USNS Silas Bent (T-AGS 26) on 7 July 1965.
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Class: SILAS BENT (T-AGS 26)
Design: SCB Project Nos. 226 and 728.67 (medium type)
Displacement (tons): 1,935 light, 2,420 to 2,580 full
Dimensions (feet): 285' oa (287' in AGS 33-34), 265' wl x 48' e/wl x 15'to 16' max nav, 17’ lim
Armament: none
Accommodations: 44 crew, 34 scientists
Speed (kts.): 12
Propulsion (HP): 3,440 (AGS 26), 3,600 (others)
Machinery: Diesel electric, 1 screw
Construction:
| AGS | Name | Ord | Builder | Keel | Launch | Svc |
| 26 | SILAS BENT | 23 May 1963 | Am. SB, Lorain | 2 Mar 1964 | 16 May 1964 | 23 Jul 1965 |
| 27 | KANE | 5 Feb 1964 | Christy | 19 Dec 1964 | 20 Nov 1965 | 19 May 1967 |
| 33 | WILKES | 27 Sep 1967 | Defoe, Bay City | 18 Jul 1968 | 31 Jul 1969 | 28 Jun 1971 |
| 34 | WYMAN | 27 Sep 1967 | Defoe, Bay City | 18 Jul 1968 | 30 Oct 1969 | 3 Nov 1971 |
Disposition:
| AGS | Name | T | Inact | Strike | Disposal | Fate | MA Sale |
| 26 | SILAS BENT | T | 28 Oct 1999 | 28 Oct 1999 | 28 Oct 1999 | Trf | -- |
| 27 | KANE | T | 31 Mar 2001 | 14 Mar 2001 | 14 Mar 2001 | Trf | -- |
| 33 | WILKES | T | 8 Sep 1995 | 1995? | 29 Sep 1995 | Trf | -- |
| 34 | WYMAN | T | 10 Mar 1997 | 3 May 1999 | 28 Jul 2001 | MA/T | 28 Jan 2014 |
Class Notes:
On 29 July 1960 three new construction types of ships for ocean surveys and oceanographic research were under consideration: a 500 ton AGOR (SCB 213, dropped by the SCB after its OPNAV sponsors concluded that it did not offer sufficient ocenographic capability for the cost), a 1,200 ton AGS (which was found to differ only in minor fashion from the Project 185 AGOR and ultimately became AGS 25), and a 2,000 ton AGS (which measured 250' x 43' and ultimately became AGS 26). In March 1961 the Ship Characteristics Board staff began work on the first preliminary characteristics for what was now a 3,000 ton AGS in the FY 1963 building program. These characteristics were to be identical to the approved characteristics for SCB 214 (AGS 25) with the deletion of the statement that she was to be designed as a follow ship to SCB Project 185, recalculation of hull dimensions, addition of a meterological facility, and an increase in speed to 15 knots sustained. The ship was to have a single screw diesel electric plant with an auxiliary gas turbine generator and a bow propulsion unit as in SCB 214. The merchant crew was to consist of 9 officers and 18 enlisted plus 20 scientists, increased by 5 scientists and 1 enlisted from SCB 214. Area for scientific spaces was to be increased by 20% over SCB 214. On 6 April 1961 a working level meeting of the Ship Characteristics Board reviewed staff proposed characteristics for this ship, now designated SCB Project No. 226. She was functionally very similar to the Project 214 AGS (AGS 25) in the FY 1962 program but with significant differences. The primary difference was the increased size to provide improved seaworthiness and increased facilities for research and civilian work. Other differences included adding auxiliary propulsion equipment for quiet operation at slow speed and batteries for silent operation (offset by removing the requirement for silencing of the main propulsion plant), increasing sustained speed from 12 to 15 knots, and increasing accommodations for scientific personnel from 15 to 20. (There was also a crew of 27 merchant mariners.) The initial approved characteristics for a 2,250-ton Surveying Ship (AGS), SCB Project No. 226, were promulgated on 11 July 1961 as applicable to the FY 1963 ship.
