Colregs Puzzle

Give way, as of the other vessels current speed and heading you alter course to put yourself some distance from and heading away from the other vessel.

Not impede, take account of the restrictions and requirements of the other vessel to navigate safely and ensure that at no time do you put your vessel in a position where the stand on vessel is either unsure of your intentions or has to alter his planned course and speed.

Is that better?

Back up, turn round, head out of channel, stop where you are.... same rules as when the milk lorry comes down the lane and through the village.
No - still totally wrong :)
 
Almost as important as Rule 5: Rule 8 and in particular "Action to avoid collision ...... shall be positive, made in ample time and with regard to the observance of good seamanship." Furthermore "If necessary to avoid collision or to allow more time to assess the situation, a vessel shall slacken her speed or take all way off by stopping or reversing her means of propulsion". That usually does the trick!
 
I interpret the difference between "stand on" and "do not impede" as follows...

Where the term "stand on" is used in the regs this means maintain course and speed... i.e. in a straight line.

Where the term "do not impede" is used the they may not necessarily maintain course and speed.... they may also be necessarily following a bend in the narrow channel.... during and throughout that manoeuvre it is required that we "do not impede"

I think this illustrates the need for a separate term of "do not impede" as the requirement is different.

Just my thoughts....
 
In a narrow channel, a constrained vessel will most likely be on the port frequency

As if a ship only had a single VHF radio!

The small ship I've just got off has at least three on the bridge, generally all set to different relevant frequencies.

Pete
 
If someone impedes me I'll let them know and I'll file a full report here for analysis. This is a puzzle but only from the perspective that one piece is missing and that seems to be common sense? or am I wrong?
 
If someone impedes me I'll let them know and I'll file a full report here for analysis. This is a puzzle but only from the perspective that one piece is missing and that seems to be common sense? or am I wrong?

Of course you're not wrong. I suspect most will see how daft the questions are, apart from the handful who want a fight.
 
We encounter this problem in the Firth of Forth almost every time we put to sea. It's perfectly simple; small vessels keep out of the way of vessels navigating, of necessity, in the (in places very) narrow channel.
I think the OP has a typo in his username;-)
 
For the definitive answer.................................


Where's Daka.....:)

Now Tim has gone are you going to call on me every time you get stuck ;)

In reality the little sailing boat is never the stand on vessel .

Narrow channel = get out the way

open sea, more complex but same simple rule get out the way............


not sure if I can put this across in a way which is easily understood but will try,

A large ship has a huge horizon compared with the sailing boat , the ships captain is looking from the top of his boat, you are looking from the bottom of your sail, he sees you a long time before you see him, if the ships captain decides he is going to alter for you he will do so before you see him.

You will either see him and not pay attention to him as he has already moved for you.

If you see him and feel there is still a risk it means you have changed course /tacked unwittingly into his course as you didnt realize he was there or he hasnt seen you or he cant move for you but either way its time for you to comply with your duty to avoid a collision and keep out his way as soon as you see him.
 
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(snip)
A large ship has a huge horizon compared with the sailing boat , the ships captain is looking from the top of his boat, you are looking from the bottom of your sail, he sees you a long time before you see him, if the ships captain decides he is going to alter for you he will do so before you see him.

(snip).

How does that work then? Is his superstructure invisible? :confused:

I can see ships hull down on the horizon many miles away, but sailing boats, even with their nice shiny white sails reflecting the sun, are simply too small to see way before they drop off the edge. Motorboats are just too small to see at about half the distance cos they lack the essential safety device of a couple of large white flags.

Of course, the big ship does have electronic Magic Eyes which I don't have.
 
Now Tim has gone are you going to call on me every time you get stuck ;)

In reality the little sailing boat is never the stand on vessel .

Narrow channel = get out the way

open sea, more complex but same simple rule get out the way............


not sure if I can put this across in a way which is easily understood but will try,

A large ship has a huge horizon compared with the sailing boat , the ships captain is looking from the top of his boat, you are looking from the bottom of your sail, he sees you a long time before you see him, if the ships captain decides he is going to alter for you he will do so before you see him.

You will either see him and not pay attention to him as he has already moved for you.

