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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: 04 Aug 15 at 10:06am
Originally posted by laser193713


...if someone gains an overlap from behind (overtaking), in most normal sailing situations, then you are highly likely to be the right of way boat.


Just not true though.

Three possibilities.
You overtake from behind and to windward. You are keep clear boat.
You overtake from directly behind and to leeward. You have right of way but may not sail above *your* proper course, and must initially give the other boat room to keep clear.
You overtake from behind and well to leeward. You have right of way and no restrictions on your course.

In paper/electronic rules discussions there is a lot of virtue in quoting rule numbers because it defines which rules you believe apply, and saves quoting the entire text of every rule all the time. In an on line discussion the rule book is always available to all the participants.

By contrast on the water quoting numbers is not usually very useful.



Edited by JimC - 04 Aug 15 at 12:24pm
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Post Options Post Options   Quote Presuming Ed Quote  Post ReplyReply Direct Link To This Post Posted: 04 Aug 15 at 11:08am
Originally posted by JimC

The trouble with that ultra literal interpretation is that it suggests that if boat A is 1 mm astern of boat B then A is keeping clear of B since B can change course in either direction without making contact.

However, if we go to case 30 and Case 88 it seems that a bit more than that is required. In particular Case 88 says:
‘Keep clear’ means something more than ‘avoid contact’; otherwise the rule would contain those or similar words.


The implications of that seem to me to be are that if the keep clear boat is so close to the other boat that ordinary relative variations in speed through natural changes in wind and water are liable to to bring them in contact without action by the crews then it is not keeping clear. So it seems to me that on small boats on flat water with a steady wind that distance might be a moderate number of inches, on big boats in a rough sea it might be several feet, but either way if astern establishes an overlap on aheads rudder while she is within that sort of range then she was failing to keep clear immediately before establishing the overlap, and the subsequent collision would not have occurred without that rule breach. But I am probably wrong!


In my umpire seminar, John Doerr asked us a question: "do you need contact to prove that you're not keeping clear?" and, of course, we all immediately said "no, of course not". At which point he asked "what about 12? Wouldn't you feel a bit aggrieved if you were binned for not keeping clear if there wasn't contact?" 

At which point, we all agreed with him again. 

Getting that close is very high risk for the trailing boat. & it's also (arguably) less useful if you're trying to control the boat ahead than being a bit further back so that you can always get on the inside of any turn. 


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Post Options Post Options   Quote JimC Quote  Post ReplyReply Direct Link To This Post Posted: 04 Aug 15 at 12:03pm
Take my IC, which has an underslung rudder and a pointed stern. If we get too literal about this if a boat coming from behind makes contact 5mm to leeward of the point then I failed to keep clear of her under RRS11*. If she makes contact 5mm to windward of the point then she failed to keep clear of me under RRS11. Only if she makes contact *exactly* on the very tip of the stern would it be a breach of RRS12. Obviously that's a nonsense.

So there must be a zone around a boat that constitutes not keeping clear, and it must be variable depending on boat and conditions. If you want another situation where being excessively literal starts becoming a nonsense, consider if my canoe makes contact with the leeward side of the windward hull of a catamaran.



Taking that example: people might be aggrieved if DSQd with no contact under RRS 12, but they shouldn't be. However sometimes you know that a rule has been broken, even if you can't define exactly when. Take my example above of the boat that contacts the stern of my IC 5mm to leeward of the point. Do you penalise me under RRS 11, or do you penalise the other boat under RRS12 on the grounds that although you can't be precise about exactly when he failed to keep clear under RRS12, he can't have got in that position without breaking it?


*yeah, OK room to keep clear comes into it, but not the point at issue




Edited by JimC - 04 Aug 15 at 1:01pm
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Post Options Post Options   Quote Presuming Ed Quote  Post ReplyReply Direct Link To This Post Posted: 04 Aug 15 at 2:29pm
LTaking your catamaran example, there is a degree of ambiguity there, which is why in the AC rules they clarified it - as between the hulls is clear astern. And with you IC, what about 30 cm either side? Or 60?

The "wiggle room" requirement only applies to boats on the same tack and overlapped.

 For ISAF case 50 to apply to port/starboard crossings, starboard has to alter course. If s holds her course, and p crosses, then you can't apply 50. No matter how close. 

If, however, in a CA/CAstern situation, Ahead said that they had to alter course to avoid contact, and the boats were gnats wing close, then under 50, astern isn't looking rosy. But if ahead holds her course, then astern is keeping clear. 

In the RYA appeals committee, there are 2 factions (AIUI. I'm not a member). One of "sailors", and one of "lawyers ". The sailors just go " you can't ram people up the chuff" and just leave it at that. 


Edited by Presuming Ed - 04 Aug 15 at 2:32pm
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Post Options Post Options   Quote Rupert Quote  Post ReplyReply Direct Link To This Post Posted: 04 Aug 15 at 8:00pm
"You can't ram people up the chuff" sums things up nicely, thank you!
Firefly 2324, Lightning 130, Puffin 229, Leader, Topper 44496, yellow Minisail
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Post Options Post Options   Quote SoggyBadger Quote  Post ReplyReply Direct Link To This Post Posted: 04 Aug 15 at 8:04pm
Originally posted by Rupert

"You can't ram people up the chuff" sums things up nicely, thank you!


Apparently they don't like it up em LOL
Best wishes from deep in the woods

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Post Options Post Options   Quote Brass Quote  Post ReplyReply Direct Link To This Post Posted: 05 Aug 15 at 12:50am
Originally posted by Presuming Ed

 
...
The definition of Clear Astern and Clear Ahead; Overlap means that, with these boats having transom hung rudders, there is a very brief overlap  - the boats are "rudder overlapped" before contact. 