A memo on the SCB 226 design dated 28 August 1961 prepared in the Preliminary Design section of BUSHIPS began by reviewing the development of the 1,400-ton AGOR 3 design. The memo stated that it appeared to the Bureau, and the Bureau thought to the oceanographic community as a whole, that this design was an excellent solution to the oceanographer's problem. The Bureau was thus somewhat surprised that a demand for a new design of any kind appeared quietly in the FY 1962 program. Acknowledging that science moves constantly towards new horizons, the Bureau participated in the development of characteristics for the new design, SCB 226, under circumstances in which both oceanographic and hydrographic interests were given full opportunity to state their specific demands, of which all the significant ones were granted. The Bureau worked in close liaison with the Hydrographic Office to make certain that the design included adequate laboratory space, resulting in a 90% increase in laboratory areas over AGOR 3 largely in anticipation of future growth. (The increase could not have been justified by the instrumentation and hardware then available for oceanographic service.) The design also incorporated increases in scientific accommodations, habitability, speed, weight reservations, and winch requirements, and added new scientific facilities. Following the inclusion of larger growth margins than would be used in a normal design the Bureau ended up recommending a 2,250-ton ship.
The firm of M. Rosenblatt & Son, Inc., of New York was made design agent for SCB 226, with final contract plans and specifications due on 14 September 1962. The contract was concluded on the basis of a design for a 255-foot, 2,250 ton displacement vessel with a total complement of 54 men including 20 scientists. On 31 August 1961 the Hydrographer of the Navy wrote to the Chief of BUSHIPS that his staff had concluded that the AGS (SCB 226) as presently planned would not be able to satisfy his office's requirements for an "ocean-wide" survey ship. The major discrepancies were insufficient laboratory and scientific stowage apace, insufficient scientific accommodations, and inadequate wardroom and crew mess-lounge facilities. The scientific accommodations of 20 scientists and four technicians needed to be increased to 30 scientists and four technicians according to new analysis of the increasing data collection/survey tasks required by TENOC and the national oceanographic program. MSTS and BUSHIPS determined that this required a corresponding increase in MSTS personnel to 41 men for a total complement of 75 men, plus an increase in the size of the ship from 255' oa x 47' for 2,250 tons to 280' oa x 48' for 2,550 tons and a cost increase of $1 million per ship. Rosenblatt was informed on 23 October 1961 that no decision had been reached within BUSHIPS regarding a possible change in the vesel's major characteristics. These modifications were included in a change to the 11 July 1961 characteristics dated 26 December 1961. A SCB memo of 30 November 1961 explained that the basic reason for the increased requirements was that in the original concept this type ship was to conduct underway or stationary surveys in separate ships or in separate cruises of the same ship with different personnel and instrumentation, while the current concept was to conduct combined operations which required more scientific personnel and more instrumentation but increased the work accomplished in a more efficient manner. On 4 December 1961 Rosenblatt was directed to proveed with the design of a vessel 280 feet long, 2,550 tons displacement, with a complement of 75 men and other characteristics changed accordingly. In a progress review on 1 February 1962 of Rosenblatt's work it was noted that, on a square foot per man basis of endurance stores, the Rosenblatt design approached the ELTANIN conversion quite closely and was far in excess of the BUSHIPS initial feasibility study. As of February 1962 the design measured 285'7" oa, 265'0" wl, 261'0" pp (to the rudder stock) x 48'0" beam x 15'0" mean and 16'1" aft at full load for a total full load displacement of 2,596 tons. The designed maximum sustained speed was 15.0 knots at 3,400 SHP and trial speed was 15.9 knots. The design provided for 12 officers, 4 CPOs, 25 enlisted and 34 scientists including 4 transients for a total of 75 men.
