Maritime History of the Great Lakes

Marine Review (Cleveland, OH), June 1921, p. 273

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June, 1921 pacity for British shipping of 1,000,000 tons. The freeboard tables, with the exception of the spar deck table, were modified, and the amendments indicated clearly the considerable reductions made in the freeboards of awning deck vessels, the fairing up of the flush deck freeboard curve from 28 feet to 42 feet molded, and the reduc- tions made to the freeboards of the larger sized sailing ships. The increased drafts allowed by the new awning deck table necessi- tated a higher standard of strength for this type, and the old standard, i. e, Lioyd's 1885 awning deck rules was augmented by the addition of heavier topside scantlings. tion to the table alterations the al- lowances for erections were modified and consideration given also to the freeboard of vessels with scuppers and other openings in the side, and it was decided maximum reductions under the revised regulations should be granted only where means of clos- ing all such openings tory, the machinery castings above the uper deck were of sufficient height and strength, and the, hatchways, hatch covers, etc., were efficient and in good condition. When these _ conditions were not complied with, the freeboards were to be increased, due regard be- ing given to the vessel's trade. British Make In 1908, with a view to bringing the German freeboard tables into line Revision with the revised British requirements, modifications were made to the erec- tion allowances, and more detailed in- formation was given for dealing with the freeboards of special types, such as shelter deck vessels with tonnage openings. The provisions contained in the British 1906 rules with regard to the protection of openings, nature of appliances required for closing op- enings in erection bulkheads, height and strength of machinery castings and cargo hatches and the requirements as to ports, scuppers, etc. were all included in the 1908 rules. The Brit- ish practice of adding to the free- boards of vessels engaged in the win- ter 'north Atlantic trade was adopted, and the special consideration previous- ly given to wood cargo vessels and small coasting sailers was canceled. The flush deck and awning deck ta- bles were both extended and increases were made to the table freeboards in the case of the larger sized sailers. The latest British load line com- - mittee was appointetd in 1913 to ad- vise the board of trade on the atti- tude to be adopted by the British representatives at a forthcoming in- ternational conference on load lines, In addie- were satisfac-' MARINE REVIEW and also to investigate and report as to whether the 1906 revised tables required further revision in the light of experience. Owing to the out- break of the war, however, this con- ference was never called, and for the Same reason the issue of the commit- tee's report was delayed until the end of 1915. The decisions given by courts of inquiry into the loss in 1912 of two vessels, whose freeboards had been reduced in 1906, caused consid- erable comment and_ probably had something to do with the terms of reference. In one case the court had found that primary cause of the loss of the ship and lives was her insuffi- cient freeboard, -and in. the | other, while the loss of the ship was not attributed to lack of freeboard,' the opinion was expressed that the free- board granted under the revised regu- lations was dangerously small. In investigating effects of the 1916 revision of the freeboard 'tables, every consideration was given to the record of shipping casualties and to the ex- perience of shipowners and masters as to the behavior of their vessels since they were marked with the new load lines, the classification societies being also consulted as to the prac- tical working of the revised freeboards over a period of seven years and their effect upon the number and nature of actual damages sustained to classed vessels. The load line committee, af- ter reviewing the evidence in the two courts of inquiry mentioned above, decided that insufficient freeboard had nothing to do with the loss of either vessel and came to the conclusion that there was no foundation in fact for the allegation that the 1906 revi- sion of the freeboard tables had caused a considerable increase in the number of losses of vessels. The opinion was expressed, however, that although the freeboards allowed by the revised ta- bles were quite sufficient to insure the safety of vessels, the reduction in freeboard in some cases had had the effect of making the ships less com- fortable, owing to the greater lia- bility for water to come on board the weather decks. : Draft Universal Rules The subcommittee appointed to deal with the highly technical questions involved in freeboard, having decided the present British regu'ations. were not adapted for an international stand- ard, proceeded with their investigations with a view to evolving new free- Board rules and regulations suitable for submission to an international con- ference. The existing British rules, owing to the many additions, modifi- cations and amendments made since the first issue in LCL, with 1885, had become 273 complicated and somewhat difficult to apply and did not treat the different types of vessels in an equitable man- Every endeavor was made in drawing up the new freeboard regu- lations to make the rules simple and easy of application, and the result of the committee's labors is embodied in their proposed rules for 'the assign-_ ment of load lines to merchant vessels, which are undoubtedly a considerable improvement over the present regula- tions. No Allowance for Excess of Sheer There are now two distinct sheer standards, parabolic curves where the sheer forward is twice the sheer aft, one for vessels with forecastles and a higher standard for flush deck ves- sels. -Although all types of vessels are penalized for deficiency of sheer as compared with the standard, it is not proposed to grant any allowance for excess of sheer over the standard. Block coefficients at 85 per cent of the molded depth are used with the tables instead of coefficients of fineness derived from under deck tonnage. The depth to be used with the tables is taken to the top of the deck at side, whether of wood or steel, and sum- mer freeboards are tabulated as in the German regulations. The committee recommended that the freeboards of British ships be marked from the deck at side instead of being set down from a statutory deck line in accordance the merchant shipping acts. A more logical method of assessing the value of erections which takes ac- count of their extent, disposition, and the nature of the closing appliances, has been adopted. The committee lays particular stress upon the necessity of providing adequate protection for open- ings, and instead of proposing to make additions to the freeboards of vessels on account of deficiencies in this re- spect, "Conditions of Assignment of Freeboard" are laid down with re- gard to the strength of machinery casings, hatches, ventilators, openings in the superstructures and in the sides, such as gangways, doors, side ports, © etc., which are an amplification of the present requirements. Probably the most important part of the committee's work was the formu- lating of a new standard of strength to be used in association with the new freeboard rules. <A technical staff was employed to carry out the neces- sary research work, and under the guidance of Professor Abell, of Liver- pool university, 'now chief surveyor of Lloyd's, a very thorough analysis was made of ship structural practice as determined from the 1913 rules of Lloyd's, British Corp., Bureau Veritas and Germanischer Lloyd's, as it was

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