Opytny was the only member of her class of destroyers built for the Soviet Navy during the 1930s. The Soviet designation for her class was Project 45. She was originally named Sergo Ordzhonikidze and was the first Soviet destroyer to be indigenously designed. Renamed Opytny in 1940, the ship was intended as a prototype for future Soviet destroyers.
German submarine U-23 was a Type IIB U-boat of Nazi Germany's Kriegsmarine, built in Germaniawerft, Kiel. She was laid down on 11 April 1936 and commissioned on 24 September.
The Vifor class was a group of four destroyers ordered by Romania in 1913 and built in Italy during the First World War. The four ships were however requisitioned by Italy in 1915 and rearmed as scout cruisers (esploratori), subsequently seeing service in World War I. Two were re-purchased by Romania in 1920 and saw service in World War II. The other two were eventually transferred by Italy to the Spanish Nationalists and saw service during the Spanish Civil War.
The Regele Ferdinand class was a pair of destroyers built in Italy for the Romanian Navy during the late 1920s. The sister ships were the most modern and powerful warships of the Axis powers in the Black Sea during World War II. During the war they participated in the 1941 Raid on Constanța and the 1944 evacuation of the Crimea, although they spent the vast majority of the war escorting convoys in the Black Sea. The Romanians claimed that they sank two submarines during the war, but Soviet records do not confirm their claims. Following King Michael's Coup, where Romania switched sides and joined the Allies in late 1944, the two ships were seized and incorporated into the Soviet Black Sea Fleet. They were returned to Romania in 1951 and served until 1961 when they were scrapped.
The Kasatka class was a class of submarines built for the Imperial Russian Navy. The six boats were built between 1904 and 1905. They were designed by I. G. Bubnov and were based on the Delfin. The first boat, Kasatka, experienced significant problems with stability on trials and had to have extra flotation added. In 1905, four of the class were transferred from Western Russia to Vladivostok with the outbreak of the Russo-Japanese War. Initially powered by a kerosene/electrical system, the boats were re-built around 1910 with a diesel-electric power plant following the end of the war. The class remained in service throughout World War I. Two were captured by the German Empire in 1918 and handed over to the British following the German surrender. They were scuttled by the British in 1919 to prevent their capture by the Soviets. The remaining four were broken up for scrap in 1922.
NMS Delfinul was a Romanian submarine that served in the Black Sea during the Second World War. It was the first submarine of the Romanian Navy, built in Italy under Romanian supervision.
SM UB-45 was a Type UB II submarine or U-boat built for and operated by the German Imperial Navy during World War I. UB-45 operated in the Mediterranean and the Black Seas, and was sunk by a mine in November 1916.
SM UB-42 was a Type UB II submarine or U-boat for the German Imperial Navy during World War I. UB-42 operated in the Mediterranean and the Black Seas during the war. She was broken up at Malta in 1920.
The Sava-class river monitors were built for the Austro-Hungarian Navy during the mid-1910s. The two ships of the class were assigned to the Danube Flotilla and participated in World War I. The ships survived the war and were transferred to Romania and the newly created Kingdom of Serbs, Croats and Slovenes as reparations.
The Enns-class river monitors were built for the Austro-Hungarian Navy during the mid-1910s. The two ships of the class were assigned to the Danube Flotilla and participated in World War I. The ships survived the war and were transferred to Romania and the newly created Kingdom of Serbs, Croats and Slovenes as reparations.
NMS Mărăști was one of four Vifor-class destroyers ordered from Italy by Romania shortly before the beginning of the First World War. All four sister ships were requisitioned when Italy joined the war in 1915. Originally named Vijelie by the Romanians, she was renamed Sparviero in Italian service. Not completed until mid-1917, the ship engaged Austro-Hungarian ships in the Adriatic Sea only twice before the war ended in November 1918. She was given a new name as Mărăști when she was re-purchased by the Romanians in 1920.
NMS Mărășești was one of four Vifor-class destroyers ordered by Romania shortly before the beginning of the First World War from Italy. All four sister ships were requisitioned when Italy joined the war in 1915. Originally named Vârtej by the Romanians, she was renamed Nibbio in Italian service. Not completed until mid-1918, the ship engaged Austro-Hungarian ships in the Adriatic Sea only once before the war ended in November. She was renamed Mărășești when she was re-purchased by the Romanians in 1920.
Moskva was one of six Leningrad-class destroyer leaders built for the Soviet Navy during the 1930s, one of the three Project 1 variants. Completed in 1938 and assigned to the Black Sea Fleet, she participated in the Raid on Constanța on 26 June 1941, a few days after the beginning of the German invasion of the Soviet Union. After the ship had finished bombarding targets in the port, she was sunk by a mine.
The Kiev class was designed in 1939 for the Soviet Navy as a smaller class of destroyer leaders after the cancellation of the Tashkent-class ships that had been intended to be built in the Soviet Union. Only three ships were begun; one was cancelled and scrapped before the Axis invasion in mid-1941 and construction of the other two was suspended during the war. The navy considered completing them under a new Project 48-K configuration afterwards, but decided against that as they would have been competing against a more modern design that lacked the stability problems that the 48-K design would have had. The Soviets either scrapped them or used them as targets.
The Saphir-class submarines were a class of six submarines built in France between 1926 and 1935 for the French Navy. Most saw action during World War II for the Vichy French Navy or the Free French Naval Forces. Three were captured by Italian forces but not used.
NMS Regele Ferdinand was the lead ship of her class of two destroyers built in Italy for the Romanian Navy in the late 1920s. After the Axis invasion of the Soviet Union on 22 June 1941, she was limited to escort duties in the western half of the Black Sea during the war by the powerful Soviet Black Sea Fleet which heavily outnumbered Axis naval forces in the Black Sea. The ship may have sunk two Soviet submarines during the war. In early 1944 the Soviets were able to cut off and surround the port of Sevastopol on the Crimean Peninsula. Regele Ferdinand covered convoys evacuating Axis troops from Sevastopol and was badly damaged in May when she rescued some troops herself.
NMS Regina Maria was the second and last of the two Regele Ferdinand-class destroyers built in Italy for the Romanian Navy in the late 1920s. After the Axis invasion of the Soviet Union on 22 June 1941, she took part in the Raid on Constanța a few days later and may have damaged a Soviet destroyer leader during the battle. The powerful Soviet Black Sea Fleet heavily outnumbered Axis naval forces in the Black Sea and the Romanian destroyers were limited to escort duties in the western half of the Black Sea during the war. In early 1944 the Soviets were able to cut off and surround the port of Sevastopol on the Crimean Peninsula. Regina Maria covered convoys evacuating Axis troops from Sevastopol in May and rescued several hundred herself.
The Lagrange-class submarines were a class of four submarines built for the French Navy during World War I and the interwar period. Three ships of this type were built in the Arsenal de Toulon from 1913 to 1924, and one was built at the Arsenal de Rochefort shipyard. Entering the French Marine Nationale from 1918 to 1924, the submarines served until the mid-1930s.
Ro-42 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in August 1943, she served in World War II and was sunk in June 1944 during her third war patrol.
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