Feniks

The early Soviet surface ships of the post-World War II period largely utilized the Tamir-5 series of high-frequency, hull-mounted sonars. They were succeeded from the mid-1950s by the Pegas-2 series sonars and then, after the late 1950s, by the Herkules series.

Subsequently, various improved sonars were developed for the Soviet warships that began joining the fleet in the 1960s. By the 1960s, as the Soviet navy became more concerned with anti-submarine warfare...