Chichester Marina hazard to navigation warning

Who was at fault

  • Raggie 1

    Votes: 14 9.8%
  • Raggie 2

    Votes: 1 0.7%
  • Stinker

    Votes: 115 80.4%
  • Other, please specify

    Votes: 13 9.1%

  • Total voters
    143
The deviations from the actual text totally distort the meaning.

The actual text is:

"A vessel of less than 20 metres in length or a sailing vessel shall not impede the passage of a vessel which can
safely navigate only within a narrow channel or fairway. "


The mobo in the video was a vessel of less than 20 metres in length.

And there is no word "motor" in the phrase, "a vessel which can safely navigate only within the channel."

I bet you also are not aware of the fact that even a vessel OVER 20 metres, even a ship, would be obligated to give way to sail, once a risk of collision arises. Rule 9 does not nullify Rule 18 -- it starts applying earlier.

Well you are wrong because my text is from the chichester harbour bye-laws, not the colregs
 
Years ago I was teaching DS skipper theory in evening classes and someone asked "Are you allowed to tack into someone's path, creating a risk of collision, or are you obliged to prevent a risk of collision ever arising?" We consulted RYA HQ who, after taking some time to consult, said "There is no obligation to prevent a risk of collision arising, but after it has arisen you have to follow the rules".
Intriguing example.
Just for the sake of checking if my understanding of what was discussed so far is correct, isn't that complete bollocks?
I mean, your student asked if you are allowed to tack into someone path IN GENERAL, without specifying a context where tacking was predictable - hence equivalent to holding course and speed.
If Mr.Dashcam would have overtaken the sailboat in open water, while she was following a straight course on her port tack, and right while the mobo was overtaking on her stern would have tacked out of the blue, ramming into the stbd side of the mobo, wtf would the moboer have been supposed to do to avoid that?!?
 
One of the many terrible things about IRPCS is that they presume that only two vessels are involved. In practice it is common for boats to be simultaneously stand-on and give way. Dammit, they don't even define what a "risk of collision" is.

Years ago I was teaching DS skipper theory in evening classes and someone asked "Are you allowed to tack into someone's path, creating a risk of collision, or are you obliged to prevent a risk of collision ever arising?" We consulted RYA HQ who, after taking some time to consult, said "There is no obligation to prevent a risk of collision arising, but after it has arisen you have to follow the rules".

Yup, though actually that is in my book one of the smaller terrible things. I'm typing quickly and wont recall the full list of questionable things, but it contains at least:

1. assumption of two boats, as you say
2. Truly terrible drafting. What is the difference between keep out of way of and not impede? What is difference between not impede passage and not impede safe passage? The draftsman has gone to the trouble of creating the distinction (see 8f(i)) yet not told us what it is - thanks a bunch. What's a safe distance? It's not the same as one in relation to which you don't say "Sheesh, that was close!" And so on.
3. Some apparent conflicts that are at best hard to figure out for Joe Public - if >20 metre motor boat is in narrow channel with a sailing boat who has "right of way"? (I use that term only colloquially of course)
4. Plenty of points that almost no-one can figure out - Dockhead is highly qualified legally but even he wasn't aware of the true legal obligations of the stand on vessel under 17(a)(i) as this thread shows. It should just not be that hard. Colregs should define exactly what stand-on means and basically incorporate the principles of 100 years of case law into the actual words of Colregs, so everyone can just read it and see it.

Then you have the philosophical question about the stand-on rule - this requires one party broadly to do nothing and trust the other to fix things. As stand on, you are trusting someone you don't know. Humans prefer to take action themselves and you can argue it would be better to permit the stand on guy himself to do something more than 17(a)(ii) currently permits - this is a very complex argument and I'm merely highlighting the issue not taking any side, though it has been perfectly well fixed for road traffic. There is research showing that lots of skippers ignore stand on and take action themselves - human nature.

I've said on here for a decade+ that Colregs is a terrible document, but others say passionately that it is ok and has stood test of time (parts of it date back to about 1860). So there isn't agreement on that fundamental issue!

