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-652 The 3,410 ton merchant ship "Baron Pentland" remained afloat due her cargo of timber despite a broken back, but was later torpedoed and sunk by on 19 September. On 4 September 1941, off Iceland, the American destroyer received a signal from a British bomber that a German submarine was in the vicinity. "Greer" made sonar contact, and pursued the "U-652" at close range. The aircraft dropped four depth charges, and soon after the U-boat fired a torpedo at the US warship, perhaps believing she had launched the attack. "Oblt.z.S." Fraatz also misidentified the destroyer as ""one of the 50 American