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Old 13-01-2016, 20:13   #136
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Re: Over-Reliance on AIS -- Collision off Dungeness

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Originally Posted by jackdale View Post
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 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.
It seems that the core of the controversy (or confusion) here lies in the second clause of Rule 17(a)(ii) (highlighted in red), which only allows a stand on vessel to alter course if the give way vessel is not altering course in a manner sufficient to avoid collision. Otherwise, Rule 17(a)(i) states that a stand on vessel "shall" keep her course & speed, so it's not optional. Given all the variables, it wouldn't be realistic for the Rules to specify actual distances when such a course alteration may occur, so the timing becomes a judgment call on the part of the stand on vessel, namely our sailboats in the scenario being discussed here (when under sail, that is, and the large ship isn't otherwise burdened).

In my case as I must admit, and with many other recreational sailors too it sounds, I have been altering course as the stand on vessel way too soon (after a risk of collision has arisen), and presumably long after the commercial (give way) vessel has already altered her course to avoid me. As has been stated, this can cause a large ship to alter course additional times, and potentially lead to confusion or worse.

But in the scenario being discussed, it does require you to presume that the large ship both knows you are there and is following the Rules. Should either presumption prove incorrect (as it inevitably will), however, the Rules also allow ample time, and in fact require the stand on vessel to alter course to avoid collision. So it hardly need turn into a game of "chicken," and that's obviously not what is intended.

It seems all too easy, and frankly more intuitive, to simply "make way for tonnage" in these scenarios, but the reality is by doing so you're violating the Rules, creating unnecessary unpredictability, and also making your boat into a WAFI in the eyes of professional mariners. I thought I had already "gotten it" by having a good comprehension of the Rules, but probably didn't realize until DH mentioned it how far out a properly functioning commercial ship can likely see me with their superior radar & other instruments. There was at least one memorable occasion, when sailing at night along the Carolina coast, that an overtaking merchant ship failed to see me, but a quick VHF call quickly resolved it after I picked the ship up on AIS. But generally, and in hindsight, I don't think I really "got it" until reading these discussions on CF, usually involving DH, Jack, Stu, MarkJ and others.

Many thanks!
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Old 13-01-2016, 23:20   #137
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Re: Over-Reliance on AIS -- Collision off Dungeness

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It seems all too easy, and frankly more intuitive, to simply "make way for tonnage" in these scenarios, but the reality is by doing so you're violating the Rules, creating unnecessary unpredictability, and also making your boat into a WAFI in the eyes of professional mariners.

:
This is what many do. And for those that sail in waters where traffic is light, you can get away with this and never know that you might be causing some grey hairs on the OOW head of a large commercial ship. Dockhead sails in the channel. I sail in Øresund. Take a look at the channel on Marine Traffic. The amount of ships being shown is staggering. Now add in all the smaller launches and yachts that are out there that don't have AIS (and therefore are not on the screen). This can bring a light sweat to your brow.

Now imagine doing this at night. To do this successfully you need to follow the colregs and you need to understand them. Otherwise you'll end up causing a heck of a lot of confusion.

One thing that has always bothered me (and this is a tip for you Dockhead on your coming billion dollar yacht)

Virtually every sailboat I have ever been on (including my own) has the VHF mounted under deck at the nav table - what is it doing there? By rights, it should be mounted up by the helm, or perhaps a repeater control panel and microphone should be mounted there. (does anyone make a VHF with a repeater panel function?

When we sail, we always have a handheld VHF at the helm. That way the helmsman can call approaching ships if necessary without leaving the helm. We have two of them -when the battery runs down on one, we simply switch it for the one that has been charging
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Old 13-01-2016, 23:30   #138
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Re: Over-Reliance on AIS -- Collision off Dungeness

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This is what many do. And for those that sail in waters where traffic is light, you can get away with this and never know that you might be causing some grey hairs on the OOW head of a large commercial ship. Dockhead sails in the channel. I sail in Øresund. Take a look at the channel on Marine Traffic. The amount of ships being shown is staggering. Now add in all the smaller launches and yachts that are out there that don't have AIS (and therefore are not on the screen). This can bring a light sweat to your brow.

