The sonar room is dominated by sonar consoles. Two modes of sonar observation are used. In the "active" mode, the echoes of sound waves sent out from the sub are timed and analyzed. In the passive ...

Sonar 2087 equips eight RN Type 23 frigates. Pictured here is the sonar room of HMS Westminster – the sonar director is nearest to the camera, with the four dual-screen sonar operator consoles ...

Their system, called CovertBand, emits high-pitched sonar signals hidden within popular songs—their examples include songs by Michael Jackson, Justin Timberlake, and 2Pac—then records them ...