Another Colregs question.

[ProDave]

This is not a who was right, who was wrong, question. Nobody was wrong. Just something that showed a gap in my knowledge.

So I am in a sail boat, but motoring, sails down, approaching a bridge. This is "at sea" not an inland waterway. Another boat was coming under the bridge. It was a wide bridge plenty of room, no navigation constraints.

Initially we are on a collision course so we have to do something. My inclination was to turn slightly to starboard, and pass the other boat port to port. That is probably influenced by too much time on the inland waterways, but that is also what I am supposed to do entering and leaving the harbour.

But before I could do that, the other boat turned to port so I did the same and we passed starboard to starboard. The change of course was done in plenty of time and was clear, no boats were in danger.

The question simply is what is the convention in this situation, are you supposed to pass port to port or starboard to starboard?

 

[awol]

Rule 14

Head-on situation.
(a) When two power-driven vessels are meeting on reciprocal or nearly reciprocal courses so as to involve risk of collision each shall alter her course to starboard so as to each shall pass on the port side of the other.

(b) Such a situation shall be deemed to exist when a vessel sees the other ahead or nearly ahead and by night she could see the masthead lights of the other in line or nearly in a line and/or both sidelights and by day she observes the corresponding aspect of the other vessel.

(c) Then a vessel is in any doubt as to whether such a situation exists she shall assume that it does exist and act accordingly.

 

[tillergirl]

Rule 9 Narrow Channels

(a) A vessel proceeding along the course of a narrow channel or fairway shall keep as near to the outer limit of the channel or fairway which lies on her starboard side as it safe and practicable.

 

[ProDave]

So my inclination was right and the other boat altered course the wrong way?

Once he had done that there was no point "arguing"

 

[capnsensible]

So my inclination was right and the other boat altered course the wrong way?

Once he had done that there was no point "arguing"

My view. You were right. Bang on . Both vessels altered. No risk of collision.

You saw it. Assessed. Job done. IMHO.

 

[DJE]

A wide bridge with plenty of room. Is it possible that the other boat saw this as a crossing situation rather than a head-on meeting?

 

[Mataji]

In the original question it is evident that there was no risk of collision so there was no need to apply col regs.

 

[ProDave]

In the original question it is evident that there was no risk of collision so there was no need to apply col regs.

We were heading directly towards each other. If neither had done anything then as we got closer there would have been that collision risk.

I thought the point of Colregs was to recognise that situation developing, and so something about it in plenty of time before it became panic stations, which is what happened.

 

[RichardS]

It's a common situation. You are heading towards another boat but are still some distance away. It looks as if you are pretty close to a head-on collision course but your feeling is that, if anything, the oncoming boat will pass closely down your starboard side.

The obvious thing to do is to increase the starboard clearance so that rather than being a few metres, it's a few dozen metres. The problem is obvious that this means turning slightly to port which a) is not the recommended manoeuvre and b) it might not be an obvious course adjustment unless you make a much bigger turn.

I've found AIS offers a perfect solution, especially if both boats are equipped with transceivers as both boats can see immediately that they will pass closely starboard to starboard, even if you're a mile or three apart, and that a slight course change immediately increases the CPA. When I've tried this turning to port tactic with another boat which is also transmitting AIS, I have seen the CPA increase when I make a slight turn to port, and then increase again when the other boat does the same.

It's a sort of secret communication in that we both know exactly what we are doing even though no words are spoken.

Without AIS, I usually wait until the boats are closer before deciding upon the best course of action.

In the OP's case, the oncoming boat possibly saw this as a stb-stb passing so increased the clearance which is actually the wrong move, as without AIS one can't be 100% sure that the other boat sees it the same.

Richard

 

[capnsensible]

One can of course and in accordance with, sound the appropriate signal of two short blasts on your sound making device to make it clear you are altering course to port.

 

[RichardS]

One can of course and in accordance with, sound the appropriate signal of two short blasts on your sound making device to make it clear you are altering course to port.

Unfortunately, I can't shout that loudly without annoying The Admiral. :ambivalence:

Richard

 

[Skylark]

In the original question it is evident that there was no risk of collision so there was no need to apply col regs.

Hard to know without being there but I tend to agree with the above. Two approaching power vessels pass port to port when a risk of collision exists. If there is plenty of room, common sense should apply, it may have been easier / convenient for the other vessel to pass down the starboard side, nothing wrong with that, it's an experience call.

 

[tillergirl]

On a couple of occasions I have had a 'head-on' situation where the other boat has been determined to starboard to starboard. I have also assumed the other party did not know the 'rules' and assumed we should drive on the left like cars!

 

[dom]

I suspect both vessels behaved properly here as port to port only applies after a collision situation has developed. For small boats this is very open for interpretation, which can annoy colreg purists - not for a moment including OP in this - who like to navigate as if driving a big ship.

If the other vessel simply fancied the side of the river on his left, he did nothing wrong in signalling as much with a clear deviation to port well in advance of colreg mandated maneuvers ....if that's what happened!

 

[ProDave]

I am sure the other vessel does know the rules, he was a small tourist trip boat, so he bloody well should. That's what made me question had I got my understanding of the rules wrong, because he should know them better than me.

 

[ProDave]

If the other vessel simply fancied the side of the river on his left, he did nothing wrong in signalling as much with a clear deviation to port well in advance of colreg mandated maneuvers ....if that's what happened!

Yes that is a fair appraisal of what happened. I too was intent on making a course alteration long before it became a "situation" but the other boat acted first with the opposite course change to what I was expecting.

Once he had turned to port and it became clear we were going to pass starboard to starboard, I did the same. As I say no point fighting it.

 

[Ohlin Karcher]

I suspect both vessels behaved properly here as port to port only applies after a collision situation has developed. For small boats this is very open for interpretation, which can annoy colreg purists - not for a moment including OP in this - who like to navigate as if driving a big ship.

If the other vessel simply fancied the side of the river on his left, he did nothing wrong in signalling as much with a clear deviation to port well in advance of colreg mandated maneuvers ....if that's what happened!

Yes and that reminds me of the Elbe No.5 Pilot Schooner collision in the Elbe River, when the syndrome you describe was the main cause of the sinking.

 

[doug748]

I suspect both vessels behaved properly here as port to port only applies after a collision situation has developed. For small boats this is very open for interpretation, which can annoy colreg purists - not for a moment including OP in this - who like to navigate as if driving a big ship.....

Yep, about sums it up. Though I always try to drive on the right where it is sensible.

 

[bbg]

I am sure the other vessel does know the rules, he was a small tourist trip boat, so he bloody well should. That's what made me question had I got my understanding of the rules wrong, because he should know them better than me.

Perhaps he wanted to turn to port anyway and was just following his normal course / route. In which case it would have made no sense for him to stand on beyond where he wanted to, just for the sake of passing port to port.

 

[john_morris_uk]

Perhaps he wanted to turn to port anyway and was just following his normal course / route. In which case it would have made no sense for him to stand on beyond where he wanted to, just for the sake of passing port to port.

Sometimes that’s what you have to do...! I know I’m stating the obvious but IRPCS take precedence over what you ‘normally or want to do.’