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T-AGOS 1 Stalwart
Ocean Surveillance Ship

Ocean surveillance ships have a single mission to gather underwater acoustical data. The T-AGOS ships operate to support the anti-submarine warfare mission of the Commanders in chief of the Atlantic and Pacific Fleets. The ships are operated and maintained by civilian contractors.

During the Cold War, ocean surveillance ships prowled the world's oceans searching for Soviet Navy submarines. Today, with the Cold War having thawed and the Soviet Union dismantled, these ships, operated by the Military Sealift Command and designated T-AGOS, now gather underwater acoustical data in support of U.S. Navy tactical operations in littoral waters. Their data is collected using the Surveillance Towed Array Sensor System (SURTASS) comprised of listening devices and electronic equipment that transmit the acoustic data via satellite to shore for analysis.

The ships first went to sea in the early 1980's, prowling the world's oceans in search of nuclear powered submarines belonging to the former Soviet Union. The SURTASS ships, with the hull designation T-AGOS, provided the world wide ocean surveillance, the US Navy required, with remarkable reliability. Today, they still patrol the vast oceans and also support fleet battle groups operating in littoral regions with the mission to gather underwater acoustical data. The T-AGOS ships operate in support of the anti-submarine warfare mission of the Commanders in chief of the Atlantic and Pacific Fleets.

T-AGOS ships are operated by the Military Sealift Command and are under the administrative command of Commander, Undersea Surveillance. They are deployed under the Operational Control (OPCON) of the Theater ASW Commanders, CTF 84 and CTF 12. Civilian technicians who operate and maintain the mission equipment man the SURTASS Operations Center (SOC), the nerve center of the ship. When operating with tactical forces, military detachments are embarked for onboard analysis and direct reporting to fleet units. A SURTASS mission consists of 60 days on station while towing an array of hydrophones that collect acoustic data.

The ships are homeported at Little Creek and Saint Helena's Annex, Virginia; Anacortes, Washington; and Port Hueneme, California. When operating independently as in a deep ocean surveillance mission, acoustic data is transmitted to shore via satellite for analysis and reporting. SURTASS ships have proudly operated throughout the world supporting the Undersea Warfare/Anti-Submarine-Warfare mission of all five numbered fleets of the U.S. Navy.

The ship is designed to tow an array of underwater listening devices to collect acoustical data. The ship also carries electronic equipment to process and transmit that data via satellite to shore stations for evaluation. The ship, the listening devices and electronic equipment are all part of a system called the Surveillance Towed Array System, or SURTASS. SURTASS is a linear array of 8575 ft deployed on a 6000 ft tow cable and neutrally buoyant. The array can operate at depths between 500 and 1500 ft. Information from the array is relayed via WSC-6 (SHF) SATCOM link to shore. SURTASS patrols are of 60-90 days duration [which even with passive tank stabilisation is a long time to wallow around at 3 kts].

The Monohull T-AGOS design, is based on the T-ATF Fleet Tug hull configuration. Various design features are incorporated to satisfy the SURTASS operating requirements and mission profile. The design is based on a mission duration of up to 90 days of towing operation at 3 knots, with a maximum sustained speed in transit of 11 knots. The ship's complement of 30 includes the SURTASS technical personnel, known as the (shipboard Operation and Maintenance (O&M) crew). In mission operations a total of 24 shipboard personnel, 18 ship's crew and 5 SURTASS O&M crew, is typical.

This programm was completed after several rocky years stemming from the financial difficulties of Tacoma Boatbuilding Co. which built the first eight ships but initially was unable to complete T-AGOS 9-12 before filing for bankruptcy. Halter Marine built T-AGOS 13-18. The STALWART class T-AGOS vessels, T-AGOS 1 through T-AGOS 18, were originally admeasured as less than 1600 gross tons and later re-admeasured as over 1600 gross tons.

