. . . . . . . "SDN:L22::TOOL1261" . . "UnSpec sonobuoy" . "UnSpec sonobuoy"@en . "Unspecified sonobuoy"@en . "accepted"@en . "An expendable underwater listening device designed to be dropped from an aircraft or a ship and deploy upon water impact. Sonobuoys include hydrophone sensors which descend underwater and send detected signals to a radio transmitter mounted on an inflatable float which stays at the surface. The transmitter subsequently sends the signals to a monitoring unit for processing, analysis and classification."@en .