Anyway, back to your "two vessels" point: there is plenty of court precedent dealing with it and saying that if A is stand on to B, but A itself has to give way to C, then B must anticipate the move that A will make to give way to C; A is not required literally to stand on. That principle doesn't fix every problem that arises from the "2 boats assumption" , but it is a start.

And finally, yes, risk of collision. In my head, the word "risk" means the possibility of different outcomes. I think that in other people's heads risk means just that something bad is going to or might happen. As a matter of physics, 2 boats that hold their speed and course will either collide or not; there is certainty, not risk, at least in my book. The uncertainty of course comes from lack of physics data available to the skippers, and therefore the risk is only in the minds/guesswork of the two skippers. That's how it has to be of course, but if we are crossing and you're stand on I might judge that I'll cross astern of you and you might estimate that we'll collide, so now we are working from different assumptions, and you're being unnecessarily stressed out. This could all be fixed by rewriting colregs
 
Intriguing example.
Just for the sake of checking if my understanding of what was discussed so far is correct, isn't that complete bollocks?
I mean, your student asked if you are allowed to tack into someone path IN GENERAL, without specifying a context where tacking was predictable - hence equivalent to holding course and speed.
If Mr.Dashcam would have overtaken the sailboat in open water, while she was following a straight course on her port tack, and right while the mobo was overtaking on her stern would have tacked out of the blue, ramming into the stbd side of the mobo, wtf would the moboer have been supposed to do to avoid that?!?

Sorry, I should have given more context. It wasn't a case of tacking into someone's path without giving them time to react. I think the situation from which the discussion arose (it's a long time ago, so forgive hazy memory) was two motor boats proceeding on parallel paths, some distance apart. Nobody overtaking, so no stand on boat. The boat on the left is free to change course to converge with the boat on the right, even though the boat on the right becomes give-way as a result.

Basically, you are allowed to create a risk of collision.
 
Here you are
A beautiful landscape indeed, thanks for sharing it with us.

Brings back memories of the beautiful cruise scubaman gave me the opportunity to experience, along the countless islands from Helsinki to the Russian border, and then further East in Russian waters up to Vyborg, eventually returning to Finland through the Saimaa canal.
We weren't as lucky as yourself with the weather, but not too bad either, considering that we made the trip in September.
A fantastic boating area indeed, even if a tad colder than the Med... :)
...I can definitely see why you enjoyed the cruise! :encouragement:

PS: many thanks again scubaman!
 
Sorry, I should have given more context. It wasn't a case of tacking into someone's path without giving them time to react.
.....
Phew! That sounds much better.
If sailboats were always allowed to tack into my path as they please, I might consider upgrading my onboard safety equipment, keeping always an RPG handy.
After all, if the worse comes to worst, one sank boat is still better than two, I reckon... :rolleyes: :p
 
. . . . What is the difference between keep out of way of and not impede? What is difference between not impede passage and not impede safe passage? The draftsman has gone to the trouble of creating the distinction (see 8f(i)) yet not told us what it is - thanks a bunch. . . .

There is actually an answer to that question :) And I certainly agree that it's not easy to figure out just from the text of the Rules. It's been partially fixed by interpretation, and was clarified slightly with amendments to Rule 8. This particular question really puzzled me and I spent a lot of time on it a few years ago.

If you are required to "not impede" another vessel, it means you are supposed to maneuver in such a way that you don't interfere with the other vessels passage -- you do not create a situation which requires him to maneuver. For example, if you are crossing a TSS, you are supposed to plan your crossing so that you pass behind other traffic, or far enough ahead that it doesn't have to maneuver in case you're the stand-on vessel.

However, your obligation to "not impede" does not change the status of stand-on or give-way, and doesn't modify the obligations of the stand-on vessel and give-way vessel, once a risk of collision has arisen (and vessels are in sight of one another, of course).

So it means if you screw up and end up crossing ahead too close for a safe pass, then once the risk of collision has arisen, and you are the stand-on vessel under the steering and sailing rules, you are obligated to stand-on while the give-way vessel maneuvers.

Bizarre, but that's how it's intended to work.


I agree that the COLREGS are obscure, and in some places exceptionally hard to understand.
 
