Monday, April 12, 2021

Don't Apply Part-2 Rules to the Wrong Boat

 

I’ve had a series of rules discussions with various people in the last few weeks, in which I’ve heard a common theme: They think that wording in a rule that applies to one boat in an incident somehow applies to the other boat, as well. The fact is, except for rule 14, Avoiding Contact, each numbered rule of Part 2, When Boats Meet, speaks to only one boat -- there is nothing the other boat can do, that breaks that rule.

This misunderstanding seems to happen mainly when it comes to the rules about giving room, in Sections B and C of Part 2.  For example, consider rule 18.2:

18.2 Giving Mark-Room

        (a) When boats are overlapped the outside boat shall give the inside boat mark-room, unless rule 18.2(b) applies.

        (b)  If boats are overlapped when the first of them reaches the zone, the outside boat at that moment shall
               thereafter give the inside boat mark-room. If a boat is clear ahead when she reaches the zone, the boat
               clear astern at that moment shall thereafter give her mark-room.

        (c) When a boat is required to give mark-room by rule 18.2(b),

            (1) she shall continue to do so even if later an overlap is broken or a new overlap begins;

            (2) if she becomes overlapped inside the boat entitled to mark-room, she shall also give that boat room to sail
                 her proper course while they remain overlapped.

The rule goes on from there, but (a)-(c) are the salient parts, for the purpose of this discussion.  Note that this entire rule restricts the behavior of only one boat -- the one required to give mark-room.  It does not restrict the behavior of the other boat.

Consider the following scenario (see the animation below).  Boat IW enters the zone of a leeward mark to be left to port overlapped inside boat OL.  As they approach the mark, IW sails an approach for a “wide then tight” rounding, rather than sailing directly to the mark, which is what she is entitled to room to do (see the definition Mark-Room).  OL sails alongside her while hailing “Hey!  You’re taking too much room!”  OL protests, alleging that IW broke rule 18.2(b); but the protest committee denies the protest.   

 
What was the protest committee thinking?  Well, according to rule 18.2(b), OL must give mark-room to IW; the rule says nothing about what IW might or might not do.  Put another way, there’s no rule against “taking too much room”.  So in order to be disqualified, IW would have  to break some other rule, and since she was the keep-clear boat, that means she would have to fail to keep clear under rule 11, Overlapped on the Same Tack.

This takes us to the definition of Keep Clear, which says, “A boat keeps clear of a right-of-way boat (a) if the right-of-way boat can sail her course with no need to take avoiding action, and, (b) when the boats are overlapped, if the right-of-way boat can also change course in both directions without immediately making contact.”  Did OL ever have to take avoiding action?  No; she simply sailed her course alongside IW.  Did the boats ever come close enough that OL could not change course without immediate contact?  Again, no.  So IW broke no rule.

This is sometimes referred to as “room freely given”, using the words of World Sailing Case 114, but, with apologies to the Casebook writers, I think it’s a mistake to use that expression.  I think that, to the extent possible, we should not create concepts that aren’t in the rules themselves.  The same Case could have come to the same conclusion by simply stating that the boat required to give room did so and the other boat broke no rule.

If OL wants to protest IW, she must force the issue by luffing slowly, giving IW room to keep clear of her.  If IW does not respond by changing course to sail directly to the mark, and OL has to bear off to avoid hitting her, then OL can protest IW for breaking rule 11 -- OL had to take avoiding action.  IL is not exonerated under rule 43 because she didn’t begin sailing a course directly to the mark until after position 3, when she had already broken rule 11. 

Note that if one boat's behavior is restricted under one rule and the other boat must keep clear under another rule, both rules still apply.  In particular, the keep-clear boat is not freed from her obligation to keep clear (though she will be exonerated if she sails within the room to which she is entitled).  A good example of this is rule 17, On the Same Tack; Proper Course.  That rule says that under certain conditions, when a boat establishes an overlap to leeward of another boat from clear astern she shall not sail above her proper course.  Rule 17 only refers to the proper course of the leeward boat – it says nothing about the course of the windward boat, and it does not free the windward boat of her obligation under rule 11, Overlapped on the Same Tack, to keep clear.  So, for example, if the leeward boat carries an asymmetrical spinnaker and the windward boat carries a symmetrical one, the course the windward boat will have to sail to keep clear under rule 11, Overlapped on the Same Tack, is usually going to be much higher than her proper course, even if the leeward boat obeys rule 17.  In the scenario below, Yellow could not change course to windward at position 3 without making immediate contact, so Blue breaks rule 11.



Here’s another example, from an incident a couple of weeks ago, in which a boat thought wrongly that a rule applying to her also limited the other boat.  WS and LP were sailing downwind on port tack, with WS overlapped to windward of LP (see scenario, below).  WS jibed onto starboard and the boats converged.  LP held her course until WS had to bear off to avoid contact.  Then LP jibed away and there was no further incident. 

