Crossing Shipping Lanes (again)
- Thread starter Yealm
- Start date
Yealm
Well-Known Member
In my ignorance, I wasn’t aware of the not turning to port thing.
Where in Colregs does it come from ?
Where in Colregs does it come from ?
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VicS
Well-Known Member
As far as I am aware the only place this is mentioned is rule 19 (d) (i) which applies to a vessel forward of the beam, in restricted visibility, detected by radar alone
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/281965/msn1781.pdf
john_morris_uk
Well-Known Member
Sticking with power driven vessels and without any other factors:
If we take the case of vessels approaching each other head on, the rules specifically say 'make an alteration of course to starboard'.
In crossing situations we have two scenarios.
The first is we detect a vessel on our starboard side approaching and we assess that there is a risk of collision. We are the give way vessel. The quickest and easiest way to avoid him is to turn to Starboard and pass behind him. The rules specifically say, 'avoid passing close ahead of him' so altering to Port to try and get a bit more ground to pass ahead seems to be out of the question. Altering course to Port and slowing down to allow him to overtake us is also slow and for a big ship it's a waste of fuel.
The second scenario is we see a vessel on our port side approaching and we assess there is a risk of collision. The rules REQUIRE us to stand on and monitor and only alter course when it becomes obvious that the other vessel is not taking avoiding action. A turn to Port would be potentially very dangerous as if the other vessel decided to wake up and alter course - he's almost certainly going to alter to starboard and we're in a head on situation. If we alter to starboard, we increase the time to potential collision and allow him to pass ahead of us safely. (While we wave a friendly fist at him for not applying IRPCS)
Overtaking, the overtaking vessel keeps clear until past and clear. Doesn't matter which side you go.
None of this is actually very hard in practice so long as you don't get in a spin at the first sight of a ship on the horizon. They aren't trying to run you down and if you apply the IRPCS, they will also (invariably) apply the IRPCS and everyone is happy.
Yealm
Well-Known Member
Mmm. I wonder why they didn’t write Rule 15 to include the turning to starboard bit, if that’s what everyone is doing ..Not sure if it’s at all obvious to a newbie sailor studying the rules.
john_morris_uk
Well-Known Member
Because as others have pointed out, it isn't a cast iron rule but makes sense as normal practice until circumstances dictate otherwise.
The overreaching rule is to prevent collision and everyone has a duty to do that. Although all the guides and all the seamanship training will suggest that you usually alter to starboard in lots of situations, real life isn't always like that and there might be a ship in the way or any other hazard that means you can't turn to starboard and have to turn to port.
Yealm
Well-Known Member
I don’t think that matters if it’s not a cast iron rule.
If as people have stated, it’s common practice and to do otherwise would possibly confuse and increase risk of collisions, then surely rule 15 should include something like ‘turning to starboard should be the first choice manoeuvre if you are the give way vessel’ ?
If
If as people have stated, it’s common practice and to do otherwise would possibly confuse and increase risk of collisions, then surely rule 15 should include something like ‘turning to starboard should be the first choice manoeuvre if you are the give way vessel’ ?
If
john_morris_uk
Well-Known Member
I'll let you lobby the IMO on that one.
lw395
Well-Known Member
No.
There are many times when it would be a poor choice.
For instance if the give way vessel is big and fast compared to the stand-on, and assesses that it will pass too close ahead of the stand-on, it makes sense to turn to port.
Also don't forget that a ship in the lanes south of wight will probably be watching several other ships going in the same direction, and will have obligations to many of them. So his alteration to accomodate a crossing vessel is often restricted.
East Cardinal
Well-Known Member
Rule 15 deals with the crossing situation.
“When two power-driven vessels are crossing so as to involve risk of collision, the vessel which has the other on her own starboard side shall keep out of the way and shall, if the circumstances of the case admit, avoid crossing ahead of the other vessel.”
The rule is stating which vessel should give way in the crosssing situation. It allows the captain to decide how that can best be achieved. It warns against manoeuvres that would cause the give way vessel to pass ahead of the stand on vessel.
If you think of the situation where you have a ship on your stbd side and are give way vessel, a turn to port would be most likely to cause you to cross ahead. A turn to starboard or speed reduction would allow you to pass astern. There may be circumstances where a turn to port and increase in speed would be only option. For example if you had rocks on stbd side and another vessel close astern of you.
