Crossing Shipping Lanes

Paul it is very easy. You just head across at right angles to the shipping lane, when a ship gets near you turn parallel to it, in the direction of travel for the lane that you are in, then when it passes, turn across it's stern and continue on at right angles as before, repeat as required. You can even confirm this with the ship in question by VHF. I learned this from John Goodes videos on the matter and have used it with good effect. No body gets impeded.
 
Could someone explain what 'not impede safe passage' means in the context of crossing TSS (10j)?

To my ears it sounds like an unhelpful statement which means that the crossing small sailing boat (who has no easy way of predicting the safety or magnitude of another vessel's avoidance manoeuvres) has no idea whether he is the stand on vessel or not when crossing the TSS!
 
Could someone explain what 'not impede safe passage' means in the context of crossing TSS (10j)?

To my ears it sounds like an unhelpful statement which means that the crossing small sailing boat (who has no easy way of predicting the safety or magnitude of another vessel's avoidance manoeuvres) has no idea whether he is the stand on vessel or not when crossing the TSS!

Pretend you have never heard of the verb "impede". Then read 8f. It tells you what it means. My interpretation is that you mustn't put the other vessel in a position where it is potentially required to go somewhere that is unsafe. That would either be close to the hard stuff (or possibly into a restricted area) or directly into the path of another vessel. The former isn't usually a problem in a TSS (but likely is in a narrow channel - when the term impede also applies)).

I think it would have been much better if they had invented a new verb specifically for this purpose and then defined it in 8f. The problem is that people come with their own interpretation as to what it means to impede someone, rather than to use the explanation in 8f.
 
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Could someone explain what 'not impede safe passage' means in the context of crossing TSS (10j)?

To my ears it sounds like an unhelpful statement which means that the crossing small sailing boat (who has no easy way of predicting the safety or magnitude of another vessel's avoidance manoeuvres) has no idea whether he is the stand on vessel or not when crossing the TSS!

It should be clear by now after all the posts that rule 10 doesn't change whether a small boat is stand on or not.

These days with an AIS receiver, which is cheap to install (relative to other costs of a boat) you can have an idea of the CPA a long way out. Formerly, it required radar and the skill to use it. So you can know whether a risk of collision is going to occur and make a small tweak a long way out to avoid a situation developing where stand on is significant.

If you have neither, then the best course of action, again as posted already, is to head across at roughly 90 deg and keep a straight course and speed. Note in the MGN I posted, the MCA at least believe you should turn on the engine if you can't hold a reasonable heading and speed under sail. Ships, which usually have radar and the skill to use it, may well have altered course to avoid you several miles away. When you get closer you can use a hand-bearing compass to confirm all is ok.
 
To the OP I would say, chill. Once you have AIS onboard the stress factor crossing shipping lanes in the central English Channel reduces 80%.

  • Before departure learn how to project your AIS display forward in time so that you can visualize bearing AT TIME OF CPA. In a potential close encounter ( < 0.2 NM ) the basic CPA presented by you AIS does not help you plan to avoid the situation before it gets dicey.
  • There is no appreciable difference in behavior or density of shipping inside or 1 mile west of an English Channel shipping lane, so don't get too hung up trying to perform navigation twists & turns to avoid one.
  • Before you set off lock into your head your own definition of closest safe CPA and stick to this rational should things get tricky. I suggest 0.6NM when you are passing ahead of a ship and 0.4NM when going behind. Double these safe passing distances when outside shipping lanes.
  • Most of the time the pro mariners of the English Channel will have avoided you before they become a concern to you. However there will be times when shipping is dense that you will want to open up the CPA because a ship is constrained by other factors.
  • When you do want to open up the CPA, first try altering speed and look for a positive feedback from the AIS display, otherwise make a clear course change, (minimum 45 degrees), to go around the stern of the ship.
  • When altering course to go around the stern of a ship resume your original course asap otherwise you will confuse the next ship coming up over the horizon.
  • Ignore the numerical labeled rules quoted here, they obviously confuse the majority of small boat sailors. Read them once, understand the principals, then throw the rule book away and apply the principals. This has worked for me for 25 years.
One final thing which applies to all sailing matters, don't take advice from people who sail in other areas or a different type of vessel.