Now imagine doing this at night. To do this successfully you need to follow the colregs and you need to understand them. Otherwise you'll end up causing a heck of a lot of confusion.

One thing that has always bothered me (and this is a tip for you Dockhead on your coming billion dollar yacht)

Virtually every sailboat I have ever been on (including my own) has the VHF mounted under deck at the nav table - what is it doing there? By rights, it should be mounted up by the helm, or perhaps a repeater control panel and microphone should be mounted there. (does anyone make a VHF with a repeater panel function?

When we sail, we always have a handheld VHF at the helm. That way the helmsman can call approaching ships if necessary without leaving the helm. We have two of them -when the battery runs down on one, we simply switch it for the one that has been charging
Raymarine and Icom for sure. I have worked with both. Raymarine on my own vessel with that setup. And I agree with you certainly. VHF capability at the helm is a must. Handhelds are ok at a pinch, but really lack the required distance, clarity and antenna visibility for good bridge/bridge comms.
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Old 13-01-2016, 23:45   #139
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Re: Over-Reliance on AIS -- Collision off Dungeness

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Originally Posted by Muckle Flugga View Post
Raymarine and Icom for sure. I have worked with both. Raymarine on my own vessel with that setup. And I agree with you certainly. VHF capability at the helm is a must. Handhelds are ok at a pinch, but really lack the required distance, clarity and antenna visibility for good bridge/bridge comms.
Agreed. I have an Icom M-604 at the nav station, but then what they call the "CommandMic" (or something like that) at the helm. This is wired to the main unit below and so has the exact same range & similar functions. Chartplotter, AIS & radar are also repeated at the helm on my boat, and I wouldn't want it any other way.
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Old 14-01-2016, 01:40   #140
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Re: Over-Reliance on AIS -- Collision off Dungeness

Quote:
Originally Posted by Exile View Post
It seems that the core of the controversy (or confusion) here lies in the second clause of Rule 17(a)(ii) (highlighted in red), which only allows a stand on vessel to alter course if the give way vessel is not altering course in a manner sufficient to avoid collision. Otherwise, Rule 17(a)(i) states that a stand on vessel "shall" keep her course & speed, so it's not optional. Given all the variables, it wouldn't be realistic for the Rules to specify actual distances when such a course alteration may occur, so the timing becomes a judgment call on the part of the stand on vessel, namely our sailboats in the scenario being discussed here (when under sail, that is, and the large ship isn't otherwise burdened).

In my case as I must admit, and with many other recreational sailors too it sounds, I have been altering course as the stand on vessel way too soon (after a risk of collision has arisen), and presumably long after the commercial (give way) vessel has already altered her course to avoid me. As has been stated, this can cause a large ship to alter course additional times, and potentially lead to confusion or worse.

But in the scenario being discussed, it does require you to presume that the large ship both knows you are there and is following the Rules. Should either presumption prove incorrect (as it inevitably will), however, the Rules also allow ample time, and in fact require the stand on vessel to alter course to avoid collision. So it hardly need turn into a game of "chicken," and that's obviously not what is intended.

It seems all too easy, and frankly more intuitive, to simply "make way for tonnage" in these scenarios, but the reality is by doing so you're violating the Rules, creating unnecessary unpredictability, and also making your boat into a WAFI in the eyes of professional mariners. I thought I had already "gotten it" by having a good comprehension of the Rules, but probably didn't realize until DH mentioned it how far out a properly functioning commercial ship can likely see me with their superior radar & other instruments. There was at least one memorable occasion, when sailing at night along the Carolina coast, that an overtaking merchant ship failed to see me, but a quick VHF call quickly resolved it after I picked the ship up on AIS. But generally, and in hindsight, I don't think I really "got it" until reading these discussions on CF, usually involving DH, Jack, Stu, MarkJ and others.

Many thanks!
I think this is very insightful.


It seems to me that "just make way for tonnage" is an attitude which is sometimes based on good intentions but lack of knowledge, and sometimes based on just laziness.

