Figure 4-01 What do you make of this pattern of navigation lights? What action do you take? It’s an underway fishing vessel engaged in trawling as viewed from its starboard side. You have to alter course, speed, or both to avoid both the vessel and its nets.
Navigation Rules:
Lights & Day Shapes
Navigation Lights & Day Shapes Required by the U.S. Inland Navigation Rules for Vessels of All Types • The International Navigation Rules & How They Differ from Those for U.S. Inland Waters
The NAVIGATION RULES, often referred to unofficially as the RULES OF THE ROAD, are sets of statutory requirements enacted by Congress to promote the safety of navigation. The rules consist of requirements for navigation lights and day shapes that are discussed in this chapter. They also include steering and sailing rules, sound signals for both good and restricted visibility, and distress signals, all covered in Chapter 5.
There are different sets of rules for international and inland waters, with some local variations in the latter. The first International Rules of the Road were established in 1889; the most recent ones, titled the International Regulations for Preventing Collisions at Sea, were adopted in 1972. These are called the 72 COLREGS by the U.S. Coast Guard. Requirements generally apply to all boats of any size, unless specific sizes of vessels are stated to have differing requirements.
The 1980 U.S. Inland Rules
The 1972 International Rules are unique for the U.S., because for the first time they have the status of an international treaty; previous sets of International Rules had the status of an international agreement. A treaty is more binding on a country, offering less flexibility and requiring stricter compliance with its terms. A key provision of the 1972 International Rules was the requirement in Rule 1(b) that any national rules for internal waters “shall conform as closely as possible” to the International Rules. The first result of this requirement was that the U.S. Inland Rules no longer applied out to the offshore “boundary lines” but were effective only shoreward of new “demarcation lines” (see Chapter 2.) The longer-term effect was the passage by Congress of the INLAND NAVIGATION RULES ACT OF 1980, which unified the previously separate Inland, Great Lakes, and Western Rivers Navigation Rules and their respective supplemental Pilot Rules.
State and local authorities may also issue regulations relating to boating, but these seldom relate to navigation lights and shapes.
Foreign Waters
Some foreign nations have their own set of navigation rules for their internal waters. In Canada, these are the Collision Regulations: International Regulations for Preventing Collisions at Sea, 1972, with Canadian Modifications. Many other countries have no national rules, and in these the COLREGS govern on their internal as well as on external waters.
Sequence of Consideration
Most recreational boaters in the United States use their craft on waters of rivers, lakes, bays, and sounds that are governed by the U.S. Inland Navigational Rules, and for this reason primary consideration will be given to these rules, with the International Rules being presented only in terms of their differences from the Inland Rules. The International Rules apply, however, to all vessels once they clear the jetties or headlands at a harbor entrance. Indeed, these International Rules even intrude into harbors, bays, inlets, and rivers in some areas along the New England and Northwest coasts and in the lower Florida Keys. Check your coastal chart for the location of the demarcation lines.
The consideration of the Rules of the Road in this chapter and in Chapter 5 is not complete; it focuses on the points of greatest concern to boaters.
Numbered Rules
Both the U.S. Inland Rules and the International Rules consist of major subdivisions: Part A—General; Part B—Steering & Sailing; Part C—Lights & Shapes; Part D—Sound & Light Signals; and Part E—Exemptions. (Part E provides specific temporary and permanent exemptions for existing vessels to permit a smooth transition from the previous requirements for lights and sound signals. Most of these exemptions have now expired.)
Within both sets, rules are numbered from 1 to 38, with subparagraphs such as (a), (b), (c), and still lower levels indicated by (i), (ii), (iii). Rules that are identical, or nearly so, in both sets carry the same numbers. There is no rule in the U.S. Inland Navigation Rules corresponding to International Rule 28, but in order that parallel numbering can continue, that number is included with no entry.
Indication of References
In the discussions in this chapter and Chapter 5, numbers and letters shown in brackets are references to the applicable rule. References to annexes are indicated by a Roman numeral, since the annexes to both sets are so designated; specific paragraphs and subparagraphs are noted by numbers and letters as appropriate. These references are shown to facilitate looking up the exact language of the rules and annexes in the Coast Guard publication Navigation Rules and Regulations Handbook (for purchasing, see Know the Navigation Rules text box).
KNOW THE NAVIGATION RULES
On inland waters, each operator of a self-propelled vessel, power or sail, state registered or documented, 12 meters (39.4 ft) or more in length must carry on board and have available for ready reference a copy of the Inland Navigation Rules. [1(g)] Although the Pilot Rules do not explicitly say so, it is reasonable to interpret this requirement to mean an up-to-date copy of the Rules.
The official text of the U.S. Navigation Rules, as well as the International Rules, is contained in the Coast Guard publication entitled Navigation Rules and Regulations Handbook. This small book carries the numerical designation of Commandant Instruction (abbreviated COMDTINST) M16672.2x, where “x” is a letter denoting the specific revised edition. This book also contains sections on the demarcation lines, penalty provisions, vessel bridge-to-bridge radiotelephone regulations, and a metric conversion table.
Changes in the Navigation Rules do not occur often, and when they do, they are usually minor in nature. Such changes are published in Notices to Mariners as they occur, and subsequently in a revised edition of the book. Commercially published versions of this book may be available with changes promulgated subsequent to the date of the official version.
Copies of Navigation Rules and Regulations Handbook can be purchased from some local sales agents for nautical charts or by mail, phone, or via the Internet from the Government Printing Office (Stock Number 050-012-00517-6); phone 866-512-1800, fax 202-512-2104; http://bookstore.gpo.gov. The price was $25 as of early 2017 but varies from time to time; credit cards are accepted. A current electronic copy can be downloaded from the Coast Guard Navigation Center web site at http://www.navcen.uscg.gov/?pageName=navRuleChanges.
Why Navigation Lights & Day Shapes
On a vessel, NAVIGATION LIGHTS are lights shown that are of specified color (white, red, green, yellow, blue), arc, range of visibility, and location, as required by law and regulations. Their basic purpose is to prevent collision by alerting each vessel to the other’s presence; see Figure 4-01. Lights also indicate the relative heading of one vessel as seen from the other, and give clues to its size, special characteristics, and/or current operations. Most important is its orientation with respect to your boat—a fact you must know to determine which is the stand-on vessel (as defined on page 150).
Navigation lights are sometimes referred to as RUNNING LIGHTS (those shown underway) and RIDING LIGHTS (those shown while at anchor or moored), but this terminology is unofficial and does not appear in the Navigation Rules.
In the language of the Navigation Rules, SHAPES are objects of specified shape, size, and placement on a vessel, as required by rules and regulations; all are black in color. These are often called “day shapes,” as they serve some of the same purposes by day that navigation lights do by night; see Figure 4-02. There are no day shapes corresponding to the basic running lights, as the relative aspect and motions of two vessels can be determined by observation. Rather, day shapes are used to indicate special situations such as being anchored or engaged in fishing, as well as some conditions not detectable by eye such as a sailboat with its sails up but with its engine also in use (such a craft is regarded as a power-driven vessel and is not entitled to any of a sailboat’s right-of-way privileges merely because its sails are up).
Figure 4-02 During the day, when lights would be ineffective, shapes (note the black balls and diamond aft of the mast) are used to indicate special vessel status. Other information that is provided at night by lights—type of vessel, size, and relative bearing—can be determined by direct observation in daylight.
Importance of Knowledge
Knowledge of navigation lights is important to a small boat skipper for two separate but equally important reasons. First, he is legally responsible for his boat displaying lights of the proper color, intensity, locations, and visibility. Although as of November 2003 manufacturers must install only certified navigation lights on new boats, craft built before that date may or may not have lights that fully comply with the legal requirements. Thus a boat owner must know the requirements of the applicable Navigation Rules and check that his boat fully complies. If it doesn’t comply, it is he—not the boatbuilder—who will be cited by the Coast Guard and possibly fined. He must also know which lights to turn on (and which not to turn on) for various situations, and when.
Second, he must depend on his knowledge of navigation lights for the safety of his boat when operating at night. Quite often, all the information available about another vessel is derived from interpreting its navigation lights. There are many lights and possible combinations; often a quick decision is needed, with no time to go “look it up in the book.” Know the lights shown on boats and ships. Even in the daytime and with good visibility, the day shapes carried by another vessel will give you information about its activities or limitations that you could not determine from simple observation. Know day shapes as well as lights.
