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Tacking on a mark, room to keep clear?

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JimC View Drop Down
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Post Options Post Options   Quote JimC Quote  Post ReplyReply Direct Link To This Post Posted: 21 May 19 at 12:43pm
But what's the alternative?
Seems to me the choices are:
- Rules that can cope with 95% of situations, necessarily fairly complex - what we have now.
- Much simpler rules that rely on keeping boats out of close proximity - Colregs, which means no close quarters mark rounding.
- Simplified rules that don't cover all situations, and an acceptance of "racing incidents" - no fault collisions. Like Motor racing.

I'll stick with what we have as least worst...
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Post Options Post Options   Quote Eisvogel Quote  Post ReplyReply Direct Link To This Post Posted: 21 May 19 at 12:32pm
I don't know, but ongoing discussions like this indicate to me that the rules are rather too complicated. How can you process all this within a few seconds when approaching a mark? Especially if you're not an Olympic (or National) level sailor, but someone who goes round the cans at the weekend...
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Post Options Post Options   Quote Brass Quote  Post ReplyReply Direct Link To This Post Posted: 21 May 19 at 12:09pm
Originally posted by mozzy

Originally posted by Brass

Mark-room never "includes a tack". It may include "room to tack" but this only applies until the boat passes head to wind and mark-room ceases. 
Whats the point in including room to tack mark room definition when it switches of the instant it's applicable? 

That's a question I've been struggling with for quite some time.

Here's my best attempt at a background analysis.

In the pre-1995 RRS room for an inside overlapped boat at a mark was defined, within the room at marks and obstructions rule and included ‘space to tack or gybe when either is an integral part of the rounding or passing manoeuvre’.

Those pre-1995 RRS also provided that:

·         an inside overlapped boat approaching a mark was entitled to room to pass the mark including ‘space to tack or gybe’

·         a boat clear ahead approaching a mark that tacked to round the mark was subject to the While Tacking right of way rule and was NOT entitled to any ‘space to tack or gybe;.

The 1995 rewrite of the RRS provided a general definition of room in Definitions that did NOT include ‘space to tack’, and ‘space to tack’ was not provided in the room at marks and obstructions rule (rule 18), or elsewhere.

The 1995 RRS provided that:

·         a boat that was overlapped inside before or when reaching the two-length zone, was entitled to room to pass the mark, room as defined in Definitions and not mentioning space to tack or gybe;

·         a boat that was clear ahead when she reached the two-length zone remained the right of way boat even if an overlap is established later, but if she tacked she ceased to have right of way and rule 13 applied.

 

Seemingly the intention to privilege an inside overlapped boat, over one clear ahead was preserved and the 1995 drafters thought that room to pass the mark included room to tack without saying so.

Cases 15 and 81, decided in 1966 and 1983, about mark-room switching off in a tack, both concerned a boat clear ahead tacking, so were not inconsistent with this view.  Case 95 was not decided until 2000.

 

The 2005 rewrite of the RRS introduced the defined term mark-room and the three length zone.  All mention of right of way boat with respect to mark-room was deleted, so that rule 18 only dealt with obligations to give mark-room, and no depended on or changed any right of way obligations, reconciling Section A right of way breaches with mark-room breaches by means of the exoneration mechanism.

The definition of mark-room re-introduced the issue of whether mark-room included room to tack by saying ‘mark-room does not include room to tack unless the boat is overlapped to windward and on the inside of the boat required to give mark-room’.

This bespeaks an intention to maintain the privilege accorded to an inside overlapped boat, but note the ‘back-handed’ wording stating what mark-room does not include.

These changes are consistent with the current wording of the rules.

In my opinion, whatever the intention of the drafters of the rules may have been, according any form of mark-room to a boat, once she has passed head to wind is outright contrary to rule 18.1, which disapplies the whole of rule 18 to a boat that passes head to wind, as confirmed by Case 95.  The negative formulation of the reference to room to tack in the Definition of mark-room is completely insufficient to displace the plain words of rule 18.1 and Case 95.


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Post Options Post Options   Quote Fatboi Quote  Post ReplyReply Direct Link To This Post Posted: 21 May 19 at 11:52am
Originally posted by Sam.Spoons

Blue is clear ahead throughout the sequence?
You are 100% correct... Post edited to sort out 
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Post Options Post Options   Quote Sam.Spoons Quote  Post ReplyReply Direct Link To This Post Posted: 21 May 19 at 11:44am
Blue is clear ahead throughout the sequence?
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Post Options Post Options   Quote Fatboi Quote  Post ReplyReply Direct Link To This Post Posted: 21 May 19 at 11:00am
"Mark-Room Room for a boat to leave a mark on the required side. Also, (a) room to sail to the mark when her proper course is to sail close to it, and (b) room to round the mark as necessary to sail the course. However, mark-room for a boat does not include room to tack unless she is overlapped inside and to windward of the boat required to give mark-room and she would be fetching the mark after her tack" 
http://www.sailing.org/tools/documents/WorldSailingRRS20172020new-[24067].pdf

If blue goes into the zone clear ahead and they can get tight to the mark, then realistically they can tack without infringing yellow. They will start the tack as the bow passes the mark and in order for yellow to round they would follow blue line.