[Edit]To placate wise seadogs across the world I will amend the above statement to "when getting contradictory advice on a sailing matter, err towards following the advice of those who do the type of sailing you do".
 
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The answer is it depends. Not a lot of help ehh?

It is at first reading complicated or confusing situation,
Rules 10 applies so does rule 18. and if you put the motor on so does rule 15.

As a sailing vessel you are always the stand on vessel when risk of collision exists with a power driven vessel.

Rule 10 adds a couple of further complications. First you should cross at as near to 90 degrees as practical to the general direction of flow. Not your question so I won't get into that.

And the requirement to not impede the passage of a power driven vessel using the TSS.

What the heck does not impede mean?

Do Not Impede. Means do not get in the way in the first place.
If you do get in the way and risk of collision exists normal rules still apply and you are still a stand on vessel . If you do impede the vessel. it is still required to give way as per rule 18. Even so the requirement not to impede still exists.

It is not the same as must give way. Even so. To all intense and purpose if you are on a Sailing Vessel, a vessel of less than 20m in length or Fishing vessel engaged in fishing It's is best to treat it as if you were give way and do it early.
However once the risk of collision exists the stand on give way vessels are still the same as at any other time. Be aware. The give way vessel must give way if risk of collision exists and may alter course towards you to go around your stern.

Exactly when is a vessel is impeded ?
If it has to make a significant alteration of course or speed. Again it's not a precise definition.

Even if you have left it to this stage where risk of collision exists and you are in close quarters you are still required not to impede.

So altering course to going astern of a vessel using the TSS lane. Or against the direction of flow of traffic is not a good idea. It may alter course at the same time to go astern of you. which could be dangerous to you.
Reduce speed or alter to go with the traffic until its passed and clear, And the next one comes along.

If you are under power.

Under this circumstance rule 10 for TSS applies along with rule 15 crossing situation.

So it depends as per rule 15 you are give way to vessels crossing from your starboard side and stand on for vessels crossing from your port side.
So if you cross an entire TSS you will be give way to all the vessels transiting the TSS in one lane and stand on to all the vessels transiting the TSS in other opposite lane.
As a small vessel less than 20m in length the same shall not impede applies.

If you do impede a vessel using the TSS and risk of collision exists the normal rules still apply so you could be ether stand on or give way. The Vessel using the TSS. Should still give way.
Even so you are still required not to impede.

Again if in this situation an alteration towards a give way vessel to go astern of it would not be a good idea. Alter course away from it parallel to its course and the traffic flow until it passes. and or reduce speed.

repeat with the next one.

To summarise. Just give way early. Time your crossing to not get in the way. Treat it as if you are always give way but do not alter towards a give way vessel unless you do it early (before you enter the Lane) make it obvious. to other vessels.

Once you are in the Lane and crossing, If risk of collision exists, Alter away from the vessel using the Lane to a parallel course. or slow down or stop. Be aware the vessel using the TSS which is a give way vessel may alter to go astern of you.

Clear as Mud?

Excellent summary of the complexities and ambiguities !

However, I think you are allowed to impede (in my reading) as long as you don't impede to cause UNSAFE passage. ie you can cause the big ship to make big course alterations - that is fine (according to the rules) as long as you don't cause it to make alterations that would be UNSAFE. At least my reading of rule 10.
 
To the OP I would say, chill. Once you have AIS onboard the stress factor crossing shipping lanes in the central English Channel reduces 80%.

  • Before departure learn how to project your AIS display forward in time so that you can visualize bearing AT TIME OF CPA. In a potential close encounter ( < 0.2 NM ) the basic CPA presented by you AIS does not help you plan to avoid the situation before it gets dicey.
  • There is no appreciable difference in behavior or density of shipping inside or 1 mile west of an English Channel shipping lane, so don't get too hung up trying to perform navigation twists & turns to avoid one.
  • Before you set off lock into your head your own definition of closest safe CPA and stick to this rational should things get tricky. I suggest 0.6NM when you are passing ahead of a ship and 0.4NM when going behind. Double these safe passing distances when outside shipping lanes.
  • Most of the time the pro mariners of the English Channel will have avoided you before they become a concern to you. However there will be times when shipping is dense that you will want to open up the CPA because a ship is constrained by other factors.
  • When you do want to open up the CPA, first try altering speed and look for a positive feedback from the AIS display, otherwise make a clear course change, (minimum 45 degrees), to go around the stern of the ship.
  • When altering course to go around the stern of a ship resume your original course asap otherwise you will confuse the next ship coming up over the horizon.
  • Ignore the numerical labeled rules quoted here, they obviously confuse the majority of small boat sailors. Read them once, understand the principals, then throw the rule book away and apply the principals. This has worked for me for 25 years.
One final thing which applies to all sailing matters, don't take advice from people who sail in other areas or a different type of vessel.