Another common mistake in all of this is the idea that standing on is some kind of privilege, and that there is something gracious in just giving up this "privilege".

I think a useful attitude is to consider standing to be, on the contrary, a burden, a kind of deference to the other vessel, whereas giving-way is really the privilege -- the privilege to control the crossing. It's the active role.

Certainly, I prefer the active role, and I am eager to take it, if it is offered to me. But you can't just grab it. You don't assume the other vessel sees you and has taken adequate action -- you simply give him a chance during that phase where you are obligated to do that. Once you've fulfilled that obligation, but only then, do you have the right to take over and start maneuvering yourself.

But to "earn" the right to take over the active role in a crossing, and start maneuvering yourself, you have to do one more thing, besides standing on for a while and giving him a chance to maneuver. You also are obligated to use adequate means to determine whether the ship has resolved the crossing, or not. You can't just assume at all times that there is a risk of collision, not having made the effort (and acquired the skill) to determine the real CPA, as someone advocated above.
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Old 14-01-2016, 02:04   #141
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Re: Over-Reliance on AIS -- Collision off Dungeness

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I think this is very insightful.


It seems to me that "just make way for tonnage" is an attitude which is sometimes based on good intentions but lack of knowledge, and sometimes based on just laziness.

Another common mistake in all of this is the idea that standing on is some kind of privilege, and that there is something gracious in just giving up this "privilege".

I think a useful attitude is to consider standing to be, on the contrary, a burden, a kind of deference to the other vessel, whereas giving-way is really the privilege -- the privilege to control the crossing. It's the active role.

Certainly, I prefer the active role, and I am eager to take it, if it is offered to me. But you can't just grab it. You don't assume the other vessel sees you and has taken adequate action -- you simply give him a chance during that phase where you are obligated to do that. Once you've fulfilled that obligation, but only then, do you have the right to take over and start maneuvering yourself.

But to "earn" the right to take over the active role in a crossing, and start maneuvering yourself, you have to do one more thing, besides standing on for a while and giving him a chance to maneuver. You also are obligated to use adequate means to determine whether the ship has resolved the crossing, or not. You can't just assume at all times that there is a risk of collision, not having made the effort (and acquired the skill) to determine the real CPA, as someone advocated above.
That is exactly how I view it and how I teach it. Both vessels are burdened with responsibilities the "stand on" vessel is actually the more constrained of the two, as its primary responsibility is to maintain course and speed. Therefore it is less free to manuever than the "give way" vessel. This is why I really can't stand the "right of way" brigade, who as you say consider their WAFI status to equate to some kind of privilege. I have lost count of the number of times I have heard some dumbass WAFI complain that the fishing vessel(s) they encountered "acted aggressively" and wouldn't acknowledge their "right of way"! Double
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Old 14-01-2016, 07:39   #142
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Re: Over-Reliance on AIS -- Collision off Dungeness

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That is exactly how I view it and how I teach it. Both vessels are burdened with responsibilities the "stand on" vessel is actually the more constrained of the two, as its primary responsibility is to maintain course and speed. Therefore it is less free to manuever than the "give way" vessel. This is why I really can't stand the "right of way" brigade, who as you say consider their WAFI status to equate to some kind of privilege. I have lost count of the number of times I have heard some dumbass WAFI complain that the fishing vessel(s) they encountered "acted aggressively" and wouldn't acknowledge their "right of way"! Double
I think the concept of "right of way" or "privilege" is another pretty common error for some. I was probably guilty of this too in my early days of big boat sailing. There was good focus on the Colregs themselves in the USCG course I took, but not really on how they are supposed to play out in actual practice. And the idea of a small sailboat "standing on" to a huge commercial vessel is quite counter-intuitive. The understandable but incorrect instinct is to get the hell out of the way! In fact, I used to think this was also just being "courteous" to the larger ship, like staying clear of big tractor-trailer trucks on the highway.

