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SteveB00
Newbie Joined: 30 Nov 13 Location: Sydney, Oz Online Status: Offline Posts: 24 |
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Topic: Proper Course Posted: 30 Nov 13 at 11:31pm |
Hello.This is my first post here, and I'm looking for some clarification of rule 17. Here's the situation:
2 boats are broad reaching under spinnaker in consistent breeze, the faster boat (L) is clear astern and to leeward of the slower boat (W). L forms an overlap within two hull lengths to leeward of W and continues to sail faster than W until she is ahead, but still overlapped, at which point her wind becomes variable and light and her spinnaker starts to collapse. She responds to this by coming up. Is this a proper course? L would argue that, even in the absence of W, had the wind become variable and light, she would have responded by coming up (to create more apparent wind). W would argue that L's wind only became variable and light because of the affect of W's sails on L, so that, in coming up, L is sailing above a course she would have sailed in W's absence. Who's right? Thanks in advance, Steve = : ^ ) P.S. This isn't academic; it happened to me yesterday. |
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Brass
Really should get out more Joined: 24 Mar 08 Location: Australia Online Status: Offline Posts: 1146 |
Post Options Quote Reply Posted: 01 Dec 13 at 3:19am |
Welcome.
You have obviously grasped the relevant concepts and issues in rule 17. The solution to your problem depends on a matter of fact: Was the change in apparent wind affecting L caused by W or not? You described W and L broad reaching, presumably with AWA between 90 and 135 degrees aft. You then say L sailed through W's lee 'faster than W until she is ahead, but still overlapped', so, presumably L gets about half a boat length advanced on W. If boats were sailing hot, up towards 90 degrees AWA, I would be fairly confident that, at that time, if L was half a boat advanced on W, L was sailing in breeze that was not (or no longer) substantially interfered with by W, any change in wind strength or direction was not a result of W and luffing to maintain pressure by L was sailing her proper course. OTOH, if boats were sailing deep, at 135 or more degrees AWA, W's wind shadow will be projecting off her leeward bow and will probably still be having some effect on L, although, at half a boat length advanced, L's headsail should be in clear air. If W brought evidence to a protest hearing that she observed the breeze was consistent in strength and direction throughout, then the protest committee might infer that any change in wind experienced by L was as a result of W, and that here change in course would not have been made in the absence of W. OTOH, if W could not bring strong affirmative evidence that the wind remained steady, and L gave evidence that it changed and weakened, then there would be a good chance that the protest committee would accept L's version and conclude that her luffing was what she would have done in response to a wind change in the absence of W.
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SteveB00
Newbie Joined: 30 Nov 13 Location: Sydney, Oz Online Status: Offline Posts: 24 |
Post Options Quote Reply Posted: 01 Dec 13 at 3:46am |
Thanks for the thorough reply. I think we can be confident that, at least in some measure, the weakening of L's wind was due to the presence of W, and that I owe someone an apology. :-[
Thanks again, Steve = : ^ )
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sargesail
Really should get out more Joined: 14 Jan 06 Location: United Kingdom Online Status: Offline Posts: 1459 |
Post Options Quote Reply Posted: 01 Dec 13 at 9:20pm |
Brass. Interesting. I have previously heard the definition: A course a boat would sail to finish as soon as possible in the absence of the other boats referred to in the rule using the term. As applying to the boat itself, but not to its effect on the wind. The way you express this does create seem to create some oddities: 1. Clear astern approaching from position behind and to L with Assym, sails gradually converging course and becomes becomes L, and is not permitted to respond to the change in wind direction.... 2. Yet Clear astern approaching from dead astern can bear away below proper course to avoid the obstruction and then return to her PC with a luff.... But I'll give you the fact that your last para is the relevant it - it would be for W to prove the wind was steady...
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Brass
Really should get out more Joined: 24 Mar 08 Location: Australia Online Status: Offline Posts: 1146 |
Post Options Quote Reply Posted: 01 Dec 13 at 9:32pm |
The question is, what was the course the boat would have sailed to finish as soon as possible if the other boat had not been there?
1. There is nothing to stop L responding to any change in the prevailing wind. What she cannot do is hot up in response to the decrease in pressure in W's wind shadow. I'd normally expect W to let it slide if L got her nose in front and hotted up across W's bow, as long as L didn't interfere with W, (but not in match racing, particularly now the Elliotts have got Asys). 2. No problem with L sailing below her proper course then coming back up to it.
Edited by Brass - 01 Dec 13 at 9:47pm |
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sargesail
Really should get out more Joined: 14 Jan 06 Location: United Kingdom Online Status: Offline Posts: 1459 |
Post Options Quote Reply Posted: 01 Dec 13 at 10:54pm |
Sorry I still don't follow how the interpretation in point one follows from the defintion....she is not hotting up because the other boat is there - she is hotting up because the wind has decreased. Off to the Call Book now!
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Brass
Really should get out more Joined: 24 Mar 08 Location: Australia Online Status: Offline Posts: 1146 |
Post Options Quote Reply Posted: 01 Dec 13 at 11:00pm |
If the prevailing wind decreases fine.
But if the wind L experiences is lessened because it is in the wind shadow of W, then the there would have been no decrease in wind 'in the absence of the other boat'.
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sargesail
Really should get out more Joined: 14 Jan 06 Location: United Kingdom Online Status: Offline Posts: 1459 |
Post Options Quote Reply Posted: 01 Dec 13 at 11:18pm |
Brass,
I understand what you're saying, but had previously understood another interpretation to be the case.....that it applied only to the boat and not to its effects. I don't see how L - who may not be able to see wind and water to windward of W is expected to be able to say it is not a lull in the wind. How would you make a call as an umpire? The Call Book is no help. Might need to be given Assyms on Elliots! Bed time so not going to look at Cases just yet.
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Brass
Really should get out more Joined: 24 Mar 08 Location: Australia Online Status: Offline Posts: 1146 |
Post Options Quote Reply Posted: 01 Dec 13 at 11:51pm |
Umpires are supposed to have decided what the proper course for both boats is at the beginning of the leg. Umpires Manual
You would tend to assume that W was sailing the proper course, and if W (and L) were sailing deep of what the umpires thought their proper course was, the umpires should have noticed it. Dialogue might go like this: Give Astern. Agree, if you hook me 17 will be on. Agree. Right Leeward, 17 on. Agree, keeping clear, You sailing your proper course? Negative. I'm deep of my proper course, I can come up Agree Luffing, giving room Luffing, keeping clear, I'm above my proper course, 17 on you Negative, Wind has lifted Agree, I'm Give Windward, on proper course, 17 on you Agree Luffing, giving room Luffing, keeping clear, above my proper course 17? Agree, I'm above proper course Y Flag on W 17 Penalise L |
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JimC
Really should get out more Joined: 17 May 04 Location: United Kingdom Online Status: Offline Posts: 6648 |
Post Options Quote Reply Posted: 02 Dec 13 at 8:17am |
Never ever heard that one, and to me it seems a very very strange idea. My answer, I guess, put brutally, is that if you don't know where the wind shadow's going to be you should not be pushing the rule so hard. I'd say that if W hasn't slowed the wind hasn't dropped ought to be a reasonable guide. I wonder who spread such a bizarre corruption of the meaning of the rule? Edited by JimC - 02 Dec 13 at 8:21am |
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