Imagine that it’s a pitch black night, and you are exiting Channel Islands Harbor in Oxnard. You see these lights up ahead. What kind of vessel is this? Do you give way to it, or do you stand on? Which side should you pass on?
This dredge is working in the entrance to Channel Islands Harbor. In the daytime it shows the day shapes for a vessel restricted in her ability to maneuver – the Ball, Diamond, and Ball above the wheel house. At night, she shows Red, White, and Red lights in a vertical line.
The safe side to pass on is indicated by the two black Diamonds on the right side of the wheel house, though the lower one is obscured. At night, this is indicated by the two Green lights in a vertical line.
The danger side is indicated by the two black Balls on the left side of the wheel house, indicated at night by two red light in a vertical line.
In the Navigation Rules, Rule 3 General Definitions section (g) states in part, “The term ‘vessel restricted in her ability to maneuver’ means a vessel which from the nature of her work is restricted in her ability to maneuver as required by these Rules and is therefore unable to keep out of the way of another vessel.”
This is a good example of a vessel restricted in her ability to maneuver. You can see it has nothing to do with being big, slow, or difficult to turn or stop. This vessel has gear in the water sucking sand off the bottom, and it is connected to a huge hose that runs ashore where the sand and water is pumped out. This vessel simply cannot maneuver for you, and that is what “restricted in her ability to maneuver” means.