Colregs -- a question of interpretation?

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I was going to add something lengthy until I read Mariner69's response, which is exactly as I see things. I do in situations of uncertanty try to call up the other vessel on vhf. In more than one case it has confirmed we were seen and they were taking avoiding action but it was not visible at that stage by us. Had we turned to port the larger vessel would, or could have been a little busy on the bridge trying to understand what we were up to, had we seen him?

The legal side is interesting but I'd prefer to avoid it.
 
Have I got to attack from the Starboard side and is port a no, no.?

Though I did start the attack from port, I finished it up on starboard.

Is that ok??

The second ship. I only attacked from starboard, so I think that was Ok.
 
I'm the stand on, I'm the stand on, ooh dear I'm going to get cut in two.

This is where slavish following of the rule book will get you in trouble, the sailboat should have made a clear turn to port to pass behind the ferry.

Absolute stupidity and entirely the sailboat's fault in my opinion, as said before, throw rule book in sea where it belongs and keep your eyes open. This should have been prevented 100s of metres away by the sailboat turning to port in a very clear manner.

This sail over power thinking is even carried over by dinghys on the river and the number of times they reverse tack right in front of my bows at the last minute despite knowing I am within 10 feet of them. Idiotic behaviour.

 
I'm the stand on, I'm the stand on, ooh dear I'm going to get cut in two.

This is where slavish following of the rule book will get you in trouble, the sailboat should have made a clear turn to port to pass behind the ferry.

Absolute stupidity and entirely the sailboat's fault in my opinion, as said before, throw rule book in sea where it belongs and keep your eyes open. This should have been prevented 100s of metres away by the sailboat turning to port in a very clear manner.

This sail over power thinking is even carried over by dinghys on the river and the number of times they reverse tack right in front of my bows at the last minute despite knowing I am within 10 feet of them. Idiotic behaviour.

Did you link to the wrong video? If not, then your analysis of it is wrong on so many counts I don't know where to start!
 
Did you link to the wrong video? If not, then your analysis of it is wrong on so many counts I don't know where to start!

On closer ispection it appears that I require new specs :o

I thought the video perspective was that the sailboat was approaching from stbd and trying to cut in front of the ferry by steadfastly holding onto his stand on rights. Since the ferry may have been unable to manoeuvre quickly / might need to stay in channel and thus unable to turn to stbd in order to pass behind then it would have been prudent for the sailboat to think ahead and turn to port or slow down thus passing behind the ferry instead of maintaining his course and speed.

Of course in a head on situation both should turn slightly to stbd

Just pointing out that slavishly following the rules can bring calamity and prior planning is always best.
 
I'm the stand on, I'm the stand on, ooh dear I'm going to get cut in two.

This is where slavish following of the rule book will get you in trouble,
Please: if you don't know what the rule says, your contribution would be more valuable if you at least looked it up before you start discussing it.

In this instance, I thought I had made it really easy by including it in the first post of the thread:
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 manoeuvre 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 sub-paragraph (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.
Please look in particular at paragraphs 17(a)ii and 17b

Did you link to the wrong video? If not, then your analysis of it is wrong on so many counts I don't know where to start!
+1
I'm having problems working out which side of the ferry (?) we are looking from.
Assuming that the final few seconds are looking forward, then the yacht was approaching from (and hit) its port side, and was therefore the give way vessel. If he had "slavishly followed" the rules he would have altered to starboard to go round the stern much earlier, rather than altering course to port to try to get across its bows.
 
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The question is flawed, because there is no risk of collision at a distance of four miles unless you are either "Spirit of Australia" or an Aircraft Carrier.

At that distance, a course can be set to avoid the vessel completely, and interpretation of collision regulations is not required.

+1. Is the current argument just for arguments sake?
 
Surely the best course of action, as the stand on vessel and being a wee tidler would be to turn to starboard and go round in a circle, as previously stated.
But four miles is a long way, why not just slow down a little to pass astern or even, dare I say, a slight alteration to port (unnoticable) to pass astern of the large ship.
Just keep out of his way and avoid being a nusience
 
Surely the best course of action, as the stand on vessel and being a wee tidler would be to turn to starboard and go round in a circle, as previously stated.
But four miles is a long way, why not just slow down a little to pass astern or even, dare I say, a slight alteration to port (unnoticable) to pass astern of the large ship.
Just keep out of his way and avoid being a nusience

Well, thats what we all do..............But dont tell Tim.:)
 
Well, thats what we all do..............But dont tell Tim.:)
Can I just remind you (and others) that the question was "Can someone please offer an interpretation of Rule 17 that makes altering course to port to avoid a give way vessel legitimate?"

