Loss of the Steamship "Titanic"

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

At the forward end the framing and plating was strengthened with a view to preventing panting and damage when meeting thin harbor ice.

Beams were fitted on every frame at all decks from the boat deck downward. An external bilge keel about 300 feet long and 25 inches deep was fitted along the bilge amidships.

The heavy ship's plating was carried right up to the boat deck, and between the C and B decks was doubled. The stringer or edge plate of the B deck was also doubled. This double plating was hydraulic riveted.

All decks were steel plated throughout.

The transverse strength of the ship was in part dependent on the 15 transverse water-tight bulkheads, which were specially stiffened and strengthened to enable them to stand the necessary pressure in the event of accident, and they were connected by double angles to decks, inner bottom, and shell plating.

The two decks above the B deck were of comparatively light scantling, but strong enough to insure their proving satisfactory in these positions in rough weather.

Water-tight subdivision.—In the preparation of the design of this vessel it was arranged that the bulkheads and divisions should be so placed that the ship would remain afloat in the event of any two adjoining compartments being flooded and that they should be so built and strengthened that the ship would remain afloat under this condition. The minimum freeboard that the vessel would have in the event of any two compartments being flooded was between 2 feet 6 inches and 3 feet from the deck adjoining the top of the water-tight bulkheads. With this object in view, 15 water-tight bulkheads were arranged in the vessel. The lower part of C bulkhead was doubled and was in the form of a cofferdam. So far as possible the bulkheads were carried up in one plane to their upper sides, but in cases where they had for any reason to be stepped forward or aft, the deck, in way of the step, was made into a water-tight flat, thus completing the water-tightness of the compartment. In addition to this, G deck in the after peak was made a water-tight flat. The orlop deck between bulkheads which formed the top of the tunnel was also water-tight. The orlop deck in the forepeak tank was also a water-tight flat. The electric-machinery compartment was further protected by a structure some distance in from the ship's side, forming six separate water-tight compartments, which were used for the storage of fresh water.

Where openings were required for the working of the ship in these water-tight bulkheads they were closed by water-tight sliding doors which could be worked from a position above the top of the water-tight bulkhead, and those doors immediately above the inner bottom were of a special automatic closing pattern, as described below. By this subdivision there were in all 73 compartments, 29 of these being above the inner bottom.

Water-tight doors.—The doors (12 in number) immediately above the inner bottom were in the engine and boiler room spaces. They were of Messrs. Harland & Wolff's latest type, working vertically. The doorplate was of cast iron of heavy section, strongly ribbed. It closed by gravity, and was held in the open position by a clutch which could be released by means of a powerful electromagnet controlled from the captain's bridge. In the event of accident, or at any time when it might be considered desirable, the captain or officer on duty could, by simply moving an electric switch, immediately close all these doors. The time required for the doors to close was between 25 and 30 seconds. Each door could also be closed from below by operating a hand lever fitted alongside the door. As a further precaution floats were provided beneath the floor level, which, in the event of water accidentally entering any of the compartments, automatically lifted and thus released the clutches, thereby permitting the doors in that particular compartment to close if they had not already been dropped by any other means. These doors were fitted with cataracts, which controlled the speed of closing. Due notice of closing from the bridge was given by a warning bell.

A ladder or escape was provided in each boiler room, engine room, and similar water-tight compartment, in order that the closing of the doors at any time should not imprison the men working therein.