Colregs Puzzle

Dockhead

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We've had a fantastic brawl over on Cruisers Forum about one particular fine point of the Colregs -- namely whether the obligation the "not impede" a vessel navigating in a narrow channel, and unable to safely navigate outside it, under Rule 9, means that you must not stand on in case the situation evolves into a collision risk and thus getting Rule 18(a) into play.

Some people think that you still have to stand on, even if you're burdened by Rule 9, and there is a hint of some authority for that position in Cockcroft's rather authoritative book.

I have tracked down the great man himself and want to submit the question to him, as well as to the MCA and the RYA legal department, to try to get some authoritative guidance on this perplexing question.

I think this forum has a higher percentage of really knowledgeable people on Colregs questions, and I even read some comments on here by some authors of books on the subject. Does anyone care to comment on the problem as I have written it up, before I submit it to the aforementioned authorities? The draft text follows. Cheers, Dockhead





Situation:

A large commercial vessel is navigating in a narrow channel, and cannot safely navigate outside of it.

A sailing vessel is approaching on an intersecting course.

Rule 9(b) says that a vessel of less than 20 meters or a sailing vessel must “not impede” the passage of a vessel navigating in a narrow channel, which cannot navigate outside of it. Rule 9 applies in all conditions of visibility, and I think we know from various commentaries that the obligation to “not impede” means that the sailing vessel must maneuver in such a way to ensure that the situation does not develop to the point that a risk of collision arises in the first place.

But what happens if, for whatever reason, a risk of collision does develop? How does Rule 9(b) interact with Rule 18(a), which requires a motor vessel to “keep out of the way” of a sailing vessel, once the vessels are in sight of each other and a risk of collision exists? Does the obligation on the part of the sailing vessel to “not impede” negate the obligation of the motor vessel to “keep out of the way”? What is the priority between these obligations, or how do they interact?

Rule 18 starts with the phrase “Except where Rules 9 . . . otherwise require. . . .” That phase would seem to subordinate Rule 18 to Rule 9, so that the sailing vessel would not stand-on as would be otherwise required by Rule 18(a) (whether or not the motor vessel would nevertheless give way is a different question; discussed below). Instead, the sailing vessel would continue to attempt to avoid “impeding” the motor vessel, and would be obligated to maneuver out of the way. Maneuvering out of the way cannot be done simultaneously with standing on, so it would seem that the sailing vessel would at no point in such an encounter have any right or any obligation to stand on.

This interpretation is supported by Llana & Wisneskey, Navrules Handbook, Third Online Edition, http://navruleshandbook.com/index.html. In the commentary to Rule 9, they write:

Rule 8(f) "shall not impede" language is operative here. If your vessel is directed not to impede another, try to avoid causing the other vessel to change its course or speed. If you blunder into a risk-of-collision situation, the general Steering and Sailing Rules will not apply to you--you will continue to be obliged to stay out of the way. Be mindful, however, that Rule 8(f)(iii) says that the general rules will apply to the vessel you are impeding.
http://navruleshandbook.com/Rule9.html

That the sailing vessel’s obligation to “not impede” would continue to exist after a risk of collision comes into being would also seem to be fairly clear from the plan text of Rule 8(f)(ii):

A vessel required not to impede the passage or safe passage of another vessel is not relieved of this obligation if approaching the other vessel so as to involve the risk of collision and shall, when taking action, have full regard to the action which may be required by the Rules of this part.
Colregs, Rule 8(f)(ii)

But in A Guide to the Collision Avoidance Rules, AN Cockcroft & JNF Lameijer, 7th Ed., 2011, page 60, it is written that:

Rule 8(f)(ii) establishes clearly that a vessel required not to impede does not lose that obligation if approaching the other vessel so as to involve risk of collision. Although the other vessel may become the give-way vessel when risk of collision develops the vessel required not to impede is not relieved from the requirement to allow sufficient sea room for the safe passage of the other vessel because of the application of Rule 17(a)(i). Early action in compliance with Rule 8(f) is compatible with Rule 17(a)(ii), which permits action by the stand-on vessel (see pages 106-8).[Emphasis added.]

This implies that, on the contrary, the sailing vessel in our hypothetical case is the stand-on vessel under Rule 8(f), notwithstanding the continuation of its obligation to “not impede” under Rule 9.

