Colregs question - arose today.

[BlueSkyNick]

Motoring at 6.8 knots in open water with poor viz, ie 1 mile. Spot a target about 3 miles ahead on the radar. Realise from closing speeds that he is coming towards as at similar speed. At 1.5 miles, decide he is going to pass us starboard to starboard, at about 0.3 of a mile. Out of the gloom comes a fishing boat circa 80ft. No lights or day signals.

Pass with no problem. However, debate in the cockpit starts. He is on our starboard bow, and we are on his starboard bow.

If one turns to starboard, to pass port to port and the other doesnt, a possible collision could occur.

Who should take any action, if any?

 

[Rustyknight]

If you thought he was going to 1/3 of a mile away when you passed, then doing nothing was the right action IMHO (on the proviso that you kept a close eye on him.)

Sometimes blindly following the Colregs takes second place to common sense.....

 

[BlueSkyNick]

ah shucks Rusty, don't spoil a Colreg argument by bringing commonsense into the equation - well not so soon, anyway!

Yes, we did nothing though - it was just a debate after the event which ensued.

 

[l'escargot]

If one decides to alter course when they are passing safely and puts themselves on a collision course, then they should avoid the collision by turning back again if the other vessel doesn't reciprocate.

 

[Rustyknight]

No doubt, as usually happens, people will only read the first post and jump in with both feet.......

/forums/images/graemlins/laugh.gif

 

[peterb]

[ QUOTE ]
Motoring at 6.8 knots in open water with poor viz, ie 1 mile. Spot a target about 3 miles ahead on the radar. Realise from closing speeds that he is coming towards as at similar speed. At 1.5 miles, decide he is going to pass us starboard to starboard, at about 0.3 of a mile. Out of the gloom comes a fishing boat circa 80ft. No lights or day signals.

[/ QUOTE ]

Rule 19(d): A vessel which detects by radar alone the presence of another vessel shall determine if a close-quarters situation is developing and/or risk of collision exists. If so, she shall take avoiding action .........


You did so detect another vessel, but determined that there was no risk of collision provided that the other vessel maintained its course. Correctly, you maintained your course, and there was no collision. What's more to say?

 

[kengill]

Pat Pat

 

[Sixpence]

Are you saying that if circumstances were different and a collision WAS likely , if so , as you have detected the other vessel and you don't know if he has detected you then it falls on you to take definate action and make a course correction or basically turn sharply to starboard to pass port to port , then if he has also seen you he should take the same action but in the end you both turn the same way which results in a clear port to port pass , or have I missed something here ? I'm probably totally wrong but at least an attempt to understand the question /forums/images/graemlins/blush.gif

 

[peterb]

Rule 19 says that in the event of a vessel forward of the beam being detected by radar on a collision course, then one should not turn to port. Apparently one can speed up, slow down, stop or turn to starboard; just not turn to port. But if you consider the head-on collision case, no change of speed will avoid the collision; all it will do is accelerate or delay the fateful crunch. To avoid the collision you must alter course, and 19(d) says that the alteration must be to starboard. If the other vessel has radar, then she should do the same.

Interestingly, we had a similar experience in fog south of Guernsey last Monday. Two vessels roughly abeam of each other on courses reciprocal to ours, one dead ahead and the other about 400 yds to starboard. We altered course to starboard to remove the danger from the one ahead, then went to port to slide between them. Don't know whether they saw us or not; our only 'siting' was by radar. Judging by their speed, about 4 kn, they were both small craft.

 

[Sixpence]

Still learning and I learn slow so although some might laugh at the discussions , others benefit from keeping it serious , so thanks for your reply , but in essence , I am correct ? I hope

 

[Cruiser2B]

Just to be clear, the Rule 14 - head on rule doesn't apply in restricted vis. So that only leaves the Rule 19 thou shalt not turn to port for a vessel ahead, which leaves, as so many have wisely stated - slowing, stopping or turning to stbd. In any event, but particularly in restricted vis, you should make your avoiding manoeuvres large enough to: (a) be visible by the other vsl's radar; and (b) be effective in avoiding the other vessel by your manoeuvre alone. It is not a good idea to manoeuvre half-way and assume the other guy will make up the difference. Standing on and closely monitoring the situation as you did was a perfectly acceptable course of action.

 

[l'escargot]

[ QUOTE ]
Just to be clear, the Rule 14 - head on rule doesn't apply in restricted vis....

[/ QUOTE ]
Where does it say that then?

 

[gandy]

It doesn't in so many words. But rule 14 is within Part II, which is headed "Section II. Conduct of vessels in sight of one another".

I don't know where you stand if its restricted visibility, but you are still able to see the other vessel. Or maybe worse, if one vessel can see, the other can't.

 

[Richard10002]

[ QUOTE ]
Spot a target about 3 miles ahead on the radar. Realise from closing speeds that he is coming towards as at similar speed. At 1.5 miles, decide he is going to pass us starboard to starboard, at about 0.3 of a mile.

[/ QUOTE ]

Nick,

if he is doing 7 knots on a parallel course he will cover the 1.5 miles in 13 minutes.

If you turned 90 degrees to starboard you would cover 1.5 miles in the same time, thus making the passing distance 1.2 miles. He would almost have to chase you to hit you if you took this action.

If you stop, or slow to steerage way speed, you will see each other at 1 mile or so, and have more time to take action.... 10 minutes for him to cover the mile if you are almost stopped. . You would actually see a good port aspect when you see him if you took this action but, if necessary, you can put yourself a mile away from where you are in those 10 minutes at 6 knots.

So you have to make a decision, (fairly quickly), as to whether there is a risk of collision with a 0.3 mile passing distance. That bit is a judgement call. Then you live or die by your decision, (hopefully metaphorically speaking). If you think that the time available is not long enough for you to compute and make a decision, you are probably going too fast. I read your post last night, and have had a few hours sleep before coming up with this /forums/images/graemlins/laugh.gif

I dont know what I would do in the same circumstances, but one thing that I have learned over the years is that stop/slow down is a very effective action, as is a 90 degree or 180 degree alteration of course.

just my 2 penn'orth

You seem to be making good progress.

Richard

 

[tcm]

you callem and say port-port, ok?

 

[Cruiser2B]

[ QUOTE ]
I don't know where you stand if its restricted visibility, but you are still able to see the other vessel. Or maybe worse, if one vessel can see, the other can't.

[/ QUOTE ]

As soon as you can see the other vessel, the section II rules take effect. Rule 3(k) "Vessels shall be deemed to be in sight of one another only when one can be observed visually from the other." In the rare occurrence where one is visible and the other isn't, then you'll have one vessel following the section II rules and the other Section III, but their actions should for the most part be compatible.