If blue cannot get tight to the mark so when they go for a tack, yellow would have to avoid, then blue should wait for yellow to round. 

The other scenario and common at a ww mark is blue can call room for and stbd boats and use them as a way to execute a tack legally. Yellow would then have to peel low to get over the layline and round, or tack to allow blue room for the stbd boat.


Edited by Fatboi - 21 May 19 at 11:52am
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Post Options Post Options   Quote Guests Quote  Post ReplyReply Direct Link To This Post Posted: 21 May 19 at 8:25am
Originally posted by Brass

Mark-room never "includes a tack". It may include "room to tack" but this only applies until the boat passes head to wind and mark-room ceases. 
Just read case 95. Seems to make zero sense. 

A boat only changes tack when they cross head to wind, up to that moment they are just heading up. Whats the point in including room to tack mark room definition when it switches of the instant it's applicable? 

Blue is free to head up to head to wind anyway, because doing so is within her mark room. Heading up to head to wind is not tacking. 

It would makes sense if the definition was giving an inside overlapped boat room to go from head to wind to close hauled without breaking rule 13, but case 95 contradicts that idea.  

I think it would be good if the rules had a definition for tack the verb. The definition of the noun defines two tacks of which you can be on one or the other, but gives no indication of  period when one might be tacking. 

Rule 13 seems to imply that 'while tacking' includes 'After a boat passes head to wind, she shall keep clear of other boats until she is on a close-hauled course.' 
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Post Options Post Options   Quote Brass Quote  Post ReplyReply Direct Link To This Post Posted: 20 May 19 at 11:21pm
Originally posted by ClubRacer


Originally posted by mozzy

  It seems odd that Blues mark room includes a tack when overlapped inside, but not when clear ahead. Why is that?


I Presume it is because if Y was so close to leeward of B that B couldn't tack without the transom stepping out and hitting Y then both boats would be locked until Y bore away to allow B to tack anyway 
Wild guess


Mark-room never "includes a tack". It may include "room to tack" but this only applies until the boat passes head to wind and mark-room ceases.

The arch-typical example of room to tack Elvstrom gives is, for a boat with a large overlapping Genoa, like a FD, getting room to release the genny, and have it flag out to leeward as she comes up into the tack.

I would be inclined to say that a stern-kick was just a boat sailing to, or around the mark.

Edited by Brass - 20 May 19 at 11:22pm
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Post Options Post Options   Quote Brass Quote  Post ReplyReply Direct Link To This Post Posted: 20 May 19 at 10:41pm

Sorry guys, but this discussion is yet again highlighting the problems caused by using language that is not in the rules.

The rules do not use the word "tacking" or the phrase "complete a tack", nor do they say that, in any circumstances mark-room "includes a tack".
Originally posted by mozzy


Blue (B) clear ahead of Yellow (Y) and slightly to leeward at 3 boats, both boat over the port layline on port. Proper course for both boats is to tack on the mark. 
18 applies before B tacks and Y is clear astern so must give B mark room. Rule 21 exonerates B whilst sailing in her mark room for Section A plus rules 15 and 16.  But, at which point is B tacking and therefore not sailing within her mark room?

As diagrammed, B is always sailing within the mark-room to which she is entitled.

@3 + delta she will have passed head to wind and rule 18, in its entirety ceases to apply (Case 95).

@2, B is sailing in to the mark.

@3 B is sailing as necessary to round the mark.

Between @2 and @3 B is sailing within the mark-room to which she is entitled, and she can change course to round the mark as hard and as fast as she likes and will be exonerated by rule 21 if she breaks rule 16.

Between @3-delta and @3, as others have said, B can slow her turn and speed as she chooses and force Y to go around her, as long as she does not pass head to wind.



And at which point are they on port and starboard and so 18 no longer applies?

When B has passed head to wind.

Ignoring the mark the boats are going fast enough that Blue can't complete their tack and give yellow room to keep clear, so would either break 13 or 15.

or B would break rule 16 if she comes up so hard that she doesn't give Y room to keep clear.

But as they are approaching the mark, and B was clear ahead Y should be giving blue mark room right up until position 3

Yes. AND keeping clear (rules 12 then 11)

(or maybe after when the tack is complete?)?

No. Mark-room goes off when B passes head to wind


The situation could be on a tight reach to mark your course requires you to tack around or two boat over-standing a port layline.
 



This example, with B on the layline, and able to come head to wind at the mark, contrasts with Case 15, where the boat clear astern was able to pin out the boat ahead,

Case 15
Definitions, Mark-Room
Rule 12, On the Same Tack, Not Overlapped
Rule 13, While Tacking
Rule 18.1(b), Mark-Room: When Rule 18 Applies
Rule 18.2(b), Mark-Room: Giving Mark-Room
Rule 18.2(c), Mark-Room: Giving Mark-Room
In tacking to round a mark, a boat clear ahead must comply with rule 13; a boat clear astern is entitled to hold her course and thereby prevent the other from tacking


Edited by Brass - 20 May 19 at 11:00pm
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Post Options Post Options   Quote JimC Quote  Post ReplyReply Direct Link To This Post Posted: 20 May 19 at 8:16pm
You can go head to wind before it counts as a tack, so unless its howling, in which case no-one should be playing 6 inch apart games anyway, a nice slow tack at the mark should see blue well clear.
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