Crossing Shipping Lanes

So, after 100 replies to my question about how to cross TSS....

One thing seems certain - there is absolutely no consensus on how to interpret Colregs, with some posters not even following Colregs but using there own tried and tested techniques.

Interesting to speculate if the problem is poor wording of the Colregs or the just the difficult nature of a finding a reliable system to 'allow frogs to safely cross motorways', or both.

Many thanks for stimulating comments and advice from all.
 
So, after 100 replies to my question about how to cross TSS....

Paul

Out of interest, was your original question a theoretical one or a genuine "I'm about to do it"?

I cross the Channel regularly, taking on the shipping lanes each time. But I can easily avoid any TSS (in compliance with 10c/10h) because my route is typically one end of the IoW to France or the CI. Only rarely would the rhumb line of my ideal route take me into a TSS (e.g. The Off Casquets TSS when doing Guernsey to Weymouth) and that calls for a minor diversion to avoid it.

For those whose boats are berthed between Brighton and Dover, there isn't really an option to avoid a TSS altogether if wanting to cross the Channel, without a fairly lengthy diversion.

Of course, if you never enter a TSS then the question of what exactly is meant by "shall not impede" never arises. :o
 
Thanks Angela, it's theoretical, at least for a couple of years. Although I guess I may shave the Scillies one later in the year.
 
Since there are so many opinions in this thread, and all with some merit, I thought I'd add mine.
The IRPCAS or Colregs are not the 'Navigating in Open Water' regulations. They only come into play in a collision situation. If I am sailing south and there's a large ship five or six miles away heading west (making me the stand-on vessel in a collision situation) and I, judging that in an hour or so, either by eye or AIS that we will be too close for comfort, alter course 45degrees to port so as to avoid a collision situation altogether, I am not infringing the Colregs. That's just prudent navigation. If I do this at the range stated, I won't yet be in a TSS. The manoeuvre if correctly judged will allow me to cross the TSS correctly, or pass behind the vessel in open water.
Should I judge that I can pass ahead, but in an hour find my judgement faulty, the Colregs apply, and I should hold my course, being the stand-on vessel. If it looks as though a collision is still likely, i.e. the other vessel does not appear to be altering course (and it's my judgement that counts here) I am obligedto avoid a collision. Perhaps the best manoeuvre here is a 90 degree turn to Starboard.
In the specific case of crossing a TSS, I aim to arrive at the edge of it at a suitable time and place so that I can cross without troubling the biggies in any way. It's really not that difficult, or that different from the 'shipping lanes'. The major difference is to make your heading 90 degrees to the direction of travel.
 
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Confusing isn't it? However, just an additional note of caution - big ships may not be keeping a good lookout and/or may not see a small yacht. Have a look at the MAIB website and you'll get the idea.
 
Since there are so many opinions in this thread, and all with some merit, I thought I'd add mine.
The IRPCAS or Colregs are not the 'Navigating in Open Water' regulations. They only come into play in a collision situation. If I am sailing south and there's a large ship five or six miles away heading west (making me the stand-on vessel in a collision situation) and I, judging that in an hour or so, either by eye or AIS that we will be too close for comfort, alter course 45degrees to port so as to avoid a collision situation altogether, I am not infringing the Colregs. That's just prudent navigation. If I do this at the range stated, I won't yet be in a TSS. The manoeuvre if correctly judged will allow me to cross the TSS correctly, or pass behind the vessel in open water.
Should I judge that I can pass ahead, but in an hour find my judgement faulty, the Colregs apply, and I should hold my course, being the stand-on vessel. If it looks as though a collision is still likely, i.e. the other vessel does not appear to be altering course (and it's my judgement that counts here) I am obligedto avoid a collision. Perhaps the best manoeuvre here is a 90 degree turn to Starboard.
In the specific case of crossing a TSS, I aim to arrive at the edge of it at a suitable time and place so that I can cross without troubling the biggies in any way. It's really not that difficult, or that different from the 'shipping lanes'. The major difference is to make your heading 90 degrees to the direction of travel.

I'm not convinced. :)

If you and the other vessel will be in a passing situation in an hour's time but your calculation is wrong and it tramspires that crossing is too close, then you will have been in a confirmed collision situation long before the hour had passed so ColRegs would have applied much earlier than you are suggesting.

Richard
 
I'm not convinced. :)

If you and the other vessel will be in a passing situation in an hour's time but your calculation is wrong and it tramspires that crossing is too close, then you will have been in a confirmed collision situation long before the hour had passed so ColRegs would have applied much earlier than you are suggesting.

Richard

ColRegs cannot possibly be relevant to anything you do not know.
 
I'm not convinced. :)

If you and the other vessel will be in a passing situation in an hour's time but your calculation is wrong and it tramspires that crossing is too close, then you will have been in a confirmed collision situation long before the hour had passed so ColRegs would have applied much earlier than you are suggesting.

Richard
If I make judgement on a potential collision situation that turns out to be wrong, it's rather silly to say there was a confirmed collision situation earlier. Who confirmed it? I may have simply made a misjudgement, or the wind might have increased or decreased, changing my speed, or the other vessel may have increased or decreased speed. Whether or not a collision is possible is a question of judgement, not objective fact, AIS notwithstanding.
There is nothing wrong with altering course early to prevent a collision situation developing; there's a sentence in the Colregs that advocates doing so. If I judge that I'm not in a collision situation and that turns out to be wrong, then I'll take the appropriate actions to ensure my safety. I certainly haven't impeded anyone.
 