One member of our Forum suggested the following:

1. We know that according to Rule 8(f)(iii) the motor vessel is obligated to give way under Rule 18(a) despite the obligation of the sailing vessel to “not impede”. This is uncontroversial. There cannot be giving way without standing on, so logically, the sailing vessel must stand on to the extent it can consistent with its obligations under Rule 9 and under Rule 17(a)(ii).

2. Rule 9 requires the sailing vessel to give the motor vessel enough sea room to fulfill its obligations to give way under Rule 18(a).

Others consider the idea of “not impeding” and simultaneously standing on to be logically impossible and absurd.
 
...

Rule 8(f)(ii) establishes clearly that a vessel required not to impede does not lose that obligation if approaching the other vessel so as to involve risk of collision. Although the other vessel may become the give-way vessel when risk of collision develops the vessel required not to impede is not relieved from the requirement to allow sufficient sea room for the safe passage of the other vessel because of the application of Rule 17(a)(i). Early action in compliance with Rule 8(f) is compatible with Rule 17(a)(ii), which permits action by the stand-on vessel (see pages 106-8).[Emphasis added.]

This implies that, on the contrary, the sailing vessel in our hypothetical case is the stand-on vessel under Rule 8(f), notwithstanding the continuation of its obligation to “not impede” under Rule 9.
....

Sorry, I don't see that is implied at all.
It just says that the vessel not to be impeded has obligations under R8, actions to avoid a collision. I don't see that this makes the other vessel 'stand on'
How can the sailing vessel be stand on when 8f (ii) directly states it is not relieved of the obligation to 'not impede'?


But remember, in 50% of encounters in a narrow channel, Rules 13 trumps everything, almost.....
 
Sorry, I don't see that is implied at all.
It just says that the vessel not to be impeded has obligations under R8, actions to avoid a collision. I don't see that this makes the other vessel 'stand on'
How can the sailing vessel be stand on when 8f (ii) directly states it is not relieved of the obligation to 'not impede'?


That is pretty much my logic too -- if the sailing vessel must not impede, how can he stand on? But others, including perhaps Cockcroft, disagree.
 
I don't really understand the dilemma.

A small sailing vessel a few hundred metres away from a large tanker could think he is the stand on vessel all he likes, but the fact is the tanker cannot steer away or stop in time to avoid the sailing vessel, so the sailing vessel had better b***dy well get out of the way.

End of.

Common sense applies - so does Darwin. Philosophising about who is right and wrong doesn't achieve much.
 
I don't really understand the dilemma.

A small sailing vessel a few hundred metres away from a large tanker could think he is the stand on vessel all he likes, but the fact is the tanker cannot steer away or stop in time to avoid the sailing vessel, so the sailing vessel had better b***dy well get out of the way.

End of.

Common sense applies - so does Darwin. Philosophising about who is right and wrong doesn't achieve much.

+1

I've always adopted the principle that if it's bigger than you its easier and safer to stay out of the way.
 
Common sense applies - so does Darwin. Philosophising about who is right and wrong doesn't achieve much.

No argument there. But some of us feel like it is important to really understand the Colregs. Consider it a chess problem if you like. I think that the rules actually mandate the same thing as common sense in this case, but I'm having a bit of trouble proving it.
 
No argument there. But some of us feel like it is important to really understand the Colregs. Consider it a chess problem if you like. I think that the rules actually mandate the same thing as common sense in this case, but I'm having a bit of trouble proving it.

The proof is, hang around in a narrow channel in your sailing dinghy in calm weather in the solent, and wait for a large tanker or container ship to come along. You'll soon have all the evidence you need.

PS, take a spare pair of trousers and a PLB :D
 
OMG. The trouble with endlessly arguing the toss about Col Regs is that you loose sight of why they are there: to help avoid collisions and they do so by being basically simple. If you try to adopt a lawyer type approach to them rather than the common sense one of keeping your little boat out of the way of the big one, you're simply asking for trouble.....
 
OMG. The trouble with endlessly arguing the toss about Col Regs is that you loose sight of why they are there: to help avoid collisions and they do so by being basically simple. If you try to adopt a lawyer type approach to them rather than the common sense one of keeping your little boat out of the way of the big one, you're simply asking for trouble.....

I am not sure that the Colregs are "basically simple", certainly not on this point.

I think it can be argued pretty well that just "keeping your little boat out of the way of the big one" can land you in a lot of trouble, if you willfully ignore the Colregs dance, and especially, if you can't identify a collision risk from a safe distance. If you encounter "big boats" travelling at speed in open water you actually need to know a great deal more than just "keep the little boat out of the way."

