Handbook of the Nautical Rules of the Road by Llana & Wisneskey

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Rule 24 -- Towing and Pushing


Rule 24 tells us which navigation lights towing vessels must display as well as those the towed vessel (or object) must display. Some of the Inland provisions are the same as the International in this Rule, but others, particularly for pushing ahead or towing alongside, are different. The first four paragraphs, (a) through (d), apply to towing vessels, while paragraphs (e) through (h) apply to towed vessels. Paragraph (i), found only in the Inland Rules, exempts Western Rivers towboats from the general requirements.


INTERNATIONAL

INLAND

(a) A power-driven vessel when towing shall exhibit:

(i) instead of the light prescribed in Rule 23 (a)(i) or (a)(ii), two masthead lights in a vertical line. When the length of the tow, measuring from the stern of the towing vessel to the after end of the tow exceeds 200 meters, three such lights in a vertical line;

(ii) sidelights;

(iii) a sternlight;

(iv) a towing light in a vertical line above the sternlight;

(v) when the length of the tow exceeds 200 meters, a diamond shape where it can best be seen.

(a) A power-driven vessel when towing astern shall exhibit:

(i) instead of the light prescribed in Rule 23 (a)(i) or (a)(ii), two masthead lights in a vertical line. When the length of the tow, measuring from the stern of the towing vessel to the after end of the tow exceeds 200 meters, three such lights in a vertical line;

(ii) sidelights;

(iii) a sternlight;

(iv) a towing light in a vertical line above the sternlight; and

(v) when the length of the tow exceeds 200 meters, a diamond shape where it can best be seen.

 

Paragraph (a) presents the lighting requirements for vessels towing astern. Although the International version says "when towing" and does not employ the explicit Inland language "when towing astern," the International requirement nevertheless applies only to vessels towing astern.

Subparagraph (i) needs special comment. Here the length of the vessel and tow determines the arrangement of masthead lights. Vessels less than 50 meters in length (those that have to display only one masthead light when underway without a tow) are required to display two masthead lights in a vertical line or, if the tow length is over 200 meters, three in a vertical line.

Vessels over fifty meters when underway without a tow must display both a forward and, mounted higher, an after masthead light. The masthead lights, forward and aft, thus act as a range, giving others an idea of the vessel's orientation or relative course.

When underway with a tow, these larger vessels are required to replace either (not both) the forward or the after masthead light with a vertical array of of either two or three masthead lights, depending on the length of the tow. A vessel over 50 meters long with a tow less than two hundred meters long must display two masthead lights on its forward mast and one on its after mast. Alternatively, it could display two two lights on its after mast and one on its forward mast. Such a vessel would also of course display the requisite sidelights, a sternlight, and yellow towing light.


INTERNATIONAL

INLAND

(b) When a pushing vessel and a vessel being pushed ahead are rigidly connected in a composite unit they shall be regarded as a power-driven vessel and exhibit the lights prescribed in Rule 23.

(b) When a pushing vessel and a vessel being pushed ahead are rigidly connected in a composite unit they shall be regarded as a power-driven vessel and exhibit the lights prescribed in Rule 23.

 

Paragraph (b) of Rule 24 is less of a requirement than a statement that certain specialized tug-barge combinations do not fall under Rule 24 but rather under the rules governing lighting of ordinary power-driven vessels. This provision applies only to pushing ahead.

Described as being "rigidly connected in a composite unit," these vessels are usually designed so that the pushing vessel's bow fits in a matching notch in the stern of the "barge." A locking device holds them so rigidly together that little or no independent motion is permitted. These rigid tug-barge combinations do not need to be certified or classified in order to display the navigation lights of a power-driven vessel. (See also the interpretative rules in Title 33, Code of Federal Regulations, section 82.3/International, and section 90.3/Inland.)


INTERNATIONAL

INLAND

(c) A power-driven vessel when pushing ahead or towing alongside, except in the case of a composite unit, shall exhibit:

(i) instead of the light prescribed in Rule 23 (a)(i) or (a)(ii), two masthead lights in a vertical line;

(ii) sidelights;

(iii) a sternlight.

(c) A power-driven vessel when pushing ahead or towing alongside, except as required by paragraphs (b) and (i) of this Rule, shall exhibit:

(i) instead of the light prescribed either in Rule 23 (a)(i) or 23 (a)(ii), two masthead lights in a vertical line;

(ii) sidelights; and

(iii) two towing lights in a vertical line.

 

Paragraph (c) specifies the lights for vessels pushing ahead or towing alongside. Significant differences exist between the International and Inland versions. Both require sidelights. Both require two masthead lights carried in a vertical line. But the Inland Rule exempts, in paragraph (i), towboats on Western Rivers from having to display masthead lights. In lieu of the sternlight required by the International version, two yellow towing lights are required by the Inland Rules.


INTERNATIONAL

INLAND

(d) A power-driven vessel to which paragraphs (a) or (c) of this Rule apply shall also comply with Rule 23 (a)(ii).

(d) A power-driven vessel to which paragraphs (a) or (c) of this Rule apply shall also comply with Rule 23 (a)(i) and 23 (a)(ii).