So 12 doesn't apply.

15 means that Astern has to give ahead room to keep clear, which she didn't. 

If astern hits the windward side of the transom, then she's broken 11. 
Originally posted by Rupert

Wouldn't rule 15 suggest that if you hit a boat on the leeward side of the transom you are breaking a different rule to the one you would be if you hit them on the windward side?

Yes, if the boat has an overhanging rudder (or boom, or bumpkin) as PEd explained in detail.

I can see loads of protest room confusion in that, especially as it is quite possible that the boat being hit will have felt the bump but not seen it, and so not know which side.

Usually a protest committee, having heard evidence that there was contact will seek details, where, damage and so on, which will probably bring out whether the contact was to windward or leeward of the rudder, and then lead straight into the rule 15/rule 11 decision.

If the protest committee does not find fact about which side, or possibly even whether there was a trailing rudder at all, then they're still going to penalise under 11, 12, or 15.

Point is, if the protest committee doesn't realise there's an issue, they're not going to get confused, and if the parties want to raise the issue it's up to them.

In Australia, getting the rule number wrong is not enough to get an appeal sustained (because of a MNA prescription).

Originally posted by JimC

It would seem to, but I was influenced in my thinking by Case 30, which to me seems to be to be saying that the clear behind boat was already failing to keep clear just before she overlapped the rudder of the other boat,

That's how I see it.

There's no reason why B cannot first break rule 12 then become overlapped and break rule 15.

so was the first to break a rule.

I don't think that's relevant.

A protest committee should identify all the rules that are broken in an incident.

My understanding was that subsequent events were a consequence of astern breaking that rule, so ahead gets exonerated. 

A is exonerated for failing to keep clear of the leeward boat in accordance with Case 30.

B's breach of rule 15 was not caused by any breach by A, so no exoneration for B can be contemplated.

So in Brass's point, I guess I hitch my cart to 12, since the subsequent RRS15 breach would not have occurred if astern had kept clear. 

Maybe.

I think Ed's preference for rule 15 is because B certainly broke rule 15 on the face of the rule, but to get to a breach of rule 12, you have to go to Case 30, and argue a matter of degree.

Is that a reasonable guideline for amateur PCs Brass? Look for the first rule breach and penalise for that,

No, I don't think so.  Even an 'amateur' protest committee (you mean you have protest committees that get paid for doing this stuff?) should state conclusions about all the rules that were broken.  There is no precedence in time or importance.

There would be nothing wrong (and a good deal right) with conclusions that B broke rule 12, B broke rule 15, B broke rule 14, A broke rule 11.

Having said that, as I indicated in the responses to Rupert above, if you miss out on a rule breach, as long as you get the right decision, there's little to grumble about.

 and then decide whether subsequent rule breaches by the other boat were inevitable after the first one (in which case exoneration comes in) or alternatively could readily have been avoided (in which case penalise both)?

Rather I think you have to consider exoneration for each rule breach.

I don't think the sequential approach is useful.

Originally posted by JimC

The trouble with that ultra literal interpretation is that it suggests that if boat A is 1 mm astern of boat B then A is keeping clear of B since B can change course in either direction without making contact. 

I don't think Ed was really trying to buck Case 30.

However, if we go to case 30 and Case 88 it seems that a bit more than that is required. In particular Case 88 says: 
‘Keep clear’ means something more than ‘avoid contact’; otherwise the rule would contain those or similar words.
 


The implications of that seem to me to be are that if the keep clear boat is so close to the other boat that ordinary relative variations in speed through natural changes in wind and water are liable to to bring them in contact without action by the crews then it is not keeping clear.

Well the Case 50 guidance is about reasonable apprehension of collision, rather than probability.

So it seems to me that on small boats on flat water with a steady wind that distance might be a moderate number of inches, on big boats in a rough sea it might be several feet,

Yeah  Case 21.

but either way if astern establishes an overlap on ahead's rudder while she is within that sort of range then she was failing to keep clear immediately before establishing the overlap,

Not happy with this:  it sounds a bit doctrinaire.  I think you need to go through the Case 30 reasoning.

Maybe if you added 'and there is contact' it would work better.

and the subsequent collision would not have occurred without that rule breach.

Rule breach is relevant to exoneration for the ahead boat not keeping clear.  May be relevant to a rule 14 breach, but perhaps not so much.

But I am probably wrong! 

Why?  Your batting average here and in SA is looking pretty good at the moment.

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Post Options Post Options   Quote Brass Quote  Post ReplyReply Direct Link To This Post Posted: 05 Aug 15 at 1:07am
Originally posted by JimC

Take my IC, which has an underslung rudder and a pointed stern. If we get too literal about this if a boat coming from behind makes contact 5mm to leeward of the point then I failed to keep clear of her under RRS11*. If she makes contact 5mm to windward of the point then she failed to keep clear of me under RRS11. Only if she makes contact *exactly* on the very tip of the stern would it be a breach of RRS12. Obviously that's a nonsense.

I don't agree it's a nonsense.  It's just the working out of some fairly carefully crafted rules.

Same decision, different rule-path to get there.

So there must be a zone around a boat that constitutes not keeping clear, and it must be variable depending on boat and conditions.

I agree with that,

A distance around an object that it is not seamanlike to sail closer than ...

It's a very handy concept for understanding the rules, particularly room.
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