Haha, probably good advice !

But my stress is not related to fear of crossing the TSS (i'm a coastal sailor) but to the existence of wording ambiguity in the Colregs TSS - perhaps pedantic, but the volume of contradictory replies on this (and other similar) thread (s) suggests they are far from simple and clear :)
 
.... One final thing which applies to all sailing matters, don't take advice from people who sail in other areas or a different type of vessel.

With the greatest of respect that would severely limit the volume of knowledge available. There is a big difference between taking advice and following advice that is not relevant. For example, I have a fairly decent understanding of heavy weather tactics, derived from various sources, much of which is from different vessels and and different sailing areas.
 
With the greatest of respect that would severely limit the volume of knowledge available. There is a big difference between taking advice and following advice that is not relevant. For example, I have a fairly decent understanding of heavy weather tactics, derived from various sources, much of which is from different vessels and and different sailing areas.
The problem facing the OP in this thread is an excess of unsuitable advice from people who do not regularly cross the English Channel, the same same applies to debates about Radar and AIS. Caribbean, Med and English Channel sailors will never agree on the usefulness of these different technologies.

When the OP is ready to venture to the Outer Hebrides I am sure he will value your advice.
 
The problem facing the OP in this thread is an excess of unsuitable advice from people who do not regularly cross the English Channel, the same same applies to debates about Radar and AIS. Caribbean, Med and English Channel sailors will never agree on the usefulness of these different technologies.

When the OP is ready to venture to the Outer Hebrides I am sure he will value your advice.

Please, don't be so pompous. You assume the OP or anyone else is incapable of filtering information. You have made a pathetic claim and are trying to pass it off as great wisdom.
 
[*]When you do want to open up the CPA, first try altering speed and look for a positive feedback from the AIS display, otherwise make a clear course change, (minimum 45 degrees), to go around the stern of the ship.
[*]
.

Ohhhh yes, that should do it!

You're right, I was getting all confused earlier.

If anything looks a little close try speeding up and slowing down again. Repeat as necessary until he has no idea what your're up to. You need to do this until he gets about a mile off.

Then and when he only has the room to make one more course adjustment turn 45 degrees towards him. It needs to be about 45 degrees otherwise you will stand no chance of hitting him head on. By now he would have initiated a last gasp turn to pass behind you too.

As soon as he starts to sound the ships whistle get up on the fore deck as quick as you can and start with giving him the finger. If you have a loud hailer even better, you can shout insults at him. Just before he hits you try shouting "starboard", "water" or "rule 41". Any of these will buy you a few more moments of confusion.

In the unlikely event he does miss you don't worry.

There will be another one along in about ten minutes...


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Please, don't be so pompous. You assume the OP or anyone else is incapable of filtering information. You have made a pathetic claim and are trying to pass it off as great wisdom.
The pomposity in this thread so far has been from those contributors who have engaged in trading faulty claims and counter claims about who is the best armchair amateur sea lawyer. The fact that they cannot agree indicates few have a solid understanding of collision rules and fewer still are providing help to the OP.

The OP has told us he wants help for his first Channel crossing, this indicates he might well struggle to filter out the unsuitable advice in this thread.
 
I don't disagree on that point but your claim was made for all advise. It is the nature of such forums as this one to be exactly like you say, but it is also self regulated to an extent. This therefore demands that one has to be able to review posts in a critical way, question further if required and come to a conclusion.
 
Could someone explain what 'not impede safe passage' means in the context of crossing TSS (10j)?

