Minor editorial correction, boat name Amy changed to Zoe in two locations, the fourth paragraph above the first illustration, and twice in the second to last paragraph.

Thank you for spotting my error Dan! 

Corrected now. 

Born "It is not obvious what right the boat with mark room has to alter course above proper corse in the mark rounding."

Perhaps the better question that you might care to address is:  "What rule, for which she is not exonerated, is it alleged that Amy breaks?"

Case 63 does not say that the outside boat is not exonerated for breaking RRS 16.1 If she is sailing other than her proper course.

One point - Europe class does not have spinnaker
The diagram is somewhat confusing. If you follow the diagram Amy enters the zone but does not sail to the mark. As she is sailing outside  the room to which she is entitled then RRS 43.1(b) does not apply.
If however Amy enters the zone and  sails to a point 1m from the mark, then she IS sailing within her mark room. When Amy luffs to round the mark she is also sailing within her mark room and is exonerated fro a breach of RRS 16 but not 14 under RRS 43.1(b). However, if the PC finds that she broke RRS14 then she can be exonerated under RRS 43.1(c) if there is no damage or injury.

Thank you Gordon for your thoughts!

The question is if Amy is being exonerated under 43.1b when she luffs Above proper course in the markroundning in an attempt to shut the door on Ben.

If Amy sails her proper course the answer is clear that she will be exonerated. See 18.2 c 2.

Interesting point regarding the mark room and taking more mark room than Amy is entitled to. Amy choose to sail her proper course to the mark. This is the way I think most sailors would sail to the mark in this situation. There is no overlap to begin with, so she has both right of way and mark room. Then when there is an overlap and she has still both right of way and overlap. In my interpretation she can sail her proper course to the mark when having both right of way and mark room during the whole mark rounding, not only room to sail to the mark.
 
No, Europe have no spinnaker, but I was hoping with the illustration to make the situation more easy to understand. It is the illustration that was used in the link to Sailing Worlds article. 

The definition of mark room part (b) does not mention proper course. Amy is entitled to room to round or pass the mark as necessary to sail the course without touching the mark. This can include sailing above close-hauled. 
However exoneration does not include RRS 14 if there is damage or injury.

I agree with the definition regarding Mark room, no proper course mentioned.

So Amy can sail sail up top head to wind to come close to the mark and "shut the door" for Ben? That is then the answer I am looking for, is that allowed?

What about 18.2 c 2?

That seems to set a limit the room Amy can argue for when steering above proper course, or why is proper course mentioned there? This is the base of my question. Is the word proper course needed, is it a limitation, or what does it add? To me it adds a restriction to how Amy can steer her boat, or at least outside proper course she is not entitled to room?

Proper Course A course a boat would choose in order to sail the course and finish as soon as possible in the absence of the other boats referred to in the rule using the term.

Maybe my understanding of proper course is wrong. I have always thought of it as the course a boat  would steer without any other boats around. 

Both you and the author of the article refer to that above close haul can be proper course. Can it be proper course to sail above close haul, ie to give the boat Ben more dirty air. Then proper course seems to take into account that there are other boats around to take into consideration. 

I am getting confused on a higher level, but thank you for pointing out all the details. 

 

A boat always has a proper course.  There are only a few occasions when she is obliged to sail her proper course, or not sail above her proper course.
When 18.2c2 applies the inside boat must give the outside, entitled to mark room, boat  not only room to round or pass the mark, but also room to sail her proper course, if this is different to room to round or pass the mark.

Re-reading your description of the incident I have some questions:
- did you luff before reaching the mark? If so did you luff on to a course heading straight at or above the mark?
- did you luff at the mark? Was sailing above close-haued part of the mark rounding?

Yes, I agree. 

Can you than apply this to the Amy/Ben situation? It seems to be an example of the 18.2c2? 

What happens if Amy is not sailing her proper course while overlapped. In this case above proper course  when Amy luffs to the mark above close haul? 

I think the way that John A has reframed the question is the best way to think of this.  The question should be: if a boat sails a particular course does she break any rules and, if she does, is she exonerated for breaking the rule?

I think it is much easier to think about rule 18 as one of obligation (to give another boat mark room per the definition of mark-room or by 18.2(c)) and exoneration (while sailing within the mark room she is entitled to she is exonerated for breaking a specific list of rules).  A boat entitled to mark-room is not obligated to sail in that mark-room at all times.  However, she is still entitled to that room from wherever she is at that moment until rule 18 turns off.  This means that she can sail from wherever she is at that moment to the mark and around it and be in the mark-room she is entitled to.  She is not required to sail in the mark-room the entire time.  The notion of seamanlike rounding or proper-course doesn't come into this beyond rule 18.2(c) expanding the definition of mark-room to sailing her proper course.

