The Kronshtadt-class battlecruisers, with the Soviet designation as Project 69 heavy cruisers, were ordered for the Soviet Navy in the late 1930s. Two ships were started but none were completed due to World War II. These ships had a complex and prolonged design process which was hampered by constantly changing requirements and the Great Purge in 1937.
They were laid down in 1939, with an estimated completion date in 1944, but Stalin's naval construction program was more ambitious than the shipbuilding and armaments industries could handle. Prototypes of the armament and machinery had not even been completed by 22 June 1941, almost two years after the start of construction. This is why the Soviets bought twelve surplus 38-centimeter (15.0 in) SK C/34 guns, and their twin turrets, similar to those used in the Bismarck-class battleships, from Germany in 1940. The ships were partially redesigned to accommodate them, after construction had already begun, but no turrets were actually delivered before Germany invaded the following year.
Only Kronshtadt's hull survived the war reasonably intact being 10% complete in 1945, although she was considered to be obsolete. The Soviets considered converting her into an aircraft carrier, but the idea was rejected and both hulls were scrapped in 1947.
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