Boating at night is a challenge that should not be taken lightly. Unlike nighttime in the city, which is saturated by lights, at sea the darkness can be almost total. Therefore, it’s better to boat by daylight, but sometimes you may need to sail at night and you should be prepared for when that moment comes.
The basic stuff
First of all, you should know the rules for nighttime navigation. There’s always a chance of running into another boat and you need to know what the protocol is for that situation so you can act accordingly.
If you get the chance of choosing when your nighttime adventure will be, try choosing a clear night with a full moon, so visibility is the best it can be (beware of the tides, though!). However, sometimes it may be impossible to pick the night. Maybe you have to reach your destination before the next day and the moon hasn’t reached its fullness. In those cases, you should be extra careful. And regardless of the conditions, always steer slow, ideally at pre-planing speed.
The trick is in the lights
Nighttime navigation comes down to light. To succeed, you need to learn how light works, how it can help you or hinder you and the many lights you can find within or without your boat.
When navigating at night, you may be tempted to blow up all your lights to compensate for the darkness surrounding you. You shouldn’t do that. Your eyes automatically adjust to the amount of light around them, so if the lights inside your boat are turned up to the maximum, your eyes will adjust to that brightness and will be blinded when you look beyond into the dark. It’s better to dim all the lights on the boat so the contrast between them and the night isn’t so stark and your night vision isn’t impaired.
If you have devices whose lights you can’t afford to turn off, like the chartplotter or the VHF display, you can cover them with a towel and only uncover them when you need to look at their screens. It’s also advisable to look at the chartplotter as little as possible: even when fully dimmed it could still reduce your night vision, so rely more on a traditional compass and only look at the chartplotter when strictly necessary.
The same thing goes for the docking lights and spotlights. They may help you see a couple of dozen feet ahead, but beyond that the night will be the same and, as your eyes adjust to them, you won’t be able to see into the darkness for landmarks or obstacles. These lights should be used respectively for docking and for locating reflective markers or objects you’re trying to find.
Know every light
That goes for the lights of your own boat, but you will also find many lights outside, and they can give you information about your surroundings. Every boat has a set of navigation lights, so you will know what kind of vessel it is and where it’s coming from. Sidelights will tell you which side of the boat you’re looking at: if they are green, it’s the starboard and if they are red, it’s the port. There’s also the sternlight, a white light which can be seen from behind every boat, and the masthead light, a white light that it seen from the front and is only used by power vessels. Together, these lights will let you know what you’re facing and what course of action you should take.
You will also find many lights along the shore to help you guide your course, like buoys and lighthouses. These lights have many meanings and you should be clear on what they are. A good idea is to make a list of lights and what they indicate. Avoid using complicated notations, because when you see a light you don’t know or don’t remember, you need to understand it as fast as possible.
Sources: Boat-ed, Practical Boat Owner, Boats.com