AN/BQQ-5 bow-mounted spherical array sonar acoustic system is deployed on SSN 637 and SSN 688 attack submarine classes. This low frequency passive and active search and attack sonar is supplied by IBM. The AN/BQQ-5E sonar with the TB-29 towed array and Combat Control System (CCS) Mk 2, known collectively as the QE-2 System, provides a functionally equivalent system for the Los Angeles (SSN-688) and Ohio (SSBN-726)-class submarines. Enhancements include increases in acoustic performance, improved combat control capabilities and replacement of obsolete equipment.

OPEVAL for AN/BQQ-5E system with the TB-29 Array completed in FY 1998; this system will provide quantum improvements in long-range detection and localization for SSN 688 and SSBN 726 Class Submarines. Engineering Change Proposal (ECP) 7001 to AN/BQQ-5E will provide Low Frequency Active Interference Rejection, Dual Towed Array Processing, and Full Spectrum Processing to SSN 688 and SSBN 726 Class Submarines.

The AN/BSY-1 ECP 1000, the AN/BQQ-5 Medium Frequency Active Improvement program and Improved Control Display Console Obsolete Equipment Replacement have been modified to become the basis of the Acoustics Rapid Commercial Off The Shelf Insertion (A-RCI) program. A-RCI is a multi-phased, evolutionary development effort geared toward addressing Acoustic Superiority issues through the rapid introduction of interim development products applicable to SSN 688, 688I Flight, and SSBN 726 Class Submarines. A-RCI Phases I and II introduce towed array processing improvements; A-RCI Phase III introduces spherical array processing improvements.

The Trident Submarine System Improvement Program develops and integrates command and control improvements needed to maintain Trident submarine operational capability through the life cycle of this vital strategic asset. The program conducts efforts needed to ensure platform invulnerability, and reduce life cycle costs. Recent efforts have included the development of AN/BQQ-6 Sonar to AN/BQQ-5E Sonar Translator.