But that's not really the subject here, and no one is proposing ignoring common sense (not even the Colregs themselves). It is a probe into the true meaning of these points, for whatever it may or may not be worth to anyone. This is about the rules themselves, not collision avoidance per se.
 
For one thing, I don't see the absolute logic in 'if there is a give way vessel, the other must be stand on'
The case of two vessel approaching head on is an example of both vessels being required to give way.

I think 8 f (iii) merely states that a vessel not to be impeded is subject to all the rules of Part B, e.g R5 keeping look out, R6 safe speed,R7 determine risk of collision, R8 actions to avoid a collision through to R19 conduct in restricted visibility.
Just because you are stand on vessel, you are not relieved of many obligations.

Same as in the RRS, the right of way vessel has a bucket load of obligations and is required to avoid sinking the keep clear boat.
 
This question arises every time the subject of crossing TSS's arises - do a search, it's one of our perennials.

As you suggest, on occasion the "authorities" have been consulted by forum representatives, but both MCA and HMCG have been reported as declining to provide an exact definition of "impede".

Some people think that rule 9 amounts to an obligation on the small boat to give way in restricted channels. But others, myself included, argue that if that is what the rules meant, they would say so. One may stand on and still not impede a large ship that can readily and safely give way. But of course, you would need to be in direct communication with the ship, to be quite certain that you would not impede them by standing on. There is no excuse for WAFI's who chance it.

In practice, many ships in TSS's (and other restricted channels) do give way to small boats when required to do so under rule 18(a), often by small course adjustments even before the small boat is aware that risk of collision exists.
 
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Others consider the idea of “not impeding” and simultaneously standing on to be logically impossible and absurd.

I belong in the others group:)
I think that the sailing vessel would get the full blame in a case like this.

Here is my reasoning

Rule 8

(f)
(i) A vessel which, by any of these rules, is required not to impede the passage or safe passage of another vessel shall, when required by the circumstances of the case, take early action to allow sufficient sea room for the safe passage of the other vessel.
(ii) A vessel required not to impede the passage or safe passage of another vessel is not relieved of this obligation if approaching the other vessel so as to involve risk of collision and shall, when taking action, have full regard to the action which may be required by the rules of this part.
(iii) A vessel, the passage of which is not to be impeded remains fully obliged to comply with the rules of this part when the two vessels are approaching one another so as to involve risk of collision.

This part refers to Part B (rule 4 - rule 19)


To me it's clear the rule to consider her is 17 (a)(ii), (b) and (d)

I include rule 16 and 17 here for completness.
The purpose of rule 17(b) is to make it clear that there is no right to collide in the rules and all vessels must do what they can to avoid collision.

In this case the Give-way Vessel would in most cases be unable to do anything to avoid collision.

Rule 16 - Action by Give-way Vessel
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.

Rule 17- Action by Stand-on Vessel
(a)
(i) Where one of two vessels is to keep out of the way, the other shall keep her course and speed.
(ii) The latter vessel may however take action to avoid collision by her maneuver alone, as soon as it becomes apparent to her that the vessel required to keep out of the way is not taking appropriate action in compliance with these Rules.

(b) When, from any cause, the vessel required to keep her course and speed finds herself so close that collision cannot be avoided by the action of the give-way vessel alone, she shall take such action as will best aid to avoid collision.

(c) A power-driven vessel which takes action in a crossing situation in accordance with subparagraph (a)(ii) of this Rule to avoid collision with another power-driven vessel shall, if the circumstances of the case admit, not alter course to port for a vessel on her own port side.

(d) This Rule does not relieve the give-way vessel of her obligation to keep out of the way.

No evidence that breaking a rule give you "Stand-on Vessel" status.
 
No argument there. But some of us feel like it is important to really understand the Colregs. Consider it a chess problem if you like. I think that the rules actually mandate the same thing as common sense in this case, but I'm having a bit of trouble proving it.

I a afraid that while you are cogitating and wondering the skipper of the tanker/container ship is quite clear in his mind that hat you are not going to be daft enough to impede him so will continue along his side of the channel as if on railway lines and if you are daft enough to sail into the wind shadow ahead of him and catch you mast and rigging on his anchor hanging ready to drop then best of luck . Harbour rules possibly come into play as well. No doubt the ship will sound many blasts of the whistle to remind you he is there.

The ship could be drawing up to 10 metres in 12 metres of water . The piddly wee yacht may only need a paltry metres and can sail outside of the channel. No contest.
 