THE U.S. INLAND NAVIGATION RULES
The U.S. Inland Navigational Rules are applicable shoreward of the demarcation lines separating inland and international waters that have been established at entrances to bays, sounds, rivers, inlets, etc.; see Chapter 2. They are not applicable to waters of harbors that are specifically designated as not covered, as along coasts with many small harbors—including New England and Puget Sound—and especially the harbors of offshore landmasses such as Block Island, Catalina Island, and the lower Florida Keys.
The Inland Rules apply on the Western Rivers and the United States portions of the Great Lakes. They also apply to U.S. vessels on the Canadian portion of the Great Lakes as long as there is no conflict with Canadian laws or regulations. [1(a)]
Basic Definitions
Rule 3 contains general definitions that are used throughout the U.S. Inland Navigation Rules.
Vessel This term applies to every size and description of water craft, including nondisplacement craft (air-cushion vehicles) and seaplanes, used or capable of being used as a means of transportation on water. The term “vessel” includes all sizes without limit, from a dinghy or personal watercraft to a supertanker.
Power-driven Vessel Any vessel propelled by machinery.
Sailing Vessel Any vessel propelled by sail, provided that propelling machinery, if fitted, is not being used. A sailboat or motorsailer using both sail and engine simultaneously is a power-driven vessel for purposes of the Rules of the Road.
Underway A vessel not at anchor, made fast to the shore, or aground. This term applies whether or not the vessel is moving (“making way”) through the water. A drifting vessel is often said to be “underway with no way on.”
Vessel Engaged in Fishing Any vessel fishing with nets, lines, trawls, or other fishing apparatus that restricts maneuverability. It does not include vessels with trolling lines, or drift fishing with hand rods and lines.
Vessel Not Under Command A vessel that, due to some exceptional circumstance, is unable to maneuver as required by the Rules and therefore is unable to keep out of the way of another vessel. Typically, this category would apply to a boat drifting with an inoperative engine or steering system.
Vessel Restricted in Its Ability to Maneuver A vessel that, due to the nature of its work, is restricted in its ability to maneuver as required by the Rules and therefore unable to keep out of the way of another vessel. Typically this term applies to dredges, vessels engaged in laying or repairing submarine cables or pipelines, and vessels engaged in a towing operation that severely restricts the towing vessel and its tow in their ability to deviate from their course.
Visibility Vessels are deemed to be “in sight of one another” only when one can be observed from the other. A vessel is not considered to be “in sight” if it is observed on radar, but cannot be seen visually.
Restricted Visibility Any condition in which visibility is reduced by fog, mist, falling snow, heavy rain, sandstorms, or any other similar cause.
Rule 3 also contains other definitions of interest to boaters. The term SECRETARY means the secretary of the department of the federal government in which the Coast Guard is operating. This is normally the Department of Homeland Security, but in time of war or national emergency, it could become the Department of the Navy by Presidential Executive Order.
Geographic Limits
Although separate sets of Rules of the Road for the Great Lakes and the Western Rivers no longer exist, these terms are still defined in the 1980 Inland Rules, because of certain exceptions and special provisions for specified waters.
The GREAT LAKES are defined as the lakes themselves, plus their connecting and tributary waters, including the Calumet River as far as the Thomas J. O’Brien Lock and Controlling Works (between mile 326 and 327), the Chicago River as far as the east side of the Ashland Avenue Bridge (between mile 321 and 322), and the St. Lawrence River as far east as the lower exit of the St. Lambert Lock.
WESTERN RIVERS means the Mississippi River, its tributaries, South Pass, and Southwest Pass to the demarcation lines for COLREGS waters; the Port Allen–Morgan City Alternate Route; that part of the Atchafalaya River above its junction with the Port Allen-Morgan City Alternate Route, including the Old River and the Red River; and the Tennessee-Tombigbee Waterway. Note that the term “Western Rivers” does not apply to rivers on the West Coast of the United States—such rivers as the Sacramento or the Columbia; the basic Inland Rules are in effect for all rivers emptying into the Pacific Ocean.
There are also portions of certain rivers and waterways that are “waters specified by the Secretary” as subject to different provisions of the Inland Rules. These are delineated in the Code of Federal Regulations, Title 33, and are listed in the Navigation Rules, International—Inland book.
Units of Measurement
Except for distances in nautical miles, linear units of measurement in the 1980 U.S. Inland Rules are given in the metric system. Specifications such as the lengths of vessels or the spacing and heights of lights will thus be in meters. The Coast Guard book on the Navigation Rules referred to earlier contains a conversion table for all metric values used in the rules. In this chapter and Chapter 5, the metric values of the rules are followed by customary (English) units in parentheses.
Navigation Lights
Navigation lights are discussed for various categories and sizes of vessels in the subsections below; they are also presented graphically on Interpreting Navigation Lights.
When Lights & Shapes Are Shown
Vessels are required to show the proper navigation lights from sunset to sunrise in all weather conditions, good and bad. During these times, no other lights that could be mistaken for lights specified in the rules can be displayed, nor any lights that impair the visibility or distinctive character of navigation lights or interfere with the keeping of a proper lookout. [20(a) and (b)]
The Inland Rules also state that navigation lights must be shown between sunrise and sunset in conditions of reduced visibility, and may be shown at any other time considered necessary. [20(c)]
Day shapes specified in the rules must be displayed by day; although not specifically stated, this has been taken to mean from sunrise to sunset. [20(d)]
Figure 4-03 Each type of navigation light covers a specific arc of visibility. Left to right: sidelights, sternlight, masthead light, all-round light. When the arcs are understood, the orientation of the vessel becomes clear.
Light Definitions
Masthead Light A white light placed over the fore-and-aft centerline of the vessel, showing an unbroken light over an arc of 225°, and so fixed as to be visible from dead ahead to 22.5° abaft the beam on both sides of the vessel; see Figure 4-04. On boats less than 12 meters (39.4 ft) in length, the masthead light may be off the fore-and-aft centerline but must be as close to it as possible. [21(a)]
Figure 4-04 A masthead light, shown at center in this photo, is white and covers an arc of 225°. It should be mounted high, but not necessarily at the top of a mast. Directly behind (left) is an anchor light.
As will be seen later, the term “masthead light” is something of a misnomer. More often than not, this light is not at the top of a mast. On motorboats it is often on a short staff on top of the cabin. On sailboats it is usually partway up the mast, and the anchor light or a tri-color light (see Figure 4-09) may be at the masthead.
Sidelights Colored lights—red on port and green on starboard—showing over an unbroken arc of the horizon of 112.5°, from dead ahead to 22.5° abaft the beam on each side; see Figure 4-05.
Figure 4-05 Sidelights (the red and green lights) on a vessel must each cover an arc of 112.5°, but not more. On the boat shown here, the side of the flybridge prevents the sidelight from being seen across the bow, a common failing of sidelights on many small craft. Sidelights must not be placed on the hull below the deck line.
Combination Light On a vessel of less than 20 meters (65.6 ft) length, the sidelights may be combined in a single fixture carried on the centerline of the vessel, except that on boats less than 12 meters (39.4 ft) in length, this combination light need be carried only as close to the centerline as possible. [21(b)] Note that the sum of the arcs of the two sidelights is exactly the same as that for the white masthead light; see Figure 4-06.
Figure 4-06 Vessels less than 20 meters (65.6 ft) in length may carry a combined bow light in place of separate sidelights. Each half covers the same arc as one sidelight, and the total is the same 225° as that for separate sidelights. [I-84.06]
Sternlight A white light showing over an unbroken arc of the horizon of 135°, centered on dead astern; see Figure 4-07. [21(c)]
Figure 4-07 A white sternlight with a 135° arc centered on dead astern covers the directions not covered by the sidelights and masthead light. In boats less than 12 meters (39.4 ft) in length, the sternlight may be combined with the masthead light as a single all-round white light.
Towing Light A yellow light having the same arc as a sternlight, showing 67.5° to either side of dead astern. [21(d)]
All-round Light A light, color determined by its use, showing over an unbroken arc of the horizon of 360°. [21(e)] A large vessel may require two lights on opposite sides of a structure.
Flashing Light A flashing light at regular intervals, at a rate of 120 or more flashes per minute. [21(f)] This high flashing rate is used to lessen any possibility of confusion with quick-flashing lights on aids to navigation.
Special Flashing Light A yellow light flashing at a rate of 50 to 70 flashes per minute, placed as far forward and as nearly as practicable on the centerline of a tow, and showing an unbroken light over a horizontal arc of not less than 180° nor more than 225° centered on dead ahead. [21(g)]
INTERPRETING NAVIGATION LIGHTS
The following pages are designed to help you sort out lights in the dark and guide you in identifying the boats associated with them. Refer to the legend at right: the colored text gives information on the International Rules where they differ from the Inland Rules (otherwise, they agree).
