1 pt each

Why would three lights be used?

Don' t know.

This is a tough one. I'll reveal the answer.

It it fairly common to find three lights constituting
two ranges, at the bend of a channel. The first
range is the normal type.

The second range uses one of the first lights and
is a "look behind you" range. After the bend in the
channel.

Does that make sense?

I mentioned it because it is something some of my
student have had trouble with in chart work

However, my question was, perhaps, confusing.

Perhaps I should phrased the question.

How can three lights be used to establish two ranges?

Bart