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TABLE D.-(Continued.)-SAILING VESSELS
TABLE OF RESERVE BUOYANCY AND FREEBOARD FOR FIRST-CLASS SEA-GOING IRON AND STEEL SAILING VESSELS AND COMPOSITE AND WOOD VESSELS OF THE HIGHEST CLASS. (In Salt Water.)
Correction in inches for a change of 10 ft. in the length.
An additional freeboard of three inches is required for the North Atlantic trade, and is to apply to all vessels sailing to, or from, the Mediterranean, or any British or European port, and which may sail to, or from, or call at ports in British North America, or east rn ports in the United States, north of Cape Hatteras, from October to March, inclusive
TABLE D.-SAILING VESSELS.
TABLE OF RESERVE BUOYANCY AND FREEBOARD FOR FIRST-CLASS Sea-GoinG
Percentage Reserve Buoyancy. (Iron Vessels.)
Moulded depth and length.
Correction in inches for
a change of 10 ft. in the length..
ft. ft. ft.
ft. in. ft. in. ft. in. ft. in. ft. in. ft. in. ft. in. ft. in. 23 6 24 0 24 625 O 25 6 26 0 26 6 27 O
ft. in. ft.
ft. ft. 250 255
A. Correction in inches for a change of 10 ft. in the length.
10 5 11
TABLE D.-(Continued.)-SAILING VESSELS. TABLE OF RESERVE BUOYANCY AND FFEEBOARD FOR FIRST-CLASS SEA-GOING IRON AND STEEL SAILING VESSELS. (In Salt Water.) Percentage Reserve Buoyancy.
ft. ft. ft. 285 290 295
ft. in. ft. in. ft. in. ft. in. ft. in. ft.
30′9 | 31°2 | 31′4 | 317 | 320 32'3
Moulded Depth and Length.
in. ft. in
in. ft. in. ft. in. ft. in. ft. in. ft. in. ft. in.
300 305 310
in. ft. in. ft.
7 of 7 3 7 5 7 I 7 4 7 6
7 5 7 7
7 5 7 ९
7 ५. 7 10
An additional freeboard of three inches is required for the North Atlantic trade, and is to apply to all vessels sailing to, or from, the Mediteranean, or any British or European port, and which may sail to, or from, or call at ports in British North America, or eastern ports in the United States, north of Cape Hatteras, from October to March, inclusive
Explanatory Notes on the Application of the Tables of Freeboard, drawn up with a view to securing Uniformity of Practice on the part of those entrusted with the Assignment of Freeboard under the Load Line Act of 1890, and amended December, 1898.
Deck Line.-In the case of vessels with uncovered iron or steel decks, a width of gutter waterway is to be assumed, and the point so obtained levelled out to the vessel's side. In the case of vessels of 24 ft. beam and under, the width of the waterway assumed should be 12 in., and in vessels of 42 ft. and above, 21 in. In vessels of between 24 and 42 ft. beam the width of the gutter waterway is to be taken as half an inch for every foot in beam.
Where a wood deck maintains a uniform thickness to the sides of a vessel, the same method should be adopted.
In cases where an iron deck is partly covered with wood, the deck-line is to correspond with the top of the deck amidships, whether the deck at that part be of wood or of iron, and the necessary corrections should be made in accordance with sub-paragraph (4), page 68, as also the correction always required to the statutory deck-line.
Bridge-houses in Spar-decked Ships.-In a spar-decked ship, where an efficient bridge-house is fitted amidships, covering the engine and boiler openings, if it extends over at least two-fifths of the vessel's length and has scantlings equal to the requirements of Lloyd's Register for bridge-bouses, it is to be taken into consideration in estimating the strength of the vessel for freeboard.
The allowance on this account should not in any case exceed that given in the following table :
90 A Additions 80 A
Moulded Depth of Vessel
Tables of Freeboard.-Additional freeboard will be required in the case of vessels classed 90 A and 80 A, or in vessels of equivalent strength thereto in accordance with the following scale :— Length of vessel
225. 250. 275. 300. Inch. Inches. Inches. Inches. Inches. Inches. 14
Wherever in these explanatory notes reference is made to classes of vessels of Lloyd's various types, it is to be understood that these apply equally to all other vessels of equivalent strength, whether
classed by other classifying associations, such, for instance, as the Bureau Veritas or the British Corporation, or unclassed.
Para. 1. Length.-The length of erections is to be measured with reference to the length of the vessel on the load-line, i.e., any portion of the erections forward of the fore side of the stem on the load-line, or abaft the after side of the after post on the load-line, is not to be measured for deductions.