If you are crossing a TSS under sail alone you are the stand on vessel (Rule 18(a)) unless you impede the safe passage of a vessel travelling through the TSS (Rule10(j)) or the vessel is not under command, restricted in her ability to manoeuvre or engaged in fishing (Rule 18(b)).

If you are impeding the safe passage of a vessel travelling through the TSS, then that vessel will inform you with 5 short blasts (Rule 34(d)) also maybe by other means such as light flashes.

At that point you, as the sailing boat, will become the give way vessel and it is your duty to give way (Rule16) to the vessel proceeding up the TSS.
 
ColRegs cannot possibly be relevant to anything you do not know.

If I make judgement on a potential collision situation that turns out to be wrong, it's rather silly to say there was a confirmed collision situation earlier. Who confirmed it? I may have simply made a misjudgement, or the wind might have increased or decreased, changing my speed, or the other vessel may have increased or decreased speed. Whether or not a collision is possible is a question of judgement, not objective fact, AIS notwithstanding.
There is nothing wrong with altering course early to prevent a collision situation developing; there's a sentence in the Colregs that advocates doing so. If I judge that I'm not in a collision situation and that turns out to be wrong, then I'll take the appropriate actions to ensure my safety. I certainly haven't impeded anyone.

Point missed by both I'm afraid. :)

Read again ..... boats will be in a crossing situation in an hour's time but your assessment whilst an hour out is that the crossing will be at a safe distance .... but in an hour find my judgement faulty, the Colregs apply, and I should hold my course, being the stand-on vessel.

You're not kidding that the Colregs apply.

I'm glad I'm in the Med! :encouragement:

Richard
 
Point missed by both I'm afraid. :)

Read again ..... boats will be in a crossing situation in an hour's time but your assessment whilst an hour out is that the crossing will be at a safe distance .... but in an hour find my judgement faulty, the Colregs apply, and I should hold my course, being the stand-on vessel.

You're not kidding that the Colregs apply.

I'm glad I'm in the Med! :encouragement:

Richard

OK, but I think you're overreacting. On a three-month cruise last year we had to avoid ships exactly twice, once southbound, once northbound. There was no collision situation. I had to concentrate a little harder for about an hour each time. I think I put my tea down once. No biggie, in other words.

They have ships in the med don't they?:)
 
OK, but I think you're overreacting. On a three-month cruise last year we had to avoid ships exactly twice, once southbound, once northbound. There was no collision situation. I had to concentrate a little harder for about an hour each time. I think I put my tea down once. No biggie, in other words.

They have ships in the med don't they?:)

I certainly would be reacting big-time if the first time I realised that the large vessel and I were on a collision course was after the hour had passed and the damn thing was right on top of me. :o

They do have ships in the Med but the only time I crossed and re-crossed the North Adriatic TSS there were only 2 ships anywhere near. This is my actual track on the way back from Venice to Rovinj.

Screenshot_20170112-141127.png


That all looks good to me. :)

Richard
 
I certainly would be reacting big-time if the first time I realised that the large vessel and I were on a collision course was after the hour had passed and the damn thing was right on top of me.

Richard

Ok, I get your point now. I was trying to illustrate a general principle. Obviously, I hope, constant vigilance and assessment are necessary. I don't think,"OK, I'm going to miss him, I'll have a kip for an hour!".
Your TSS track shows clearly how it is most of the time: easy!
 
Since there are so many opinions in this thread, and all with some merit, I thought I'd add mine.
The IRPCAS or Colregs are not the 'Navigating in Open Water' regulations. They only come into play in a collision situation. If I am sailing south and there's a large ship five or six miles away heading west (making me the stand-on vessel in a collision situation) and I, judging that in an hour or so, either by eye or AIS that we will be too close for comfort, alter course 45degrees to port so as to avoid a collision situation altogether, I am not infringing the Colregs. That's just prudent navigation. If I do this at the range stated, I won't yet be in a TSS. The manoeuvre if correctly judged will allow me to cross the TSS correctly, or pass behind the vessel in open water.
Should I judge that I can pass ahead, but in an hour find my judgement faulty, the Colregs apply, and I should hold my course, being the stand-on vessel. If it looks as though a collision is still likely, i.e. the other vessel does not appear to be altering course (and it's my judgement that counts here) I am obligedto avoid a collision. Perhaps the best manoeuvre here is a 90 degree turn to Starboard.
In the specific case of crossing a TSS, I aim to arrive at the edge of it at a suitable time and place so that I can cross without troubling the biggies in any way. It's really not that difficult, or that different from the 'shipping lanes'. The major difference is to make your heading 90 degrees to the direction of travel.

I think you might need to rethink your strategy.

If the ship is 6 miles away, that's EXACTLY the sort of distance that the OOW will be thinking of altering course slightly. His big radar will have plotted you and your average course and made some predications about the likely CPA (assuming he's picked you up on radar, and many times they do). Why are you doing anything? Why delay your passage and make this big alteration to port because of what 'might happen' in a while? Actually its more likely to be half an hour than and hour and if you wait fifteen or twenty minutes and take some bearings it will become obvious what's happening. In fact his likely course of action is to turn to starboard and your turn to Port will close the CPA again. Hopefully your turn is big enough, but who knows, it all depends on relative speeds was well.

If you've got AIS receiver only connected to a plotter or some sort of display it will be obvious to you.

If you've got an AIS transponder it will help the big ship see you and calculate the CPA etc.

The final bells and whistles would be an active radar transponder, but they require power...
 
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One of the earlier threads suggested the big boys filter out Class B AIS to de clutter their screens

I don't know whether that is true or not, if it is, it obviously undermines the idea that they will be watching us on their screens

Can anyone confirm this a true or not ?
 
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