 
LP protested WS under rule 15, Acquiring Right of Way, which says, “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.” 

The first issue here is whether WS initially gave LP room to keep clear.  In the discussion, I asked LP whether she had kept clear after WS jibed, and she replied “Yes.”  I asked her whether she had done anything unseamanlike, and she said she hadn’t.  So I asked her how she could claim WS hadn’t given her room to keep clear, when she had kept clear and in a seamanlike manner.  She said, “When WS jibed, she had to let me sail my course without taking avoiding action.  That’s what the definition of Keep Clear says.  And because I had to jibe away, she broke that rule.” 

I think she got that definition backwards.  As we saw earlier, the definition Keep Clear speaks only about the right-of-way boat taking avoiding action.  LP was, from position 3, the keep-clear boat, so the definition doesn’t say anything about whether she was needed to take avoiding action; she needed to do whatever it took, in a seamanlike way, to keep clear.

The second issue is whether LP herself broke any rules.  In my opinion, LP broke rule 11.  It’s true that LP didn’t have to begin to take action until position 2 to keep clear – there’s no requirement in the rules to anticipate a change in right of way – but she does have to begin to take action immediately when WS's mainsail crosses her center-line, just before position 2.  These particular boats were about 21’ long and traveling at about 6 knots, so they would sail a boatlength every 6 seconds or so;  that means LP sailed something like 20 seconds before she jibed.  20 seconds seems to me to be a very delayed reaction. (If you don’t believe that, imagine the skipper of LP saying "Jibing!" at position 2 and count out 20 seconds while visualizing the action aboard LP as they prepared to jibe.)  So, to my mind, LP broke rule 10, On Opposite Tacks.   

There’s one additional fact in this scenario that would, I believe, have helped a protest committee decide to penalize LP: the boats were only 5 or 6 boatlengths from the finish line and WS was on the layline to the starboard end of that line (see diagram below).  One of the things judges must do in considering the evidence is to understand the tactical significance of the boats' actions; this is one reason why it’s so important for judges to have extensive racing experience.  In this case, there’s an easy explanation for LP’s failure to respond to WS’s jibe: she wanted to get to the finish line without having to jibe twice.  That’s not conclusive evidence, of course, that she didn’t respond promptly to WS’s jibe; but it would help the protest committee determine the credibility of LP’s claim that she needed all that time to prepare to jibe.



 

Friday, March 22, 2019

New TR Rapid Response Call 2019.001


World Sailing just released a Rapid Response Call for Team Racing that has a number of interesting interpretations of the rules.  Although Team Race Calls are only authoratative for team racing, they represent the thoughts of a number of rules experts*, and when calls do not involve special rules for team racing (as this RR Call does not) they frequently are useful as interpretations of the rules for fleet racing as well.

Here’s the RR Call:

WORLD SAILING RAPID RESPONSE TEAM RACING CALL 2019.001

Rule 11 On the Same Tack, Overlapped
Rule 18 Mark-Room

Question

B and Y are approaching the finishing line. Y enters the zone on port tack above the finishing mark and clear ahead of B. Y bears away towards B and gybes onto starboard tack as she passes outside the finishing mark. Y then gybes back onto port tack to windward of B and immediately luffs rapidly towards the finishing line. B holds her course and there is contact at position 4. B protests. What is the umpire call? 

Answer

Penalize B.

When Y enters the zone clear ahead of B rule 18.2(b) applies and B must thereafter give Y mark-room. However, when Y gybes onto starboard tack rule 18 no longer applies because rule 18.1(a) applies; see Case 132.

When Y gybes back onto port tack the boats are on the same tack and rule 18 applies. Y is again entitled to mark-room under rule 18.2(b) because it was not turned off by any of the conditions in 18.2(d). Her mark-room is room to leave the mark on the required side.

Y fails to keep clear of B and breaks rule 11. Because Y promptly luffed towards the finishing line, she was sailing within her entitled mark-room and is exonerated under rule 21. B was required to give mark-room to Y and did not bear away to do so. Therefore, B has failed to give mark-room and breaks rule 18.2(b).

See also Team Race Call E10 Question 4.

This call is valid until 31 December 2019.

The main motivation for this call, I think, is the interpretation that, even though Y is sailing downwind for part of the time, the boats are on a “beat to windward”.  This interpretation comes from newly rewritten Case 132, which states that, for the purpose of rule 18.1 (When Rule 18 Applies) boats are on a beat to windward if the proper course for both is close-hauled or if one or both of them have overstood the upwind laylines of a mark.  In the new RR Call, the proper course for B is close-hauled and Y has overstood the port-tack layline of the finishing mark, so according to Case 132 the boats are on a beat to windward, and according to rule 18.1, while they are on opposite tacks rule 18 does not apply to them.  During that time, it’s just port-starboard; Y has right of way over B.

