The Titanic Struck a Glancing Blow Against an Under-water Shelf of the Iceberg, Opening Up Five Compartments. Had She Been Provided With a Watertight Deck At or Near the Water Line, the Water Which Entered the Ship Would Have Been Confined Below That Deck, and the Buoyancy of That Portion of the Ship Above Water Would Have Kept Her Afloat. As It Was, the Water Rose Through Openings in the Decks and Destroyed the Reserve Buoyancy
Whatever may have been the depth of the injury, it is certain from the evidence that the six forward compartments were opened to the sea. Immediately after the collision the whistling of air, as it issued from the escape pipe of the forepeak tank, indicated that the tank was being filled by an inrush of water. The three following compartments, in which were located the baggage-room and mail-room, were quickly flooded. Leading fireman Barrett, who was in the forward boiler-room, felt the shock of the collision. Immediately afterwards he saw the outer skin of the ship ripped open about two feet above the floor, and a large volume of water came rushing into the ship. He was quick enough to jump through the open door in the bulkhead separating boiler-rooms 6 and 5, before it was released from the bridge. The damage just abaft of this bulkhead admitted water to the forward coal-bunker of room No. 5, which held for a while, but being of non-watertight and rather light construction, must have soon given way; for the same witness testified to a sudden rush of water coming across the floor-plates between the boilers.
In spite of the frightful extent of the damage, the Titanic, because of the great height to which her plated structure extended above the water-line, and the consequent large amount of reserve buoyancy which she possessed, would probably have remained afloat a great many hours longer than she did, had the deck to which her bulkheads extended been thoroughly watertight. As it was, this deck (upper deck E) was pierced by hatchways and stairways which, as the bow settled deeper and deeper, permitted the water to flow up over the deck and pass aft over the tops of the after bulkheads and so-called watertight compartments. See page [129].
Now, it so happened that for the full length of the boiler-rooms there had been constructed on upper deck E what was known as the "working-crew alleyway." On the inboard side of this passage six non-watertight doors opened on to as many iron ladders leading down to the boiler-rooms. Not only were these doors non-watertight, but they consisted of a mere open frame or grating, this construction having been adopted, doubtless, for purposes of ventilation. Unfortunately, although there was a watertight door at the after end of this alleyway, there was none at its forward end. The water which boiled up from the forward flooded compartments, as it flowed aft, poured successively through the open grating of the alleyway doors, flooding the compartments below, one after the other.
TITANIC 1912
MAURETANIA 1906
Titanic: Single skin, 16 compartments; Mauretania: double skin, 34 compartments.
Comparison of Subdivision in Two Famous Ships
It does not take a technically instructed mind to understand from this that the safety elements of the construction of the Titanic were as faulty above the water-line as they were below it. The absence of an inner skin and the presence of these many openings in her bulkhead deck combined to sink this huge ship, whose reserve buoyancy must have amounted to at least 80,000 tons, in the brief space of two and one-half hours.