TAGS 26 Silas Bent
Survey Ship

The Silas Bent class of surveying ships were designed specifically for surveying operations. They have a bow propulsion unit for precise maneuverability and station keeping. The two similar units of the Wilkes class were recently discarded, with WilkesT-AGS-33 transfered to Tunisia on 29 September 1995. On 29 September 1999 Silas Bent was transferred to the government of Turkey, stricken from the Naval Oceanographic Office fleet to make room for the newer, more luxurious and state-of-the-art ships of the PATHFINDER class. USNS Elisha Kent Kane (T-AGS-27) was struck from the Naval Register on 14 March 2001 and sold under the Security Assistance Progrm to Turkey as of that date.

Survey Ships gather data which provides much of the military's information on the ocean environment. Oceanographic and hydrographic survey ships are used to study the world's oceans. The collected data helps to improve technology in undersea warfare and enemy ship detection. The oceanographic and hydrographic survey ships' multibeam, wide-angle precision sonar systems make it possible to continuously chart a broad strip of ocean floor. Military Sealift Command's Special Missions program supports worldwide oceanographic programs with ships which perform acoustical, biological, physical and geophysical surveys.

Dyn Marine Services of Virginia, Inc.(DMS) a unit of DynCorp, manages, operated, and maintained these ships for the Naval Oceanographic Office (NAVOCEANO) in Mississippi. DMS provided logistics, operations, engineering, and manning support for these US Naval oceanographic ships which were coordinated from the DMS Reston office. The ships were operated worldwide conducting ocean surveys at the direction of NAVOCEANO, with Commander Military Sealift Command (COMSC) acting as the Administrative Command.

SILAS BENT was the model for the first of the newest and best of the Navy's oceanographic fleet. In the mid-1960s, the Navy was well along in its TENOC (Ten Years of Oceanography) program to upgrade the oceanographic survey fleet. Prior to this, Naval oceanography and hydrography was conducted with aging warships, converted to oceanographic use. Among the ships employed in this duty were storied names such as converted minesweepers, USS REQUISITE (AGS-18), USS SHELDRAKE (AGS-19), USS PREVAIL (AGS-20) and USS TOWHEE (AGS-28); a former fleet tug, the USS SERANNO (AGS-24); and converted stores ships, USS TANNER (AGS-16) and USS MAURY (AGS-15), the big boys of hydrography and the first to bear these illustrious names. NAVO even had frequent use of a submarine, ARCHERFISH (AGSS-311).

These ships, except for ARCHERFISH, would all find their respective analogs in the new fleet. Other than the research-oriented AGORs, though, the centerpiece of the new ships was the SILAS BENT, a "medium class" oceanographic survey ship designed to replace the SAN PABLO (AGS-30) and USS REHOBOTH (AGS-50), both converted Navy seaplane tenders.

American Ship Building Company of Lorain, Ohio, started building the SILAS BENT in October 1963. She was delivered to the Navy in July 1965. Others of her class were soon to follow: USNS KANE (T-AGS-27), USNS WILKES (T-AGS-33) and USNS WYMAN (T-AGS-34), although WYMAN was not to serve as an oceanographic survey ship but rather as a bathymetry ship configured specifically to support OSP surveys.

When she first became operational, SILAS BENT was probably the most sophisticated ocean-ographic survey ship anywhere. For the first time, the heart - or rather brain - of the collection management system was a computer, which was virtually unheard of at that time. There were no computers being constructed specifically for oceanographic survey ships, so the first ones used aboard the BENT-class ships were "borrowed" from submarines. Her equipment suite employed a centrally integrated Central Data Recording System that managed the digital time and navigation-referenced logging of bathymetry, magnetics, gravity, and on-station digital logging of temperature, salinity pressure, sound speed and even ambient light. All these parameters were displayed in real-time for the operator at a central console. The system, built by Texas Instruments, was the "serial number one" version of what was called the Shipboard Survey System. The concept and technology were advanced, and although not all the expectations were immediately realized, the "envelope" was pushed and pushed very hard. The result was that advancements were much more quickly achieved and the future years made more productive sooner because of it.

SILAS BENT had many other measurement capabilities, too. She had installed systems for seismic profiling, coring and other bottom-sampling equipment, plankton-collection systems, underwater cameras including a photo lab, mechanical bathythermograph system (XBTs had not yet arrived) and a full chemical analysis suite for oxygen, salinity and nutrient determinations. To top it off, she had a meteorological laboratory, complete with weather balloons (with helium gas) and radiosonde equipment. This was, indeed, the Navy's first truly multi-purpose, multi-mission capable oceanographic survey ship.

A group designated the "AGS Task Team," led by Robert Seaton, had NAVO responsibility for the outfitting and the shakedown of the SILAS BENT and her sister ships. The members of the group picked, acquired and installed the equipment suite, including such minute items as the glassware required for the expected Knudsen titrations.

In the Cold War years, SILAS BENT most often sailed the deep, Soviet submarine-infested waters of the northern Pacific - from the U.S. west coast, east to Korea and from the Philippine Sea to the Bering Sea, though occasional forays were made to places such as Tahiti for special project work.

Occasionally, environmental support to naval forces included going places not often allowed in those days such as the Sea of Okhotsk, known to some as the "Lair of the Bear." She actually made several visits there, but perhaps the most memorable was in 1986 when she "followed" the USS NEW JERSEY (BB-62) task force into the Sea of "O." The powerful battleship force stayed there only a couple of days and garnered lots of press, but SILAS BENT slipped in by herself shortly thereafter and spent the next two months successfully surveying that important body of water - alone.

After the Cold War ended, the surveying focus shifted to littoral regions such as the Yellow Sea, the East and South China seas and the Sea of Japan. SILAS BENT was ordered to the Arabian Gulf when the Gulf War brought the Arabian Gulf to greater prominence. It was the first of the NAVO oceanographic survey ships in that area. SILAS BENT even journeyed as far west as the Mediterranean Sea during that time period for the turnover of crewing responsibilities from Military Sealift Command. Finally, in the late 1990s after going it alone in terms of oceanographic surveying for over 30 years, she was at last joined in the Western Pacific by other multipurpose oceanographic survey ships - first the USNS SUMNER (T-AGS-61) and later the USNS BOWDITCH (T-AGS-62).

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