Channel Traffic Separation Zones.

[doug748]

A little while ago someone said that in the central channel area, between the English Channel Separation zone and the Dover Separation lanes, vessels were directed not to impede traffic proceeding up and down channel.

I confirmed this myself, to my complete satisfaction but have lost the reference. So maybe I dreamt it.

Can anyone dig out a link for this? Thanks.

 

[[70521]]

I just keep out of their way. They don't notice the loss of 1/2 a knot, for 10 mins, 2 miles from them.

 

[Lucky Duck]

Bit annoying from them if they had plotted a course to go behind you...

 

[Topcat47]

Broadly speaking, traffic tends to roll up and down the channel on the most direct course between the separation zones at Dover and the Casquettes. On the UK side, Portsmouth and Southampton are the main sources of traffic joining the zones and on the French side Cherbourg and Le Havre so you do get traffic outside these routes and even those following the direct route between them do spread out a bit. It's quite important, therefore, to know where you are in relation to these routes. Even if you have AIS it's no guarantee that a commercial vessel will "see" you and seeing them isn't the whole answer. When crossing, keep a good lookout. Keep commercial shipping monitored when you do see it, and always cross behind. I am advised by a ships' navigator to always turn to Starboard, even if the vessel is approaching from the Port Side and it means a turn of >180 degrees for you.

Works for me.

 

[johnalison]

You might well avoid the separation zones if crossing from the Solent or Brighton but as far as the yachtsman goes it is much the same except that you are not bound by the right angle rule.

 

[doug748]

Good stuff, thanks to all.
What I would like to trace is a link to something which I am sure I saw, unless I am going nuts. That is:

That boats crossing the main lines of traffic, in that sector, are requested to not impede ships transiting between the two separation zones

 

[laika]

So maybe I dreamt it.

If you mean, as I think you do, outside the separation zones on the line between the dover TSS and the off-casquets TSS...my money is on you having dreamt it.

 

[GHA]

Good stuff, thanks to all.
What I would like to trace is a link to something which I am sure I saw, unless I am going nuts. That is:

That boats crossing the main lines of traffic, in that sector, are requested to not impede ships transiting between the two separation zones

Charts have it as a recommended traffic lane and note below so maybe something in it >

HO Definition:RECOMMENDED TRAFFIC LANE PART. Recommended direction of traffic flow is a traffic flow pattern indicating a recommended directional movement of traffic where it is impractical or unnecessary to adopt an established direction of traffic flow. (IHO Dictionary –S-32).A recommended traffic lane part is an area of a recommended direction of traffic control area within which traffic flow is generally along one bearing.

 

[Topcat47]

If you mean, as I think you do, outside the separation zones on the line between the dover TSS and the off-casquets TSS...my money is on you having dreamt it.

About 5 years ago I was at an RIN meeting in Warsash discussing the interface between commercial vessels and leisure craft. The presentation was by an Ex RN officer, currently working commercially as a deck officer on a Tanker. Much of what he said rather assumed a quite sophisticated electronic navigation suite on the leisure craft. He was advising, for example, yachts taking avoiding action when the commercial vessel was around five miles distant as the ship might take 2 miles to alter course around it and later avoiding action might easily put the smaller craft in danger. It was pointed out to him that most small craft couldn't determine if a collision course was probable until the ship was much closer, using hand bearing compasses to ascertain the likelihood of a collision. He said then that current advice for leisure craft was not to impede ships in transit, and the safest course of action was to "run away".

Even if Snark were travelling at right angles to the general direction of traffic wrt compass course, the tide would have as big an effect on the course as the helm.

 

[doug748]

Charts have it as a recommended traffic lane and note below so maybe something in it >

HO Definition:RECOMMENDED TRAFFIC LANE PART. Recommended direction of traffic flow is a traffic flow pattern indicating a recommended directional movement of traffic where it is impractical or unnecessary to adopt an established direction of traffic flow. (IHO Dictionary –S-32).A recommended traffic lane part is an area of a recommended direction of traffic control area within which traffic flow is generally along one bearing.

Bingo, that must have been what it was.

Nothing to do with not impeding, thank you GHA.

 

[prv]

Much of what he said rather assumed a quite sophisticated electronic navigation suite on the leisure craft. He was advising, for example, yachts taking avoiding action when the commercial vessel was around five miles distant as the ship might take 2 miles to alter course around it and later avoiding action might easily put the smaller craft in danger. It was pointed out to him that most small craft couldn't determine if a collision course was probable until the ship was much closer, using hand bearing compasses to ascertain the likelihood of a collision.

For "quite sophisticated" read "an AIS receiver". Any yacht so equipped should be able to easily determine a risk of collision from five miles away - of course natural variations of the yacht's course and speed will have the CPA wobbling around at longer ranges, but that's why it's a risk of collision, not a definite prediction.

I realise that not all yachts have AIS receivers, but I also suspect that by this point those without are very much a minority in the Channel lanes.