If you see him and feel there is still a risk it means you have changed course /tacked unwittingly into his course as you did'nt realize he was there or he hasnt seen you or he cant move for you but either way its time for you to comply with your duty to avoid a collision and keep out his way as soon as you see him.

Although I am a great believer in keeping out of the way I would question this post. MOST ships I would expect to follow the rules IF they see the YACHT, which most will but at what range?

A huge horizon means the sails are below the horizon before he can see the yacht in all but good weather, depends how diligent the OOW is...

That means in open waters I would expect a ship to alter, if he has seen the yacht. Put a coastline, TSS, sandbank, navigational marker in the area and they might consider themselves not to be impeded :eek:

IMHO I think a diligent yacht (how many of us really look behind the genoa or behind us down wind enough?) may see the ship first but as DAKA says the ship will of decided if he is going to avoid the yacht before the yacht knows.
 
slight thread drift

'9 (b) A vessel of less than 20 meters in length or a sailing vessel shall not impede the passage of a vessel which can safely navigate only within a narrow channel or fairway.'

This rule turns a very fundamental priority (sail/pdv) on its head. However, whether a channel or fairway is 'narrow' to a craft is not an absolute, but is relative to the draft and manoeverability of a vessel, plus the skill, confidence and local knowledge of the helmsman. There's no note on the charts designatng a 'narrow channel' and no signal made by lights or shapes on a vessel to tell us when he's decided he's now stand on. No contest with a large commercial vessel, but supposing it was a large motor boat, with whom you're in relatively close quarters, who suddenly decides to stand on? Am I alone in finding that disconcerting?
 
'9 (b) A vessel of less than 20 meters in length or a sailing vessel shall not impede the passage of a vessel which can safely navigate only within a narrow channel or fairway.'

This rule turns a very fundamental priority (sail/pdv) on its head. However, whether a channel or fairway is 'narrow' to a craft is not an absolute, but is relative to the draft and manoeverability of a vessel, plus the skill, confidence and local knowledge of the helmsman. There's no note on the charts designatng a 'narrow channel' and no signal made by lights or shapes on a vessel to tell us when he's decided he's now stand on. No contest with a large commercial vessel, but supposing it was a large motor boat, with whom you're in relatively close quarters, who suddenly decides to stand on? Am I alone in finding that disconcerting?
Interesting point. In Portsmouth Harbour, the LNTM's state IIRC, that a vessel claiming to be constrained by its draft has to show the lights. Around here you are more likely to have a conflict not with the cross channel ferries, but with the smaller commercial boats that do harbour tours or go to the IoW.
Some of these commercial vessels might be a lot bigger than your yacht, but draw no more.
I sail out of Lymington from time to time, the bits outside of the channel are too shallow for a decent dinghy at LW. So the vessel that can't navigate outside the channel might be a yacht. Obviously a yacht has a lot more options in terms of manoeuvring than something that nearly fills the river, but you still have to give them somewhere to go.
 
... but supposing it was a large motor boat, with whom you're in relatively close quarters, who suddenly decides to stand on? Am I alone in finding that disconcerting?
Some years ago we were the only witnesses to a quite serious collision in the Veersemeer (Holland) between a motor yacht travelling at some speed which T-boned a sailing boat tacking up it, both of whom thought they were the stand-on vessel.

I assumed the motor yacht was in the wrong, on the "steam gives way to sail" principle. But not so said the policeman who interviewed me. The motorboat had right of way because the Veersemeer is considered to be a narrow channel (about 1/2 mile wide at that point). I should be familiar with the rules in my copy of the ANWB Water Tourism Almanac, he said. One is obliged to carry this almanac - fortunately I did - but it is written only in Dutch.
 
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I saw a similar collision puzzle to this involving a sailing vessel and a harbour ferry on collision in a narrow channel in Portland Harbour USA - the pilot of the smaller vessel, who felt bullied by the larger vessel, had drawn a sophisticated diagram and animation of his collision situation and got the views of the forum members. I'm wondering how helpful fellow skippers find it consulting the IRPCS ColRegs on their phone when analysing these sorts of problems. How helpful is the IMO IRPCS ColRegs Rules of the Road for Seagoing Sail and Power Vessels application in these kinds of situations? Does anyone have experience of the application?
 
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