The mystery has remained unsolved for nearly a century. The RMS Titanic was a 46,000-ton, double-hulled marvel of modern engineering. Unsinkable, people called it. Why then on April 14, 1912, did a glancing blow off an iceberg cause the Titanic to sink into the depths of the North Atlantic in less than three hours? For decades after the sinking, scientists offered up different theories. Perhaps, many speculated, it was the brittleness of the ship’s hull, an attack by a German U-boat, or a patch of low-lying pack ice that was to blame.
Enter Jennifer Hooper McCarty (MSE ’99, PhD ’03). She has spent the last decade studying remnants of the Titanic recovered from the ocean floor, examining their makeup, testing their strength, and researching how and where they were made.
Along with her coinvestigator, Tim Foecke, a materials scientist with the National Institute of Standards and Technology and a Whiting School adjunct professor, what she found in the first-ever hands-on forensic investigation was surprising.
“It was sort of like the unzipping of a seam,” explains McCarty, who details her findings in the book she co-wrote with Foecke, What Really Sank the Titanic: New Forensic Discoveries (Citadel Press, 2008). “This enormous ship that was supposed to be unsinkable sank in less than three hours because of 12 square feet of damage.”
They determined that the 6-inch-long rivets used in the Titanic’s bow and stern were hand-forged from wrought iron—not steel—in order to save money and meet deadlines. Some of the iron rivets, which had been made and installed by apprenticed and sometimes less- experienced workers, contained a high concentration of slag. While the glasslike substance adds strength at smaller concentrations (2 to 3 percent), the duo concluded that the higher concentration of slag weakened the wrought- iron rivets. Thus, the rivets popped under the stress caused by the ship’s contact with the iceberg, resulting in the flooding of five or six watertight compartments. Had the rivets been stronger, fewer compartments would have been compromised and the mighty ship would have remained afloat for several more hours enough time for the nearby Carpathia to rescue all those on board, McCarty hypothesizes.
McCarty began her research on the Titanic while she was still at Hopkins, where she won a Carl E. Heath Jr. Fellowship for women in engineering. In 1999 when her advisor, Professor Tim Weihs, asked her if she would be interested in studying some 45 riv-ets from the Titanic for her dissertation in materials science, she jumped at the chance. “I’ve always liked the historical aspect of materials science,” says McCarty, who cur- rently works as a clinical assistant professor at Oregon Health & Science University in Portland, Oregon. At Hopkins, her research started in the lab, where she looked at the rivets under the microscope, tested them mechanically, and created computer models to see how the rivets responded under condi- tions similar to the iceberg collision.
Following completion of her PhD she spent two years in England delving through records and correspondence detailing how the Titanic was built. “At times I really did feel like a detective,” she recalls.
For her next project, McCarty is interested in researching and writing about the building of the Eiffel Tower. “I’m just fascinated by this whole iron and steel age,” she says. “I love the idea of bringing people into the story of Gustave Eiffel and why he was so incredible as a designer and a builder; [I want to] talk about how the Eiffel Tower was built and why it has stood all of these years.”