a leeward boat may not luff to deprive a barging boat of room unless at the time she luffs there’s room for the barger to keep clear.

Mid-line windward-leeward encounters

Jeff Cohen asks about four different situations that often crop up when one of two boats is trying to avoid going over the line before the starting signal. These are shown in Diagrams 3 to 6. In each one Andy converges with Barb as he tries to avoid crossing the line too soon. Jeff asks which rules apply and what the obligations of the two boats are in each of the scenarios.

Diagram 3. At position 1 Rule 12 gives Andy right of way as the clear-ahead boat. Andy’s bears away and that action creates an overlap. When the overlap begins, Rule 12 no longer applies and Barb acquires right of way under Rule 11 as the leeward boat. Because it is Andy’s action that creates the overlap, Rule 15 does not apply. At position 2 Andy breaks Rule 11 by failing to keep clear. Barb holds her course while the boats are overlapped, and so Rule 16.1 never applies to her.

Diagram 4. At all times Rule 12 gives Andy right of way because he is clear ahead. Between position 1 and 2, as Andy bears away, he is required by Rule 16.1 to give Barb room to keep clear. Barb luffs slightly after position 2 and avoids contact. Neither boat breaks a rule. Barb keeps clear as required by Rule 12, and Andy gives her room to do so as required by Rule 16.1.

Diagram 5. The boats are overlapped at all times. Rule 11 gives Barb right of way as the leeward boat. Because Barb holds her course, Rule 16.1 does not apply. At position 2 Andy is breaking Rule 11 because he is not keeping clear.

Diagram 6. As in the last scenario, the boats are overlapped and Barb holds right of way under Rule 11 throughout the incident. As she luffs Rule 16.1 requires Barb to give Andy room to keep clear. Moreover, no rule prevents Barb from luffing Andy across the line. There is obviously plenty of room for Andy to keepclear. He fails to respond promptly when Barb luffs and, as a result, breaks Rule 11 at position 2.

In order to avoid any problem with Rule 14, in each of the situations shown in Diagrams 3, 5 and 6 Barb should try to avoid contact as soon as it becomes clear to her that Andy is not going to keep clear.

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