The USNS BOLD (T-AGOS 12), the 12th ship of the Stalwart class, completed the 500th SURTASS mission, and a ceremony commemorating the milestone mission was conducted at U. S. Naval Station; Rota, Spain July 12, 2000 as BOLD made a portcall there following her historic patrol. Five hundred missions equate to over four million nautical miles of at-sea surveillance operations. Notable events included exchange of photo taking and greetings with helicopters, fixed wing aircraft and intelligence gathering vessels of the Soviet Union, at sea Medical Evacuations (MEDEVACS) for seriously ill or injured SURTASS ship crew members, sharks attacking the acoustic array, various periscope sightings, and iceberg evasion. Based on the number of BZ (Navy abbreviation for Well Done) messages received over the years, T-AGOS ships have time and time again proven their value both as strategic and tactical assets.

The SURTASS/Twin-Line Array Engineering Development Model was installed on the USNS Assertive (T-AGOS-9), and the first production model was installed on the USNS Bold (T- AGOS-12). Funding for six additional twin-line arrays was provided in the FY 2000 FYDP.

The Space and Naval Warfare Systems Command (SPAWAR), San Diego, manages the SURTASS program and contracts with the Raytheon Compny to operate and maintain the SURTASS equipment on T-AGOS ships. By early 1999 SPAWAR was inserting the second generation of commercial-off-the-shelf (COTS) equipment into the SURTASS baseline. USNS BOLD became the first T-AGOS ship to complete this upgrade, which added a Twin-Line towed array, a surface ship tracking capability, and included a COTS processing refresh and communications upgrade. The upgrades will significantly enhance the ships and SURTASS anti-submarine warfare capabilities in the high surface clutter environments of shallow water operations.

When deployed with a military detachment that augments its predominantly civilian crew for on-board analysis and direct contact reporting, the ships provide the fleet with a highly effective ocean surveillance capability that supports both deep ocean and shallow water warfare missions.

Three of the ships have been converted for utilization in the drug interdiction campaign. Four are involved in Atlantic undersea surveillance, and one in similar operations in the Pacific.One is involved in research and development activity in the Pacific, and another is in a reduced operating status. Six others of the class have been transferred to other government agencies including two to the Coast Guard. All 16 could be converted back to SURTASS operations if required.

The Counter-Drug Operations T-AGOS ships -- USNS Stalwart (TAGOS 1), USNS Indomitable (TAGOS 7) and USNS Capable (TAGOS 16) -- are monohull ocean surveillance ships originally designed to gather underwater acoustical data. The three Stalwart class ships have been modified for a drug interdiction mission. The underwater acoustic array was removed, and an air search radar, integrated display system, sophisticated communications suite and other special mission equipment were installed to detect and monitor suspected drug traffickers. Stalwart, along with two sister ships, was deactivated in the early 1990s when the end of the Cold War signaled a reduced submarine threat from the former Soviet Union. However, the Atlantic Commander decided to convert the three ships for a new mission - finding narcotics traffickers. They now support the Joint Interagency Task Force, East.

Joint Task Force Surveillance (JTFS) System is designed to correlate and utilize multi-sensor information including, acoustic, electronic intelligence (ELINT), radar and area contact information to develop a complete picture of a surveillance area. The system utilizes both on board sensors and externally provided information for cueing and/or correlating sensor data into an integrated surveillance picture. The use of automatically generated acoustic and ELINT parameters, for semi-automatically tracking and confirming an established, correlated acoustic/ELINT track and an automatically generated radar track is the unique process of the JTFS System. Data from the acoustic segment are marked for local reporting by the operator and are automatically sent to a correlator/tracker. The received ELINT data and the radar tracker data are automatically sent to the correlator/tracker. The Correlator/Tracker operator views all the sensor inputs and determines with the Correlator/Tracker tools which of the data elements correlate and merges these parameters into a single smooth externally reportable contact track. This external report could be sent via GCCS-M 3.1.1 or Link 11 depending on the forces being supported. JTFS is (proof of concept) installation on two T-AGOS ships being evaluated by fleet operators.

