Originally Posted by davefromoregon
I have a pretty academic question. Imagine a narrow channel. Two ships on opposite direction courses. The both ships draw approximately the same amount and are constrained by depth. Neither is fishing. Neither is towing. It is not clear that the two vessels can easily pass at the narrowest point. How is it determined which is the stand on vessel? Is there a legally mandated protocol?
I suppose in reality, both skippers would be watching their AIS and would be on the radio sorting things out.
A pretty easy one to Google
if you want to bury yourself in maritime lawyers' opinions! But actually you got the answer...they must communicate.
Ultimately, as with all COLREG, context and the interplay of all the rules, including where local rules overlay are part of the challenge.
Firstly you need to decide if you mean 'Constrained by Draught' in accordance with COLREG 3 where the vessel(s) can't deviate, or just the broader fact that we all stick to channels.
Second remember that the CBD rule only applies to power driven vessels, so sailing vessels not operating machinery are a separate issue.
Third apply COLREG 9 to narrow channels and local variations (see this to touch on what others are referring to about specific US cases https://www.law.cornell.edu/cfr/text/33/83.09
Also consider as some have whether they are 'in sight of one another'.
Ultimately, it comes down to the fact that lawyers, like naval architects, don't necessarily go to sea much and are very good at the after action attribution of blame or engineering a solution, but not so much help on the spot. So in your scenario a risk of collision
does exist, the rules don't cover it enough and therefore they need to act to avoid collision
, in this case best enabled by direct communication. To be clear however, calling securite doesn't give you any rights, it is a warning message and the two pilots or masters still need to negotiate. Even with local rules about upstream/downstream, the right answer might be for the one most safely able to slow or stop and maintain steerage gives way.