HMS Triton was a submarine of the Royal Navy named for the son of Poseidon and Amphitrite, the personification of the roaring waters. She was the lead ship of the T class of diesel-electric submarines. Her keel was laid down on 28 August 1936 by Vickers Armstrong at Barrow-in-Furness. She was launched on 5 October 1937, and commissioned on 9 November 1938.
HMS Triumph (N18) was a T-class submarine of the Royal Navy. She was laid down by Vickers at Barrow-in-Furness and launched in 1938. The boat was lost in transit in 1942, with a crew of 64, and its fate was unknown until the sunken boat was rediscovered in June 2023.
Lieutenant Commander Malcolm David Wanklyn, was a Royal Navy commander and one of the most successful submariners in the Western Allied navies during the Second World War. Wanklyn and his crew sank 16 enemy vessels.
Nürnberg was a German light cruiser of the Leipzig class built for the Kriegsmarine. She was named after the city of Nuremberg and had one sister ship, Leipzig. Nürnberg was laid down in 1934, launched in December of that year, and completed in November 1935. She was armed with a main battery of nine 15 cm (5.9 in) guns in three triple turrets and could steam at a speed of 32 knots. Nürnberg was the longest-serving major warship of the Kriegsmarine, and the only one to see active service after the end of World War II, though not in a German navy.
HMS Sickle was a third-batch S-class submarine built for the Royal Navy during World War II. Completed in 1942, she made her initial war patrol off the Norwegian coast. Sickle then sailed to Gibraltar, from where she conducted one patrol, then to Algiers, French North Africa. From 10 May to 10 October, the boat patrolled the Gulf of Genoa five times and sank a German submarine as well as three minesweepers and an escort ship. She then moved to Beirut, French Lebanon, and conducted two patrols in the Aegean Sea, sinking three caïques and a merchant ship, in addition to landing resistance operatives in Greece.
HMS Saracen was a third-batch S-class submarine built for the Royal Navy during the Second World War. Completed in 1942, Saracen conducted a patrol in the North Sea where she sank a German U-boat. She was then assigned to the 10th Submarine Flotilla in Malta, from where she made three patrols; on her second, she sank an Italian submarine. Saracen was then reassigned to the 8th Submarine Flotilla, based in Algiers, French North Africa.
HMS Sahib was a third-batch S-class submarine built for the Royal Navy during the Second World War. She was launched on 19 January 1942 and commissioned on 13 May 1942. She was the only British naval vessel to bear the name Sahib.
HMS Sunfish was a Royal Navy S-class submarine which was launched on 30 September 1936 and served in the Second World War. Sunfish is one of 12 boats named in the song Twelve Little S-Boats.
HMS Truant (N68) was a T-class submarine of the Royal Navy. She was laid down by Vickers Armstrong, Barrow and launched on 5 May 1939.
HMS Tigris was a T-class submarine of the Royal Navy. She was laid down at Chatham Dockyard and launched in October 1939.
HMS Ultor (P53) was a Royal Navy U-class submarine built by Vickers-Armstrong at Barrow-in-Furness, launched in 1942, and part of the third group of the class. So far she has been the only ship of the Royal Navy to bear the name Ultor.
HMS Unbroken (P42) was a Royal Navy U-class submarine built by Vickers-Armstrong at Barrow-in-Furness; it was part of the third group of that class and has been the only vessel of the Royal Navy to bear the name. She entered service as P42 and was renamed Unbroken on 1 February 1943.
HMS Unrivalled (P45) was a U-class submarine built for the Royal Navy during World War II. The boat has been the only ship of the Royal Navy to ever bear the name Unrivalled. Completed in 1942, the boat spent most of the war in the Mediterranean. She sank a number of small merchant ships and naval auxiliaries, but major success eluded her during the war. Too small and slow for the post-war environment, Unrivalled was scrapped in 1946.
Vice-Admiral Sir Arthur Richard Hezlet, nicknamed Baldy Hezlet, was a decorated Royal Navy submariner. He became the Royal Navy's youngest captain at the time – aged 36 – and its youngest admiral, aged 45. In retirement he became a military historian.
Yaroslav Iosseliani (1912–1978) was a Soviet Navy submarine commander of Georgian ethnicity. He was awarded the honorary title Hero of the Soviet Union.
HMS Westcott (D47) was a Royal Navy Admiralty W-class destroyer that served in the Second World War. In the Second World War Westcott served in an anti-submarine role and escorted numerous Atlantic and Malta convoys.
Arctic naval operations of World War II were the World War II naval operations that took place in the Arctic Ocean, and can be considered part of the Battle of the Atlantic and/or of the European Theatre of World War II.
HMS Ekins (K552) was a British Captain-class frigate of the Royal Navy that served during World War II. Originally constructed as a United States Navy Buckley class destroyer escort, she served in the Royal Navy from 1943 to 1945.
Submarine warfare in the Black Sea in World War II during 1944 involved engagements between submarines of the Soviet Black Sea Fleet attacking Axis merchantmen, defended by Romanian and German naval warships, as well as German U-boats and Romanian submarines attacking Soviet merchants on the eastern Black Sea. Before the conclusion of the campaign, Romania joined the Allies after King Michael's Coup. These engagements were a part of the naval Black Sea campaigns.
The Barents Sea campaign in 1941 was a submarine operation in the Arctic waters of the Barents Sea during World War II. It was a combined Soviet and British campaign, with boats departing from Polyarny to harass German shipping along the Norwegian coast.
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