If Mr.Dashcam would have overtaken the sailboat in open water, while she was following a straight course on her port tack, and right while the mobo was overtaking on her stern would have tacked out of the blue, ramming into the stbd side of the mobo, wtf would the moboer have been supposed to do to avoid that?!?
Yup!
To be legally clear, the rules do not impose an obligation not to create risk of collision, nor do they impose obligation not to collide per se
Mobo in your precise example MapisM is not in breach of any rule, subject to the big exception in next para. Once the sailboat has tacked, and during the say 2 seconds after that and before the collision, mobo's obligation is contained in rule 16 which says "Every vessel which is directed to keep out of the way of another vessel shall, so far as possible, take early and substantial action to keep well clear." - my emphasis. The sailboat's obligation, if it was so close that the mobo couldn't avoid the collision if the sailboat tacked, was to hold course and speed, and it was in breach of that by tacking. So the sailboat seems in the wrong and the mobo seems right (subject to next para). If you overlay the general seamanship rules in 2b you can say the mobo shouldn't be so close but also that the sailboat shouldn't have tacked
The big exception is that mobo started off needing to keep clear of sailboat (either as overtaker, or as mobo v sail) and that obligation contains in rule 16 "substantial action ... well clear". Also 8(d) obliges mobo to position himself at "safe distance". In your scenario mobo will therefore surely get significant % blame for being so close
 
There is actually an answer to that question :) And I certainly agree that it's not easy to figure out just from the text of the Rules. It's been partially fixed by interpretation, and was clarified slightly with amendments to Rule 8. This particular question really puzzled me and I spent a lot of time on it a few years ago.

If you are required to "not impede" another vessel, it means you are supposed to maneuver in such a way that you don't interfere with the other vessels passage -- you do not create a situation which requires him to maneuver. For example, if you are crossing a TSS, you are supposed to plan your crossing so that you pass behind other traffic, or far enough ahead that it doesn't have to maneuver in case you're the stand-on vessel.

However, your obligation to "not impede" does not change the status of stand-on or give-way, and doesn't modify the obligations of the stand-on vessel and give-way vessel, once a risk of collision has arisen (and vessels are in sight of one another, of course).

So it means if you screw up and end up crossing ahead too close for a safe pass, then once the risk of collision has arisen, and you are the stand-on vessel under the steering and sailing rules, you are obligated to stand-on while the give-way vessel maneuvers.

Bizarre, but that's how it's intended to work.


I agree that the COLREGS are obscure, and in some places exceptionally hard to understand.
Many thanks DH. That's a really helpful description, and I have struggled with this one a lot (I got interested in it when I was driving my 24m mobo up and down the Hamble:D:D). I agree your analysis, except that I am not sure you have dealt with the opening line of rule 18 "Except where Rules 9,10 and 13 otherwise require...". Are you saying that you think your description above is correct, even taking those opening words into account? How come? Why is 18(a)(iv) not subservient to 9b? I don't get that. I haven't got to bottom of this one nor studied case law so I'm definitely asking a question here rather than arguing against you

The problem is relevant because the "sailboat doesn't impede motorboat >20m" scenario is, in our daily lives, much more likely in a narrow channel (like Chichester in that video) than TSS. In a channel, anything more than 150m away is almost irrelevant and only very close boats are of interest, unlike the open sea. So risk of collision, the mobo's 18(a)(iv)obligation to keep clear of sail, and the sailboat's 9b obligation not to impede, all suddenly occur at the moment. And you really would like clarity at that moment. Prima facie at least, the "Except where ..." words quoted above mean that 9b prevails.

Separate point that I've found curious is that there is no size limit on the not-to-impede sailboat. In a narrow channel Mirabella 5 (M5 these days) and Maltese Falcon under sail (ok, that's unlikely I know!) are supposed to not impede a small motor boat. Whose bright idea was that? The rule writers have lost track also of how manoeuvrable a (say) 25m mobo is; it ought not to have special privileges
 
There is actually an answer to that question :) And I certainly agree that it's not easy to figure out just from the text of the Rules. It's been partially fixed by interpretation, and was clarified slightly with amendments to Rule 8. This particular question really puzzled me and I spent a lot of time on it a few years ago.