Pete

 

[lw395]

..... always cross behind. I am advised by a ships' navigator to always turn to Starboard, even if the vessel is approaching from the Port Side and it means a turn of >180 degrees for you.

Works for me.

Seems like a great recipe for spending as long as possible in the lane and making it hard for the ships to understand WTF you are doing.

 

[GHA]

For "quite sophisticated" read "an AIS receiver". Any yacht so equipped should be able to easily determine a risk of collision from five miles away - of course natural variations of the yacht's course and speed will have the CPA wobbling around at longer ranges, but that's why it's a risk of collision, not a definite prediction.

I realise that not all yachts have AIS receivers, but I also suspect that by this point those without are very much a minority in the Channel lanes.

Pete

Also interesting that it's not unheard of for a CPA to be very close to exactly 1Nm with a ship a few miles away after he's done some collision avoidance

 

[Topcat47]

For "quite sophisticated" read "an AIS receiver". Any yacht so equipped should be able to easily determine a risk of collision from five miles away - of course natural variations of the yacht's course and speed will have the CPA wobbling around at longer ranges, but that's why it's a risk of collision, not a definite prediction.

I realise that not all yachts have AIS receivers, but I also suspect that by this point those without are very much a minority in the Channel lanes.

Pete

Not all commercial ships transmit and even if you gave a transponder rather than a receiver, there's no guarantee the bridge crew will be sufficiently awake to take notice.

 

[capnsensible]

Seems like a great recipe for spending as long as possible in the lane and making it hard for the ships to understand WTF you are doing.

Why would you think that?

If the traffic is crossing right to left, altering to starboard means they open quickly to the left so you can turn back across their stern and resume your course.

If the traffic is moving left to right, altering to starboard men's they open reasonably quickly to the right so you can turn back across their stern and resume your course.

Hey presto! You have not impeded, made you alteration clear so everyone understands and conformed with the rules.

It really is quite simple. :encouragement:

 

[prv]

Not all commercial ships transmit

In seven years of having an AIS receiver I've noticed exactly one commercial ship in the Channel which wasn't transmitting. Even that was three or four miles away at its closest point and it's possible that it was just a little weak and my receiver was having a bad day. I think those are pretty good odds.

even if you gave a transponder rather than a receiver, there's no guarantee the bridge crew will be sufficiently awake to take notice.

That has nothing to do with your post #9 nor the naval officer's advice in it, which is about the yacht monitoring the ship and not vice versa.

Pete

 

[jimbaerselman]

You might well avoid the separation zones if crossing from the Solent or Brighton but as far as the yachtsman goes it is much the same except that you are not bound by the right angle rule.

Agree.

For many years I've published a guide to crossing TIS. The guide takes into account the ambiguity which often arises in bad visibility when a sailboat crosses the second lane - coming from starboard. I wrote it after finding that almost all of my "nasty" moments occurred with vessels coming from starboard, and very few with vessels from port.

The guide has been criticised for ignoring the utility of AIS for resolving uncertain situations. But AIS is not universal.

Is it time to put more emphasis on communication?

JimB

 

[GHA]

Is it time to put more emphasis on communication?

The MCA aren't very keen >>

https://coastalsafety.com/radio-ais-guidance-uk-maritime-coastguard-agency-mca/

In 1995, the judge in a collision case said -“It is very probable that the use of VHF radio for conversation between these ships was a contributory cause of this collision, if only because it distracted the officers on watch from paying careful attention to their radar. I must repeat, in the hope that it will achieve some publicity, what I have said on previous occasions that any attempt to use VHF to agree the manner of passing is fraught with the danger of misunderstanding.


Marine Superintendents would be well advised to prohibit such use of VHF radio and to instruct their officers to comply with the Collision Regulations.”

Although the practice of using VHF radio as a collision avoidance aid may be resorted to on occasion, for example in pilotage waters, the risks described in this Note should be clearly understood and the COLREG complied with to their best possible extent.

 

[Topcat47]

In seven years of having an AIS receiver I've noticed exactly one commercial ship in the Channel which wasn't transmitting. Even that was three or four miles away at its closest point and it's possible that it was just a little weak and my receiver was having a bad day. I think those are pretty good odds.

That has nothing to do with your post #9 nor the naval officer's advice in it, which is about the yacht monitoring the ship and not vice versa.

Pete

A bit of Fred Drift occurred here. I didn't intend it to have a direct reference to my previous post. I just don't think it's a good idea to rely on AIS as your collision avoidance strategy. It only takes one ship to run you down. I don't know what you sail but I've had close encounters with commercial fishing vessels which were not transmitting AIS close to the french coast. I don't have it on my own boat, either. I can't be the only one.

 

[Topcat47]

The MCA aren't very keen >>

https://coastalsafety.com/radio-ais-guidance-uk-maritime-coastguard-agency-mca/

I have every reason to be grateful to the deck officers on both a Large Container Ship and a Condor Ferry, who shepherded me and my crippled craft through a sudden fog blank and monitored my progress cross channel until I was close enough to radio the coast guard. Their regular messages on the VHF were very comforting.