Quick Links Menu.

USS Neosho (AO 143).

USS Neosho (AO 143).
Click on this photograph for links to larger images of this class.

Class: NEOSHO (AO 143)
Design: SCB Project No. 82
Displacement (tons): 11,600 light, 38,000 full
Dimensions (feet): 655' oa, 640' wl x 86' e/wl x 35' max nav
Original Armament: 2-5"/38S, 6-3"/50T, plus 6-20mmT in 143-45 and 148
Later Armaments: (143, 144: 1957) 1-5"/38S, 6-3"/50T except 4-3"/50T in 144; (all less 144: 1959-61) 6-3"50T; (144: 1961, 143: 1965, 147: 1969, 145-146 and 148: 1976) 4-3"/50T; (148: 1979) 2-3"/50T; (MSC 1976-80) none
Accommodations: 21 officers, 303 enlisted
Speed (kts.): 20
Propulsion (HP): 28,000
Machinery: Geared steam turbines, 2 boilers (600psi/675deg), 2 screws

143NEOSHO24 Aug 1951Bethlehem, Quincy2 Sep 195210 Nov 195324 Sep 1954
144MISSISSINEWA28 Jan 1952NYSB4 May 195312 Jun 195418 Jan 1955
145HASSAYAMPA28 Feb 1952NYSB13 Jul 195312 Sep 195419 Apr 1955
146KAWISHIWI28 Jan 1952NYSB5 Oct 195311 Dec 19546 Jul 1955
147TRUCKEE28 Feb 1952NYSB21 Dec 195310 Mar 195523 Nov 1955
148PONCHATULA28 Jan 1952NYSB1 Mar 19549 Jul 195512 Jan 1956

AONameTDecommStrikeDisposalFateMA Sale/Depart
143NEOSHOTr10 Aug 199216 Feb 19941 May 1999MA/T18 Dec 2004
144MISSISSINEWATr30 Jul 199116 Feb 19941 May 1999MA/T30 Jan 2007/D
145HASSAYAMPATr2 Oct 199116 Feb 19941 May 1999MA/T7 May 2014
146KAWISHIWITr31 Jul 19927 Nov 19941 May 1999MA/T1 May 2014
147TRUCKEETr21 Oct 199118 Jul 19941 May 1999MA/T6 Aug 2008/D
148PONCHATULATr1 Apr 199231 Aug 19921 May 1999MA/T28 Apr 2014

Class Notes:
Increased demand for oil for international postwar reconstruction and domestic U.S. economic growth produced an acute worldwide tanker shortage in the winter of 1947-48. As part of its response the American oil industry developed a type of tanker larger than the ubiquitous World War T2 that fell into the Maritime Commission's T5 category (waterline length between 600 and 650 feet) and undertook a program to build 64 of these ships by the end of 1950. During 1948 the Maritime Commission developed a national defense variant of the T5 tanker, design T5-S-DU1, with a speed of 18.5 knots instead of the 16 knots of the various commercial designs. The Commission offered funding for inclusion of the increased speed in five privately built ships in FY 1949 and ten in FY 1950, but there were no takers. (The characteristics of the T5-S-DU1 design were 630’ waterline length x 83’ beam, 20,000 shp for 18.5 knots, 24,000 deadweight tons, 217,500 barrels of cargo, and a crew of 56.)

As of 18 November 1950 no new fleet oilers (AO) were scheduled for construction for the Navy in FY 1951-55. However during the Korean War the Navy struggled to keep the ships of Carrier Task Force 77 supplied at sea while on station in the Sea of Japan. The naval forces employed in Korea were smaller than those used in World War II but in some ways the operations were far more intensive -- aircraft sortie rates and the amount of ordnance expended were both greater than in the longer, global war. Replenishments of Task Force 77 took excessive time and could be limited by bad weather. While the Navy had more than enough T3-type tankers, these lacked the speed, cargo capacity, and transfer rates needed to support the intensive air operations being conducted by Task Force 77. On 29 December 1950 CNO recommended a revised building program for FY 1952 that added 12 fleet oilers, though with a fairly low priority. By 2 March 1951 it was intended to assign four of these to Bethlehem Steel Co., Quincy, Mass., four to New York Shipbuilding Corp., Camden, N.J., and three to Sun Shipbuilding Co., Chester, Pa., with one unaccounted for. They were planned for completion during 1954. These assignments were deferred in late April 1951 until the budget situation could be clarified. In a new list of assignments dated 2 July 1951 two were earmarked for Bethlehem Quincy (which by then was producing the preliminary and contract designs for the ships) and four were to be awarded by competitive negotiations, suggesting that the other six had been deleted for budget reasons.

