BAE has been awarded a $7.8 million contract (cost plice incentive fee) to produce up to three “compact low frequency active transmit systems”, replacement sensors for the Navy’s SURTASS towed sonar array systems.  These active sonar are used at low frequency to detect potential threats at long range that might not show up on passive surveillance because they are too quiet.  They can also be used for “ocean mapping”.

SURTASS is the mobile element of the Integrated Undersea Surveillance System, the follow-on to the SOSUS system made famous by Tom Clancy’s The Hunt for Red October . The SURTASS system is long-range sonar surveillance system, towed by T-AGOS ocean surveillance ships (like the one recently harrassed by Chinese sailors).