SAILING VESSEL 20 M TO LESS THAN 50 M IN LENGTH
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None. (Masthead lights not used under sail alone.) |
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Separate red and green, 112.5°, vis. 2 mi.; if less than 12 m in length, vis. 1 mi. |
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White, 135°, vis. 2 mi. |
R | Optional addition—two all-round lights at or near top of mast, red-over-green separated by at least 1 m, vis. 2 mi. |
POWER-DRIVEN VESSEL 12 M TO LESS THAN 20 M IN LENGTH (AND VESSEL ENGAGED IN SPORTFISHING, TROLLING, OR DRIFT FISHING)
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White, 225°, vis. 3 mi, at least 2.5 m above gunwale. |
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Separate red and green (or combination), 112.5°, vis. 2 mi. |
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White, 135°, vis. 2 mi. |
R | After masthead light not required. |
LEGEND
For each group of illustrations on these pages, the caption uses icons to give the following information:
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Masthead light (forward) 225° |
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Sidelight 112.5° |
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Sternlight 135° |
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Towing light 135° |
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Special flashing light forward 180° to 225° |
R | Remarks or additional lights |
In addition, indicates a flashing light (180° to 225°) and
indicates a 360° light.
POWER-DRIVEN VESSEL LESS THAN 12 M IN LENGTH (AND VESSEL ENGAGED IN SPORTFISHING, TROLLING, OR DRIFT FISHING)
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White, 225°, vis. 2 mi, may be less than 2.5 m above gunwale, but at least 1 m above sidelights. |
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Separate red and green (or combination), 112.5°, vis. 1 mi, at least 1 m below masthead light. |
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White, 135°, vis. 2 mi. |
R | May be off center if necessary; may show only all-round white light, vis. 2 mi, and sidelights. Same. Less than 7 m and less than 7 kt max. speed, need have only all-round white light, and may have sidelights, if practicable. |
SAILING VESSEL LESS THAN 20 M IN LENGTH
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None. (Masthead lights not used under sail alone.) |
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Separate red and green (or combination), 112.5°, vis. 2 mi.; if less than 12 m in length, vis. 1 mi. |
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White, 135°, vis. 2 mi. |
R | The sidelights and sternlight may be combined in one lantern at or near masthead. As an optional addition, two all-round lights may be carried at or near the top of the mast, red-over-green, separated by at least 1 m, vis. 2 mi. |
If less than 7 m in length, need only have white flashlight or lantern to show.
A sailboat under power is no longer a “sailing vessel” and must show the lights of a power-driven vessel, adding the white forward light.
POWER-DRIVEN VESSEL AT LEAST 20 M BUT LESS THAN 50 M IN LENGTH (AND VESSEL ENGAGED IN SPORTFISHING, TROLLING, OR DRIFT FISHING)
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White, 225°, vis. 5 mi., not more than 1/2 of length aft from stem; 5 m or beam (up to 8 m) above hull. Same; 6 m or beam (up to 12 m) above hull. |
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Separate red and green, 112.5°, vis. 2 mi., at or near sides of vessel; at least 1 m below forward masthead light. Same. Not more than 3/4 height of forward masthead light. |
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White, 135°, vis. 2 mi. (Great Lakes may combine sternlight with after masthead light.) |
R | After masthead light may be shown; at least 2 m higher than forward masthead light. Same. At least 4.5 m higher than forward masthead light. |
VESSEL PROPELLED BY OARS
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None. |
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May show separate red and green (or combination), 112.5°, vis. 1 mi. |
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May show white, 360°, vis. 2 mi. |
R | Need only have white flashlight or lantern to show. |
POWER-DRIVEN VESSEL 50 M OR MORE IN LENGTH
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White, 225°, vis. 6 mi., not more than 1/2 of length aft from stern; 5 m or beam (up to 8 m) above hull. After masthead light required. Same. Not more than 1/4 of length aft from stern; 6 m or beam (up to 12 m) above hull. |
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Separate red and green, 112.5°, vis. 3 mi., at or near sides of vessel; at least 1 m below forward masthead light. Same. Not more than 1/4 height of forward masthead light. |
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White, 135°, vis. 3 mi. |
R | After masthead light required; at least 2 m higher and space of at least 1/4 vessel length (up to 50 m) aft of forward masthead light. (Great Lakes may combine sternlight with after masthead light.) After masthead light required at least 4.5 m higher and 1/2 vessel length (up to 100 m) aft of forward masthead light. |
VESSEL TOWING ASTERN; TOW LESS THAN 200 M OVERALL FROM STERN OF TOWING VESSEL
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Two white, arranged vertically, 225°, vis. determined by length of vessel. |
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Normal for size of vessel, vis. determined by length of vessel. |
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Yellow towing light vertically above white sternlight, 135°, vis. determined by length of vessel. |
R | Towing vessel more than 50 m requires after masthead light; the two lights may be on forward or aft mast. |
VESSEL BEING PUSHED AHEAD OR TOWED ALONGSIDE
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Yellow special flashing light on centerline of vessel being pushed ahead or towed alongside. |
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Normal for size of vessel, vis. determined by length of vessel. |
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White, 135°, vis. determined by length of vessel. (Not on vessels being pushed ahead.) |
R | If more than one vessel pushed ahead, lighted as single vessel. |
VESSEL BEING TOWED ASTERN
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None. |
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Normal for size of vessel, vis. determined by length of vessel. |
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White, 135°, vis. determined by length of vessel. |
R | If more than one vessel towed astern, each lighted as separate vessel. |
VESSEL 50 M OR LESS PUSHING AHEAD OR TOWING ALONGSIDE
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Two white, arranged vertically, 225°, vis. determined by length of vessel. |
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Normal for size of vessel, vis. determined by length of vessel. |
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Two yellow towing lights, arranged vertically, 135°, vis. determined by length of vessel.(No white sternlight.) |
R | No yellow towing lights; normal white stern light. |
VESSEL TOWING ASTERN; TOW 200 M OR MORE OVERALL FROM STERN OF TOWING VESSEL
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Three white arranged vertically, 225°, vis. determined by length of vessel. |
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Normal for size of vessel, vis. determined by length of vessel. |
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Yellow towing light, 135°, over white sternlight, 135°, vis. determined by length of vessel. |
R | Towing vessel more than 50 m requires after masthead light; the three lights may be on forward or aft mast. |
VESSEL ENGAGED IN FISHING OTHER THAN TRAWLING
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None. Replaced by all-round red-over-white lights, arranged vertically, vis. determined by length of vessel. |
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Only when making way. Normal for size of vessel. |
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Only when making way. Normal for size of vessel. |
R | When not actually fishing, normal masthead, sidelights and sternlight for size of vessel. |
VESSEL AT ANCHOR 50 M OR MORE IN LENGTH
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None. |
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None. |
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None. |
R | White all-round light in forepart, not less than 6 m above hull. Second white all-round light in after part, not less than 4.5 m lower than forward anchor light, vis 3 mi. If 100 m or more, deck lights illuminated |
VESSEL ENGAGED IN TRAWLING
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None. Replaced by all-round green-over-white lights, arranged vertically, vis. determined by length of vessel. If more than 50 m, after masthead light abaft of and higher than the all-round green light required; 225°, vis. determined by length of vessel. |
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Only when making way. Normal for size of vessel. |
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Only when making way. Normal for size of vessel. |
R | When not actually trawling, normal masthead, sidelights and sternlight for size of vessel. If less than 50 m, may display after masthead light. |
VESSEL AT ANCHOR LESS THAN 50 M IN LENGTH
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None. |
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None. |
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None. |
R | White all-round light where can best be seen, vis. 2 mi. (Not required if less than 7 m and not anchored in narrow channel or where vessels normally navigate.) [30(e)] |
VESSEL AGROUND
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None. |
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None. |
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None. |
R | Anchor light(s) normal for size of vessel; two all-round red lights, arranged vertically, where can best be seen, vis. same as anchor lights. (Not required if less than 12 m.) |
VESSEL NOT UNDER COMMAND—NOT MAKING WAY
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None. |
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None. |
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None. |
R | Two all-round red lights, arranged vertically, where can best be seen. (If making way, sidelights and sternlight normal for size of vessel.) |
VESSEL RESTRICTED IN ABILITY TO MANEUVER
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When making way, normal for size of vessel. |
R | Three all-round red-white-red lights, arranged vertically, where can best be seen. If at anchor, all-round red-white-red lights in addition to anchor light(s). |
PILOT VESSEL
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None if on pilot duty. Replaced with all-round white-over-red lights, arranged vertically. |
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Normal for size of vessel. |
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Normal for size of vessel. |
R | If at anchor, all-round white-over-red lights in addition to anchor light(s). |
VESSEL CONSTRAINED BY ITS DRAFT
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When making way, normal for size of vessels. |
R | Three all-round red lights, arranged vertically, where can best be seen. |
Lights for Various Sizes of Power-Driven Vessels Underway
The basic navigation lights for a power-driven vessel of less than 12 meters (39.4 ft) in length, when underway, are a white masthead light and a sternlight, each visible 2 miles, plus sidelights visible 1 mile. [22(c), 23(a)] The two white lights may be combined into a single all-round light [23(d)]; the sidelights may be separate or combined.