If "that's what we all do", it seems odd that so few people seem able to suggest an interpretation of the rules that would make it legitimate.

Or are you really saying that you don't give a damn about the rules? :eek:
 
Can I just remind you (and others) that the question was "Can someone please offer an interpretation of Rule 17 that makes altering course to port to avoid a give way vessel legitimate?"

If "that's what we all do", it seems odd that so few people seem able to suggest an interpretation of the rules that would make it legitimate.

Or are you really saying that you don't give a damn about the rules? :eek:


No, we are saying that, if we are more or less heading for the ship, lets say, a bit ahead, but then think, a bit to close. So we stop. the ship could not hit us if it tried and if we both turn to starboard, we remain on a colision course, forgetting the fact that we can change course, much faster than the ship. Whilst it might not be much of a problem for us to just go round in circles for a while. We have now sent the ship off on another direction, which could lead to a colision with some other vessel, less manuverable than ourselves. Or a sand bank.

The ship knows that tecnically, he is the give way vessel, but there is not alot he can do to resolve things. He also knows, that I can stop on a sixpence, or change direction in an instant. So he holds his course, so we know what action to take. So we may well drive up quite close, then stop, whilst he passes. Giving each other a cheary wave. Only about twenty yards away.

On the other hand, if the ship looks like it cannot be passed in front of easily.

We all go round the back.

There are no rules, that say, I must bow before the queen, or pay respects to a funeral, but we mostly do.

Common sence says, I pay alot of respect to 10,000 tons.
 
Can I just remind you (and others) that the question was "Can someone please offer an interpretation of Rule 17 that makes altering course to port to avoid a give way vessel legitimate?"

If "that's what we all do", it seems odd that so few people seem able to suggest an interpretation of the rules that would make it legitimate.

Or are you really saying that you don't give a damn about the rules? :eek:

I'll have a go , if I may Tim.
Haydn , I think your action is only the final option.


If you can just think about it, its just so obvious..........
Tim says the ships are giving way to us from 6-4 nm away, and altering course @ 4 miles away then I reckon they are out of our sight.

I dont think that I can see a ship 6 miles away and by the time I see him 1-2 miles away he has already altered course for me and as far as Im concerned he will miss me and I dont even notice him passing by on my horizon, in fact at 4-6 miles I cant even tell which kin way he is going.


Now by the time he is 1 mile away I can see him , he has already altered course and I now realize from Tims posts that he will have done (previously I was so naive I thought the captain was watching tv and it was fluke that he missed me ) .

So the answer is starring us all in the face.

we are all talking about a hypothetical situation, none of us will have ever actually found a ship bearing down on us on our port side as it will have altered course @ 6-4 miles before he was even in sight !

Tim has posed a hypothetical question, none of us will ever find a ship on collision course on our port side.

The situation can never arise.

Obviously if in the unlikely that a ship hasnt seen us and you ever do find one on a course that puts him in your uncomfort zone then you are free to act however you feel fit in order to avoid a collision including helming to port and astern of the ship.


This is a perfectly acceptable practice as long as there is no risk of collision.

a large ship @ 20 knots cant possibly turn 45 degrees as fast as we can do a 180 , so the safest place to be is close down his starboard side.


Tim, if you are right and the ships are avoiding us then the only time we need to take action is collision avoidance and we are not breaking any law in avoiding a collision in the best way we judge at the time.

Side of a ship is safe, a ship within a cable @20 knots aiming for our stern is scary, what happens if we foul a prop ?


I guess that some of the situations Haydn and others are describing are actually occurring at significantly closer quarters than you have in mind.
 
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just for clarity Tim, how close do you feel we should stand on ?

Do we wait until we can see if the deck hands are smoking ?

Whats the cut off point , when we can read ,

"warning smoking can damage your health" ?
 
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The answer to the question is fairly clear - The stand on vessel is allowed to alter course to port when the circumstances do not admit it to alter course to starboard, or to slow down or stop. The concomitant of this is that there will not be many circumstances where the stand on vessel is allowed to alter course to port.

