160.035-9—Cubic capacity of lifeboats.

(a) Definitions. The following definitions apply to the measurement of a lifeboat to determine its cubic capacity.
(1) Length (L ). The length is the distance in feet from the inside of the plating or planking at the stem to the corresponding position at the stern. In the case of a boat with a square stern, the after terminus is the inside of the transom.
(2) Breadth (B ). The breadth is the distance in feet over the plating or planking at the point where the breadth of the boat is greatest.
(3) Depth (D ). The depth is the distance in feet amidships inside the plating from the top of the keel to the level of the gunwale. The depth used for calculating purposes shall not exceed 45 percent of the breadth.
(4) Sheer. Lifeboats shall have a sheer at each end at least equal to 4 percent of the length, and a sheer at the quarter points of at least 1 percent of the length. If less sheer is provided, the depth used to determine the cubic capacity shall be assumed to be reduced so as to achieve this minimum sheer.
(b) Formula. The cubic capacity shall be determined by the following formula:
L × B × D × 0.64
In the case of lifeboats with unusual proportions, the Commandant may require that the cubic capacity be calculated by exact measurements from which the exact seating capacity may be determined.
(c) Motor-propelled lifeboat. The cubic capacity of a motor-propelled lifeboat shall be determined in the same manner as an oar-propelled lifeboat and then deducting from the gross volume, a volume equal to the engine box and accessories, and when carried, the radio cabin, searchlight, and their accessories. The volume of such equipment extending above the sheer line need not be deducted.
[CGFR 65-9, 30 FR 11467, Sept. 8, 1965, as amended by CGD 95-028, 62 FR 51213, Sept. 30, 1997]