Established as a mechanism to avoid collisions at night, navigation lights not only make your boat visible to others at a distance, they also allow an observer to determine your direction of travel relative to themselves, as well as whether you are under power or sail.
If you are new to boating, it's important to know that the USCG has specific requirements that all boats need to meet – often depending on the size of the vessel. Below is a summary of the requirements for navigation lights if you are operating your vessel between sunset and sunrise as well as common compliance issues to keep in mind to avoid a fine.
Please note that each state may have additional laws above and beyond these federal requirements, and we do not go into those here. To ensure compliance with state boating laws, you should contact the appropriate boating agency in your state.
While underway – these vessels must display a green sidelight at the starboard side and a red sidelight at the port side. These sidelights should show an unbroken light from dead ahead to 112.5 degrees on either side and should be visible at a distance of 2 nautical miles (NM). Power vessels less than 65.6 ft (20 m) in length may combine the sidelights in a single (“bi-color”) fixture carried on the fore-aft centerline of the boat.
You must also carry an aft facing white stern light, as nearly as practicable at the stern, so its beam is an unbroken arc of 135 degrees showing 67.5 degrees on each side of the vessel (typically mounted on the centerline). This light must also be visible at a distance of 2 NM.
A forward facing white “masthead” light must be carried on the centerline of the boat. Often mounted on a pole or the front of the bridge, the masthead light must show an unbroken beam of 225 degrees (112.5 degrees on either side of the boat) with a visibility of 3 NM, and should not be obscured by any equipment while underway. Not mounted literally at the top of the mast, the masthead light has specific height requirements which depend on the length and beam of the vessel, and place this light higher than the side lights. Refer to your copy of the USCG Navigation Rules and Regulations Handbook (legally required on all boats of this size, and often referred to simply as the “Rules”), Annex I, Section 84 for specific height requirements for your vessel.
While underway, these vessels must display the same side and stern lights as above, but these lights are only required to have a visibility of 1 NM along with a masthead light with a 2 mile visibility.
On power driven vessels (only) less than 39.4 feet, the masthead and stern functions may be combined into a single all-around white light (225° plus 135°). If used, make sure the all-around white light is at least 3.3 feet (1 meter) above your sidelights. When not underway, this all-round combination light can also be used as an anchor light, see below.
For power boats less than 23 feet (7 meters) that do not exceed 7 knots boat speed, you may display just one all-around white light. However, sidelights are recommended.
While under sail, you have several options for displaying navigation lights:
Visibility of navigation lights for sailboats this size should be as follows:
NOTE: A sailboat operating under power at night - whether the sails are set, or not – is required to follow the same rules as a power boat, as outlined above, since they are no longer entitled to the sailboat's usual right of way privileges due to restricted maneuverability. For this reason, most sailboats will often comply with option 1 above, and will mount a masthead (or “steaming”) light on the front of the mast. Although called a “masthead” light, this light is not literally carried at the top of the sailboat's mast. Instead there are specific minimum height requirements for various length sailboats, which will be found in Annex I, Section 84 of the Navigation Rules and Regulations Handbook.
It's also important to note that the function of an all-round white light located at the top of a sailboat mast is an anchor light, not a masthead light. This light should not be used when sailing or powering at night – it should only be used at anchor.
While under sail, if possible, you should display lights as stated in options 1 or 2 above for the greatest visibility and directional awareness to others. If that is not possible, the Rules state, “the vessel shall exhibit an all-around white light or have ready at hand an electric torch or lighted lantern (flashlight) showing a white light which shall be exhibited in sufficient time to prevent collision.” If you are in this situation, it's best to shine the light against your sail to make the biggest impression possible to avoid collision.
While it is not technically required for recreational vessels to exhibit an anchor light unless they are outside of a designated anchorage, or anchored in a narrow channel or anchorage where other vessels normally navigate, the Rules state that “a vessel of less than 50 meters in length may exhibit an all-around white light where it can best be seen”.
At Fisheries Supply, we are firm believers that showing an all-around white light at the highest possible point on your vessel is an important safety measure. You never know when another boat might be on the move and will need to see you on a dark night – so why not make it easier on everyone and let them know you are there?
When anchored in a crowded anchorage with its attendant high speed vessel traffic, some skippers opt to show a light at deck level – perhaps a cabin or cockpit light – in addition to their anchor light, to alert speedboat operators who might not notice a light at the top of a tall mast. If you are concerned about the overnight power draw of lights displayed while at anchor, there are now plenty of LED options available – some of which even turn themselves off when the sun comes up.
The following items are often causes for the issuance of citations by U.S. Coast Guard field inspectors:
You can find all the relevant specifications for the navigation lights we sell on the Fisheries Supply website, as well as in our print catalogs. We stock lights from a wide variety of manufacturers, including Aqua Signal, Hella, Lopo Light, NaviSafe, OGM, Perko and Sea-Dog.
If you are simply replacing or upgrading an existing light fixture, your task is relatively straightforward. If, however, you are designing a new installation, you should be forewarned that the complete set of Rules is complex and somewhat difficult to interpret without experience. We urge you to consult a professional to ensure that your installation is both safe and legal.
We hope this helps you determine what you need on your boat, but if not – feel free to contact one of our product experts for clarification at (800) 426-6930.