RMS Mauretania (1906) launched by the Duchess of Roxburghe. At the time of her launch, she was the largest moving structure ever built, and slightly larger in gross tonnage than "Lusitania". The main visual differences between "Mauretania" and "Lusitania" were that "Mauretania" was five feet longer and had different vents. "Mauretania" also had two extra stages of turbine blades in her forward turbines, making her slightly faster than "Lusitania". "Mauretania" and "Lusitania" were the only ships with direct-drive steam turbines to hold the Blue Riband; in later ships, reduction-geared turbines were mainly used. "Mauretania"s usage of the steam turbine was the largest application
German submarine U-311 German submarine U-311 German submarine "U-311" was a Type VIIC U-boat of Nazi Germany's "Kriegsmarine" during World War II. The submarine was laid down on 21 March 1942 at the Flender Werke yard at Lübeck as yard number 311, launched on 20 January 1943 and commissioned on 23 March under the command of "Kapitänleutnant" Joachim Zander. During her short career, the U-boat sailed on two combat patrols, sinking a single ship, before she was sunk on 24 April 1944. German Type VIIC submarines were preceded by the shorter Type VIIB submarines. "U-311" had a displacement of when at the surface