The rules allow for this.
The thing to be careful of is doing something unexpected by the other vessel. If everyone is following same rule then things are somewhat clearer.
john_morris_uk
Well-Known Member
First answer doesn't make sense - or at least it makes as much or more sense to turn to starboard.
Second, although what you say is true, I don't think it's the problem you are making it out to be. If the ship is obliged to keep clear of you, they invariably do. The OOW's are quite capable of watching a few targets and avoiding running down a small vessel is just as important to their career as colliding with another big ship.
SimonFa
Well-Known Member
Am I missing something here?
You say a vessel is on collision course coming from starboard but I can’t turn to starboard because of rocks, so I can turn to port? Presumably he’s amongst those rocks and in a RAM situation so those rules apply?
I think this scenario is highly unlikely for the situation of crossing shipping lanes.
Dukester52
Well-Known Member
Correct me if I'm wrong, but I don't believe the OP was suggesting a turn to port to pass in FRONT of the stand-on vessel? Rather to avoid and to move 'in parallel', or to port of, the other vessel until it had passed. If this was in a TSS (although this wasn't the OP's point) he'd then be following the direction of traffic, rather than going in the opposite direction, which would also be likely to cause confusion? Without double checking the colregs, I can see some merit in a turn to port in this situation. [ducks]
RobbieW
Well-Known Member
I'll give you an example;
Crossing Biscay last year and running in roughly NE toward Benodet about 80 miles off, motor sailing. AIS showed two ships at roughly 90 to my track, presumably going to/from Bilbao/Santander, one a smallish bulk carrier the other a cruise ship / ferry. I'm clearly give way to the bulk carrier and stand on the ferry. AIS shows that we'll all meet within about a mile circle, in particular the ferry is consistently showing a CPA of 0 to 500 metres crossing ahead at 5 miles out. Ferry cant go to port as he conflicts with the bulk and shows no sign of making a turn to starboard in about 30 mins of monitoring which he needed to do to give me the security of a clear and unambiguous turn to indicate intention to pass astern.
To my mind the ferry was not following IRPCS as he was not making his intentions clear within my comfort zone - I appreciate thats my comfort zone. In general OpenCPN is pretty good at plotting CPAs and crossing points, especially as I have both my track and target tracks set up to show 30 mins of travel - in short I've learned to trust it. I dont transmit AIS but do have a radar transponder which was on. This sort of situation is more typical in my experience than the turns others report. I wont tell what I did because not really relevant to my point but you can probably guess
Edit: Actually, because its relevant, what I did was make a 60-70 turn to port until I was clear to go behind both ferry and bulk. That, IMO, was clear and unambiguous to the ferry about my intention. The ferry didnt alter
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Uricanejack
Well-Known Member
To quote an old friend "rules provide guidance for the wise and adhered to by fool's" he wasn't limiting the comment to colregs. I doubt it was an original thought, although he was someone I considered wise.
The rules provide guidance to help seamen make sense out of thousands of possible situations. The rules are written about 2 vessels yet often there are many more than 2 vessels. The rules leave some wiggle room by not being to prescriptive to allow seamen to interoperate the rules and have some flexibility to apply the ordinary practice of seamen. Which is just another way of saying common sense and experience.
The scenario you posed is a good one. It is a legitimate example where the usual 2 ship simple answer may not be the best. The rules allow you as skipper or master of your vessel to choose what you think is the best solution to your situation.
To make the requirement to perceptive. Might in rare circumstance have required a vessel to take an less safe action than the best action.
The general advice to avoid an alteration to port. Is usually good practice and first choice. But not always.
When I am give way. I give way.
My first choice is usually an alteration to starboard.
My second a reduction in speed.
I could combine the two choices.
Alterations of course are much more readily apparent to the observer(watch Keeper) on another vessel if they are "bold" bold is never quantified in the actual rules or even stated the rules use the term "readily apparent"
Court cases and recommended practice describe "bold" or "Readily Apparent" as an alteration of 60 or more degrees. This is to make it apparent on a RADAR screen.
Visually a change of aspect or direction can be spotted much more easily than a change of speed. By changing course you are indicating to the other vessel you have seen them and taken action.
Reducing speed to stopped or minimum steerage is also quite apparent.