In the meantime the Ship Characteristics Board began design work on a new fleet oiler in January 1951. The Maritime Commission T5-S-DU1 design with a cubic capacity with tanks 98% full of about 213,000 barrels provided a starting point, but the Navy now wanted a 20 knot speed with a speed of at least 15 knots during replenishments. The SCB staff issued first preliminary characteristics for its Shipbuilding Project No. 82 on 31 January 1951, stating that the new construction fleet oiler should have a cargo capacity approximately double that of the present types. The ship should have good maneuverability and rapid cargo discharge capacities using the most modern approved transfer-at-sea gear and replenishment techniques. She must be capable of maintaining formation speed of at least 15 knots while discharging cargo at maximum rate to ships alongside. A total petroleum products cargo space for approximately 190,000 barrels with additional bunker fuel capacity of 13,000 barrels was required. A displacement of 33,000 deadweight tons and dimensions of 670' x 85' x 32' were specified. Cargo space was to be allocated with 69% for black oil, 28% for two types of avgas, and 3% for diesel. In addition to eight fuel transfer stations the ship was to have the capability to operate two stores transfer rigs amidships, one on each side, to accomplish emergency stores and personnel transfers. A cargo deck (similar to that in the AO 106 class) was to be provided, located high above the main deck for dryness. An armament was specified of two 5"/38 single mounts, six 3"/50 twin mounts, and six 20mm twin machine guns. Speed was to be 20 knots trial and 17 knots sustained, both at full load. Propulsion was by a single screw. No aviation facilities were specified. Accommodations were to be provided for 20 officers and 300 enlisted. No flag accommodations were required.

Second preliminary characteristics for SCB 82 dated 9 February 1951 were prepared in a working meeting on 8 February 1951 and circulated on 19 February 1951. The earlier requirements were modified to state that the new construction fleet oiler should have increased cargo capacity over that of the present AO types and have total petroleum products cargo space for approximately 200,000 barrels. Displacement and dimensions were no longer specified. Other specifications were unchanged except that a twin screw design was now desired with both engines in a single machinery space. On 13 February 1951 BUSHIPS notified Navy officials in Quincy, Mass, that it intended to place a contract with the Bethlehem Steel Co. yard there, a recognized expert in tanker design, to act as design agent for the class and prepare preliminary and contract designs and plans for completion by 1 August 1951. At the beginning of March OpNav stated that they wanted a tanker of the size of the T5, not larger, and realized that the cargo capacity might be as low as 150,000 barrels. Full load draft could be as great as 34' but 33' was preferred. (BUSHIPS reported on 7 May 1951 that to get a replenishment oiler with a cargo capacity of 207,600 barrels at a draft of 33', a waterline length of 731' (T7 size) and a full load displacement of 47,600 tons would be required.) Instructions for the Design Agent dated 8 March 1951 for a ship with a cargo capacity of about 155,000 barrels produced dimensions of 630' wl x 85' x 33' full load and a full load displacement of 35,000 tons. Although twin screws were specified, the Design Agent was asked to explore possible advantages of single screw propulsion. The contract with Bethlehem for the hull and machinery preliminary designs for the new AO was dated 30 March 1951.

On 10 May 1951 Bethlehem, Quincy, presented to BUSHIPS its preliminary design for a Navy fleet oiler (its Design PR-1750), accompanied by a photo of a model, to demonstrate the feasibility of the concept of the new AO. Dimensions were 655.0' oa, 635.0' wl, 617.5' pp x 86.0' beam x 33.0' for a total displacement of 35,750 tons. Bethlehem found that a slight increase from the BUSHIPS figures of 630.0' wl x 85.0' x 33.0' wl and 35,000 tons was needed to come closer to the desired deadweight corresponding to a capacity of 155,000 barrels. The Navy regarded the shortfall as acceptable and was willing to allow an increase of the draft to 35' (with a displacement of 38,250 tons and capacity of 163,000 barrels) because the hull scantlings were already designed for 35', provided that the resulting gain in cargo capacity was operationally necessary. Accommodations were provided for 22 officers and 300 enlisted men. The propelling machinery was based on 600 psig, 850 degree F steam conditions, twin screws with turbine and gears in one machinery space and boilers in a secondary machinery space. The machinery was designed to provide maximum efficiency at 17 knots, corresponding to a total power of 17,200 SHP. It was estimated that a maximum of 28,600 shp was needed for a trial speed of 20 knots, and at this power boilers, turbines, and condensers would be operating (as expected) beyond their peak efficiencies. Bethlehem found that the overall efficiency with twin screws was about equal to that with a single screw but that there were numerous other reasons to prefer twin screws. On 24 May 1951 the staff of the Ship Characteristics Board produced Second Preliminary Characteristics (revised) for Project No. 82 based on this recent work and submitted them for a determination [not found] by the Board on 4 June 1951 of the final characteristics for Project No. 82. BUSHIPS accepted Bethlehem's preliminary design work as complete on 8 August 1951, although on 28 August 1951 Bethlehem informed the David Taylor Model Basin that it had extended the load waterline at the stern by 5 feet to eliminate the former blunt waterline endings.

On 30 June 1951 Congress made funds available to undertake the shipbuilding and conversion program contained in the 1952 budget estimates. Between August 1951 and January 1952 the Navy contracted for six Project 82 ships, only one (AO 143) going to Bethlehem. (AO 145 and 147 were ordered from Ingalls on 28 January 1952 but that contract was cancelled on 28 February 1952 and they were reassigned on the same date to New York Shipbuilding, which already had a contract for the other three.) On 28 April 1952 CNO convened a special conference on mobile logistics support to study the problems encountered supporting Task Force 77, and the conferees found the design of the new oiler to be highly satisfactory. Approved characteristics for a new construction fleet oiler (AO), SCB Project No. 82, were promulgated on 20 May 1953 and updated on 18 April 1958.