If you are required to "not impede" another vessel, it means you are supposed to maneuver in such a way that you don't interfere with the other vessels passage -- you do not create a situation which requires him to maneuver. For example, if you are crossing a TSS, you are supposed to plan your crossing so that you pass behind other traffic, or far enough ahead that it doesn't have to maneuver in case you're the stand-on vessel.
Is there evidence to back that up?

This one really confuses me because what you say is the usually accepted meaning of the words but it is hard to reconcile with the natural English interpretation of 8(f)(I). That can be read as saying that provided the vessel has sufficient room to manoeuvre safely then you are not obliged to take any further action.

I know at one point there was additional guidance but that it was dropped when those words were added.
 
Many thanks DH. That's a really helpful description, and I have struggled with this one a lot (I got interested in it when I was driving my 24m mobo up and down the Hamble:D:D). I agree your analysis, except that I am not sure you have dealt with the opening line of rule 18 "Except where Rules 9,10 and 13 otherwise require...". Are you saying that you think your description above is correct, even taking those opening words into account? How come? Why is 18(a)(iv) not subservient to 9b? I don't get that. I haven't got to bottom of this one nor studied case law so I'm definitely asking a question here rather than arguing against you

The problem is relevant because the "sailboat doesn't impede motorboat >20m" scenario is, in our daily lives, much more likely in a narrow channel (like Chichester in that video) than TSS. In a channel, anything more than 150m away is almost irrelevant and only very close boats are of interest, unlike the open sea. So risk of collision, the mobo's 18(a)(iv)obligation to keep clear of sail, and the sailboat's 9b obligation not to impede, all suddenly occur at the moment. And you really would like clarity at that moment. Prima facie at least, the "Except where ..." words quoted above mean that 9b prevails.

Separate point that I've found curious is that there is no size limit on the not-to-impede sailboat. In a narrow channel Mirabella 5 (M5 these days) and Maltese Falcon under sail (ok, that's unlikely I know!) are supposed to not impede a small motor boat. Whose bright idea was that? The rule writers have lost track also of how manoeuvrable a (say) 25m mobo is; it ought not to have special privileges

This is helpful on the "not impede" question:

"The IMO Subcommittee on Safety of Navigation for a time had issued guidance on the meaning of the term "shall not impede." That guidance said that the "shall not impede" command meant to maneuver, when practicable, so far out of the way of the other vessel that risk of collision never develops, with the proviso that if risk of collision by some chance does develop, the more general Steering and Sailing Rules would take over (that is, the "shall not impede" rules would no longer be in effect).

"The IMO subsequently decided that the guidance, if given at all, should be part of the Rules. During the course of the debate on the actual language, the delegates decided that the vessel that had been originally directed to not impede the other should retain that burden even after risk of collision arose. That does not mean, however, that the (usually larger) vessel that was not to be impeded continues to have the right of way. The new Rule provides that if the not-to-be-impeded vessel would be the give-way vessel under the general rules, it has the duty to stay out of the way of the impeding vessel after risk of collision arises. Under the new Rule, which changed the earlier official guidance in this respect, the impeding vessel also continues to have a duty to stay out of the way after risk of collision arises, and does not gain the stand-on status that the general rules might have given it. Both vessels would be obligated to stay out of the way."


http://navruleshandbook.com/Rule8.html

The "except where" phrase means that your 24 metre power boat is required to give way to sail once the sailor has failed to "not impede" you.

Bizarrely, he is also required to carry on "not impeding" you, but it's hard to see how practically he can stand-on and not impede at the same time. The comments say that the vessel which is supposed to "not impede" does not stand-on, but other authorities say otherwise - -because it is required for the give-way vessel to make an effective maneuver. What's right there I don't know.

I think the practical implication of all of this is that the sailboat should not be tacking up the channel at all if he sees a ship or >20 metre motor vessel coming up. He should get out of the channel, or heave-to and let the large motor vessel get by before carrying on sailing -- and he should do that well before the risk to collision arises. Perhaps a good shorthand for "not impede" is "stay well clear", which is different from giving way.


