The Leninets or L class were the second class of submarines to be built for the Soviet Navy. Twenty-five were built in four groups between 1931 and 1941. They were minelaying submarines and were based on the British L-class submarine, HMS L55, which was sunk during the British intervention in the Russian Civil War. Some experience from the previous Dekabrist-class submarines was also utilised. The boats were of the saddle tank type and mines were carried in two stern galleries as pioneered on the pre-war Russian submarine Krab (1912). These boats were considered successful by the Soviets. Groups 3 and 4 had more powerful engines and a higher top speed.
The Black Sea Campaigns were the operations of the Axis and Soviet naval forces in the Black Sea and its coastal regions during World War II between 1941 and 1944, including in support of the land forces.
Щ-213 was a Soviet Navy Shchuka-class submarine, Type X. She was built at the Sudostroytelnyi zavod imeny 61 kommunara in Mykolaiv, Ukrainian SSR, and entered service in October 1938 with the Soviet Black Sea fleet.
Shch-317 was a Shchuka-class submarine of the Soviet Navy. Her keel was laid down by A. Marti in Leningrad on 23 July 1934. She was launched on 24 September 1935 and commissioned on 29 September 1936 in the Baltic Fleet.
Soviet submarine K-3 was a K-class submarine of the Soviet Navy during World War II.
Submarine warfare in the Black Sea in World War II during 1941 primarily involved engagements between submarines of the Soviet Black Sea Fleet attacking Axis merchantmen defended by Romanian and Bulgarian warships. These engagements were a part of the naval Black Sea campaigns between Axis and Soviet naval forces.
The Romanian Navy during World War II was the main Axis naval force in the Black Sea campaigns and fought against the Soviet Union's Black Sea Fleet from 1941 to 1944. Operations consisted mainly of mine warfare, but there were also escort missions and localized naval engagements. The largest naval action fought by the Romanian Navy was the 26 June 1941 Raid on Constanța, and its most extensive operation was the 1944 evacuation of the Crimea.
The action of 6 December 1941 was a confrontation between the Bulgarian and Soviet navies in the Black Sea during World War II, taking place near the Bulgarian coast at Cape Emine.
The action of 9 July 1941 was a naval engagement between the Soviet and Romanian navies during World War II, taking place near the Romanian port-city of Mangalia.
The Soviet Black Sea Fleet during the first years of the Black Sea campaigns (1941–44) conducted raiding operations along the Western coast of the Black Sea aimed to disrupt Axis communications and supplies by sea.
The Soviet submarine Baltic Sea campaign in 1943 was launched by the Soviet Navy to harass the strategic iron ore traffic from neutral Sweden to Nazi Germany on the Eastern Front during the WWII. Other operations were launched by Allies, especially by the Royal Navy. The offensive was a repetition of the previous campaign in 1942 but resulted in a failed outcome.
Submarine warfare in the Black Sea in World War II during 1943 involved engagements between submarines of the Soviet Black Sea Fleet attacking Axis merchantmen defended by Romanian and German naval warships, as well as and German U-boats attacking Soviet merchants on the eastern Black Sea. These engagements were a part of the Black Sea campaigns between Axis and Soviet naval forces.
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 Soviet submarine Baltic Sea campaign in 1941 was launched by the Soviet Navy at the early stage of Operation Barbarossa. The offensive was hampered by the quick German ground advance and the retreat of Soviet naval vessels from the main Baltic harbors.
The Soviet submarine Baltic Sea campaign in 1944 was launched by the Soviet Navy to harass enemy shipping and naval military assets of the Nazi Germany on the Eastern Front during World War II.
The Soviet naval Baltic Sea campaign in 1945 was launched by the Soviet Navy to harass enemy shipping and naval military assets of Nazi Germany on the Eastern Front during World War II. Both submarines and surface units of the Soviet Navy were employed. The campaign scored successes during Operation Hannibal.
Between 1941 and 1944, Romania held control over much of the Ukrainian Black Sea coast East of the Crimea. This was acquired during Operation Barbarossa. The Romanian conquest of the Soviet Western Black Sea coast started in July 1941 during Operation München and ended in October that year, after the Siege of Odessa. In the aftermath of these actions, Romania (re)acquired two new sectors of coastline: the Bessarabian coast and the Transnistrian Coast. The latter was lost in April 1944, but the former was successfully defended until August 1944.
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.
Shch-310 was a Shchuka-class submarine of the Soviet Navy. She operated in the Baltic Sea during the WW2. During the operations in 1942 the submarine's commander was Georgiy Yegorov.
Shch-421 was a Shchuka-class submarine of the Soviet Navy. She served in the Northern Fleet during World War II. She was led by commander Nikolai Lunin, before he was replaced by his second-in-command Fyodor Vidyayev.
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