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Let There Be Light

Nav lights can ensure the safety of your crew. Know how to use and care for those on your boat
When running at night, it’s easy to become confused by land-based fixtures  such as traffic lights and car taillights.

When running at night, it’s easy to become confused by land-based fixtures such as traffic lights and car taillights.

The tuna were biting offshore and the boat was loaded with bait, tackle, crushed ice and an excited charter party ready for action. As the fish were taking up residence in the Hudson Canyon off the New Jersey coast 75 miles from Manasquan Inlet, the strategy was to sneak out in the dark and get lines in the water prior to first light.

Just before unleashing the 52-foot boat from the dock I realized my starboard green navigation light was out. Despite gentle persuasion with my fist, it remained extinguished. A rushed inspection of the boat did not turn up a replacement bulb, but I found what I needed in my tackle locker: green Cyalume glow sticks, which were left over from a swordfish trip.

I grabbed two sticks, snapped both to activate the chemical formula and attached them to the side of the flybridge wing with duct tape. We were ready for a night run offshore. As we pulled out of the inlet, I reminded myself to pay special attention to the starboard side of the boat, since my light remedy was not exactly legal by Coast Guard standards.

Navigation lights perform multiple tasks and are required to be lit from sunset to sunrise, as well as during periods of reduced visibility in rain, fog, smoke or snow. The lights not only alert other boats to your position, they indicate your speed and course intent, as well as your station, be it fishing, anchored, sailing or simply drifting along. Since my run offshore would see me through four inbound and outbound shipping lanes, and past a fleet of commercial scallop fishing boats and other recreational vessels targeting tuna, it was necessary for my boat to be seen by other vessels.

Colored sidelights are designed to show unbroken light from straight ahead to 22.5 degrees abaft the beam, on both sides of the boat. A masthead white light shows 225 degrees forward and the white sternlight shines 135 degrees aft. When combined, these two lights offer 360-degree coverage and can double as an all-round anchor light.

Here are a few basics about navigation lights. If you’re running and see red and green lights and a white light, that boat is forward of your boat, and coming toward you. If you only see a white light, you are closing in on that vessel, which may be underway or anchored.

A more important element is a light’s intensity, which is based on the length of the vessel. Vessels less than 12 meters or 39.4 feet in length carry a white mastlight visible for two miles, green and red sidelights visible for one mile and a white sternlight visible for two miles. Boats longer than 12 meters but less than 50 meters (or 164 feet) ramp it up a bit to 2-mile visibility for the side and sternlights and 3 to 5 miles for the masthead light. In Navigation Rules & Regulation Handbook, Rule 20, which applies to International and Inland waters, states that during sunset to sunrise no other lights can be displayed if they can be mistaken or confused with the applied navigation lights.

On our way to Hudson Canyon a pair of scallop boats along the 40- to 50-fathom edge were lit up like a used car lot as the fishermen worked the decks. It was difficult to discern a red or green sidelight, which would have indicated the boats were underway. Typically, commercial fishing boats trawling at night also display a green-over-white light to indicate station and to alert passing boats of intent. Nevertheless, we passed the boats with mileage to spare and preserved our night vision.

An hour later another boat we had been tracking on radar quickly approached from the stern. The boat—a large center console with bow and spreader lights, underwater lights and a bright flood light—overtook us on the port side. The boat’s operator was obviously in a hurry. The boat was moving so quickly I never saw its navigation lights, even though it passed us no more than 100 yards away. Maybe the operator forgot to turn them on, or perhaps the colored sidelights were overwhelmed by all of the white lights. It reminded me that the location of nav lights has a big impact on their visibility.

Stay vigilant when running after dark. In open water where boats often keep their distance the operator has a little more time to discern the proximity of other vessels. Closer to shore, however, it is easier to become confused by land-based fixtures such as traffic lights and automobile taillights. I recall an incident in my home waters when a boater mistook traffic lights for the inlet jetty lights. Fortunately, at the last minute, he was able to turn away from the surf line and get back into deeper water to make safe passage through the inlet.

Maintaining your boat’s nav lights is critical to your crew’s safety. Fortunately, this doesn’t require too much work. Get in the habit of working the lights each time you go aboard. Move the switch and activate the circuit to help keep things flowing properly. On my small boat I make it part of seasonal maintenance to pull the light apart, check each bulb and apply a coat of light grease to the base—saltwater corrosion is an ongoing adversary in the fixture. Since the plastic globe often dulls under constant sunlight, I like to polish both sides of the globe with Novus 1 or a similar plastic polish.

When maintaining nav lights, be careful how you disassemble the housing to access the bulb. Many nav lights are difficult to reach and have metal or plastic housings with small screws holding everything together. It is very easy to burr up the heads and/or drop them overboard, or have the globe slip from your grasp if you rush the process. Pay attention to the wire and terminals, and be sure the light goes back together the way it came apart.

If you don’t have spare bulbs on the boat, note the bulb number when you are cleaning the light and put it on your shopping list. Replacement bulbs can sometimes be difficult to find, and marine stores don’t always stock a wide variety. If that is the case, consider replacing the old bulb lights with new, high-intensity LED navigation lights. On the water, to be seen is to be safe. 

This article was originally published in the January 2021 issue.



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