Masthead Lights
Vessels more than 12 meters (39.4 ft) in length must have a masthead light and a sternlight; the two cannot be combined. The masthead light need not be at the masthead but must meet the placement rules of Annex I.
The masthead light of a vessel 12 meters (39.4 ft) or more but less than 20 meters (65.6 ft) in length must be at least 2.5 meters (8.2 ft) above the gunwale. [I-84.02(c)] On boats less than 12 meters (39.4 ft) long, the masthead light need only be at least 1 meter (3.3 ft) higher than the sidelights; it must be screened if necessary to prevent interference with the helmsman’s vision. [I-84.02(d)] and [I-84.05(b)]
On a vessel 20 meters (65.6 ft) or more in length, the masthead light must be not less than 5 meters (16.4 ft) above the hull. If the beam of the vessel is greater than 5 meters, the height must be not less than the beam but need not be greater than 8 meters (26.2 ft) above the hull. [I-84.03(a)] “Height above the hull” is defined as height above the uppermost continuous deck. [I-84.02(a)]
The masthead light must be in the forward half of the vessel, except that in boats of less than 20 meters (65.6 ft) length, it need only be as far forward as possible. [I-84.03(d)]
A second masthead light is required on vessels of 50 meters (164.0 ft) or more, and may be carried on shorter vessels [23(a)(ii)]. This must be at least 2 meters (6.6 ft) higher than the forward light. [I-84.02(a)(ii)]
When two masthead lights are carried, the horizontal distance between them must be at least one-fourth of the length of the vessel, except that this distance need not in any case exceed 50 meters (164.0 ft). [I-84.05(a)] Exception: Special provisions are made on the Western Rivers and other designated waters for vessels between 50 and 60 meters (164.0–196.8 ft) in length. [I-84.03(e)]
Value of Lights as a Range When two masthead lights are carried they form a RANGE, a valuable aid in determining the relative heading of another vessel when it is first sighted at night. Since these white lights are both brighter and higher than the sidelights, they normally will be seen well before the colored light or lights can be detected and read for their meaning.
The relative location of the two range lights will be the key. Should they be seen one directly over the other, the other vessel is heading directly toward you and danger of collision may exist. Should the lower (forward) range light be seen to the right or left of the higher (after) white light, the other vessel is on an oblique course and the angle can be roughly gauged by the horizontal separation between the lights; see Figure 4-08.
Figure 4-08 When a vessel carries both forward and after masthead lights, these form a central range that is an excellent indicator of its heading as seen from your boat. If the lower (forward) light is to the left of the after light, the vessel is heading to your port. If the lower light is to the right of the other light, the vessel is heading to your starboard. When the two lights are directly in line, one above the other, the vessel is heading toward you. These lights will normally be seen well before the colored sidelights.
Visibility Requirements Masthead lights must have a range of visibility as follows: Boats less than 12 meters (39.2 ft) long—2 miles; vessels of 12 to not more than 50 meters (39.4-164.0 ft) in length—5 miles; except that it may be 3 miles for boats less than 20 meters (65.6 ft) in length; vessels over 50 meters (164.0 ft) in length—6 miles. [22]
In all cases, masthead lights must be placed so as to be clear of all other lights or obstructions. [I-84.02(f)]
Sidelights
Sidelights on a vessel of any length must be at least 1 meter (3.3 ft) lower than the (forward) masthead light; they should not be so low as to be interfered with by deck lights. [I-84.02(g)] On vessels of 20 meters (65.6 ft) or more in length, sidelights must not be forward of the forward masthead light. [I-84.03(b)] On vessels of such size, sidelights must be provided with mat black inboard screens to make the necessary cutoff of light at the “ahead” limit of each arc of visibility. [I-84.09(a)] Smaller vessels also must have these screens, if needed to meet the cut-off requirements, and to prevent excessive spillover from sidelights. A combination light using a single vertical filament bulb and a very narrow division between sectors need not have a screen.
Sidelights must have a range of visibility as follows: boats less than 12 meters (39.4 ft) in length—1 mile; vessels of 12 to 50 meters (39.4-164.0 ft) in length—2 miles; and vessels more than 50 meters (164.0 ft) in length—3 miles. [22]
Sternlights
The Rules and Annex I do not specify a vertical or horizontal placement for a sternlight, except that it be as nearly as possible “at the stern.” [21]
The required visibility for a sternlight is as follows: vessels less than 50 meters (164.0 ft) in length—2 miles; vessels 50 meters (164.0 ft) or more in length—3 miles. [22]
A power-driven vessel operating on the Great Lakes may show an all-round white light in lieu of the normal after masthead light and sternlight. This must be carried in the same position and have the same visibility range as a second masthead light would have. [23(e)]
Lights for Various Sizes of Sailing Vessels Underway
A sailing vessel of any size underway—remember that, if any propelling machinery is in use, it is not a sailing vessel—will carry the same sidelights and sternlight as a power-driven vessel of the same length but will not carry a forward white masthead light. [25(a)]
A sailing vessel may additionally carry at or near the masthead two all-round lights in a vertical line, with the same visibility range as a sternlight, the upper being red and the lower green. [25(c)]
Sailboats Under 20 Meters
If a sailboat is less than 20 meters (65.6 ft) in length, the sidelights and sternlight may be combined into a single fixture at or near the top of the mast where it can best be seen. (The Rules do not so state, but “the mast” can be presumed to be the mainmast if there are more than two masts.) [25(b)] The use of a combination masthead light, however, is not permitted when any mechanical power is being used, since there is no way to carry a white forward light higher than the colored sidelights; see Figure 4-09. Carrying a three-color combination light also eliminates the use of the red-over-green optional light for sailboats, and a set of conventional lights would be needed for use when the boat was under mechanical power.
Figure 4-09 A sailboat less than 20 meters (65.6 ft) in length, while underway under sails alone, may show a tri-color light at or near the top of its mast. This combines the sidelights and the sternlight; no other navigation lights are shown. This light must not be used when under power, whether sails are hoisted or not.
A sailboat less than 7 meters (23.0 ft) long should carry normal sidelights and sternlight; but if this is not possible, it is sufficient to have an electric flashlight or lighted lantern ready at hand to be shown in time to prevent collision. [25(d)(i)] Again, if such a boat is operating under mechanical power, it must show the appropriate lights for a powerboat of its size.
Rowboats
A small boat propelled by oars may show the lights of a sailboat or have handy a flashlight or a lighted lantern to show to prevent a collision. [25(d)(ii)]
Lights for Vessels at Anchor
A boat less than 7 meters (23.0 ft) in length, when at anchor not in or near a narrow channel, fairway, or anchorage or where other vessels normally navigate, need not show an anchor light.
Also, there are locations on U.S. inland waters designated as “special anchorage areas” where anchor lights are not required for vessels less than 20 meters (65.6 ft) long. [30(g)] These special anchorage areas are found frequently off yacht clubs and similar facilities. For a boater, they offer the possibility of legally leaving a boat unattended at a mooring without having an anchor light burning continuously or turning one on each sunset.
In anchoring situations other than those above, vessels less than 50 meters (164.0 ft) in length may show only a single all-round white light wherever it can best be seen [30(b)], or the two anchor lights that are mandatory for larger vessels; see Figure 4-10.
Figure 4-10 A vessel at anchor less than 50 meters (164 ft) in length must show a white all-round light where it can best be seen. Larger vessels must show one such light forward and another aft and lower. There are exceptions for very small boats and vessels in waters officially designated as a special anchorage. The day shape is a single black ball.
