Light Up The Night

The right navigation lights are essential to safe piloting after dark.

By Daniel Rutherford
Published: July 2014

Photo of a man overboard module blocks stern light
Photo: Daniel Rutherford
This man-overboard module prevents the stern light from being seen from the port side.

One last case to help illustrate just how important the proper display of navigation lights is: In 2012, there was a collision between a sport-fisherman and a sailboat off the coast of Delaware. (opening photo) It was a dark, almost moonless night, but the weather was clear and visibility was unlimited. Both vessels were equipped with and operating their radars, and both vessels were equipped with and running their navigation lights. But somehow they found each other in that big ocean, the powerboat colliding with the port bow of the sailboat, resulting in injury.

The investigation revealed that the powerboat's navigation lights were all energized and properly displayed. The sailboat was fitted with all required lights and she was under power, meaning she had to show the lights of a powerboat. She had, just prior to the collision, switched on all of her navigation lights. Unfortunately, the investigation also revealed that the stern light was mounted in such a position as to be obscured from the port side by a MOM and there was evidence to show that the combination bow light may not have been illuminated because one of the wires leading to the light at the base of the bow rail was corroded and had parted. This case went to court and settled on a mutual fault basis showing that despite the burdened vessel (the powerboat in this case) not giving way, there was fault attributable to the privileged vessel (the sailboat) because she, too, was in violation of a navigation rule.

See And Be Seen

Now that you know how dangerous incorrect or inoperative lights are, here is what I suggest you do at your first nighttime opportunity. Take your boat out to a safe anchorage, turn off all of the deck and cabin lighting, and turn on all of the navigation lights. From a dinghy or another vessel, circle your boat and make sure that all of your lights are in compliance with the COLREGS.

First, see if they are all working. If not, check the wiring connections to the lights. Make sure those connections are clean, intact, and watertight. Check the bulb and filament. If the bulb has a cloudy appearance, a loose filament, or any indication of burning, replace it. Check the bulb contacts and clean them (a small piece of emery cloth is perfect for cleaning the contact surfaces). Now make sure that the light is mounted correctly so that it projects the proper arc of visibility.

Photo of a combination sidelight obscured by roller furling
Photo: Daniel Rutherford
This red/green sidelight is barely visible on deck, let alone by someone on another boat.

Next, check to see that they are bright — most nav lights have to be seen from two miles away. If they seem dim, remove the light's lens (if possible) and check to be sure that it is clear and not hazed over by UV degradation. Often, lights mounted on rails are hung by straps or fittings that allow the light to sag downward over time. The lens needs to be perpendicular to the waterline unless otherwise stated in the mounting instructions. Perhaps most importantly, is there anything hanging over the light or obstructing its full arc of visibility? Navigation lights are useless if they can't be seen.

Each time before you venture out at night, don't just flip the switch and assume the lights are on. Visually check and examine the lighting to make sure it is both on and visible. Remember, your navigation lights are how you are going to be seen (or not seen) by others.End of story marker

Daniel K. Rutherford is president of Ocean Marine Specialties, Inc., a marine consulting firm that specializes in marine accident reconstruction and claims investigations. He is a Certified Marine Investigator and Licensed Private Investigator. He has been investigating marine cases for over 30 years.

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