Titanic: was it all right when it left here?

Titanic rivets

Not according to metallurgists Tim Foecke and Jennifer Hooper McCarty whose research has suggested that dodgy Harland and Wolff rivets were at fault for allowing the Titanic’s hull to be ripped apart by the pressure of the iceberg impact.

With six of the hull’s chambers exposed to the Atlantic waters, the “unsinkable” ship lasted less than three hours, not enough time for rescue boats to reach those (disproportionately poorer) passengers left without access to a lifeboat (the White Star line failed to supply enough for all on board, although interestingly, this was still more than was required by law). As a result, 1,514 men, women and children died. Today, a sinking under such circumstances would likely result in a case of corporate manslaughter.

Science writer Richard Corfield picks up the story in a fascinating article in the current issue of Physics World (which I try to never miss):

In the mid-2000s two metallurgists, Tim Foecke at the US National Institute of Standards and Technology and Jennifer Hooper McCarty, then at Johns Hopkins University in the US, focused their attention on the composition of the Titanic’s rivets. They combined their metallurgical analysis with a methodical sweep through the records of the Harland and Wolff shipyard in Belfast where the Titanic was built. Combining physical and historical analysis in this way proved to be a powerful trick.

Foecke and McCarty found that the rivets that held the mild-steel plates of the Titanic’s hull together were not of uniform composition or quality and had not been inserted in a uniform fashion. Specifically, Foecke and McCarty found that the rivets at the front and rear fifths of the Titanic were made only of “best” quality iron, not “best-best”, and had been inserted by hand. The reason for this was that, at the time of the Titanic’s construction, the hydraulic presses used to insert the rivets used in the middle three-fifths of the ship could not be operated where the curvature of the hull was too acute (i.e. at bow and stern).

But why did Harland and Wolff use “best” quality rivets rather than “best-best?” Foecke and McCarty speculate that it may simply have been a cost-saving exercise. “Best” rivets were cheaper than “best-best” but also had a higher concentration of impurities known as “slag”. This higher concentration of slag meant that the rivets were particularly vulnerable to shearing stresses – precisely the kind of impact they were subjected to that long-ago night in April 1912. Lab tests have shown that the heads of such rivets can pop off under extreme pressure, which on the Titanic would have allowed the steel plates on the hull to come apart, exposing her inner chambers to an onslaught of water.

The allegedly dodgy rivets are only part of “a perfect storm” of reasons outlined by Corfield for the sinking of the Titanic – the absence of binoculars in the crow’s nest; the high speed despite the iceberg warnings; the radio operators’ tardiness in getting crucial information to officers; the lack of lifeboats; the interplay of two ocean currents; and the high spring tide, all figure.

Yet, it does beg the question, amidst all the hype surrounding the opening of Titanic Belfast: ‘was it all right when it left here?’

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