When two lights are used, the Inland Rules require a white all-round light in the fore part of a vessel at anchor plus a second all-round white light at or near the stern and lower than the forward light. [30(a)] The forward anchor light must be at least 4.5 meters (14.8 ft) above the other one. If the vessel is 50 meters (164.0 ft) or more in length, the forward light must be at least 6 meters (19.7 ft) above the hull. [I-84.03(k)]
Any vessel at anchor may, and a vessel of 100 meters (328.1 ft) and more in length must, also use the available working or equivalent lights to illuminate its decks. [30(c)]
Vertical Spacing & Positioning
When the Rules require that two or three lights be carried in a vertical line, the lights must be spaced and positioned as follows: for vessels less than 20 meters (65.6 ft) in length, the vertical spacing must be not less than 1 meter (3.3 ft), for larger vessels, the spacing must be not less than 2 meters (6.6 ft). Where three lights are carried vertically, the spacing must be equal. [84.039(i)]
The lowest light on vessels less than 20 meters (65.6 ft) in length must be not less than 2 meters (6.6 ft) above the gunwale; on larger vessels, this height requirement is not less than 4 meters (13.1 ft). [I-84.03(i)] This standard of spacing and positioning applies to all lights arranged vertically (except towing lights), including lights on fishing vessels, vessels aground, pilot vessels, vessels restricted in their ability to maneuver or not under command, and the forward lights of towing vessels. The lower of the two all-round lights required on a vessel engaged in fishing must be at a height above its sidelights not less than twice the distance between the two vertically arranged lights. [I-84.03(j)]
Lights for Vessels Aground
A vessel that is aground must show the normal anchor light(s) plus two all-round red lights arranged vertically. [30(d)]; see Figure 4-11. A vessel less than 12 meters (39.4 ft) in length is exempted from this requirement.
Figure 4-11 A vessel 12 to 50 meters (39.4 to 164 ft) in length, when it is aground, must show a normal anchor light plus two all-round red lights. Smaller craft are not required to show these additional lights; larger vessels, over 50 meters (164 ft), show the usual two anchor lights as well as the red ones. The day signal is three black balls hoisted vertically.
Lights for Towing
Vessels of any size that are either towing another vessel or being towed obviously have, because of this condition, much less maneuverability than vessels proceeding singly. To indicate this situation at night, special navigation lights are prescribed for vessels towing or being towed.
Towing Alongside or Pushing Ahead
A power-driven vessel when pushing ahead or towing another alongside must carry, in addition to its normal sidelights, two masthead white lights in a vertical line with standard spacing and positioning. [24(c)] These lights must be shown, but may be carried either at the position of the normal forward masthead light or that of the after masthead if used. However they are carried, the lowest after masthead light must be at least 2 meters (6.6 ft) above the highest forward light, to form an adequate range. [I-84.03(c)] Under the Inland Rules, in lieu of the normal white sternlight, it must carry two yellow “towing lights” in a vertical line, positioned so as to be showing astern.
When a pushing vessel and a vessel being pushed ahead are “rigidly connected” as a composite unit, they are considered a single power-driven vessel and must position their masthead lights accordingly. This is not the same as a tug lashed to a barge ahead, no matter how tight the fastening cables are pulled in. [24(b)]
In inland waters, vessels towed alongside or being pushed ahead must show their own lights. On a vessel being pushed ahead or towed alongside, sidelights must be shown at the forward end plus a “special flashing light” (yellow) as defined in Rule 21 (g). When towed alongside, a sternlight is added. [24(f)]
Exception On the Western Rivers (except below the Huey P. Long Bridge on the Mississippi River) and on waters specified by the Coast Guard, the prescribed lights for a vessel pushing ahead or towing alongside are only sidelights and two towing lights carried one above the other. [24(i)] It is said that masthead lights are not required on Western Rivers because of the number of low bridges that towboats must pass under.
Towing Astern
If the length of a tow astern, measured from the stern of the towing vessel to the after end of the tow, is 200 meters (656.2 ft) or less, the towing vessel must carry two masthead lights in the same manner as for pushing ahead or towing alongside, plus sidelights, a sternlight, and one towing light above the sternlight. If the length of the tow is greater than 200 meters (656.2 ft), three masthead lights are carried in a vertical line, rather than two. [24(a)]
A vessel towed astern carries sidelights and a sternlight but no white forward lights. [24(e)]
An inconspicuous, partially submerged vessel or object must carry special lights rather than those just described. If it is less than 25 meters (82.0 ft) in beam, it must carry one all-round white light at or near each end; if it is 25 meters (82.0 ft) or more in beam, four all-round white lights at or near corners. If it exceeds 100 meters (328.1 ft) in length, it must have additional all-round white lights placed so that the distance between such lights is not more than 100 meters (328.1 ft). These white lights must be visible for 3 miles. This rule exists to provide for the proper lighting of large liquid-filled bags (called “dracones”), log rafts, and other nearly awash objects.
Multiple vessels or objects towed alongside are lighted as a single vessel or object. [24(f)]
When it is impractical for a towed vessel to carry the prescribed lights, Rule 24(h) directs that all possible measures be taken to light the vessel or object being towed, or at least to indicate the presence of that vessel or object.
Small Boat Towing
Although the 1980 Inland Rules make no special provisions for small boats when towing, Rule 24(j) covers situations where towing is not the normal function of a vessel engaged in such work, and the towed vessel is in distress or otherwise in need of assistance. In this instance, all possible measures must be taken to indicate the relationship between the two boats, including the use of a searchlight to illuminate the towed vessel.
Lights for Special-Purpose Vessels
Specific lights or combinations of lights are prescribed for various categories of vessels, so they may be more easily identified at night.
Fishing Vessels
A vessel engaged in fishing, whether underway or at anchor, must show only the lights specified in Rule 26; see Figure 4-12. Remember, however, that the definition of “fishing” does not include trolling lines.
Figure 4-12 By day, a fishing vessel, whether trawling or fishing by other means, must show a shape consisting of two cones point-to-point without vertical spacing. At night, the special fishing lights are green-over-white for trawling; red-over-white for other fishing methods.
A vessel engaged in trawling—dragging a dredge net or “other apparatus used as a fishing appliance”—must show two all-round lights vertically, green over white, plus sidelights and a sternlight when making way through the water. It must also carry a white masthead light abaft of and higher than the green light if it is 50 meters (164.0 ft) or more in length; shorter vessels may, but do not have to, carry this light. [26(b)]
A vessel engaged in fishing other than trawling shows red-over-white all-round lights, again with sidelights and sternlight, if making way. If there is outlying gear more than 150 meters (492.1 ft) horizontally from the vessel, an all-round white light must be shown in that direction. This light must be not less than 2 meters (6.6 ft) nor more than 6 meters (19.7 ft) horizontally away from the all-round red and white lights. [26(c)]
In both cases just mentioned, the lower of the two vertical lights must be at a height above the sidelights not less than twice the spacing between the two vertical lights. The required visibility range is the same as for sternlights.
A vessel that is fishing close by other vessels also fishing may exhibit the additional signals described in Annex II. These signals would aid trawlers and purse seiners working in groups to coordinate their movements. [26(d)]
A fishing vessel not engaged in fishing will show the normal navigation lights for a vessel of its length. [26(e)]
Pilot Vessels
A pilot vessel, when on pilotage duty, does not show normal lights for a vessel of its size, but rather two all-round lights in a vertical line, white over red, at or near the masthead. These lights have the same visibility distance requirement as a sternlight, which together with sidelights, must be shown when underway. At anchor the pilot vessels show normal anchor lights as well as the white-over-red lights. [29(a)]
A pilot vessel not on duty carries only the normal lights for a vessel of its length. [29(b)]
Lights for Vessels with Limited Maneuverability
The U.S. Inland Navigational Rules prescribe special lights for various types of vessels that have limited maneuverability because of their condition or their operations. [27] A vessel less than 12 meters (39.4 ft) is not required to show these lights and shapes, but may do so. [27(g)]
Vessels Not Under Command
A vessel “not under command”—such as one with disabled engines, or one that for some reason cannot direct its movement in a specific direction—will show two red all-round lights vertically spaced where they can best be seen; see Figure 4-13. When making way through the water, such a vessel must also show sidelights and a sternlight but no masthead lights. [27(a)]
Figure 4-13 A vessel 12 meters (39.4 ft) or more in length and not under command (see text) shows two ball shapes vertically. At night, she shows two red all-round lights, plus sidelights and a sternlight if making way through the water.
