Friday, April 10, 2009

Power Driven Vessels Underway (Rule 23)

Rule 23: This Rule establishes what might be termed the basic requirements for navigation lights, sometimes called "running lights," for vessels underway. There are differences between the International and Inland Rules. The Inland Rules have more options regarding placement.

Note: The International Rules have provision for craft less than 7 meters long operating at speeds not greater than 7 knots (the vessel can be capable of greater speeds, but must not be operated at more than 7 knots while using this Rule). This provision does not appear in the Inland Rules. The Inland Rules contain a special provision for vessels on the Great Lakes that does not appear in the International Rules.

No where in Rule 23 does the term "range lights" appear, but the two masthead lights, where fitted on larger vessels, do form a range similar to that established by two aids to navigation. This "range" helps in determining the orientation of a ship seen at a distance at night, the white masthead lights can be seen at a greater distance than the red and green sidelights.
In October, 1996, Inland Rule 23(a)(i) was changed. The revised Rule eliminates the exception for vessels less than 20 meters in length, these craft must now have their masthead light located in the forward half of the vessel. The Rule is now comparable with the corresponding International Rule.

A power-driven vessel underway shall exhibit:
a masthead light forward.
a second masthead light abaft of and higher than the forward one, except that a vessel of less than 50 meters in length shall not be obliged to exhibit such a light but may do so.
sidelights and a stern light.

An air-cushion vessel when operating in nondisplacement mode shall, in addition to the lights prescribed in this Rule, exhibit an all-round flashing yellow light, where it can best be seen.

A WIG craft only when taking off, landing and in flight near the surface shall, in addition to the lights prescribed in paragraph (a) of this Rule, exhibit a high intensity all-round flashing red light. WING-IN-GROUND CRAFT. A wing-in-ground (WIG) craft is defined as a vessel capable of operating completely above the surface of the water on a dynamic air cushion created by aerodynamic lift due to the ground effect between the vessel and the water’s surface. WIG craft are capable of operating at speeds in excess of 100 knots.
Presently, there are no Coast Guard safety standards for WIG craft. The Coast Guard has started the process of developing safety standards that will address the design, construction, operation, licensing and maintenance of WIG craft with further assistance from the Federal Aviation Administration. Additionally, the United States is working with the International Maritime Organization (IMO) to develop international standards for WIG craft.
A power-driven vessel of less than 12 meters in length may exhibit an all-round white light and sidelights.

a power-driven vessel of less than 7 meters in length whose maximum speed does not exceed 7 knots may exhibit an all-round white light and, if practicable, sidelights. The masthead light or all-round white light on a power-driven vessel of less than 12 meters in length may be displaced from the fore and aft centerline of the vessel if centerline fitting is not practicable, provided the sidelights are combined in one lantern which shall be carried on the fore and aft centerline of the vessel or located as nearly as practicable in the same fore and aft line as the masthead light or the all-round white light.
A power-driven vessel when operating on the Great Lakes may carry an all-round white light in lieu of the second masthead light and sternlight prescribed in this Rule. The light shall be carried in the position of the second masthead light and be visible at the same minimum range.