Combining a reduction of speed with an alteration to port to parallel a ship transiting a traffic lane or narrow channel when you are the give way vessel. Will be apparent to the OOW on the ship. An experienced OOW will not be confused.
Is it the best strategy? Maybe, Maybe Not. Is it permissible? Yes.
One area I differ in opinion from quite a few people here. I advocate "do not impede" it is in the rules. Even as a stand on vessel. If I am a small sailing vessel or under power. I will choose "not to impede" By turning away from the vessel I do not want to "impede" to a parallel course and reducing speed.. I almost always get an appreciative wave with all 5 fingers from the OOW and quite often a thank you over the VHF. Even though I didn't call.
I often sail in quite busy narrow channels and occasionally in adopted TSS. What works in my circumstance may not be the best in others. The density of traffic and available sea room makes a significant difference. The rules have flexibility to allow you as skipper to asses the situation based on all the factors and provide guidance for you to make your decision on the best action.
There is a very simple truism. The first rule "don't have a collision". It's not the first rule its actually the second. No mater what the rules say.Do what you have to avoid a collision. How to apply. Is a thread all by itself
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capnsensible
Well-Known Member
Thanks Uricanejack for all your thoughtful posts on the collision regulations. I always enjoy them, find them stimulating and endeavour to put into practice your wise words. And pass them on to others.
Yealm
Well-Known Member
Yes exactly this.
If you are trying to cross a procession of ships it may make more sense (from your own selfish passage plan viewpoint) to turn to port (and crosss after the ship has passed) than to turn to starboard.
But other posters have suggested this is not allowed or is not the ‘done thing’ and might be confusing to the other party. I can see nothing written in Colregs to support this.
Are there guidence notes to Colregs that discuss these scenarios in more detail ? Or any other source that discusses the asymmetric encounters between vessels that differ markedly in speed and manoeuvrability?
Edit...
To answer my own questiion - I think Rule 17 says you shouldn’t go to port !
If you are trying to cross a procession of ships it may make more sense (from your own selfish passage plan viewpoint) to turn to port (and crosss after the ship has passed) than to turn to starboard.
But other posters have suggested this is not allowed or is not the ‘done thing’ and might be confusing to the other party. I can see nothing written in Colregs to support this.
Are there guidence notes to Colregs that discuss these scenarios in more detail ? Or any other source that discusses the asymmetric encounters between vessels that differ markedly in speed and manoeuvrability?
Edit...
To answer my own questiion - I think Rule 17 says you shouldn’t go to port !
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{151760}
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Rule 17c, in relation to (a)(ii).
Uricanejack
Well-Known Member
"RULE 17 Action by Stand-on Vessel"
Just to try and clarify an important point RULE 17 Action by Stand-on Vessel. as the title implies does not restrict the options available to the give way vessel. It imposes certain burdens or requirements on only the stand on vessel.
Rule 17 is worthy of an entire thread or even a book certainly lots of case law exists.
JM already gave a very simple explanation of why rule 17 imposes a restriction on the stand on vessel altering to port.
The give way vessel may still take action as is required . This action will very likely be an alteration to starboard.
An alteration to Port by a stand on vessel may appear to be a simple resolve but could in practice be very dangerous.
A small point to remember. "Not all stand on vessels have the give way vessel on their port side". When "sailing" the power driven give way vessel may be on your starboard side.
In Practice rule 17 advises don't alter towards a give way vessel. This would be a situation where an alteration to port would be safer.
Just to try and clarify an important point RULE 17 Action by Stand-on Vessel. as the title implies does not restrict the options available to the give way vessel. It imposes certain burdens or requirements on only the stand on vessel.
Rule 17 is worthy of an entire thread or even a book certainly lots of case law exists.
JM already gave a very simple explanation of why rule 17 imposes a restriction on the stand on vessel altering to port.
The give way vessel may still take action as is required . This action will very likely be an alteration to starboard.
An alteration to Port by a stand on vessel may appear to be a simple resolve but could in practice be very dangerous.
A small point to remember. "Not all stand on vessels have the give way vessel on their port side". When "sailing" the power driven give way vessel may be on your starboard side.
In Practice rule 17 advises don't alter towards a give way vessel. This would be a situation where an alteration to port would be safer.
Uricanejack
Well-Known Member
Thanks