Thursday, March 27, 2008


White Star gave Harland and Wolff complete freedom to build the very best ships they could, adding a percentage profit to the final cost of the building. The so-called "cost-plus" arrangement was used on all but one of the company's ships. From 1869 until 1919, it was said that there was never a single day that Harland and Wolff was not working on one of the White Star Line's ships. White Star was Harland and Wolff's best customer and they undertook to build Olympic and Titanic on the same basis as before, cost-plus. The ships were the largest in the world and would require numerous calculations as to the strength of hull required at this size. Much of the ships' arrangement was tried and tested basic shipbuilding design -- just larger with greater added strength. The strength was entirely provided by the ship's shell plating and rivets. Hydraulic riveting was used for much of the 3 million rivets, in some places the hull quadruply riveted.

Titanic's impact with an iceberg caused the rippling and springing of the joints between plates. Rivet heads ripped off would not cause massive flooding, rather the long leaking that is recorded to have happened in her forward compartments. Science tells us that in order for steel of this quality to fracture due to cold and impact would mean the steel being brought down to below the temperature of liquid nitrogen. As the water in Titanic's ballast tanks had not frozen on the night she struck the iceberg, it's safe to say the steel was above the freezing point of ordinary seawater.

We discovered on the Arabic (White Star liner of 1903) dive the ship's shell plating was in remarkable condition, but the rivets had "let go." That is to say, sprung -- allowing the plates to come apart. In places the ship was like a stack of playing cards not relating to any structure. I have some of these and I'm organizing a scientific study of them and will keep you apprised of the results.

I think -- and this is just a theory -- the rivets were heated so they could be riveted into place by hand or by hydraulic riveter. The steel would have to be capable of easy heating, malleable, and perhaps weaker by design. Is this the Achilles' heel of the Titanic? So much time is spent looking at the steel but I think these 3 million mild steel rivets might hold the secret.

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