Vessels Restricted in Maneuverability
A vessel of any size restricted in its ability to maneuver, except one engaged in mine-clearance operations, will show three all-round lights with standard vertical separations, red-white-red. Underway or at anchor the vessel will also show the usual lights for that status. [27(b)]
A vessel engaged in a towing operation that severely restricts the tow’s ability to deviate from its course will show normal towing lights, plus red-white-red vertical lights. [27(c)] It is not intended, however, that vessels engaged in routine towing operations can declare that they are restricted in their ability to deviate from their course.
In addition to the red-white-red lights, a vessel engaged in dredging or underwater operations involving an obstruction to navigation will also show two vertically spaced red all-round lights on the side on which the obstruction exists and two green all-round lights, one above the other, on the side on which it is safe to pass; these lights shall be at the maximum practical horizontal distance, but never less than 2 meters (6.6 ft) from the red-white-red lights, and the upper light of these pairs must not be higher than the lower red light. A vessel of this category will not show anchor light(s) but will show underway lights, if applicable. [27(d)]
Dredge pipelines that are floating or supported on trestles must display lights at night and in periods of restricted visibility. There must be yellow lights along the pipeline, approximately equally spaced and no more than 10 meters (32.8 ft) apart when a pipeline crosses a navigable channel; when the pipeline does not cross a navigable channel, the lights must be sufficient to clearly show the pipeline’s length and course. Each light must be visible for at least 2 miles all around the horizon, flash 50 to 70 times per minute, and be located not less than 1 meter (3.3 ft) nor more than 3.5 meters (11.5 ft) above the water. There must also be two all-round red lights (not flashing) at each end of the pipeline, 1 meter (3.3 ft) apart vertically, with the lower red light at the same height above the water as the flashing yellow lights. [27(d)(iv)]
Diving Operations
Whenever the size of a vessel engaged in diving operations makes it impractical to exhibit all the lights prescribed in Rule 27(d) above, it must instead show three all-round lights, placed vertically, red-white-red; see Figure 4-14. [27(e)]
Figure 4-14 A boat engaged in diving operations at night that restrict its ability to maneuver must show three lights vertically, red-over-white-over-red. During the day, it must show a rigid replica of the code flag A not less than 1 meter in height; flying a cloth flag is not adequate to meet the requirements of the Rules. Though official only in some states, a flag of red field with a white diagonal stripe is often used by divers.
Mine-Clearance Vessels
A vessel engaged in mine-clearance operations (often called “minesweeping”) will show, in addition to all normal underway lights for a power-driven vessel, three green all-round lights. One of these will be at the foremast head and one at each end of the foreyard. These lights indicate that it is dangerous to approach within 1,000 meters (1,094 yds) of the mine-clearance vessel. [27(f)]
Smaller Boats
Boats less than 12 meters (39.4 ft) in length, except when engaged in diving operations, are not required to show the lights of Rule 27, but larger craft must comply. [27(g)]
Not Distress Signals
The various lights of Rule 27, especially those for vessels not under command, should be understood by other vessels as signals of limited maneuverability, not as signals of vessels in distress and requiring assistance. [27(h)]
Miscellaneous Provisions of the Rules
Rule 1(b) of the Inland Rules allows vessels equipped with lights meeting the requirements of the International Navigation Rules to use such lights on inland waters in lieu of the lights specified by the 1980 Inland Rules. Lights must be complete for one set of Rules or the other—no mixtures. (Consult the Coast Guard publication Navigation Rules and Regulations Handbook for the applicable provisions of the International Rules.) This option is of value to the owners of boats that may be operated outside the Inland Rules demarcation lines at night, since it eliminates any need for making a change in lights when going from one body of water to the other.
The navigation lights of the International Rules are permitted on inland waters, but not vice versa; a boat lighted for the Inland Rules may be in violation when proceeding seaward of the demarcation lines.
Any vessel, when passing under a bridge, may lower any light or day shape if it needs to. When clear of the bridge, the lights or day shapes must be repositioned immediately. [20(f)].
Exemptions for Government Vessels
Any requirements for lights and shapes—their number, placement, range of arc of visibility—do not apply to a Navy or Coast Guard vessel whose department Secretary certifies that its special construction—such as for submarines and aircraft carriers—makes this impossible. In such cases, however, their lights must comply as closely as feasible. [1(e)]
Rule 1(c) allows the use of special station or signal lights by naval ships and vessels proceeding in convoy. These additional lights, so far as possible, shall be such as cannot be mistaken for any lights of the Navigation Rules.
Special Submarine Lights
Because of their low height and close spacing, a submarine’s normal navigation lights are sometimes mistaken for those of small boats, although submarines are large, deep-draft vessels with limited maneuverability on the surface. The Rules do not provide for any special lights for submarines at the surface, but under the authority of Rule 1(e), the United States has established a special distinctive light for its submarines; this light is in addition to all other required lights.
The distinctive light characteristic is an amber (yellow) beacon with a sequence of one flash per second for three seconds, followed by three seconds of darkness; see Figure 4-15. The light is located where it can best be seen, as nearly as possible all around the horizon; it will be not less than 2 feet (0.6 m) above or below the masthead light.
Figure 4-15 Because U.S. submarines are large vessels, but with little above-the-water surface, a special identifying light has been established for them—an all-round flashing amber (yellow) light that flashes once a second for three flashes, off for the next three seconds, then repeating.
Signals to Attract Attention
The Inland Rules authorize a vessel to make light or sound signals to attract the attention of another vessel, provided that such actions cannot be mistaken for one of the normal lights or signals. A vessel may also direct the beam of its searchlight toward a danger, but not in such a way as to impede the navigation of any other vessel. [36] See Distress Signals in Chapter 5, page 173.
Air-Cushion Vessels
An air-cushion vessel, when operating in the nondisplacement mode (“flying”), must show the normal navigation lights for a vessel of its length, plus an all-round flashing yellow light where it can best be seen. [23(b)]. There are no special lights for hydrofoil vessels.
Wing-In-Ground Craft
A WING-IN-GROUND (WIG) craft is defined as a multimodal craft which, in its main operational mode, flies in close proximity to the surface by utilizing surface-effect action. WIG craft look similar to seaplanes, but can only fly close to the surface and are capable of operating at speeds in excess of 100 knots. A WIG craft must show the normal navigation lights for a vessel of its length, and in addition—when taking off, in flight near the surface, and landing—a high-intensity all-round flashing red light. [23(c)] Where it is impractical for a WIG craft to show normal navigation lights, it must show lights “as closely similar in characteristics and position as possible.” [31]
Lights for Seaplanes
A seaplane is defined as including any aircraft designed to maneuver on the water. [3(a) and (e)] Seaplanes, while on the water, are thus in theory required to show the same lights as a ship of the same size. Because this will probably be impractical, the Rules offer an exception allowing them to show lights “as closely similar in characteristics and position as is possible.” [31]
Technical Details for Lights
Annex I to the U.S. Inland Rules also contains highly technical specifications for the “chromaticity” (color specifications) of navigation lights, and for the necessary luminous intensity to achieve the various ranges of visibility specified in the Rules. Specifications are also included for horizontal and vertical sectors, so that adequate light brightness is maintained fully over the specified arc, yet rapidly decreases outside the set limits. The requirements for horizontal sectors are the same for all vessels, but the vertical sector specifications for sailing vessels differ from the requirements for powerdriven vessels. When buying lights, specify the type and size of the vessel they are intended for.
Day Shapes
In the interest of collision prevention and greater overall safety on the water, the Navigation Rules prescribe a number of shapes for certain situations and categories of vessels. Objects of specified shape and minimum size are used in the daytime, when lights are ineffective. The general requirements for the display of shapes are given in the numbered rules, with details of configuration, size, and placement set forth in Annex I. Shapes shall be black and of the following sizes.
Ball Diameter of not less than 0.6 meter (2.0 ft).
Cone Base diameter not less than 0.6 meter ( 2.0 ft) and height equal to base diameter.
Diamond Two cones, each as above, base to base.
If more than one shape is hoisted, they shall be spaced at least 1.5 meters (4.9 ft).
Small Boats Vessels less than 20 meters (65.6 ft) in length may display smaller shapes scaled down to be commensurate with the vessel’s size; the vertical separation may be correspondingly reduced.
Vessels Under Sail & Power
A vessel proceeding under sail in the daytime, when also being propelled by machinery, must carry forward, where it can best be seen, a black conical shape with its point downward. Under Inland Rules only, a vessel of less than 12 meters (39.4 ft) length is not required to exhibit this shape, but may do so. [25(e)] This day shape signals that such a vessel is not entitled to a sailboat’s Rule 18 right-of-way privileges even though its sails are set; see Figure 4-16.