To my ears it sounds like an unhelpful statement which means that the crossing small sailing boat (who has no easy way of predicting the safety or magnitude of another vessel's avoidance manoeuvres) has no idea whether he is the stand on vessel or not when crossing the TSS!
The meaning of "not to impede" is clearly defined in rule 8 (f) (I) as saying you must take early action to allow sufficient sea room to allow the other vessel to manoeuvre safely.

It seems to me that that is clear - provided the vessel can manoeuvre safely you are not impeding him. However others would suggest that making the other vessel change course at all is impeding. I find that unlikely because if that were the intent the wording would be clearer, or they would have made the crossing vessel give way and avoided any doubt.

But AFAIK this wording has not been tested in court and so no one can give a definitive definition.
 
Ohhhh yes, that should do it!

You're right, I was getting all confused earlier.

If anything looks a little close try speeding up and slowing down again. Repeat as necessary until he has no idea what your're up to. You need to do this until he gets about a mile off.
In a typical YBW slanging match I would ignore such a nonsense post but since the OP has made a genuine request for help I suppose I am obliged to pick apart your dangerous opinion.

I did not and would not recommend multiple changes in speed for the reason you speculate about. Had the OP followed my initial advice and gained familiarity with his AIS display in order to forecast bearing at time of CPA he would then know whether speeding up for slowing down is required. One change of speed is enough.

I have lost count of the number of times I have read posts on this forum recommending such action, are they all wrong? Pre AIS I used to be in the big course change camp but these days I get through a TSS or shipping lane faster with an occasional contribution from some engine RPM.

You need to do this until he gets about a mile off. Then and when he only has the room to make one more course adjustment turn 45 degrees towards him
The wise AIS assisted small boat navigator should be able to act in a close crossing situation at 2 to 3 miles minimum.

I am struggling to understand why you consider a 45 degree turn to navigate around a ships stern at 2 miles a dangerous "turn towards him".
It needs to be about 45 degrees otherwise you will stand no chance of hitting him head on. By now he would have initiated a last gasp turn to pass behind you too.
Do you recommend smaller subtle course changes when a slow moving yacht decides to take avoiding action when crossing a large vessel moving 3 times faster. All advice I have read on this subject emphasizes making clear unambiguous changes. In my experience 45 degrees is about right as it represents a clear intention, anything more could lead to a ponderous zigzag course across the shipping lane.

In the unlikely event he does miss you don't worry.

There will be another one along in about ten minutes...
In your clumsy condescending humour you do accidentally highlight the real challenge crossing a channel shipping lane. Avoiding a single ship is easy, avoiding a pack of 3 or 4 leads to some mental chess-play trigonometry.
 
I am struggling to understand why you consider a 45 degree turn to navigate around a ships stern at 2 miles a dangerous "turn towards him".

Do you recommend smaller subtle course changes when a slow moving yacht decides to take avoiding action when crossing a large vessel moving 3 times faster. .

OK, being serious for a moment.

1) If you do need to make a turn to avoid a collision it should be in the direction the ship is heading. Not towards it.

2) I'm not advocating a subtle course change at all. I'm advocating maintaining a steady course and speed.

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OK, being serious for a moment.

1) If you do need to make a turn to avoid a collision it should be in the direction the ship is heading. Not towards it.
This is contrary to the oft quoted "steer for the stern" rule of thumb.

Given a 90 degree crossing, a CPA of 0.2 crossing ahead of a ship which is two miles away, then to apply your advice a yacht could need to turn a near full 90 degrees and for longer before resuming a course to pass astern. The net result of this policy is a small vessel spending longer in the shipping lane or TSS.

2) I'm not advocating a subtle course change at all. I'm advocating maintaining a steady course and speed.
Don't we all, but when the AIS shows 0.2NM crossing ahead of a ship, how long do you hold your course and when you do decide to bail out of the eyeball to eyeball confrontation with a ship what action do you take?
 
I don't disagree on that point but your claim was made for all advise. It is the nature of such forums as this one to be exactly like you say, but it is also self regulated to an extent. This therefore demands that one has to be able to review posts in a critical way, question further if required and come to a conclusion.
I have amended the original post that irked you.
 
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