Why do the Rules require sailing vessels of all sizes to "not impede", and not just those under 20 metres? It's certainly deliberate, and I think it is exactly to cover this kind of case -- sailing vessels under sail of all sizes may have to tack or gybe or lose way in a lull. In order to prevent dangerous situations from arising in narrow channels, they should stay well clear of other traffic. If they're going to have to tack up a channel, they should wait until they can do so without interfering with traffic which can only maneuver in the narrow channel. That's how I interpret that.

P.S. -- one question I don't have an answer to, relevant to the original discussion, is whether the sailing vessel of whatever size is obligated to heave to and wait before tacking up the channel, if the traffic is <20 metres but unable to navigate outside the narrow channel, or another sailing vessel. Can the duty to "not impede" be mutual? I don't know. The NavRules comments above seem to imply that it can.
 
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Is there evidence to back that up?

This one really confuses me because what you say is the usually accepted meaning of the words but it is hard to reconcile with the natural English interpretation of 8(f)(I). That can be read as saying that provided the vessel has sufficient room to manoeuvre safely then you are not obliged to take any further action.

I know at one point there was additional guidance but that it was dropped when those words were added.

Yes, this is very confusing indeed.

See the comments linked to in my previous post, which are very helpful.
 
Yes, this is very confusing indeed.

See the comments linked to in my previous post, which are very helpful.
Bizarrely the guidance issued prior to the inclusion in the 1987(?) version was much clearer and stated pretty much explicitly what is now the generally accepted interpretation - but when they actually added that to the rules it took a different form that naturally seems to have a different interpretation. YOu have to ask why, if they meant to put the previous guidance into the rules didn't they add equivalent words rather than the much more ambiguous wording they adopted.
 
Bizarrely the guidance issued prior to the inclusion in the 1987(?) version was much clearer and stated pretty much explicitly what is now the generally accepted interpretation - but when they actually added that to the rules it took a different form that naturally seems to have a different interpretation. YOu have to ask why, if they meant to put the previous guidance into the rules didn't they add equivalent words rather than the much more ambiguous wording they adopted.

I agree!
 
What a curious idea. How do you think risks of collision arise?

Yes -- totally wrong phrase. Thanks for pointing it out.

I meant -- to create a dangerous situation unnecessarily. To create a risk of collision in such a way that the give-way vessel does not have time or searoom to plan and execute a maneuver in the ordinary course, with enough time to consider other traffic, etc.

This is a classical Rule 2 thing. One reason why you should not tack under the bows of another vessel, in such a way that the vessels are put into an in extremis position with each other, so that the other vessel has to make a crash stop or a desperate maneuver.

And you shouldn't do it even if the other vessel should not be where he is, because he should have been "not impeding" you, or because he was obligated to anticipate your tack.
 
Yes -- totally wrong phrase. Thanks for pointing it out.

I meant -- to create a dangerous situation unnecessarily. To create a risk of collision in such a way that the give-way vessel does not have time or searoom to plan and execute a maneuver in the ordinary course, with enough time to consider other traffic, etc.

This is a classical Rule 2 thing. One reason why you should not tack under the bows of another vessel, in such a way that the vessels are put into an in extremis position with each other, so that the other vessel has to make a crash stop or a desperate maneuver.

And you shouldn't do it even if the other vessel should not be where he is, because he should have been "not impeding" you, or because he was obligated to anticipate your tack.
I think if you are in a position to tack under someone's bows then we can say that risk of collision exists (and has for some time). In that case the obligations of both vessels is clearly (?) defined in Colregs so you don't need to rely on 2 to say that tacking under someone's bows for no reason is wrong. The exception would be in the case this thread starts with where the stand on vessel is obliged to tack because he has reached the edge of the channel or to avoid some other cause.

Of course put a 3rd vessel in the picture and things get a whole lot more complicated.
 
