Vessel stability — metacentric height, free surface

33 CFR §155.4025

§ 155.4025 § 155.4025 Definitions. For the purposes of this subpart, the following definitions apply: means completion of a vessel's stability and structural integrity assessment through the use of a salvage software program. The data used for the calculations would include information collected by the on-scene salvage professional. The assessment is intended to allow sound decisions to be made for subsequent salvage efforts. In addition, the assessment must be consistent with the conditions set forth in 33 CFR 155.240 and 155.245, as applicable. are lines drawn following the general trend of the seaward, highwater shorelines and lines continuing the general trend of the seaward, highwater shorelines across entrances to small bays, inlets and rivers as defined in 46 CFR 7.5(c). means t…

46 CFR §185.315

§ 185.315 § 185.315 Verification of vessel compliance with applicable stability requirements. (a) After loading and prior to departure and at all other times necessary to assure the safety of the vessel, the master shall determine that the vessel complies with all applicable stability requirements in the vessel's trim and stability book, stability letter, Certificate of Inspection, and Load Line Certificate, as the case may be. The vessel may not depart until it is in compliance with these requirements. (b) In order to fulfill the requirements of paragraph (a) of this section and avoid overloading the vessel, the master must take into account the total weight of passengers, crew, and variable loads. [CGD 85-080, 61 FR 1005, Jan. 10, 1996, as amended by USCG-2007-0030, 75 FR 78092, Dec. …

46 CFR §28.501

§ 28.501 § 28.501 Substantial alterations. (a) Except as provided in paragraph (b) of this section, a vessel that is substantially altered, including the cumulative effects of all alterations, need not comply with the remainder of this subpart, provided that it has stability instructions developed by a qualified individual which comply with § 28.530 (c) through (e). (b) A vessel that is substantially altered in a manner which adversely affects its stability, including the cumulative effects of all alterations, need not comply with the remainder of this subpart, provided the stability instructions required by paragraph (a) of this section are based on loading conditions or operating restrictions, or both, which compensate for the adverse affects of the alterations. (c) The following chan…

46 CFR §28.510

§ 28.510 § 28.510 Definition of stability terms. means the entry of seawater through any opening into the hull or superstructure of an undamaged vessel due to heel, trim, or submergence of the vessel. means the static angle from the intersection of the vessel's centerline and the waterline in calm water to the first opening that cannot be closed weathertight and through which downflooding can occur. means a continuous weather deck located at the uppermost sheer line of the hull. means a vertical line corresponding to the intersection of the forward side of the vessel's stem and the vessel's waterline at the vessel's deepest operating draft. means a vessel not protected from entry of water by means of a complete deck, or by a combination of partial weather deck and superstructure which…

46 CFR §28.540

§ 28.540 § 28.540 Free surface. (a) When doing the stability calculations required by this subpart, the virtual rise in the vessel's vertical center of gravity due to liquids in tanks must be considered by calculating the following— (1) For each type of consumable liquid, the maximum free surface effect of a tank, or a transverse pair of tanks, having the greatest free surface effect, in addition to a correction for service tanks; and (2) The free surface effect of each partially filled tank and hold containing a liquid that is not a consumable or containing fish or a fish product that can shift as the vessel heels. This should include correction for any loose water within the vessel's hull associated with the processing of fish. (b) The free surface effect of tanks fitted with cross c…

46 CFR §28.545

§ 28.545 § 28.545 Intact stability when using lifting gear. (a) Each vessel which lifts a weight over the side, or that uses fishing gear that can impose an overturning moment on the vessel, such as trawls and seines, must meet the requirements of this section if that maximum heeling moment exceeds 0.67(W)(GM)(F/B), in foot-long tons (meter-metric tons), where: W = displacement of the vessel with the lifted weight or the force on the fishing gear included, in long tons (metric tons); GM = metacentric height with the lifted weight or force on the fishing gear included, in feet (meters); F = freeboard to the lowest weather deck, measured at amidships in feet (meters); and B = maximum beam, in feet (meters). (b) Except as provided in paragraph (f) of this section, each vessel must meet …