Firstly, the reason the rules ask the stand on vessel not to alter to port, if the circumstances admit, is because the give way vessel is most likely to alter to starboard to avoid the impending collision. If one alters to starboard, and the other alters to port, a risk of collision is likely to remain.

Secondly, there are several reasons why a give way vessel may not alter course until later than "you" hope/expect..... They may have a policy of altering course at half a mile, or even a quarter mile, for a variety of reasons, whereas "you" get a bit jittery if they don't alter at a mile or two. Or they may have been asleep, or on the loo, or making a cup of tea and some toast, and only see you at a late stage - the natural reaction of a professional seaman is to alter to starboard. There may be other circumstances where they alter late.

In the event that they make their normal alteration to starboard, at the same time as "you" have decided to alter to port, the chances are that a new collision course will occur.

If there is truly a risk of collision, if the stand on vessel stops/slows significantly, or alters course to starboard, the chances of a new collision course being established are much less, even if the give way vessel chooses that moment to alter to starboard.

I would guess that a significant number of collisions occurred prior to the rule being created, where stand on vessels altered course to port, and the give way vessel altered course to starboard at much the same time.



However, "you" can do what you like until "you" deem a risk of collision to exist. Thus, you can be on a collision course with a "give way" vessel, but far enough away for a risk of collision not to exist yet, in which case, you can alter course to port with impunity. In this instance, what you are doing is avoiding/minimising the chances of a "risk of collision" occurring, rather than taking action to avoid a "collision". AFAIK, the rules say nothing about this.

IIRC there are many circumstances where you can be on a steady bearing with a vessel 4 miles away, but may not on a collision course. At 4 miles, bearings don't change very fast at seagoing speeds, and it is not until you are about 2 miles apart, that a bearing will start to change, or not, and it becomes clear that a risk of collision either exists, or does not exist.

(you can do some Maths on this to confirm the point at which the bearings start to change significantly at various spreads and relative headings, and I'm sure it will be as I suggest).

Again, IIRC, when I was officer of the watch of a "big ship", I didn't used to worry too much if a bearing didn't change until around the 2 mile point. If it was still steady at 2 miles, and I was the give way vessel, I would alter 30 degrees to starboard, and maintain that course until the other vessel was abeam.

The above applied in fairly open sea. In more crowded waters, I would have a greater tolerance and might not alter until a mile, or even less.

The upshot of the above is that you may not realistically be able to deem a risk of collision to exist until the other vessel is about 2 miles away. Thus, an alteration of course to port prior to 2 miles may not be an infringement of the rule - this doesn't legitimise the alteration to port under the rule, merely the rule doesn't yet apply.

I would hope that everyone here who makes the alteration to port as the stand on vessel, does so before a risk of collision is deemed to exist, and I am sure that is the case in most instances.

If you deem a risk of collision to exist, and you are the stand on vessel, you must stand on, and keep standing on, until you believe that the other vessel may not be taking appropriate action.

If you are of the type that insists on standing on, and standing on, and standing on, you can only do this until the point at which the other vessel can't avoid you by her actions alone, at which time you must take avoiding action.

In both of the above instances, you don't alter to port if there is an alternative - alter to starboard, slow down, stop, (I guess speed up could be appropriate in some circumstances)

A bit long and perhaps complicated, but the principle is fairly simple.
 
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just for clarity Tim, how close do you feel we should stand on ?

The real answer is that there is no definitive cut of point. It depends on the circumstances.

The rule says that, as the stand on vessel, you "may" take action if you feel that the give way vessel is not taking appropriate action.

In my long diatribe above, I suggest that it is difficult to establish risk of collision beyond 2 miles so, once you are the stand on vessel, you need to be pretty close before you "may " take action. IMHO by day, you will clearly be able to see that he is heading for a point ahead of you, in which case, my favoured option is to alter course to starboard by more than 90, to a point where I am running roughly parallel, or diverging slightly. If he is heading for a point ahead of you, and you turn a bit more than parallel with him, he will have to try very hard to hit you. If he hasn't seen you, he will hit the point you were both aiming at, and you will be nowhere near it. If he has seen you, and has a policy of altering very late, he will be watching you carefully, and will see you getting out of the way.