One sort of pedantic question: How would a commercial ship under these scenarios know that a sailing vessel is in fact under sail and therefore the stand on vessel? I almost always have some sail up, even when I'm only motoring, and of course I also motor-sail at times too. But any sort of engine propulsion renders us motor vessels, and therefore not subject to stand on status with the larger ship. This can be exacerbated at night, unless perhaps using your tricolor signals that you are under sail alone. Perhaps Class A AIS allows you to transmit this status, but not Class B I don't think (I have a receiver only). If in doubt, I suppose common sense & caution would prevail and a properly run merchant ship would just assume you are under sail. The relatively few times I've resorted to using the radio, I always make a point of identifying myself to the merchant ship as a sailing vessel under sail.
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Old 14-01-2016, 07:45   #143
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Re: Over-Reliance on AIS -- Collision off Dungeness

To answer the pedantic question, or attempt to.

There's that old chestnut of the inverted cone, but that's really difficult to see at any distance.

At night, it's easier, if sails are up and engine running, you'll be showing sidelight, mast head light (the white one) and a stern light, if sails only, no masthead light.

If the watchkeeper on the ship is also a proper sailor (can sail a boat), he/she) might figure it out, course and speed varying, or, has worked out that your heading with an AWA of 20 degrees.

In any case, if it was me, and was not sure, I'd give the sail boat the benefit of the doubt, and assume under sail.
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Old 14-01-2016, 07:57   #144
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Re: Over-Reliance on AIS -- Collision off Dungeness

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To answer the pedantic question, or attempt to.

There's that old chestnut of the inverted cone, but that's really difficult to see at any distance.

At night, it's easier, if sails are up and engine running, you'll be showing sidelight, mast head light (the white one) and a stern light, if sails only, no masthead light.

If the watchkeeper on the ship is also a proper sailor (can sail a boat), he/she) might figure it out, course and speed varying, or, has worked out that your heading with an AWA of 20 degrees.

In any case, if it was me, and was not sure, I'd give the sail boat the benefit of the doubt, and assume under sail.


Damn Nigel! you mean you can't spot my inverted triangle from 10nm out?

You're spoiling all the fun - now Jim and Ann Cate are gonna get on me saying "see - no reason to fly the damn thingy, they can't see it anyway!"

Bah! Humbug!
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Old 14-01-2016, 08:01   #145
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Re: Over-Reliance on AIS -- Collision off Dungeness

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To answer the pedantic question, or attempt to.

There's that old chestnut of the inverted cone, but that's really difficult to see at any distance.

At night, it's easier, if sails are up and engine running, you'll be showing sidelight, mast head light (the white one) and a stern light, if sails only, no masthead light.

If the watchkeeper on the ship is also a proper sailor (can sail a boat), he/she) might figure it out, course and speed varying, or, has worked out that your heading with an AWA of 20 degrees.

In any case, if it was me, and was not sure, I'd give the sail boat the benefit of the doubt, and assume under sail.
True meaning of an inverted cone: "Examining Instructor aboard and exam in progress."
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Old 14-01-2016, 08:12   #146
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Re: Over-Reliance on AIS -- Collision off Dungeness

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Raymarine and Icom for sure. I have worked with both. Raymarine on my own vessel with that setup. And I agree with you certainly. VHF capability at the helm is a must. Handhelds are ok at a pinch, but really lack the required distance, clarity and antenna visibility for good bridge/bridge comms.
When I sailed in the busy waters of the Channel, our VHF was below at the chart table with a cockpit speaker but no control microphone. Now, having completely re-troniced our latest boat we have a standard Horizon DSC VHF mounted below but with a 'command Mic' in the cockpit that controls all the functions even to switching on/off and DSC entries. It was both affordable and installable, even into the same hole in the nav table back panel where the original non DSC set sat.

That said in all my years of sailing in busy waters I avoided calling ships as so frequently I heard the confusion created by others trying to describe where they were and who they were calling. AIS has changed that confusion and that can only be for the good. AIS For sure is an excellent tool but is 'a' tool not 'the' tool, as in part of a full set but not exclusively, in place of it.