Figure 4-16 A vessel with both sail and mechanical propulsion must show a cone shape, point down. Inland Rules exempt sailboats less than 12 meters (39.4 ft) in length, but on waters subject to the International Rules, all sailboats must comply regardless of length.
Vessels at Anchor or Aground
Although larger vessels must display certain shapes by day whenever they are at anchor or aground, this does not apply to small boats in most situations. Vessels under 7 meters (23.0 ft) in length need show no shape if they are not at anchor in or near a narrow channel or fairway, anchorage, or where vessels normally navigate.
Vessels under 20 meters (65.6 ft) in length need not display shapes when at anchor in a special anchorage area [30(g)]. Vessels less than 12 meters (39.4 ft) in length are not required to show shapes when aground. [30(f)]
In all other situations, vessels at anchor must hoist a ball shape forward where it can best be seen; see Figure 4-17. [30(a)] This is the signal displayed by the large vessels whenever at anchor. Similarly, a vessel 12 meters (39.4 ft) or longer aground must display three ball shapes in a vertical line; refer to Figure 4-11. [30(d)]
Figure 4-17 Vessels at anchor by day must hoist a ball shape. Boats less than 7 meters (23.0 ft) anchored clear of traffic need not show this shape. Craft less than 20 meters (65.6 ft) in length are also exempted if in a designated “special anchorage area” (U.S. inland waters only).
Vessels Towing & Being Towed
Between sunrise and sunset, a power-driven vessel having a tow astern that is longer than 200 meters (656.2 ft) must carry a diamond shape where it can best be seen. [24(a)]
In such cases, the vessel being towed must also show a diamond shape where it can best be seen. [24(e)]
Vessels Engaged in Fishing
Vessels engaged in fishing by day must indicate their occupation by displaying, where it can best be seen, a shape consisting of two cones in a vertical line with their points together (in this case only, no vertical separation between the two shapes). [26(b) and (c)] These shapes are used on vessels engaged in either trawling or in fishing other than trawling (but not on vessels trolling or drift fishing); refer to Figure 4-12.
If its outlying gear extends more than 150 meters (492.1 ft) horizontally from the vessel, a vessel engaged in fishing, other than trawling, will show a day shape of a single cone, point up, in the direction of the outlying gear. [26(c)]
Vessels 12 Meters or More with Limited Maneuverability
A vessel not under command will show as a day signal two black balls one above the other; refer to Figure 4-13. [27(a)] A vessel “restricted in its ability to maneuver” will hoist three shapes in a vertical line, ball-diamond-ball; refer to Figure 4-02. [27(b)]
A vessel engaged in a towing operation that severely restricts the tow’s ability to deviate from its course, will show the ball-diamond-ball shapes, in addition to any other required day shapes. [27(c)]
Vessels engaged in routine towing operations, however, cannot declare that they are restricted in their ability to deviate from their course.
A vessel engaged in dredging or underwater operations when an obstruction to navigation exists will hoist two balls vertically on the side on which the obstruction exists, with two diamond shapes on the side on which another vessel may pass. [27(d)] If the size of a vessel engaged in diving operations makes it impracticable to exhibit these shapes, it shall show instead a rigid replica of the International Code flag A (white and blue, swallow-tailed) not less than 1 meter (3.3 ft) in height, arranged to ensure all-round visibility; refer to Figure 4-14. [27(e)] This requirement for visibility in any direction will normally require multiple rigid “flags” in a crisscross or square arrangement. An A flag—made of cloth—is not an acceptable substitute for the “rigid replica” required by the Rules.
While there is no official recognition in the International or U.S. Navigation Rules for the familiar “diver’s flag”—rectangular red with one white diagonal slash—it is still advisable to fly it in the close vicinity of any persons engaged in diving as a warning to other craft to stay clear; this can be done by mounting the flag on a small float that moves along with the divers. Some state laws require that the red-and-white flag be flown when there are divers in the water; it should not be flown routinely when this condition does not exist. The A flag replica relates only to the status of a vessel and is not required, nor should it be displayed, if maneuverability is not limited, such as by having divers connected by hoses and lines.
A vessel engaged in mine clearance will show three balls, one at the foremast head and one at each end of the foreyard; these have the same significance as the green lights shown at these positions at night. [27(f)]
Pilot Rules for Inland Waters
The PILOT RULES for inland waters under the 1980 Inland Rules are found in Annex V. The Pilot Rules require that a copy of the Inland Navigation Rules be carried on board every “self-propelled vessel” 12 meters (39.4 ft) or more in length. [V-88.05] These are found in Coast Guard publication Navigation Rules, International—Inland, available for purchase from the Superintendent of Documents, Government Printing Office, Washington, D.C. 20401, or from regional GPO Bookstores; Internet http://bookstore.gpo.gov; it may also be available from some local sales agents for charts and nautical publications.
The Pilot Rules contain certain additional provisions for navigation lights:
Law Enforcement Vessels
Law enforcement vessels of the United States and of each state and their political subdivisions, may display a flashing blue light when engaged in direct law enforcement activities. This must be located so as to not interfere with the visibility of the vessel’s navigation lights. [V-88.05]
Public Safety Vessels
Vessels engaged in government-sanctioned public safety activities, and commercial vessels performing similar functions, may display an alternately flashing red-and-yellow light; this must be a single light, not two separate red and yellow flashing lights. Typically, these are small craft patrolling an authorized regatta, race, or similar marine event, and small towing assistance vessels; other examples are fire and rescue boats, search and rescue craft, and medical assistance vessels. [V-88.07]
This special light does not replace—nor should it be located as to interfere with—normal navigation lights. It is only a means of identification and does not convey any special privileges. Vessels showing this light must abide by all applicable Navigation Rules and not presume that they have any precedence or right-of-way.
PENALTIES
The Navigation Rules do not include provisions for penalties, but the U.S. federal law that makes them effective does provide stiff penalties for violations. An important aspect of these penalties that is not widely understood is the concept that the vessel can also be penalized in rem, or “under the law” (see below). Under several penalty provisions, it is possible for the operator, the owner, and the vessel itself to be penalized.
Theoretically, this could result in an owner paying several penalties for the same violation. Additionally, many boating actions could be violations of state or local laws and subject to nonfederal penalties.
Operation in Violation of the Rules
Any person “who operates a vessel” in violation of either the Inland or International Rules, or any regulation issued thereunder—and this includes the various annexes—is liable for a civil penalty of not more than $5,000 for each violation. The vessel may also be subject separately to a similar penalty.
It should be noted that this penalty is not a “fine” requiring conviction in a federal court, but it is a civil forfeiture imposed by the Secretary or his delegate. The penalty may not be assessed until the person charged has received notice of the violation and had an opportunity for a hearing. The Secretary or his delegate may remove or mitigate any penalty assessed. If a penalty, as finally determined, is not paid, the matter can be taken to a Federal District Court for collection and/or appropriate action.
Negligent Operation
Anyone operating a vessel in a negligent manner (which can include a careless action that endangers a person or property) is liable to a civil penalty of as much as $5,000.
Gross Negligent Operation
Anyone operating a vessel in a grossly negligent manner is subject to a fine of up to $5,000 or imprisonment for up to 1 year, or both.
Duties in an Accident
A vessel that is involved in a collision (“marine casualty”) must render assistance to anyone else involved in the accident, as long as such assistance can be done without endangering the passengers, crew, or the vessel rendering aid.
The operator (“master”) must give his or her name and address and the identification of the vessel to anyone else involved in the accident.
Anyone who fails to provide assistance and/or who does not provide proper identification is subject to a fine of up to $1,000, imprisonment for up to 2 years, or both. The vessel is also liable to be fined in rem.
Obligation to Render Assistance
Anyone who encounters another person or vessel at sea who is in need of assistance must render that assistance as long as it can be done without endangering the passengers, crew, or the vessel rendering aid. Anyone who fails to provide such assistance is subject to a fine of up to $1,000, imprisonment of up to 2 years, or both.
The “Good Samaritan” Provision
Anyone who complies with the required duties listed above, or who gratuitously and in good faith renders assistance at the scene of an accident or other boating casualty without the objection of any person being assisted cannot be held liable for any civil damages as a result of rendering assistance, or of any act or omission in providing or arranging salvage, towing, medical treatment, or other assistance where the individual acts as an ordinary, reasonable, and prudent person would have done under the circumstances.
Penalties Against Vessels
In maritime law, a vessel itself can be held to be in violation and be subject to penalties if operated contrary to any provision of the Inland Navigational Rules Act of 1980 or regulations issued thereunder, including the annexes. The same maximum penalty, $5,000 for each violation, can be assessed, and in this case the vessel may be seized and proceeded against in any Federal District Court. The same procedures for due notice and hearings are available to the owner of a vessel charged with a violation as are available to individuals as described above.