The Coast Guard has leased two TAGOS class ships from the Navy, USNS PERSISTENT (East Coast) and USNS VINDICATOR (West Coast). Both ships have been outfitted with a Mission Operation Center (MOC) and two Deployable Pursuit Boats (DPB's). The ships crew (19) is made up of members of the Military Sealift Command (Maersk Line Limited) and two civilian contract electronics technicians. The ships crew is responsible for virtually everything outside the MOC and DPB's. TACLET provides 34 members divided into two teams of 17. Of the 17 TACLET members 4 are designated MOC watchstanders. The MOC is outfitted with a CIC/COMMS suite comparable to a 378. What makes this unique and challenging is the fact that only one person is on watch at a time. The four watchstanders per team are comprised of an RD1 (MOC supervisor), TC2, QM2., and RD3. They are responsible for 2 independent GCCS-M systems, link 11 interface, surface search radar, air search radar (AN/SPS-49), IFF with Doctrine Processor, HF, UHF, and VHF communications. Record message traffic on NAVMAX terminal (CUTIX), Navy Order Wire (NOW) terminal for SATRATT, STATNET, SAS Controller, Communications patching and troubleshooting, and a FLIR camera system. The contract technicians maintain all of the electronic equipment with the exception of the 73 radar (one in the MOC and two on the bridge). The assigned Coast Guard ET is responsible for the 73 radar and all electronic equipment on the DPB's.

On 16 August 2000 the Military Sealift Command awarded a three-year contract for more than $108 million to Maersk Line, Limited of Norfolk, VA, to operate and maintain all 14 MSC-owned Auxiliary General Ocean Surveillance T-AGOS class ships. The fourteen ships support four Department of Defense programs: the Navy's Surveillance Towed Array Sensor System (SURTASS) operations; Navy, Atlantic Fleet and U.S. Coast Guard counter drug initiatives; and the Air Force Electronic Systems Command's radar missile tracking system.

Office of NOAA Corps Operations has taken 7 older and inefficient ships out of service and brought one new efficient oceanographic ship and two nearly new Navy T-AGOS ships into service. For deep ocean research, the converted Navy T-AGOS ship KA'IMIMOANA (Ocean Seeker) is specially equipped to deploy and recover a series of deep sea buoy arrays that collect information on climate change activities. KAIMIMOANA is homeported in Hawaii and is specially configured for, and dedicated to, servicing the Thermal Ocean Array [TAO] buoys monitoring El Nio in the tropical Pacific. KA'IMIMOANA was originally built as the U.S. Naval Ship TITAN (T-AGOS 15) in 1989 by Halter Marine in Moss Point, Mississippi. TITAN was operated by the Military Sealift Command as an Ocean Surveillance Ship until her transfer to NOAA on August 31, 1993. Conversion to her present configuration began in May, 1995 at Maritime Contractors, Inc Shipyard in Bellingham, Washington, and she was redelivered to NOAA as KA'IMIMOANA in April 1996. KA'IMIMOANA is now fully operational, ready to support NOAA's oceanographic and climate research missions in the Pacific.

In FY 1996, RTS commissioned the Kwajalein Mobile Range Safety System (KMRSS) . The KMRSS is hosted on the T-AGOS class USNS Worthy. The superstructure of the Worthy was modified to support redundant telemetry antennas. Existing instrumentation compartments provide housing for the TM equipment along with decommutation equipment necessary to provide Flight Safety officers with visual presentation from which to assess missile performance. Each telemetry antenna supports both the S-band receiving gear and the UHF Flight Termination System transmitting antenna. The Worthy has some limited capability to support billeting for operations at remote launch sites. The USNS Worthy, a T-AGOS class ship, has been commissioned to serve as a mobile instrumentation platform at RTS. The Kwajalein Mobile Range Safety System is installed on the Worthy to support TMD related remote site launch activities. The Worthy also provides logistical and other instrumentation support for remote site operations.

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Page last modified: 07-07-2011 12:58:30 ZULU