Hi all,

I've mostly been crew on monoslugs for my racing career. Since purchasing my Hobie 18 a few years ago I've been trying to better understand the rules. Last night I was reading the US Sailing Casebook 2006 and came across Case 11 on page 63 and it's been bothering me. Since I haven't been a skipper for very long I could be mistaken, but I totally disagree with the decision of this case. Based on my knowledge I believe PW has no rights in the situation and should have tacked. To do anything else was a violation of the rules by PW. I've never heard of another boat being called an obstruction. I'd like to hear your thoughts?

Brian

I am definitely not a rules expert, so it bothers me, too, because I have been in a very similar situation where I was PL. PW was yelling at me for room to pass behind the starboard boat. I'm thinking, "What the heck is that about?", because PW had plenty of room to tack to avoid the starboard boat.

In my case, PW also had plenty of room to pass behind the starboard boat anyway, so did not need to yell at me for room. However, it has been bothering me ever since, because I just didn't understand the hail by PW. <img src="http://www.catsailor.com/forums/images/graemlins/crazy.gif" alt="" />

It might make some sense if there were another boat close above PW making it impossible for PW to tack (in which case I would think that "other boat" to windward would actually be the "obstruction), but that was not the case in either situation.

Maybe somebody can explain this to us. <img src="http://www.catsailor.com/forums/images/graemlins/tongue.gif" alt="" />

A boat that you are required to keep clear of is by definition an obstruction.

From definitions section of RRS:

"Obstruction An object that a boat could not pass without changing course substantially, if she were sailing directly towards it and one of her hull lengths from it. An object that can be safely passed on only one side and an area so
designated by the sailing instructions are also obstructions. However, a boat racing is not an obstruction to other boats unless they are required to keep clear
of her, give her room or, if rule 21 applies, avoid her."

As the inside boat PW is entitled to room to pass the obstruction in terms of rule 18.2.

When beating to weather, a starboard boat is an obstruction to a port tack boat. PL has rights over PW (windward boat shall keep clear), and can hail for
pw to tack so PL can clear the obstruction (PL must then tack immediately). IF PL elects to go behind the obstruction, he must give PW room to also pass behind the obstruction. He cannot "peel off" PW on the starboard boat.
Make sense?
I do not have the rulebook in front of me, but assume this is the situation you are referring to. If not, please excuse the intrusion.
Ken

No, it doesn't make sense to me -- at least not common sense. <img src="http://www.catsailor.com/forums/images/graemlins/frown.gif" alt="" />

Ken,

In this particular example PL can pass clear astern of the starboard boat without changing course. Take a look at the link for picture and more information. I think PW is in a pickle and has to tack. I'd like to hear others thoughts so I can better prepare for when I run into this in the future.

Brian

Brian,

PW DOESN'T have to tack. Why? Because S is an obstruction (see the definition I quoted earlier)and as inside boat PW is entitled to water to pass an obstruction because Rule 18 says he is.

Brian,
PL is in control. If he wants to tack, PW must allow him. IF he elects to pass behind, he must give PW room to also pass behind.
Ken

But that is if PL needs to alter course to pass behind; right?

There are two different situations here. The one in the ISAF precedent which Brian raised originally where PL doesn't need to tack or alter course to avoid S but PW does - and where PW can demand water from PL to allow him to cross behind S. The other situation is where PL does have to do something to avoid S and can either bear away behind S (and must still give PW room to do the same) or can choose to hail PW for room to tack - in which case PW must give PL room to tack. PL does not have to bear away behind S even if PW wants to go that way.

The second scenario makes sense. The first one sounds like unwarranted charity. BW got hmself into that situation, and he should get himself out by tacking. It's not like he doesn't have any option.