Consider Rule 14 separately.  Before you can consider rule 14 you have to know which boat was right-of-way or entitled to mark-room.  That information comes from the other rules analysis.

Looking at the specific case, in position 2, suppose Amy alters course rapidly from where she is to point at the mark, "closing the door".  Amy is a leeward right of way boat (rule 11).  As a right-of-way boat, when she alters course she has an obligation to give a keep clear boat (Ben) room to continue keeping clear (rule 16).  If Ben can't keep clear or hits the mark trying to keep clear, Ben breaks rule 11 but is exonerated for that because, by turning rapidly, Amy has broken rule 16 (rule 43.1(a)).  But Amy, per rule 18.2(b), is entitled to mark-room from Ben, i.e. the room to sail from where she is 'to the mark and around it'.  Since Amy is now pointing at the mark and has not gone around it yet, she is sailing within the mark-room to which she is entitled to and rule 16 is one of the rules she gets exoneration for if she breaks it, rule 43.1(b).  Because Ben has prevented Amy from sailing in the mark-room to which she is entitled, Ben has failed to give Amy mark-room and breaks 18.2(b) and is not exonerated.

So:

Hey - we covered all the exoneration parts! :-D

If there is contact between the boats, you then look at each boat.  Was it reasonable for the boat to have avoided contact?  Certainly, as a keep-clear boat and one obligated to give mark-room, Ben could have avoided contact by not putting himself there.  Amy, as the right-of-way boat and one entitled to mark-room, could have avoided contact by not turning so rapidly.  In my opinion, both boats should be found to have broken rule 14 and Amy would not be exonerated for her breach if there is damage or injury

Brilliant and very elaborate answer John! 

I follow you line of reasoning, step by step. Thank you for the time you put into writing it! 

I very content with your conclusion since I was Amy in the situation ;) 

I am sorry if I get hung up on the wording in 18.2c2. Does it matter if Amy sails her proper course when turning rapidly, or turning quickly close to irons pointing at the mark (not sailing proper course in my mind). 

I am so thankful for all of you contributing with your thoughts!  

Thanks Bjorn.

When you look at 18.2(c), what it is doing is adding an additional obligation to the boat that is already obligated to give mark-room (Ben).  When Ben becomes overlapped inside the boat entitled to mark-room (Amy) not only does Ben have to give Amy room to sail to the mark and around it (mark-room), Ben also has to give Amy room to sail her proper course.  It basically makes the area where Amy gets exoneration bigger (and never smaller).

Unlike the obligation on the inside, overlapped, right-of-way boat to sail no farther from the mark than her proper course that is created by rule 18.4, 18.2(c)(2) does not create an obligation on the boat entitled to mark-room to sail a proper course.  It gets them any extra room they need to sail a proper course if they want to. 

You can also think of this difference as that between a tactical (proper course) rounding and a seamanlike rounding.  Mark-room is typically room to make a seamanlike rounding.  This allows a boat any additional room needed to make a tactical rounding.

In most leeward mark situations it is hard to see how 18.2(c) comes into play as the inside boat is typically also a windward boat and thus a keep-clear boat under rule 11.  It is easier to illustrate the idea at a windward mark.

Yellow enters the zone clear ahead of Blue.  In position 4 Blue has established an inside overlap.  Blue is required to give Yellow mark-room under 18.2(b) based on position 1 and 18.2(a) will not apply because 18.2(b) does.  Because Blue is required to give mark-room under 18.2(b), we have to look at the two parts of 18.2(c) to see if they also apply.  18.2(c)(1) says that even though Blue is now an inside overlapped boat, she is still obligated to give Yellow mark-room.  Blue does not get mark-room just because she is now an inside boat, i.e. 18.2(a) does not apply.  18.2(c)(2) says that in addition to getting mark-room, Yellow gets the additional room to sail her proper course around the mark.

Suppose that Yellow thinks her best course is to turn 180 degrees at the mark and do a gybe set.  If all she was entitled to is mark-room (room to sail to the mark and around it) then Blue can reasonably argue that she gave mark-room because Yellow has been able to sail to and around the mark and that Yellow has broken rule 11 in position 4.  However, because rule 18.2(c)(2) applies, not only is Blue obligated to give Yellow mark-room, but Blue is also obligated to give Yellow the room to sail her proper course around the mark while they are still overlapped.

At Position 2, in the OPs post, two rules apply between Ben and Amy.

(1) Rule 11.  Ben is required to keep clear of Amy as windward boat. Amy DID NOT establish her overlap from astern so Amy can luff above close hauled. Ben is not exonerated under 43.1 because (a) Amy has not broken a rule and (b) Ben is not entitled to mark room.    As long as Ben can escape by luffing the wrong side of the mark such that he is not exonerated by Amy's breach of 16.
(2) Rule 18.2 (b).  Amy can sail directly at the mark because Mark room entitles her to sail "to the mark" even if that is above close hauled.


