Loss of the Steamship "Titanic"

by Great Britain. Court to investigate loss of steamship "Titanic"

The surveyors, Liverpool, tested a boat 3.75 deep and having a ratio of ^D/_b = 0.41, which proved satisfactory.

Capt. Griffiths tested a boat 4.1 deep, having a ratio ^D/_b = 0.455, which he considered to be unsafe with the full complement on board.

The consensus of opinion is that the depth should not exceed 3 feet 5 inches or 3 feet 6 inches, and the ratio of D/b should not exceed 0.44. This, however, is not sufficient to guarantee sufficient seating and stability. Capt. Clarke tested a boat 24.4 × 6.55 × 2.45, which was very unsafe with the rule complement on board. The ratio D/b is only 0.38 in this case. It will be seen, however, that this craft has exceptionally fine lines and is evidently quite unsuited to carry the rule complement. It is quite evident that the form of the boat must be taken into account.

The dimensions of boats vary so greatly that generally the boat builder builds his boats "to the eye," using only a midship mold; it follows that the forms of boats of the same dimensions will vary considerably and with different workmen. Something more is required than a limitation in the ratio of depth to breadth. It is desirable that the sheer should be ample, and the form not unduly fined away within the midship half length. From consideration of the particulars and lines of the boats mentioned in the surveyor's reports, I think a simple rule to regulate the form may be devised such as I will indicate later.

It is, I think, necessary to limit the depth as a factor for ascertaining the number to be accommodated. The increase of depth beyond a certain point, while unduly increasing the number of people that may be carried, increases proportionately the required air case capacity, to meet which the seats have to be raised with a corresponding increase in the height of the center of gravity and decrease in the stability and difficulty in rowing. A boat 3.6 deep would have the thwarts about 3 feet above the bottom, and any increase in this height makes it very difficult for any ordinary man to row when sitting down. In rough sea the men would have very little control over the oars if standing up. A further objection to the very deep boat is its small stability in the light condition. It is not, I believe, an unusual occurrence for such boats to capsize in rough weather, before the passengers or crew can be got into them, and I have myself seen such a boat capsize in dock with only two men in it; due to lumpy water and a stiff breeze catching it on the beam when coming out of the shelter afforded by the dock wall.

I do not think, however, any limit of depth should be imposed, except as a measure of capacity. Any rules that may be devised should be such as are of easy and ready application, and which will not bear harshly on the boats that have already been accepted. I therefore suggest that the present rules will sufficiently meet the case, with the following modification.

In no case should the depth to be used in general rule (2) exceed 3.6 feet and 45 per cent of the breadth. In all cases where the actual depth is 45 per cent of the breadth or less, the maximum number of persons, as ascertained by rule (3) should not be allowed unless the boat has been found capable of carrying that number by actual test in the water, or unless the boat has at least 1/2 inch of sheer per foot of length, and the half-girth amidships, measured outside the plank, from the side of the keel to the top of the gunwale, is at least 90 per cent of the sum of the depth and the half breadth, and the mean of the half girths as similarly measured at one quarter the boat's length from the stem and stern post are at least 80 per cent of the sum of the midship depth and half breadth.

The thwarts and side benches should be kept as low as practicable, and the bottom boards should be so fitted that the height of the thwarts above them will not exceed 2 feet 9 inches.

A. J. D.

JANUARY 27, 1912.