August 6, 2011: Chile is buying British Sonar 2087 towed sonar systems for their three Type 23 frigates. Britain introduced Sonar 2087 six years ago. In addition to being more effective, Sonar 2087 is less annoying to aquatic non-combatants (the fish). The new sonar does this by relying more on passive (just listening) detection, and broadcasting on frequencies that do not annoy the fish and whales. Of course, any new noise broadcast into the ocean will annoy the sea creatures there, but some noises are more of a problem than others. The new sonar is a towed array, which is let loose from the rear of the ship. Sonar 2087 remains connected via a cable, and then lowered to the optimum depth for listening or broadcasting (like radar.) The new towed array can be used at higher ship speeds, and can be deployed, and recovered, in rougher seas (up to Sea State 6). Also included are the most modern electronics and software. Britain has already installed the new sonar on six of its Type 23 frigates. These 4,900 ton warships are the backbone of the Royal Navy’s anti-submarine forces. And Chile bought three of them for that reason.