It gets tricky after position 2.  Once Ben has no options ,he is entitled to room under rule 16.  Amy can luff above close hauled provided she leaves Ben room not to break rule 31. She can luff to proper course (which is almost never above close hauled). She can luff to the the "course as necessary"  (which is also almost never above close hauled) . But if Amy has rounded the mark and the "course as necessary"   is close hauled,  then she takes great risk IMHO, luffing Ben above CHC into the right hand side of the mark.

Wow John, your commitment and explanations are so good! 

I now understand that 182.c2 gives more "rights" than mark room gives. I makes perfect sense the way you describe it. 

Justin, thanks for your thoughts as well. It is the risk Amy takes luffing almost into irons sailing towards the mark (if I exaggerate the situation) that is the core question. 

Thank you all for putting so much time inte answering! 

John C re: "A boat entitled to mark-room is not obligated to sail in that mark-room at all times.  However, she is still entitled to that room from wherever she is at that moment until rule 18 turns off.  This means that she can sail from wherever she is at that moment to the mark and around it and be in the mark-room she is entitled to.  She is not required to sail in the mark-room the entire time."

A while back I had an offline discussion with a rules-expert about this very description above. It is a bit of a catch-22 problem because if a boat's MR follows her around while she sails in the zone, how can a boat ever sail outside of the MR she is entitled to while in the zone?   What does this do to Case 75's description of the "corridor"?  

How do we parse and describe the distinction clearly?

Ang - that's the problem with analogies, they aren't perfect.  The concept of a corridor is useful when talking about where the boat can sail starting at that moment and be entitled to the exoneration that comes from mark room.  But that is predicated that that is where the boat is headed at that moment, i.e. a boat has to be sailing 'to the mark and around it' to be in the corridor.  You could think of it as the corridor not existing until you are in it.  Once you are sailing 'to the mark and around it', the corridor magically appears.

Consider these two scenarios (sailed in boats that can easily sail DDW)

In this case Blue is sailing 'to the mark' and would be considered to be in the mark-room 'corridor'.  She would be exonerated for breaking rule 10.

Now consider this case in the same boats.

While Blue could easily be sailing to the mark, she isn't.  So, at that moment, she is not sailing in the mark-room 'corridor' and does not get exonerated for breaking rule 10 if Yellow has to take avoiding action.

Putting it all together

In position 1, because Blue is not sailing 'to the mark' she is not in the mark-room 'corridor' and would not be exonerated for breaking rule 10 at that moment.  If she continues on this course and interferes with Yellow would break rule 10.

Between positions 1 & 2, Blue bears away and Yellow maintains her course.

In position 2, Blue has borne away to a course that will take her as close as she can go to the mark and because Blue is now sailing a course 'to the mark', the 'corridor' has magically appeared and she is in it and her exoneration 'turns on'.  Yellow has not had to take avoiding action yet so Blue has not broken rule 10 prior to this point in time.

In position 3, Yellow has had to take avoiding action to keep from hitting Blue.  Blue has broken rule 10, but because she has been sailing in the mark-room 'corridor' since position 2, she is exonerated for breaking rule 10.  And Yellow has met her obligation to give Blue mark-room.

I think this is all consistent with Case 75.  The case only talks about the corridor that exists at position S1 and not how that corridor changes as the boats progress to position S2.  Also, this case is as much about sailing outside the corridor.  I.e. a right-of-way boat is not required to stay in the corridor and can sail a proper course provided she complies with the other right-of-way rules.  The case actually gives a false sense that a keep-clear boat is somehow required to stay in the corridor.  This isn't true, it's just that when outside the corridor exoneration is no longer available.

Reference to proper course in Case 63 

Before 2009, the last paragraph of Case 63 consisted of only text similar to the first sentence of the current version of the Case and there was no mention of proper course.

In 2009, RRS 18 was changed to refer to mark-room, and the Definition of mark-room, referring to room for a boat to sail her proper course at the mark, was introduced.

The 2009 version of Case 63 then included an additional sentence at the end of the last paragraph

The risk she takes is that the boat entitled to mark-room may be able to close the gap between her and the mark while sailing her proper course.

The reference to 'sailing her proper course', together with the then current definition of mark-room meant 'sailing within the mark-room to which she was entitled'.

As we know, in the 2013 rewrite of the RRS the Definition of mark-room was promptly amended to remover reliance on proper course.

Case 63 could have been amended in 2013 to remover reference to proper course or substitute it with 'sailing within the mark-room to which she is entitled', but this did not and has not happened.

It is certainly true that if a boat is sailing her proper course around a mark is sailing within the room or mark-room to which she is entitled, but proper course is not a necessary condition for that.