The issue of whether rule 18 applies to boats on opposite tacks at a finishing mark, when one of them has overstood the mark, was widely discussed in rules forums last year.  As Case 132 was written at the time, those boats were not on a beat to windward, leading to the possibility that a boat might purposely overstand the port layline at the port-end pin, then claim mark-room from a starboard-tack boat that was beating to the finish.  World Sailing fixed this by issuing a new version of Case 132 last November.  

So rule 18 turns off at position 2 because Y and B are on opposite tacks on a beat to windward.  Fine.  But when Y jibes back onto port tack, rule 18 comes back in force.  So now, neither boat enters the zone during the current application of the rule, so we need to look at rule 18.2(a), right?

No, according to the RR Call, wrong.  Rule 18 has “memory”:  If rule 18.2(b) is in effect and rule 18 gets suspended, then comes back into effect again, the boat that was clear ahead or overlapped inside at the zone still is entitled to mark-room, unless she tacks, leaves the zone, or has been given all the mark-room to which she is entitled (see rule 18.2(d)).  (None of those exceptions applies in the RR Call scenario.) 

This is not the first time the concept of "memory" has been enunciated.  In Team Race Call E10, the boat required to give mark-room at a windward mark tacks and then tacks back into an inside overlap.  In that situation, it makes a lot of sense to re-impose rule 18.2(b); rule 18.2(d) only turns off rule 18.2(b) when the boat entitled to mark-room tacks, leaves the zone or has been granted mark-room; the other boat cannot escape her obligation to give mark-room by tacking or leaving the zone herself.  And, I suppose, once that “memory” interpretation has been made in Call E10, it must apply even in situations where the boat required to give mark-room doesn’t tack or leave the zone – as in the new RR Call.

The next question answered in the new RR Call is whether Y is sailing within the room to which she is entitled.   There are two interesting issues here.  First, the only room BB is required to grant to Y at positions 2 and 3 is room to round the mark as required to sail the course and room to leave the mark on the required side (see the definition mark-room).  Y could take that room by sailing out and around astern of B, but the RR Call asserts that when Y cuts inside B she is sailing within the room to which she is entitled.  In other words, the definition should be read in a common-sense manner and Y is entitled to carry out the rounding and passing maneuver in the natural way, inside B. 

The second issue is whether Y "takes too much room" during the scenario.  According to the text of the Question, as soon as Y jibes onto port tack she “luffs rapidly”, implying that after she jibes she takes the minimum space she needs to round inside B (the boats are keelboats, so Y’s arc seems unnecessarily wide to dinghy sailors, but the words about luffing rapidly assure us she is not taking too much room in positions 2-3).   However, if we look at her entire track since she entered the zone, she clearly takes more space than she needs to sail to the mark and round it on the required side.  The key here is she doesn’t need the protection of mark-room until she jibes back onto port tack, so before that moment she can sail where she pleases.  When Y loses her right of way just after position 2, she is entitled to the space she needs to round the mark in a seamanlike way, starting at that position.

To see a common application of this principle in another context, consider the diagram below.  Yellow enters the zone at a leeward mark clear ahead of Blue.  Because she is clear ahead, she has right of way; and in any case, Blue cannot reach her.  Until position 2  Yellow does not need to rely on her right to mark-room, so, instead of sailing to the mark she sails wide (but not wider than her proper course – see rule 18.4).  When she jibes onto port tack, she is required to keep clear of Blue, who is on starboard tack.  Blue has to take avoiding action, so according to the definition keep clear, Yellow breaks rule 10 (Port-Starboard).  


Suppose Blue protests Yellow for that infraction.  Yellow’s defense is that she was sailing within the mark-room to which she was entitled, and is therefore exonerated under rule 21 (Exoneration).  Blue argues that Yellow’s entitlement was room to sail to the mark, room to round it as necessary to sail the course, and room to pass it on the required side.  Yellow, she says, was sailing outside the room to which she was entitled in two ways.  First, she didn’t sail to the mark wen Blue gave her room to do so, and second, the definition room includes the word “promptly”; by sailing wide on her proper course instead of sailing directly to the mark, Yellow failed to carry out the mark-rounding maneuver promptly.  Therefore, Blue says, Yellow should be penalized for breaking rule 10 just before position 3.  

The protest committee should decide that when Yellow was clear ahead she was not required to approach the mark “promptly” because she had right of way.  Once she lost that right of way and thus really needed mark-room to protect her, she was then obliged to sail to the mark and round it promptly, as she did, so she is exonerated under rule 21.  And that is the principle used in coming to the conclusion in RR Call 2019.001.

*Note: I am a member of the World Sailing Team Race Rules Working Party, which edited and approved the new RR Call, but the views expressed here are my own and do not represent the views of that working party or of any of its other members.