HMS Upholder (P37) was a Royal Navy U-class submarine constructed by Vickers-Armstrongs at Barrow-in-Furness. Laid down on October 30, 1939, and launched on July 8, 1940, she was commissioned later that year on October 31. Upholder featured a distinctive design with two external bow torpedo tubes in addition to the four internal ones common to all U-class submarines. These external tubes were incorporated to avoid interference with depth-keeping at periscope depth, a design consideration specific to her class. Throughout her service, Upholder was commanded by Lieutenant-Commander Malcolm David Wanklyn, under whom she became the most successful British submarine of World War II. After initial working-up, she departed for Malta on December 10, 1940, joining the 10th Submarine Flotilla. Over her operational career, she completed 24 patrols, during which she sank approximately 93,031 tons of enemy shipping, including four warships: the Italian destroyer Libeccio, two submarines (Tricheco and Ammiraglio Saint-Bon), and an auxiliary minesweeper. She also sank ten merchant ships, comprising troopships, cargo vessels, and an auxiliary transport. Upholder's most notable actions included the sinking of the Italian troopship Conte Rosso and damaging other significant vessels like Giuseppe Garibaldi. She sank two Italian sister troopships, Neptunia and Oceania, within hours of each other in September 1941, and damaged several other enemy vessels. Her crew, under Wanklyn’s command, earned a reputation for skill and daring, exemplified by Wanklyn's Victoria Cross award for a 1941 patrol. The submarine was lost with all hands on her 25th patrol, likely due to a mine or attack by Italian forces near Tripoli in April 1942. Despite some conflicting theories about her sinking, recent research suggests she was most probably lost to a naval mine while intercepting a convoy. Her loss was officially announced in August 1942, and she was remembered for her exceptional service, inspiring future naval efforts despite her ultimate fate.

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