I really hope this discussion has opened a few minds and provided food for thought. There is a huge difference in small boat encounters with the big stuff in the open ocean than in areas of high concentration and the whole pattern of a giant interactive chess game. THe COLREGS have evolved over many years and study by many to re-evaluate where needed. They are the best we have, they are ( or should be) known by all BUT we ALL need to follow the rules for it to work, making arbitrary adjustments like give way to tonnage may seem plausible like a politicians instant knee jerk but are the short route to a potential disaster.

I consider it a privilege to have sailed and learned my craft in the English Channel waters now highlighted by Dockhead, it taught me navigation and collision avoidance techniques in all conditions, experiences that have stood me well. I'm not as clued up on space invaders as some afloat but understanding the evolution does mean I can use the modern stuff better than I might do otherwise. I did not have AIS until moving to the USA but did have radar and practiced it's use often in clear visibility to better understand it when it was essential in the fogs that sometime add to the confusion in the Channel. I still consider radar to be a more reliable tool than AIS for collision avoidance in poor visibility but the reality is that the one device compliments the other not eclipses it.

But well done indeed to Dockhead and others for giving the subject a decent airing!
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Old 14-01-2016, 08:16   #147
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Re: Over-Reliance on AIS -- Collision off Dungeness

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A hand bearing compass is not "bare eyes", and that's not what we were talking about. If you are skillful and diligent in the use of a HBC, then you can distinguish a collision course from a mile CPA from anyway 5 or 6 miles, and that is already something.
It may seem strange to you that seem to rely on electronics to avoid collision but on 95% of the cases you don't need any bearing compass to take a meaningful bearing on this case.

The bearing in degrees is irrelevant what is relevant is if the bearing is constant or not. If it is (approximately) constant then you may be on a collision course, if the boat moves ahead regarding the bearing it is going to pass ahead, if it moves backward than it is going to pass on your stern.

You just need not to move your head, take as reference some fixed part of the boat maintain a steady course and take bearings some minutes apart regarding the position of the ship and that fixed part of boat that serves you as marker.

Only if I had doubts (very few occasions) I use my binoculars and the compass inside for a more precise bearing.
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Old 14-01-2016, 08:21   #148
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Re: Over-Reliance on AIS -- Collision off Dungeness

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....

The perception of when risk of collision would be seen to exist all depends on location, traffic density, status of the vessels, speed etc.

Deep sea, on a large tug, not hampered by a tow, if I was the give way vessel, I would make a course alteration as soon as the risk had been determined (within reason, not at 60 nm separation, but more like somewhere between 5 to 10 miles out)

In waters like the Dover Straits, things get a lot different. ..At 5 miles out, would be looking at avoidance manoeuvres if needed, and the impact on other vessels if we alter course. Course alteration might be made as close as 2 miles away, with the intention of maintaining CPA's of at least 0.5 nm.
.....
And, like in all professions, there is good and bad, and hopefully bad is a small minority, but I must admit, I do share concerns about OOW believing in the infallibility of electronic aids, and failing to use their eyes and common sense.
Thanks regarding your clarification
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Old 14-01-2016, 08:25   #149
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Re: Over-Reliance on AIS -- Collision off Dungeness

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True meaning of an inverted cone: "Examining Instructor aboard and exam in progress."
+1

Although I do fly it when motorsailing
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Old 14-01-2016, 08:46   #150
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Re: Over-Reliance on AIS -- Collision off Dungeness

Here is a great example why you eye is bloody useless by itself, or even 2 of them.
Just being sitting in the cockpit with a tall ship captain looking at 3 boats, anchored, and asking which of the 3 is closest and which is further away.

OK, its more difficult to do it by photo, but...

Hull colour, like light brightness can make distance perception inaccurate.

Here, 2 grey boats look further away than the white.
Size also makes the larger one look closer.

So how much difference is range important?

Here the boats that appear further away are 500 meters/yards closer.
The closest boat is .73nm from me, Eclipse is 1nm from me. So neither are far off at all.

You can only tell by electronics. Your eye is as stuffed as mine


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