Para. 3. Depth of Hold.—The depth of hold as used in the computation for ascertaining the coefficient of fineness in iron and steel sailing vessels is to be measured to the top of the ceiling, and in steam vessels to the top of the floors.
Para. 4. Coefficient of Fineness.-No alteration is to be made in the freeboard in consequence of the coefficient of fineness being either smaller or greater than those given on the page of the tables from which the ship's freeboard is taken.
Para. 5. Moulded Depth.-In cases where a wood deck of extra thickness is fitted, or where a wood deck is doubled throughout, the moulded depth should be increased by the excess of thickness. The freeboard should then be set off from the top of the deck of increased thickness at the side of the vessel.
Para. 6. Freeboard.-In case of the freeboard being ascertained by an actual calculation of the reserve buoyancy, the drawing used in such calculation should be verified by actual measurements at the ship, and such drawing and calculations forwarded to the Board of Trade, and whatever the result of the calculation the freeboard assigned should not be less than would be obtained by taking from the tables the freeboard corresponding to the smallest coefficient for a vessel of the same moulded depth, except in sailing vessels with large rise of floor. (See page 76.)
Freeboard as ascertained by these tables is to be measured to the intersection of the deck with the side of the vessel, but in granting certificates of freeboard this must always be corrected so as to state the freeboard amidships when measured to the deck-line, marked in accordance with the statute.
Sub-paras. (a) and (b).—For vessels having iron upper-decks not covered with wood, the allowance is to be made under sub-para. (a), when the erections extend over less than ths of the length; but in all vessels when the erections cover ths or more of the length, and in spar and awning-decked vessels the allowance is to be made under sub-para. (b).
Sul-para. (b)(6)-In spar-decked vessels having iron spar decks, and in awning-decked vessels having iron main decks, the freeboard by the tables should be calculated as if those decks were wood covered, i.e., the ordinary thickness of a wood deck, less the thickness of the stringer plate, should be deducted from the freeboard, also in vessels where ths or more of the main deck is covered by substantial enclosed erections, the freeboard found from the tables should be measured amidships from a wood deck, or, if the deck is of iron, it should be measured from the iron deck, and the ordinary thickness of a wood deck required for that size of ship, less the thickness of the stringer plate, should in that case be deducted from the freeboard. In vessels which have ths of the
deck covered, ths the thickness of a wood deck, less the thickness of the stringer plate is to be deducted from the freeboard. Between ths and ths a proportionate quantity; for example, for ths covered allow ths the thickness of the deck, after deducting the thickness of the stringer plate. The remainder of the paragraph should be read as printed. N. B.-When the deductions referred to in this sub-para. (6) are allowed, the moulded depth is not to be reduced as per sub-para. (a), para. 6.
Para. 9. If the erections are at all under ths of the vessel's length, the entire correction for length as given in the tables is to be applied.
Para. 11.-This paragraph does not apply to vessels where the erections cover less than ths of the length, except in cases where the after erection covers at least ths of the length, and the total length covered is between ths and ths the length of the vessel. In such cases the allowance should be proportioned between that allowed for erections ths the length under para. 14 and that allowed for erections covering ths of the length under para. 11, and the corrections for length and sheer should be included in estimating this allowance. In all other cases of vessels with erections covering less than ths of the length, para. 14 is to be used.
No allowance is to be made for a monkey forecastle which is less in height than the main or top-gallant rail; where this condition is satisfied, the length to be used in estimating the allowance is to be obtained by multiplying the length of the monkey forecastle by its height and dividing by 6 ft., the minimum height of a topgallant forecastle. This rule applies to vessels coming under paras. 12, 13, and 14, as well as under para. 11. In case of vessels having no forecastle, but in other respects coming under this para., the allowance for erections should be estimated on the supposition that there is a forecastle th the length of the vessel, deducting from this twice the allowance which the vessel would have for such a forecastle under para. 15.
In strong well-decked vessels of the modern type, having erections covering at least ths of the length of the ship, the bridge-house alone covering at least ths of the length, the maximum allowance for extra strengthening are as follows:
Vessels with plating number under 18,000, 24 inches.
The extra strength is to be as given in section 44, Lloyd's Rules for 1889 for iron and steel vessels. The freeboards assigned to these vessels must never be less than would be assigned for a complete awning-decked vessel of the same dimensions. The allowance prescribed below for well-decked vessels with strength. ened bridge bulkheads is not to be given in addition to the allowance under this clause.
In part awning-deck vessels with raised quarter-decks and long superstructures strengthened as required for the strong well-decked vessel referred to above, and where the break of the quarter-deck is th the vessel's length abaft amidships, a reduction may be made