Colregs question :)

Hello again, a bit off topic (unless you paddle near shipping channels at night), but
googling examples whilst studying for my boat licence, i came across this anomaly:
in vessels > 50m, the night lights on the masts in some examples have the bow light higher than the stern. i am presuming there are different standards, maybe 1 for North America and 1 for europe? but arent these supposed to be international regulations?

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(ii) a second [masthead light]( abaft of and higher than the forward one

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are 2 versions of this rule?
thanks,
r

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For steaming lights, the forward light must be lower than the stern light. At anchor, the forward all-round light is higher than the stern all-round light. Could that be the confusion? When in doubt, go by the text.

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That definately explains it.

But who came up with this scheme?

Its like a car owner moving his tail lights assembly depending on if he is parked or not.

If you see a ship from miles away,and all that are visible are the two top white lights, you cant really infer much.

If they were always at a fixed height,then they would convey more information.

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They been at it for a long while so I’m thinking there is some logic.

A masthead light is visible at 6 miles. So depending on nighttime conditions if you see a light more than 3 miles away, it should be a steaming light. Nav lights will then appear at 3 miles and provide more information. If you first see all-round lights at 3 miles, you know it is anchored. If you see one white at three miles, it’s more likely a smaller boat. Most ships anchor in designated anchorages near ports, so the taller forward light (and where the black ball goes) let’s you know where the pointy end of the boat is and importantly, where it’s rode lies.

Having forward and aft steaming lights acts as a range. So along with the red/green telling you which side of the boat you’re looking at, the white lights give some sense of relative angle.

Of course with radar, AIS and ARPA you almost wonder why bother with lights… until none of those things work.

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Not for a sailboat under power. My stern light is on the stern rail. Steaming light is halfway up the mast. But neither are all around lights - you’ll see one or the other (and one side light) depending on the angle.

Aren’t lights fun??

@Randall , what license are you studying for? I took the course for a 25 ton Master’s license years ago but never did the paperwork.

Yes. But I was focusing on 50 m or longer as the OP was discussing. We can get really bogged down if we want to discuss all the permutations of lights and vessels. It gets fun when dealing with tug and barge, fishing, dredges, submarines all in one night.

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