Crossing Shipping Lanes

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 ?

Its possible but the facility if supposed to be used in confined waters where there alarms would be sounding continuously with the number of Class B's about. There's no evidence to suggest they have them switched off in open waters. In fact they'd be foolish to as its an aid to them as well.

If its of any consequence I turn our AIS off in confined waters. Otherwise as I steam up the Tamar it keeps telling me I'm about to come close to some ship that's anchored or moored...
 
Can anyone confirm this a true or not ?
Anyone who offers a strong binary opinion on this question is likely to be a bluffer and best ignored.

This rumour has been debated here for years, the consensus is, yes it is possible but what is the motivation to do so in open water where it really matters to a small boat sailor.
 
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...

I was trying to make general point rather than a detailed passage plan.
Altering course early to avoid a collision situation developing is good seamanship, and is advocated in rule 8. Constant vigilance is always necessary.
 
I was trying to make general point rather than a detailed passage plan.
Altering course early to avoid a collision situation developing is good seamanship, and is advocated in rule 8. Constant vigilance is always necessary.
I remain rather unconvinced of your description of 'early' for the ship, 12 miles might be early, but he's probably barely visible to you at 12 miles. At 6 miles, it's too late and he's already altering. Just watch and monitor and things fall into place nearly all the time. All IMHO.
 
Hmmm. At 20 knots, that 18 minutes.
Doesn't accord with my experience....

Ok Mr Picky, "probably already altering". At 18 knots it might be at greater range as those 18 minutes go very quickly. Try it at 30 knots. (Except I freely admit that I wasn't allowed to do 30 knots in crowded waters, so I only know it from being OOW2). I understand the closing speed of aircraft is a bit faster?
 
I am almost giving up trying to explain what rule 10 J actually means.
So many of you believe its irrelevant. However I still have some hope some of the newer sailors who were asking still have open minds.

The idea seams to be firmly implanted in your heads that ships will avoid you by taking avoiding action a long range by making a minor course adjustment so rule 10 J requirement not to impede does not matter.
Some, possibly even most might do this some or even most of the time. If so fine and dandy everyone is happy.

Are you guys who claim they will all do this Physic?
Some possible even quite a few may not. Particularly when dealing with small sail boats and fishing vessels. Both are well known to make frequent changes of course. Often particularly summer and long weekends, there's loads of them all over the place.
A lot of the small alterations made by ships in a TSS particularly when there is a group proceeding at similar speeds. Is to avoid converging slowly with another. And keeping a minimum safe distance from each other. So they can maneuver.

In some circumstance a frequently employed tactic is to make sure you have a bit of sea room. Wait and see what the small boats do. Hoping most will not impede. Dealing with what's left over.

You do not know what the OOW of a ship is planning. 6 or 12 miles away. You are guessing. and hoping you are his biggest concern or highest priority.

I have also seen comments, About having reported rouge ships for having no one on the Bridge. Or because once passed close by one of you and you couldn't see anyone on the Bridge. I find it hard to believe any ship in or anywhere near the English Channel has no one on the Bridge. They might not have as many as they should. They might be fatigued, They may or may not be well trained. They are all different. With Different attitudes and experience.

I regularly pass ships, tugs ferries, where I cant see anyone on the Bridge. Why? Because I am in a little bitty sailboat about 6 ft from sea level. (I am about 6ft tall) and the Bridge is 30, 40 even 60 ft up in the air. All I can see in the bridge window is the deck head, So unless the OOW is standing right by the window of course I wont see him or her. They are probably back I the middle somewhere looking at a RADAR.
Some times (particularly when I don't impede them) I do see the OOW or the Look out who comes over to the window and gives me a friendly wave. With all 5 fingers.

I often in open water rely on the rules and fully expect if I stand on as required at ship will act accordingly and give way. They almost always do.

In the a narrow Channel or when crossing a TSS I maintain as steady a course and speed as I can. I keep a look out. In decent Vis I can see them miles away. I can tell if they will come close. If they appear to be coming close, I stay out the way.
If there is a group of them its just easier to avoid the group.

And I particularly do not pass ahead of them with small CPAs

Personally when at leisure, I think a gentleman will give a working man a break:)
 
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Ok Mr Picky, "probably already altering". At 18 knots it might be at greater range as those 18 minutes go very quickly. Try it at 30 knots. (Except I freely admit that I wasn't allowed to do 30 knots in crowded waters, so I only know it from being OOW2). I understand the closing speed of aircraft is a bit faster?

Surprisingly its sometimes easier when you are going faster. Nobody will over take you. You can adjust your speed. Good luck trying to explain this to an enquiry.
 
I am almost giving up trying to explain what rule 10 J actually means.
So many of you believe its irrelevant. However I still have some hope some of the newer sailors who were asking still have open minds.

The idea seams to be firmly implanted in your heads that ships will avoid you by taking avoiding action a long range by making a minor course adjustment so rule 10 J requirement not to impede does not matter.
Some, possibly even most might do this some or even most of the time. If so fine and dandy everyone is happy.

Are you guys who claim they will all do this Physic?
Some possible even quite a few may not. Particularly when dealing with small sail boats and fishing vessels. Both are well known to make frequent changes of course. Often particularly summer and long weekends, there's loads of them all over the place.
A lot of the small alterations made by ships in a TSS particularly when there is a group proceeding at similar speeds. Is to avoid converging slowly with another. And keeping a minimum safe distance from each other. So they can maneuver.