What is scary about this whole thing is that the obstruction definition seems to be saying that all this is happening within one boat length of the "obstruction." I don't think that is even realistic for Optis, much less for catamarans. (Or maybe I am not understanding that part of the definition, since apparently I don't understand much about anything.) <img src="http://www.catsailor.com/forums/images/graemlins/tongue.gif" alt="" />

What it's telling you is that you cannot use other boats as a "pick" (common, but not always legal, basketball / football maneuver). It makes sense to me. It would be a dangerous to boat S if you were allowed to do so.

Why is it dangerous to boat S if WP is capable of tacking? I just don't get it.

LP doesn't have a problem. So why should WP's problem suddenly become LP's problem, when WP has a perfectly viable option? <img src="http://www.catsailor.com/forums/images/graemlins/confused.gif" alt="" />

But WP may not always have a way out - there could be other boats above him who are going to pass behind S who WP will have to hail for room to tack before he could bail out that way. I don't think it's fair to say that it's always WP's fault - remember that the obstruction doesn't have to be another competitor. It could be a boat racing in a different class or (and this comes from the heart!) a commercial ship.

That's why there is Rule 19.1. No?

I think that Jake is right on about why the rule is such. Image if you are the starboard boat and know you are about to be used as a pick? You have to be more than a little bit nervous. The upwind starboard boat is Queen Bee to all but a leeward boat on the same tack. Downwind they are almost Queen Bee, Princess maybe. They should not have to worry about the real possibility that there will be a boat coming over their stern because the rights are fuzzy.

There are three things that can happen at this intersection.

First is that the leeward boat can decide to tack to starboard. In this case the windward boat is obligated to tack due to obstruction.

Second is that if the leeward boat decides to go behind the starboard boat they are required to give room for the obstruction (starboard) to an overlapping windward boat.

Third is that the leeward boat goes behind and the windward boat tacks under starboard. Too many things can happen in this scenario if there are other boats in proximity. One respondent mentioned, there may be other port boats to weather that do not have time to get out of the way if this boat has to do a slam tack.

You have to consider the safest scenario of all. That is the way the rules are made.

Later,
Dan

I'm glad that I now understand that rule, because if I am PL I will know why PW is yelling at me.
And if I am ever PW, it is nice to know that I have the option of asking for room to go behind S.

But in the illustrated case, I think that for PW to try to, at that point, bear off on a reach and go behind S would be the most dangerous scenario, especially for catamarans. If you are talking safety, the safest thing for PW to do at that point is to tack -- especially, of course, in heavy air.

I know, I'm a wimp. <img src="http://www.catsailor.com/forums/images/graemlins/tongue.gif" alt="" />

P.S. I still don't understand the part about being one boat length away from the obstruction. Maybe somebody can explain that.

P.S. I still don't understand the part about being one boat length away from the obstruction. Maybe somebody can explain that. [/quote]

I think it is a matter of relative size. For instance, if you are 10 mi away from a small island, a small change in course will allow you to miss it, but because when you are one boat length away, you can't miss it without substantially altering your course, the island is an obstruction. By the same logic, a lobster buoy will not be an obstruction, because when you are one boat length away, it will only take a small alteration in course to miss it. That is how I would read it.


From definitions section of RRS:

"Obstruction An object that a boat could not pass without changing course substantially, if she were sailing directly towards it and one of her hull lengths from it. An object that can be safely passed on only one side and an area so
designated by the sailing instructions are also obstructions. However, a boat racing is not an obstruction to other boats unless they are required to keep clear
of her, give her room or, if rule 21 applies, avoid her."

As the inside boat PW is entitled to room to pass the obstruction in terms of rule 18.2. [/quote]

If an obstruction does not become an "Obstruction" under the rules until you are one boat length away from it and realize you cannot avoid it, that is a little late to take evasive action; isn't it? I'm just wondering how that definition works in conjunction with the rule being discussed.

The one boat length bit is purely for deciding whether or not the thing in question is an obstruction or not. If you're sailing a 16 foot boat and the S boat is a 60 footer, the test is "If I'm 16ft from S will I have to alter course substantially to miss it?". You don't have to be one boat length away from the obstruction to answer that question!