I guess there is the chance that, as you turn, he makes his turn to starboard. If he does this, he will have been planning to put you on his port bow, so you will be going away from him, and will see his bow cross your stern, (or both his red and green lights at night).

My real favoured option in a yacht, or mobo, is to take action to keep well out of the way of big ships..... If this means altering to port before risk of collision exists, so be it :)
 
I'll have a go , if I may Tim.
Haydn , I think your action is only the final option.


If you can just think about it, its just so obvious..........
Tim says the ships are giving way to us from 6-4 nm away, and altering course @ 4 miles away then I reckon they are out of our sight.

I dont think that I can see a ship 6 miles away and by the time I see him 1-2 miles away he has already altered course for me and as far as Im concerned he will miss me and I dont even notice him passing by on my horizon, in fact at 4-6 miles I cant even tell which kin way he is going.


Now by the time he is 1 mile away I can see him , he has already altered course and I now realize from Tims posts that he will have done (previously I was so naive I thought the captain was watching tv and it was fluke that he missed me ) .

So the answer is starring us all in the face.

we are all talking about a hypothetical situation, none of us will have ever actually found a ship bearing down on us on our port side as it will have altered course @ 6-4 miles before he was even in sight !

Tim has posed a hypothetical question, none of us will ever find a ship on collision course on our port side.

The situation can never arise.

Obviously if in the unlikely that a ship hasnt seen us and you ever do find one on a course that puts him in your uncomfort zone then you are free to act however you feel fit in order to avoid a collision including helming to port and astern of the ship.


This is a perfectly acceptable practice as long as there is no risk of collision.

a large ship @ 20 knots cant possibly turn 45 degrees as fast as we can do a 180 , so the safest place to be is close down his starboard side.


Tim, if you are right and the ships are avoiding us then the only time we need to take action is collision avoidance and we are not breaking any law in avoiding a collision in the best way we judge at the time.

Side of a ship is safe, a ship within a cable @20 knots aiming for our stern is scary, what happens if we foul a prop ?


I guess that some of the situations Haydn and others are describing are actually occurring at significantly closer quarters than you have in mind.

Yep, if the ship was going to change direction, it would have done it far before I got just a few hundred yards from it. I'm always on auto, so mostly going in a straight line. Maybe some ships, from miles away, changed course a bit, but I would not have known about them. Always we'd be on the fly, with the radar be low.

Haydn , I think your action is only the final option.


If you can just think about it, its just so obvious..........
Tim says the ships are giving way to us from 6-4 nm away, and altering course @ 4 miles away then I reckon they are out of our sight.

Yep suppose I could have picked them up on my radar, if downstairs. But was nearly always upstairs. Boat always on Track, auto pilot.

So tracking a straight line from say Plymouth to CI's.

How come the buggers come to attack me from my left. if Tim says they have 6/4 miles to change course, how come they are still all facing me.
 
You are driving a 12m motor cruiser in open water, at about 25 knots, and you see a ship approaching from your port side. By the time the range has reduced to about 4 miles, you are concerned that there is a risk of collision.

Based on other recent threads, it seems that many people would alter course a few degrees to port (I guess somewhere between 5 and 50 degrees).

Can someone please offer an interpretation of Rule 17 that makes altering course to port to avoid a give way vessel legitimate? Here is the rule. I've highlighted the bits that I see as being an issue in this case.

The scenario is deliberately based on the case law which established that the range at which, for want of a better term, Rule 17 comes into play is 6 miles. That was established in the nineteenth century, I think, and holds good for two vessels each of which perhaps takes a mile or more to turn or to take off all way.

If I were arguing the turn to port point (and ignoring the linguistic frailties of the drafting of the rule) I would suggest that 6 miles should not be taken to be a fixed distance in this context but a multiple of the vessels' concerned mean manoeuvring distance.

So, with a vessel which can turn or stop within 100 meters, 6 miles starts to look like a multiple of getting on for 100 rather than a multiple of six.

I appreciate that making such a distinction may currently not be enshrined in law. But, I believe that were it to be argued in a relevant case it would become so.

Actually, I have read a paper by Cockroft on similar lines but discussing the issue in the context of vessels of disparate speed rather than disparate size.

Some mathemeticians (Calvert etc) have, of course, suggested that the best way to avoid a collision is for both vessels to turn to starboard.
 
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