HMS Alcantara was an ocean liner built by Harland and Wolff in Govan for the Royal Mail Steam Packet Company, launched on 30 October 1913. As part of RMSP's "A-series" of liners, she featured three screw propellers driven by twin four-cylinder triple-expansion steam engines, with a central low-pressure turbine powered by exhaust steam. Alcantara was designed for long-distance passenger service, making her maiden voyage in June 1914 from Southampton to South America, specifically to Rio de Janeiro, Montevideo, and Buenos Aires. She was registered at Belfast, bearing the UK official number 132050 and the code letters JFPR. In April 1915, Alcantara was requisitioned by the British Admiralty and converted into an armed merchant cruiser, armed with eight 6-inch guns, two six-pounder anti-aircraft guns, and depth charges. She was commissioned into the Royal Navy's 10th Cruiser Squadron as HMS Alcantara, with the pennant number M 94. Her role involved patrolling the North Sea, Norwegian Sea, and Arctic Ocean as part of the blockade of the Central Powers, along with her sister ships Avon, Arlanza, and Andes. Notably, Alcantara participated in an Arctic expedition to Jan Mayen Island in July 1915 to investigate German submarine activity suspected in the area, but found no evidence of enemy presence. Her service culminated in her engagement with the German merchant raider SMS Greif on 29 February 1916 northeast of Shetland. During the Action of 29 February 1916, Alcantara attempted to inspect the disguised Greif, which opened fire upon her. Despite initial damage and the disabling of her steering gear, Alcantara engaged in a fierce combat, hitting Greif and causing her to catch fire. Ultimately, Alcantara was heavily damaged, capsized, and sank at 1102 hours, with at least 68 casualties. The battle resulted in the sinking of Greif and the rescue of 210 German survivors, marking a significant naval encounter in the First World War.

This description has been generated using GPT-4.1-NANO based on the Vessel's wikidata information and then modified by ShipIndex.org staff.