In some circumstance a frequently employed tactic is to make sure you have a bit of sea room. Wait and see what the small boats do. Hoping most will not impede. Dealing with what's left over.

You do not know what the OOW of a ship is planning. 6 or 12 miles away. You are guessing. and hoping you are his biggest concern or highest priority.

I have also seen comments, About having reported rouge ships for having no one on the Bridge. Or because once passed close by one of you and you couldn't see anyone on the Bridge. I find it hard to believe any ship in or anywhere near the English Channel has no one on the Bridge. They might not have as many as they should. They might be fatigued, They may or may not be well trained. They are all different. With Different attitudes and experience.

I regularly pass ships, tugs ferries, where I cant see anyone on the Bridge. Why? Because I am in a little bitty sailboat about 6 ft from sea level. (I am about 6ft tall) and the Bridge is 30, 40 even 60 ft up in the air. All I can see in the bridge window is the deck head, So unless the OOW is standing right by the window of course I wont see him or her. They are probably back I the middle somewhere looking at a RADAR.
Some times (particularly when I don't impede them) I do see the OOW or the Look out who comes over to the window and gives me a friendly wave. With all 5 fingers.

I often in open water rely on the rules and fully expect if I stand on as required at ship will act accordingly and give way. They almost always do.

In the a narrow Channel or when crossing a TSS I maintain as steady a course and speed as I can. I keep a look out. In decent Vis I can see them miles away. I can tell if they will come close. If they appear to be coming close, I stay out the way.
If there is a group of them its just easier to avoid the group.

And I particularly do not pass ahead of them with small CPAs

Personally when at leisure, I think a gentleman will give a working man a break:)

I was with you all the way until the last sentence. My previous post wasn't necessarily referring to TSS and was when there was only one other ship and me.

However if we are crossing a TSS I completely agree that one can't guess what's going on in the mind of the OOW of another ship, but there again at 6 miles or more, without AIS or a very decent radar, a small boat has no idea how close that ship is going to get to it. Hence my 'wait and see'. If it really starts to look as though you are going to force the ship to make large alterations and 'impede' it then is the time to do something about it but I'm still not convinced about large alterations to port though. Maintaining heading and slowing right down to let it pass ahead might be an option?

Surprisingly its sometimes easier when you are going faster. Nobody will over take you. You can adjust your speed. Good luck trying to explain this to an enquiry.
. As I've never got into a situation where I was overly worried about actually getting anywhere near an actual collision, hopefully any Inquiry in the Court of Inquiry sense is never going to happen. Whilst I've watch kept and spent many hours on the bridge of ships (merchant and military) the vessels I sail now are yachts or power yachts. A few of the power boats will do 30 plus knots but only when I'm not paying the fuel bill!
 
I was with you all the way until the last sentence. My previous post wasn't necessarily referring to TSS and was when there was only one other ship and me.

However if we are crossing a TSS I completely agree that one can't guess what's going on in the mind of the OOW of another ship, but there again at 6 miles or more, without AIS or a very decent radar, a small boat has no idea how close that ship is going to get to it. Hence my 'wait and see'. If it really starts to look as though you are going to force the ship to make large alterations and 'impede' it then is the time to do something about it but I'm still not convinced about large alterations to port though. Maintaining heading and slowing right down to let it pass ahead might be an option?

!

The last sentence is just a silly comment along with the speed remark.

I don't disagree with wait and see. When its far away. I would generally wait and see. Apart from anything else. There may be other considerations for both of us.
I tend to disagree. With the large alteration being the basis of impede. My interpretation, Its the risk of collision which defines the impediment.
Even in a quite traffic area. Like some of the ones I routinely transit. It may be only one ship and me in one sail boat. Is the ship impeded.?
Some might say no.
If he makes a minor adjustment at long range. No issue, the situation never develops. Everyone is happy. I agree so long as it's at long range. The time I am talking about is when long range is over.

I wait and see. I determine the ship is on a steady bearing.
One of us has to do something.

In open water I would Stand on and wait for him to act. I would expect an alteration large enough for it to be readily apparent to me.
If I did not see an alteration large enough to be readily apparent. I would now be in doubt the ship was going to act as required in sufficient time and take action.

Replace the open water with TSS. I have two choices. One is not to impede as required.
The other is to stand on. and wait for the ship to act.

I am back to waiting for an alteration large enough to be readily apparent to me.
If I stand on I am putting a burden on the vessel using the TSS to take action as a give way vessel. If the OOW on the vessel only makes a minor adjustment. He is not acting as a give way vessel should as required by the rules. The ships action at this point should be readily apparent to me.

What is readily apparent? Bold is generally accepted as 60 or more. I am not expecting bold just obvious visually.
I would suggest good practice. For an alteration to be readily apparent. Is to show the other side light.
In order for me to be comfortable with a vessels actions I would be expecting an alteration sufficient to see the other side of her bow as the ship alters to go astern of me. If I am sailing this alteration would possibly be only a point or two maybe a bit more if I was sailing quite fast and the ship was quite slow.

Even in a TSS if there are only the two of us. It might not be an unreasonable argument to say. There was no reason why the ship could not easily make an alteration as just described. So no impediment
TSS are usually located in areas where having only the two of us is unlikely. There is usually other vessels some small some big. The other big vessels and the other small vessels are the hazard.
This is roughly the time I would choose to take action to not impede. This should clearly be large enough to be readily apparent. A large change of speed or course? Take your pick what works better.
As with any other alteration for a give way vessel alter away from it JIK. which should also be with the flow of traffic.
Even with all said each situation is unique.
 
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