Captas

Captas is a family of towed-array sonar systems developed by Thales (formerly Thomson-CSF). The systems consist of long hydrophone arrays towed behind a vessel or submarine, paired with sophisticated signal processing to provide broad-band passive listening and active sonar capabilities. By operating at depth and away from the host platform, the towed array reduces self-noise and hull-generated interference, enabling detection of quieter submarines at long ranges across varied sea states.

Several CAPTAS variants have been produced, including CAPTAS-2, CAPTAS-3, and CAPTAS-4. Each version reflects advances in array design, processing power, and deployment flexibility, offering different ranges, tow profiles, and integration options with a platform’s combat-management systems. The systems support both passive surveillance and active ping modes and are designed to be compatible with modern naval networks and sensors.

CAPTAS-equipped ships and submarines are operated by multiple navies around the world for anti-submarine warfare, maritime patrol, and submarine detection missions. The system entered service in the late 1990s and has evolved through several production cycles to address changing threat environments and operating conditions. It is part of a broader family of towed-array sonars used to extend a platform’s sensing reach, complementing hull-mounted sonars and other underwater sensors.