OVERVIEW: Flank array sonar systems are passive detection systems mounted along the sides of a submarine hull, enhancing long-range detection and bearing accuracy in quiet operations. They have been in operational use since the 1960s and continue to evolve into modern digital variants.

GENERAL DESCRIPTION: Flank array sonars are passive linear arrays installed externally along the port and starboard sides of a submarine. These arrays detect low-frequency sound emissions from other submarines and ships, exploiting the longer aperture and broader baseline for superior azimuth resolution and bearing accuracy compared to bow-mounted arrays. Operating without active transmissions, they are especially suited for covert tracking in anti-submarine warfare (ASW). Integration with digital signal processing allows advanced target recognition and threat classification.

ROLE SUMMARY:
Category: Passive Sonar Array (Submarine)
Primary Use: Long-range target detection and tracking
Function: Passive acoustic surveillance using hull-mounted side arrays
Platform: Submarines (attack and ballistic missile types)

See Specific information under [Sensors/EW] section.

SOURCE:
Naval sonar publications and open-source defense references on submarine sensor systems