 

The wording in paragraphs (a) and (c) did not make clear the requirement for larger towing vessels to display both forward and after masthead lights, so paragraph (d) was added. Yet its inclusion seems only to have made the requirement more confusing. Paragraph (d) is aimed at vessels over fifty meters in length and says if you elect to display your two or three masthead lights (in a vertical line) for towing on the forward mast, then you must also display another masthead light on the after mast. If the two or three masthead light towing array is mounted on the after mast, a single masthead light must be displayed on the forward mast. Whether to display the vertical array masthead lights on the forward mast or on the after mast is the decision of the builder and operator.

Because towing vessels under 50 meters need carry masthead lights on only one mast, they can ignore paragraph (d), although they may voluntarily carry both forward and after masthead lights.


INTERNATIONAL

INLAND

(e) A vessel or object being towed, other than those mentioned in paragraph (g) of this Rule, shall exhibit:

(i) sidelights;

(ii) a sternlight;

(iii) when the length of the tow exceeds 200 meters, a diamond shape where it can best be seen.

(e) A vessel or object other than those referred to in paragraph (g) of this Rule being towed shall exhibit:

(i) sidelights;

(ii) a sternlight; and

(iii) when the length of the tow exceeds 200 meters, a diamond shape where it can best be seen.

 

Paragraph (e) of both the International and Inland Rules begins the lighting requirements for vessels being towed, stipulating that vessels being towed astern have sidelights and a sternlight. The intensity of the lights is based on the length of the towed vessel, excluding towline and towing vessel.

Annex I to the Inland Rules contains a special provision affecting the intensity of battery-powered navigation lights on unmanned barges. A diamond shape is displayed by day when the length of the tow, including towed vessel and towing line, exceeds 200 meters.


INTERNATIONAL

INLAND

(f) Provided that any number of vessels being towed alongside or pushed in a group shall be lighted as one vessel,

(i) a vessel being pushed ahead, not being part of a composite unit, shall exhibit at the forward end, sidelights;

(ii) a vessel being towed alongside shall exhibit a sternlight and at the forward end, sidelights.

(f) Provided that any number of vessels being towed alongside or pushed in a group shall be lighted as one vessel:

(i) a vessel being pushed ahead, not being part of a composite unit, shall exhibit at the forward end, sidelights, and a special flashing light; and

(ii) a vessel being towed alongside shall exhibit a sternlight and at the forward end sidelights.

 

Paragraph (f) specifies the navigation lights for vessels being pushed ahead or towed alongside. If several barges are tied together and towed as a unit, then they must be lighted as though a single vessel. The light must be intense enough to meet the requirement for the length of the group, not the length of a single barge within the group (see Rule 22).

Vessels being towed alongside have the same requirement under both International and Inland Rules: sidelights and a sternlight.

Vessels being pushed ahead carry sidelights, as required by both sets of Rules, but the Inland Rules also demand a special flashing light at the front of the tow. Inland Rule 21 (g) describes this flashing yellow light, whose display is not allowed on vessels being towed alongside.


INTERNATIONAL

INLAND

(g) An inconspicuous, partly submerged vessel or object, or combination of such vessels or objects being towed, shall exhibit:

(i) if it is less than 25 meters in breadth, one all-round white light at or near the forward end and one at or near the after end except that dracones need not exhibit a light at or near the forward end;

(ii) if it is 25 meters or more in breadth, two additional all-round white lights at or near the extremities of its breadth;

(iii) if it exceeds 100 meters in length, additional all-round white lights between the lights prescribed in subparagraphs (i) and (ii) so that the distance between the lights shall not exceed 100 meters;

(iv) a diamond shape at or near the aftermost extremity of the last vessel or object being towed and if the length of the tow exceeds 200 meters and additional diamond shape where it can best be seen and located as far forward as is practicable.

(g) An inconspicuous, partly submerged vessel or object being towed shall exhibit:

(i) if it is less than 25 meters in breadth, one all-round white light at or near each end;

(ii) if it is 25 meters or more in breadth, four all-round white lights to mark its length and breadth;

(iii) if it exceeds 100 meters in length, additional all-round white lights between the lights prescribed in subparagraphs (i) and (ii) so that the distance between the lights shall not exceed 100 meters; Provided, That any vessels or objects being towed alongside each other shall be lighted as one vessel or object;

(iv) a diamond shape at or near the aftermost extremity of the last vessel or object being towed; and

(v) the towing vessel may direct a searchlight in the direction of the tow to indicate its presence to an approaching vessel.

 

Paragraph (g) provides for lighting "inconspicuous, partly submerged" vessels or objects that, by their every nature, cannot be provided with conventional sidelights and sternlights. This "vessel" class includes dracones, which are large flexible bags used for transporting liquids.

The International and Inland versions differ in language and detail. Both require an all-round white light at each end of the towed vessel, although the International version exempts dracones from the forward light stipulation. Both require two additional white lights to mark the beam on wide (twenty-five meters or more) tows. For long tows, subparagraph (g)(iii) provides for extra lights so that there will not be an unlighted span of more than 100 meters. These intermediate lights on long tows should be mounted singly if the tow is less than 25 meters wide or in pairs for wider tows.

