have been deployed to Iraq. A communications relay payload for the Scan Eagle is under development. It includes streaming video and Voice-over Internet Protocol communications.2


This section presents a survey of current and planned ASW sensors.

In brief, the ASW mission today involves ship, submarine, and airborne sensors, together with arrays of sonar sensors deployed on the ocean floor. Surface combatant ships and attack submarines carry hull-mounted sonars and towed arrays. Fixed-wing aircraft and helicopters carry magnetic anomaly detection sensors; traditional EO, IR, SIGINT, and radar systems; sensors optimized for detecting periscopes in sea clutter; and dipping sonars. A class of noncombatant ships keeps station in specific ocean areas and tows sonar arrays. Several types of deployed sonar arrays exist or are under development. The arrays send raw acoustic data over connecting cables to shore sites or, in the future, to the LCS. The following subsections discuss ASW sensors in more detail.

D.2.1 Surface Combatant ASW Sensors
  • SQS-53 Series Hull-mounted Sonar: The current active/passive low-frequency sonar on the bow of CG-47 and DDG-51 class ships.

  • SQS-56 Active/Passive Hull-mounted Sonar: The current active/passive medium-frequency sonar on the bow of FFG-7 class ships.

  • SQR-19 Tactical Towed Array System (TACTAS): The legacy passive acoustic towed array on CG-47, FFG-7, and some DDG-51.

  • Multi-Function Towed Array (MFTA): The current (just entering the fleet on DDG-51 and CG-47 classes) low- and mid-frequency bistatic/multistatic towed array receiver capability potentially used in conjunction with various active acoustic sources (e.g., SQS-53, airborne low-frequency sonar [ALFS] dipping sonar). MFTA is also capable of conventional passive acoustics for the detection of submarines or torpedoes.

  • Littoral Combat Ship (LCS)-related ASW sensors: LCS will primarily rely on off-board sensors for ASW. These could include sensors employed by the SH-60R helicopter (e.g., ALFS, various sonobuoys, MAD), sensors employed by various off-board vehicles (e.g., unmanned surface vehicle, vertical takeoff unmanned airborne vehicle, unmanned undersea vehicle), or sensors deployed by LCS itself (e.g., automatic dependent surveillance [ADS], extended echo ranging


Further information is available at <http://www.boeing.com/phantom/advsystems/scaneagle.html and http://www.isrjournal.com/story.php?F=588644>. Accessed January 26, 2006.

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