I belong in the others group:)
I think that the sailing vessel would get the full blame in a case like this.

Here is my reasoning



This part refers to Part B (rule 4 - rule 19)


To me it's clear the rule to consider her is 17 (a)(ii), (b) and (d)

I include rule 16 and 17 here for completness.
The purpose of rule 17(b) is to make it clear that there is no right to collide in the rules and all vessels must do what they can to avoid collision.

In this case the Give-way Vessel would in most cases be unable to do anything to avoid collision.



No evidence that breaking a rule give you "Stand-on Vessel" status.

I think everyone would agree with you once you get to a 17(b) situation. The question is what happens prior to that -- after a risk of collision exists but prior to an imminent collision which cannot be avoided unless the stand-on vessel maneuvers.
 
I a afraid that while you are cogitating and wondering the skipper of the tanker/container ship is quite clear in his mind that hat you are not going to be daft enough to impede him so will continue along his side of the channel as if on railway lines and if you are daft enough to sail into the wind shadow ahead of him and catch you mast and rigging on his anchor hanging ready to drop then best of luck . Harbour rules possibly come into play as well. No doubt the ship will sound many blasts of the whistle to remind you he is there.

The ship could be drawing up to 10 metres in 12 metres of water . The piddly wee yacht may only need a paltry metres and can sail outside of the channel. No contest.

Definitely true.

But that is not the question here. And the point of this is to get the cogitating out of the way while we're behind our computer screens, so that we don't have to do any behind the helm :)
 
I don't really understand the dilemma.

A small sailing vessel a few hundred metres away from a large tanker could think he is the stand on vessel all he likes, but the fact is the tanker cannot steer away or stop in time to avoid the sailing vessel, so the sailing vessel had better b***dy well get out of the way.

End of.

Common sense applies - so does Darwin. Philosophising about who is right and wrong doesn't achieve much.

If everyone was a pragmatic as this, people with nothing better to do would no longer be able to discuss hypothetical nonsense questions till the cows come home.

Where is your sense of fun?
 
This question arises every time the subject of crossing TSS's arises - do a search, it's one of our perennials.

As you suggest, on occasion the "authorities" have been consulted by forum representatives, but both MCA and HMCG have been reported as declining to provide an exact definition of "impede".

Some people think that rule 9 amounts to an obligation on the small boat to give way in restricted channels. But others, myself included, argue that if that is what the rules meant, they would say so. One may stand on and still not impede a large ship that can readily and safely give way. But of course, you would need to be in direct communication with the ship, to be quite certain that you would not impede them by standing on. There is no excuse for WAFI's who chance it.

In practice, many ships in TSS's (and other restricted channels) do give way to small boats when required to do so under rule 18(a), often by small course adjustments even before the small boat is aware that risk of collision exists.

Interesting post. It seems to me that "not impeding" means you don't do anything which would cause the vessel which you are required to "not impede" to maneuver. If he has to maneuver, you are impeding him, wouldn't you think so? It seems entirely logical to me.

But some have argued this very thing.
 
Quite. Nobody can cause a collision by giving way, just make it clear that is what you are doing.

It's not at all on the topic, but au contraire -- you can definitely cause a collision by giving way -- in the wrong direction, or at the wrong time.

See for example:

"A stand-on vessel which takes avoiding action before it can reasonably be
assumed that the give-way vessel is not taking appropriate action is likely to be held mainly to blame if practically simultaneous action by the give-way vessel causes a confused situation which results in collision."


A Guide to the Collision Avoidance Rules, AN Cockcroft & JNF Lameijer, 7th Ed., 2011, page 108.

You're not really allowed to just give way willy-nilly, whenever you feel like it. It is not inevitably harmless.
 
No argument there. But some of us feel like it is important to really understand the Colregs. Consider it a chess problem if you like. I think that the rules actually mandate the same thing as common sense in this case, but I'm having a bit of trouble proving it.

FFS, it's dead simple, Wood gives way to GRP & GRP gives way to steel, especially when they are stonkin' great lumps of steel.

Your esoteric nonsense has as much link to reality as the discussion of whether fairies exist (& that is not a euphemism for homosexuals). How hard is it to go round the back of another boat & make your intentions clear as soon as you spot any potential risk?

Simply avoid all situatiions where the colregs might need to be discussed rather than be blindingly obvious! It is a simple survival strategy & avoiding potential collision situations is the first step to becoming an Ancient Mariner.
 
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