The Inland subparagraph (g)(iii) says sthat when several vessels are being towed alongside one another, the extra intermediate lights for very long tows shall be displayed as though the several vessels were one.

The International version does not contain a similar caveat because all of the International paragraph (g) requirements are applied to combinations of inconspicuous, partly submerged vessels or objects as if they were one. In the Inland version, however, only the (g)(iii) requirement applies to combinations.

By day both the International and Inland Rules demand a diamond shape at the "aftermost extremity" of the tow. For tows exceeding two hundred meters in length (including towline) the International Rules (but not the Inland) require an additional diamond shape displayed on the towed vessel or object "where it can best be seen and located as far forward as is practicable."

The Inland paragraph (g) includes a statement permitting but not mandating the use of a searchlight aimed toward the tow for the benefit of an approaching vessel. Although the International version of paragraph (g) does not explicitly state that such a searchlight is permitted, its use for the purpose of illuminating a tow would be allowed under International Rules 2 and 36.


INTERNATIONAL

INLAND

(h) Where from any sufficient cause it is impracticable for a vessel or object being towed to exhibit the lights or shapes prescribed in paragraph (e) or (g) of this Rule, all possible measures shall be taken to light the vessel or object towed or at least to indicate the presence of such vessel or object.

(h) Where from any sufficient cause it is impracticable for a vessel or object being towed to exhibit the lights or shapes prescribed in paragraph (e) or (g) of this Rule, all possible measures shall be taken to light the vessel or object towed or at least to indicate the presence of the unlighted vessel or object.

 

In some situations a vessel being towed astern cannot be fitted with proper navigation lights. For example, a vessel disabled by storm or accident may be without power and the urgency or rescue efforts may prevent the fitting of emergency lighting. In such a case, paragraph (h) excuses compliance with conventional lighting requirements but says every effort must be made to indicate to other vessels in the area that a vessel (or object) is being towed. Searchlights, the towed vessel's deck lighting, illumination flares, radar, radiotelephone, or whatever else is available should be used.


INLAND

(i) Notwithstanding paragraph (c), on the Western Rivers (except below the Huey P. Long Bridge on the Mississippi River) and on waters specified by the Secretary, a power-driven vessel when pushing ahead or towing alongside, except as paragraph (b) applies, shall exhibit:

(i) sidelights; and

(ii) two towing lights in a vertical line.

 

Towing vessels pushing barges ahead need not display masthead lights when on certain inland waters, including the Western Rivers above the Huey P. Long Bridge, the Tennessee-Tombigbee Waterway, Tombigbee River, Black Warrior River, Alabama River, Coosa River, Mobile River above the Cochrane Bridge at St. Louis Point, Flint River, Chattachoochee River, and the Apalachicola River above its confluence with the Jackson River (see section 89.27, Title 33 of the Code of Federal Regulations for a listing of waters on which Inland Rule 24 (i) applies.)

This Inland Rule provision was added not because the absence of masthead lights contributed to safety but rather because their height made passing under low bridges more difficult. If towing vessels operating on these waters wish to have the higher visibility that masthead lights afford, they may display masthead lights according to the paragraph (c) general requirements for inland waters. The display of masthead lights on Western Rivers while pushing ahead should not cause confusion because such display is permitted (and required) in the case of towboats complying with the International Rules and operating on Western Rivers, and their display is required for all towing vessels on Western Rivers below the Huey P. Long Bridge.


INTERNATIONAL

INLAND

(i) Where from any sufficient cause it is impracticable for a vessel not normally engaged in towing operations to display the lights prescribed in paragraph (a) or (c) of this Rule, such vessel shall not be required to exhibit those lights when engaged in towing another vessel in distress or otherwise in need of assistance. All possible measures shall be taken to indicate the nature of the relationship between the towing vessel and the vessel being towed as authorized by Rule 36, in particular by illuminating the towline.

(j) Where from any sufficient cause it is impracticable for a vessel not normally engaged in towing operations to display the lights prescribed by paragraph (a), (c) or (i) of this Rule, such vessel shall not be required to exhibit those lights when engaged in towing another vessel in distress or otherwise in need of assistance. All possible measures shall be taken to indicate the nature of the relationship between the towing vessel and the vessel being assisted. The searchlight authorized by Rule 36 may be used to illuminate the tow.

 

The final provision in Rule 24 concerns so-called good Samaritan towing. International paragraph (i) and Inland paragraph (j), which are essentially the same, permit a vessel to tow another without displaying the navigation lights of a towing vessel. The towing vessel must not have expected to become involved in towing, having only fortuitously encountered another vessel "in distress or otherwise in need of assistance." Good Samaritans must indicate to others, by whatever means available, that they are engaged in towing.

Obviously, commercial towing operations do not qualify under this provision. Nor do vessels whose normal activities include the towing (or expectation of towing) of disabled vessels, regardless of whether a fee is collected.

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