As with missile boats, this led to confusion as the same Russian word could be both the official Soviet designation of one submarine class and the NATO reporting name of a different one. For example, Akula (shark) was both the NATO reporting name for an attack submarine and the Soviet designation of a ballistic missile submarine.
The use of the Russian term "Akula" (shark), which could represent different submarine classes in official Soviet designations and NATO reporting names, caused confusion. For example, Akula was used as both the NATO name for an attack submarine and the Soviet designation for a ballistic missile submarine.