The law also allows the withholding or revocation of U.S. Customs clearance for any vessel whose owner or operator is subject to a penalty for violation of the Inland Rules. This is an important consideration for foreign vessels operating in U.S. waters. If penalty proceedings are not complete before the vessel’s sailing date, clearance may be granted upon the filing of a bond or other surety satisfactory to the Secretary.
INTERNATIONAL NAVIGATION RULES
Careful study of the 1980 U.S. Inland Rules of the Road provides an excellent basis for understanding the INTERNATIONAL REGULATIONS FOR PREVENTING COLLISIONS AT SEA, 1972—the formal name for what are generally called the INTERNATIONAL RULES OF THE ROAD, or 72 COLREGS. The International Rules were made applicable to U.S. waters and U.S. vessels by Presidential Proclamation and subsequent Act of Congress. The 1972 International Rules consist of 38 numbered “rules,” grouped together into the same “parts” as for the U.S. Inland Rules, plus four “annexes” (the International Rules do not have Pilot Rules, the fifth annex of the U.S. Inland Rules). Some of these rules and annexes relate to lights and day shapes, and are discussed here. Other rules and annexes are concerned with right-of-way, whistle signals, and distress signals; these are considered in Chapter 5.
Applicability
The International Rules, as established under the U.S. authority, apply to vessels in two situations:
• To all vessels in waters within the United States sovereignty, outside the prescribed demarcation lines at entrances to bays, rivers, harbors, etc.; see page 59. In the absence of demarcation lines, they are also applicable within bays, harbors, and inlets, along specified stretches of coasts, and up the connecting rivers to their limits of continuous navigation.
• To all U.S. vessels on the high seas not subject to another nation’s geographic jurisdiction.
Although the International Rules state that they are applicable “Upon the high seas and in all waters connected therewith navigable by seagoing vessels” [1(a)], there is a provision for a nation to prescribe its own rules for harbors, rivers, and inland waterways [1(b)]; this is the basis for the U.S. Inland Rules.
Manner of Presentation
The 1980 U.S. Inland Navigation Rules were derived from the 1972 International Rules, and nearly match them rule for rule, and annex for annex, in format. Considerable effort was taken to make the language identical wherever possible. Where there are differences, they exist because different operating conditions on the inland waters of the United States require rules for safety of navigation different from those applicable on the high seas. On inland waters, vessels are generally smaller in size and the distances are less. The International Rules, of course, do not contain the several special provisions for the Great Lakes or Western Rivers.
Thus, the consideration of the International Rules for lights and day shapes can be limited to the relatively few points of difference. Where a difference is not noted, the International and 1980 U.S. Inland Rules are identical, except for minor editorial modifications of no significance to vessel operation.
Navigation Lights
The requirement for showing navigation lights and day shapes is the same for waters governed by the International Rules as for those where the U.S. Inland Rules apply.
Definitions
The International Rules definitions do not include a “special flashing light”—the yellow light used at the bow of barges pushed ahead on inland waters.
The International Rules do include a definition not used in the Inland Rules. A “vessel constrained by her draft” is considered a power-driven vessel that, because of her draft in relation to depth and width of navigable water, is severely restricted in her ability to maneuver.
Lights for Power-Driven Vessels Underway
Small craft with sidelights flush-mounted in the hull below the rub rail do not comply with the International Rules requirement that such lights be above the “uppermost continuous deck.”
Lights for Vessels Anchored or Aground
The International Rules contain no provision for special anchorage areas as established in inland waters. The only exception to the requirement for an anchor light is for vessels under 7 meters (23.0 ft) in length anchored in areas free of water-borne traffic. Vessels under 12 meters (39.4 ft) in length are exempt from the requirements to show special lights and day shapes when aground.
Figure 4-18 A power-driven vessel less than 12 meters (39.4 ft) in length may have an all-round white light in lieu of the masthead and stern lights under both Inland and International Rules.
Lights for Vessels Towing
A vessel pushing a tow ahead or towing alongside must show a normal white stern light (rather than two yellow towing lights in a vertical line, as required by Inland Rules). [24(c)] A vessel pushed ahead or towing alongside will not carry the special flashing yellow light used at the bow of such barges on inland waters.
Lights for Vessels Constrained by Draft
International Rule 28 permits a vessel that is “constrained by her draft” to show three red all-round lights in a vertical line wherever they can best be seen; see Figure 4-19. (This is the rule that is omitted from the U.S. Inland Rules.)
Figure 4-19 Only the International Navigation Rules recognize a vessel “constrained by her draft”; this category does not appear in the Inland Rules. At night, such a vessel shows three all-round red lights arranged in a vertical line; by day, it exhibits a cylindrical shape.
Day Shapes of the International Rules
International Rule 25(e) requires the use of a cone, with point downward, as a day shape on all sailing vessels using machinery for propulsion while its sails are up. There are no exceptions in this rule for smaller sailboats.
The exception for showing an “anchor ball” is limited to vessels under 7 meters (23.0 ft) in length, when anchored in waters not subject to waterborne traffic. A similar exception for vessels under 12 meters (39.4 ft) applies to the requirements for showing three balls in a vertical line if aground. [30(e) and (f)]
International Rule 28 permits a vessel “constrained by her draft” to show a day shape consisting of a cylinder. The cylinder must be not less than 0.6 meter (2.0 ft) in diameter with height twice the diameter.
GENERAL CAUTIONS
Although they are not strictly a part of the Inland or International Rules or their annexes, several other navigation light matters should be considered by every skipper.
Interpreting What You See
All that has gone before in this chapter has related to what lights are placed where on various vessels. If you have learned this, great—but that is only the beginning! You must also learn how to interpret the navigation lights that you see when you are underway at night—and for your safety, learn it well.
If you see a red navigation light on the other vessel, you immediately know that it is the stand-on vessel and you must yield—that’s why it is red.
If you see two or three white vertical lights, that could be a tug with a tow astern. Look for the lights on the towed vessel, and don’t try to pass between the tug and its tow.
And there are other lights and combinations of lights that you must be able to instantly recognize—the lights for a sailboat that is privileged over a motorboat, the special lights of various fishing vessels, a dredge, or a vessel not under command. Study the requirements for navigation lights from the viewpoint of a “looker” as well as a boat owner.
Certification of Navigation Lights
The U.S. Coast Guard now requires boat manufacturers to install on boats that they build only navigation lights that have been certified as meeting the requirements of the Navigation Rules with respect to color, arc of coverage, and intensity. They must also be installed so that they meet requirements of those rules when in use.
Craft constructed prior to November 2003 may or may not (all too often “not”) meet the specifications contained in the Rules and their annexes. Even lights that do meet the design requirements are often installed improperly. The most frequent discrepancy is a sidelight that can be seen across the bow, sometimes by as much as 30 or more degrees. Such improper lights, usually on smaller boats, make it difficult or impossible at night to determine the heading of that craft. Another frequent problem is an all-round white light at the stern that is too low, so its light is blocked by persons on board, a canvas top, or other structural part of the boat, and it cannot be seen by another craft traveling in the opposite direction.
Misuse of Navigation Lights
Boats are often seen underway at night showing both running lights and the anchor light. This presents a confusing picture to another boat approaching from astern of the first vessel—two white lights such as would be seen from ahead of a larger vessel under the Inland Rules. This illegal situation is usually caused by carelessness on the part of the skipper—he turned on one too many switches! Check your lights each time you turn them on.
Another problem is the Class A (less than 16 feet) or 1 (16 to 26 feet) boat at anchor that shows its combination red-and-green light as well as its all-round white light aft. Here the illegal situation is caused by the manufacturer who installed only one switch for all navigation lights—making it impossible for the boat to show only the white light as an anchor light without also showing the red-and-green sidelights. The solution is for the skipper to install a second switch or a single switch with two separate “on” settings so that the colored and white lights may be controlled independently.
Maintenance of Navigation Lights
Lights should always be checked before leaving dock if night operation is scheduled. Many boats are used only in the daytime, but the wise skipper checks all navigation lights once a month—whether they have been used or not. One or more spare bulbs and fuses, each of the proper type and size, should always be on board.
It is common for the color of plastic sidelight lenses to begin to fade after a few years of service. Red lenses tend be affected most noticeably, often to the point where the light through a faded lens appears almost white. It is the owner/operator’s responsibility to replace faded lenses to ensure that the sidelights show their proper colors.