The US Coast Guard has developed an elaborate scheme of navigation lights for boats and sailboats of all sizes on the York River and around the world. Thay way, everyone can recognize each other at night and tell what direction they’re going.
The easiest example is the one here of a sailboat with red, green and white lights. Note that the arc of each light does not cross over into another light, so that at most you’ll only see two lights. If you look over your port bow and see green/white moving, you can assume the boat is about to cross your bow from the left. But if you look starboard and see red/white approaching, then the boat is about to cross your bow from the right. And if you see only white, then you are approaching another boat from behind and should take care to slow down and indicate which side you intend to pass on.
Other white lights kick in for when a sailboat lies anchored or steaming. The anchor light sits atop the mast while the steaming light is mid-mast. They all have meaning, and sailors need to fire up the proper lights to match the occasion.
Multiple lights and layers of lights reflect larger vessels. During the testing phase for the USCG captain’s license, students observe thousands of patterns quickly to identify the type of ship and where it’s going. Albeit grueling, the lessons sink in and begin to build instant recognition. Time matters at sea, especially at night or during limited visability. Students at Chesapeake Marine Training Institute become so adroit that they spot errors in the tests.
There’s a lot more to it, of course, but the system is logical and tested all the way up to commercial freighters. Some thought is required, not just memorization. Learning the nav lights makes sailing safe, comfortable and unique fun at night.
Having said that, we generally avoid sailing at night for reasons having nothing to do with lights. There is great apprehension about running through a crabpot line and fouling the prop. But that’s another story.
Check out the video below for a simplified course in Nav Lights.
Let’s Go Sail
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