AN/BQQ-6

The AN/BQQ-6 was a hull-mounted, passive sonar system adopted from the AN/BQQ-5 passive/active sonar system for use with the Mk 118 torpedo fire-control system on board the OHIO class ballistic missile submarines.

Given the low self-noise on the OHIO class, this system was likely a very effective self-defense sonar. The system had 944 hydrophone transducers mounted on a sphere and 100 transducers in two flank arrays.

The BQQ-6 was replaced in the OHIO class by an upgraded version...