The Varshavyanka-type submarine, which combines 877 and 636 projects, is the main class of non-nuclear submarines manufactured in Russia. These boats were developed in the late 70s of the last century. Initially it was assumed that they would be built and exported to the Warsaw Pact countries in large quantities. Therefore, the 877 “Halibus” project, which later transformed into the 636 project, began to carry the name “Varshavyanka”.
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