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-24 (1936) by the Soviet Union in early 1945, but sunk as target practice by the on 26 May 1947, off Sevastopol (also sunk that same day was the former ). German submarine U-24 (1936) German submarine "U-24" was a Type IIB U-boat that was in service of Nazi Germany's "Kriegsmarine" during World War II. She was laid down on 21 April 1936 at the F. Krupp Germaniawerft in Kiel with yard number 554, launched on 24 September and commissioned into the "Kriegsmarine" on 10 October. "Oberleutnant zur See" Heinz Buchholz took command on 3 July 1937. German Type IIB submarines were