I think if you are in a position to tack under someone's bows then we can say that risk of collision exists (and has for some time). In that case the obligations of both vessels is clearly (?) defined in Colregs so you don't need to rely on 2 to say that tacking under someone's bows for no reason is wrong. The exception would be in the case this thread starts with where the stand on vessel is obliged to tack because he has reached the edge of the channel or to avoid some other cause.

Of course put a 3rd vessel in the picture and things get a whole lot more complicated.

What if two vessels are on parallel or diverging courses, and one of them tacks under the bows of the other?


But let's also go back to the narrow channel case -- do we all agree that a sailing vessel should not tack under the bows of another vessel coming up the channel, so close that a crash stop or hard maneuvers are required of the other vessel?
 
Thanks both
I'd like to think about the sailboat/mobo and narrow channel so more but for now it looks like this to me:

You have Llana and W telling us, I think, that the rules create a stand off. The sailboat is obliged not to impede the mobo; the mobo is required to give way to the sailboat because Rule 8f(iii) tells us that normal rules apply. If that is correct, the rules are profoundly crummy. it's like the highway code telling us to stop at both green and red traffic lights. What humans want is a rule telling the green light guy to go and the red light guy to stop. It's not hard.

But I'm not 100% convinced on Llana and W. 8f(iii) just says normal rules still apply to the not to be impeded vessel. Normal rules includes 18, which says steam gives way to sail, and includes the rule that 18 is itself subject to 9b, which says >20m sailboat must not impede steam boat in a channel. Heck. IF you interpret (I'll call it "JFM interpretation") the 9b do not impede obligation on the sailboat as trumping the steamboat's rule 18 obligation to keep clear (your authority for that being the opening line of rule 18) then at least you get some sense and a clear rule about who gives way and who carries on - like red-green traffic lights it now makes sense because you're clear that sailboat is give way. But I say "IF" - JFM interpretation isn't yet clear to me because the wording seems to lack the necessary clarity. Part of the case for JFM interpretation is that the alternative "L+W" interpretation leads to the following outcome:
  • 9b. sailboat must not impede, according to a rule that is superior to the next two below;
  • 17ai. Sailboat shall keep her course and speed;
  • 18+16. mobo must keep well clear of sailboat;
  • 8fiii. mobo is always subject to part B
Hmmm. What a mess! As a minimum, there is a conflict between the first two above. If there is a collision, it is always 50/50 blame because both boats must have breached their respective obligation. That surely makes the L+W interpretation questionable: the rules should at least allow the possibility of 100:0 blame in order to be fair. In old cases there were plenty of 100% blame allocations, and only the new 17b made that harder, but even 17b allows the possibility of a 100% blame allocation.

If you apply Roanoke and the cases and stories referred to in the full judgement, the sailboat's 17ai obligation broadly means doing whatever it sensibly and predictably should, including (as one judge explicitly said) movements to comply with Colregs, so including movements to comply with 9b. The mobo has a right and (perhaps) obligation to assume the sailboat will move so as not to impede (that movement being the stand on obligation of the sailboat, following roanoke). Accordingly the correct thing for mobo to do is carry on and not dodge the sailboat (until 17b bites, of course, but that's a different point so let's leave it out of the discussion). I think I prefer this JFM interpretation to L and W's but I want to think about it some more... open to other ideas.

I think it is unbeleivable crummy of Colregs to provide a non impedance right on the mobo in clear words, and reinforce it with the "18 is subservient to 9" words, then for IMO or whoever to issue stuff saying that actually, do you know what, the mobo must give way after all. Colregs need to produce red light/green light answers, with 17b backstop to stop people playing chicken
 
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But let's also go back to the narrow channel case -- do we all agree that a sailing vessel should not tack under the bows of another vessel coming up the channel, so close that a crash stop or hard maneuvers are required of the other vessel?
Assuming the tack is at the channel edge (an important assumption), then absolutely not! The sailboat's obligation is 17(a)(i) which means it can and even should tack. If a collision is certain then it would need under 17b to do something, like steer away or not tack in the first place, but 17b does not bite if the mobo can avoid the collision by a crash stop which I think is the fact pattern in your question.
I'm only saying what the rules say, not what is sensible! The sailboat is free not to tack in this exact scenario, if it chooses
 
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