Buoy identification - for the experts

Supertramp

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I've seen them up the Hamble and in the Stockholm Archipelago. Apart from that I don't recall seeing them, but then there's no reason to remember seeing them. I think it would be pretty excusable not to recognise one and it's not like you can leave it the wrong side.

I would be amazed if many people came to harm through not recognising one.
That is true, and in the era of GPS and electronic charts unlikely to lead to trouble. But worth understanding as in the example below a starboard course is considerably more challenging than the port one!
Screenshot_20231229_141557.jpg
 

capnsensible

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I've seen them up the Hamble and in the Stockholm Archipelago. Apart from that I don't recall seeing them, but then there's no reason to remember seeing them. I think it would be pretty excusable not to recognise one and it's not like you can leave it the wrong side.

I would be amazed if many people came to harm through not recognising one.
You will if you go up the wrong channel.....
 

rogerthebodger

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It's a preferred channel marker.

Also sometimes called bifurcation buoys

with the preferred channel indicated by the colour of the top colour

Red keep the buoy to your Port side (pass buoy to starboard)

Green keep buoy to your starboard side (pass buoy to Port)

bifurcation-buoy-hr-2.png
 

capnsensible

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You mean - where anyone with any sense would put a cardinal mark (eg Shotley Spit)?

A disadvantage of the red/green vanes is that they sit where the light has to go.

They look like a solution in search of a problem.
There are plenty of well lit preferred channel marks in many ports and harbours. The light sequence reserved for them is F2+1 either red or green. The shape of the buoy and top mark are for the main channel.

See NP 5011 chart symbols and abbreviations.

All buoyage is taught on the day skipper Theory and practical courses.
 

Laser310

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You mean - where anyone with any sense would put a cardinal mark (eg Shotley Spit)?

not necessarily

the cardinal buoy implies a danger.., whereas RGR and GRG only tell you that the channel is bifurcating, and one side is preferred; there might not be any danger between them

also, the cardinal buoy does not signify channels on either side, where as RGR and GRG do

there are regional variations in buoyage custom, beyond just A and B, and it's worth figuring them out. For example, in my experience, Cardinal marks are very uncommon in the USA.
 
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capnsensible

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I would write down the word 'bifurcating' on a pice of paper, screw it up and throw it in the nearest out bin.

On a dark and stormy night, in the rain, the question is 'that way or this way'. As always, lights, shapes and topmarks indicate your safe track.

There aren't that many!!
 

Mark-1

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You will if you go up the wrong channel.....

Well firstly if someone's not familiar they'll have a chart out.

Secondly, unless I'm missing something it's possible to go through either channel, it's just one is preferred. If there was a wrong channel they'd surely stick a red or green there.

Neeves is still alive and I've never heard of anyone else coming a cropper over a preferred channel mark.
 

Mark-1

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That is true, and in the era of GPS and electronic charts unlikely to lead to trouble. But worth understanding as in the example below a starboard course is considerably more challenging than the port one!
View attachment 169764

Surely the guy who made that chart up could have made up a slightly saner use of a GRG!?

My 7yo could come up with something better.
 

Mark-1

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not necessarily

the cardinal buoy implies a danger.., whereas RGR and GRG only tell you that the channel is bifurcating, and one side is preferred; there might not be any danger between them

also, the cardinal buoy does not signify channels on either side, where as RGR and GRG do

It's doesn't really matter but plenty of other places use a Cardinal in exactly that situation.

Doesn't really matter because the chart makes it clear what's going on but I'd personally prefer a cardinal there. Would feel a bit odd leaving a flashing green to port when going rock dodging into that anchorage.
 

Daydream believer

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You will if you go up the wrong channel.....
But one is the "Preferred" channel. It does not mean that the other is the "Wrong" channel. Just not as good as the other.
It's doesn't really matter but plenty of other places use a Cardinal in exactly that situation.

Doesn't really matter because the chart makes it clear what's going on but I'd personally prefer a cardinal there. Would feel a bit odd leaving a flashing green to port when going rock dodging into that anchorage.
One used to do something like that when going north into the sound of Kerran approaching Oban, until they got fed up with boats running aground on the bank in the middle. I believe they have revised the buoyage now.
 

Mark-1

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One used to do something like that when going north into the sound of Kerran approaching Oban, until they got fed up with boats running aground on the bank in the middle. I believe they have revised the buoyage now.

Yeah, there wasn't a preferred channel mark last time I was there, and that was before kids so at least 10 years.
 

capnsensible

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But one is the "Preferred" channel. It does not mean that the other is the "Wrong" channel. Just not as good as the other.

One used to do something like that when going north into the sound of Kerran approaching Oban, until they got fed up with boats running aground on the bank in the middle. I believe they have revised the buoyage now.
Cmon, it depends on the draft and size of your boat/ship. Of course there is a wrong channel. That's the whole point.

For an easy way to understand it, big ships use the preferred channel, little boats can use both.

Check your charts, make your pilotage plan!

Add and keep it simple.
 

dunedin

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But one is the "Preferred" channel. It does not mean that the other is the "Wrong" channel. Just not as good as the other.

One used to do something like that when going north into the sound of Kerran approaching Oban, until they got fed up with boats running aground on the bank in the middle. I believe they have revised the buoyage now.
Kerrera Sound inconveniently has the Ferry Rocks slap bang in the middle, and people used to get confused by the buoyage and go straight into them (possibly simply by forgetting the direction of buoyage in the channel).
A few years back they improved the buoyage by putting both red and green buoys close together on the preferred West channel and an East Cardinal on the east of the rocks.
No preferred channel buoys used. Indeed I personally couldn‘t name any place on West Scotland with such a buoy, but suspect somebody will be along shortly to correct me.
 

Mark-1

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Cmon, it depends on the draft and size of your boat/ship. Of course there is a wrong channel. That's the whole point.

For an easy way to understand it, big ships use the preferred channel, little boats can use both.

Check your charts, make your pilotage plan!

Add and keep it simple.

I've only ever seen a preferred channel marker where the reason for the preferred channel was rudimentary traffic management. It's clearly not (typically) based on size of vessel or there would be preferred channel markers all over busy places with shipping and small boats like the Solent.

If there's a wrong channel you'd jist use a red/green, that's what they're for.

Having said all that all any nav mark *really* does is mark a pin point on the chart so it doesn't really matter.
 
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