A brochure dated 15 August 1962 describing the preliminary design of SCB 226 stated that it was the second special type oceanographic research ship intended for US Navy use and added that it would be a larger ship than the first, SCB Project 185, and would be capable of carrying out both hydrographic surveys and oceanographic research studies. The characteristics for Project 226 were updated for FY 1964 on 12 April 1963, and were then updated for a Medium Surveying Ship (T-AGS), SCB Project No. 728.67, on 29 November 1966 with a final change on 10 September 1970. This FY 1967 update, promulgated as OPNAVINST 9010.271, stated that it was applicable to the mapping and charting-oriented medium surveying ship in the FY 1967 Shipbuilding and Conversion Program. Approved characteristics for a Medium Surveying Ship (T-AGS), SCB Project No. 725.67, were also promulgated on 29 November 1966 with a final change on 9 November 1970. This document, promulgated as OPNAVINST 9010.270, was stated to be applicable to the oceanographic-oriented medium surveying ship in the FY 1967 Program. The publicly-released brochure for the final version of the FY 1967 program, dated June 1967, showed two AGS's of SCB Project No. 728.67 and described them as the same type as the medium surveying ships authorized and funded in FY 1964 and the third and fourth ships of that class. Project 725.67 was either not proceeded with or was more likely merged into Project 728.67.
On 15 February 1964 SECNAV assigned the name SILAS BENT to AGOR 9 (q.v.). On 12 March 1964 he cancelled this assignment and reassigned the name SILAS BENT to AGS 26. On 16 July 1968 SECNAV assigned the name WILKES to AGS-33, having cancelled it for the obsolete DD 441. The first three ships were assigned to support the ASW oceanographic survey program with two ships in the Atlantic and one in the Pacific. In addition to geophysical data these ships collected acoustic and water mass data and performed special sea-floor studies. SILAS BENT originally had a prototype "Shipboard Survey System" based on a standard Navy AN/UYK computer while KANE initially had the Hydrographic Data Acquisition System (HYDAS), which collected and processed digital data depicting the configuration of the ocean floor as well as the earth's crust below it. In 1971 SILAS BENT, KANE and WILKES received the Oceanographic Data Acquisition System (ODAS), which was essentially a HYDAS system that was doubled in size to also collect and process digital temperature and salinity measurements. WYMAN was first equipped with HYDAS but after being designated to replace USNS SGT GEORGE D KEATHLEY (T-AGS-35) for gravity, magnetic and bathymetric surveys was re-equipped with a new processing system, replacing HYDAS, called the Bathymetric Survey System (BASS) and a new narrow beam swath array, replacing a single beam system, called the Bottom Topography Survey Subsystem (BOTOSS). These allowed her to perform similar data mapping functions to those performed by USNS H H HESS (T-AGS 38) along with the earlier BOWDITCH and DUTTON (T-AGS 21-22) to support the Trident Fleet Ballistic Missile Submarine force. Her initial BOTOSS hull mounting was subject to air bubble interference and in November 1974 she went to a a West Coast yard to receive a new arrangement on a fairing and foil mounted on the keel, after which she returned to the Atlantic in August 1975 for operations.
Ship Notes:
| AGS | Name | MA | Notes |
| 26 | SILAS BENT | FY 1963. Delivered at NSY Boston Jul 1965. To MSTS 24 Sep 1965. To Turkey as ÇEŞME 28 Oct 1999. | |
| 27 | KANE | FY 1964. Delivered at NSY Boston 19 May 1967. To MSTS 13 Jun 1967. To Turkey as ÇANDARLI 14 Mar 2001. | |
| 33 | WILKES | FY 1967. To MSC from Com 1 16 Jul 1971. To Tunisia as KHEIREDDINE 29 Sep 1995. | |
| 34 | WYMAN | FY 1967. Keel date also reported as 12 Aug 1968. Accepted by MSC at NSY Boston 19 Nov 1971. To MA custody 26 Mar 2001. Departed SBRF 4 Mar 2014. BU complete 1 Oct 2014. |
Page Notes:
Compiled: 19 Oct 2021
© Stephen S. Roberts, 2021
Special sources: NARA: RG 19 Entry P 62 Box 75, RG 19 Entry P 26 Box 18, RG 19 Entry P 39 Box 25; Office of Science and Technology, The Federal Ocean Program (President's Annual Report to Congress), Washington, D.C.: Government Printing Office, April 1972, pp. 65–72.