On 4 September 1953 a draft FY 1955 program included one additional Project 82 AO, but the FY 1955 program as recommended by CNO to SECNAV on 9 January 1954 included no auxiliaries except for four YAGRs. As of 16 March 1954 a contract design for a repeat Project 82 AO for FY 1956 was due within BUSHIPS on 15 June 1955, and on 24 June 1954 BUSHIPS and BUORD provided cost estimates for the proposed FY 1956 program (approved by SECNAV on 27 September 1954) which included one Project 82 AO. However on 28 October 1954 BUSHIPS Code 516 noted that the procurement of a single ship would be costly and recommended slipping the ship to the draft FY 1957 program, which already included two similar AOs. On 11 September 1954 CNO included two Project 82 AOs in a list of high priority ships to be included in the FY 1957 program, and on 19 July 1955 CNO approved a FY 1957 program that included the two AOs, but SECNAV had them deleted on 5 October 1955 for cost reasons. Planning in 1956 for FY 1958 focused on a new AOR design (Project 175) instead of more AOs. Approved characteristics for a fleet oiler (AO), SCB Project No. 82A, which added flagship facilities were promulgated on 21 October 1957 with a single change on 12 November 1957 but no ships of this type were built. By 1957 attention had reverted from the AOR to the AO, and on 6 May 1957 the DCNO for Logistics recommended that the FY 1960 program include two Project 82 AOs "since merchant conversions had limitations in fleet employment and would be in demand for civilian use in an emergency. [The FY 1960 AOs] would be built under the present characteristics or revision thereof, possibly incorporating three or more boilers to permit underway boiler maintenance." The first formal proposal for the FY 1960 program included one Project 196 AOE, one Project 114 AE, and one Project 82 AO, but on 25 July 1958 the AE and AO were dropped in favor of a second AOE, saving $2 million and providing one of the fast replenishment ships in each ocean. (The two FY 1960 AOEs were later slipped to FY 1961 and FY 1963.) Two Project 82 AOs were dropped in early stages of planning for FY 1961. After all this effort, the only Project 82 oilers that the Navy got were the initial six FY 1952 ships.

A new design of fleet oiler (AO) was included in the tentative FY 1962 building program. The major change in the FY 1962 AO from SCB Projects No. 82 and 82A, as directed by OpNav on 13 April 1960, was the requirement for a sustained speed of 20 knots vice a trial speed of 20 knots and for three boilers instead of two. The magnitude of the changes caused the assignment of a new project number, SCB 217, and aroused concerns over cost. Final characteristics adopted at a working level meetins of the SCB on 20 September 1960 included a full load displacement of 38,296 tons, dimensions of 655' oa x 94' x 35' full load, a crew of 325 men, a cargo capacity of about 150,000 barrels, twin screws, an armament of four 3"/50 twin mounts, and a helicopter platform (added in September 1960). There were four fueling stations to port and two to starboard plus one stores transfer rig on each side. By September 1960 SCB 217 was no longer in the FY 1962 program, and design work on it soon ceased. A March 1961 draft of the FY 1963 program again included a new oiler (AO). Approved characteristics for an oiler (AO), SCB Project No. 217, were promulgated on 20 September 1961 without later changes. The ship was soon competing in budget planning with the AOR, causing the SCB to protest in October 1961 that the AO carried more NSFO (the fuel most needed by the fleet) than the AOR and was somewhat less expensive. The AOR along with jumboized World War II T3 oilers (AO 105 and 51 classes) ultimately prevailed in the FY 1963-1967 programs.

On 14 May 1959 a team from the Preliminary Design Branch of BUSHIPS (Code 421) visited AO 147 and AO 143 to get their crews' reactions to this relatively new AO type in connection with new design work then in progress (notably the AOE type). They learned that the AO 143 type ships had experienced no difficulty in replenishing operations in up to force 4 winds due to poor seakeeping or lack of stability and that roll stabilization features were unnecessary. The ships had, however, experienced major trouble with green water inundating the main deck and even the forecastle, smashing up and completely disrupting the deck load cargo of AVGAS drums and pressurized gas cylinders on the main deck and causing structural damage on the forecastle. The ships suggested that the main deck forward be enclosed. Visibility from the bridge was considered fine after the removal of the forward centerline-mounted 5" gun. The most serious criticisms related to the machinery plant. Opinion was unanimous that the ships were underpowered in backing, that the two boilers were insufficient, and that the ship service generators were inadequate to the extent that starting up the fire room forced draft blowers created a serious power drop on the line followed by a power surge that burned out lights and electronic components. The Executive Officer of NEOSHO summarized the general feeling concerning the machinery plant by called it "archaic." When shown the AOE design the officers of the two ships endorsed most of its features except the 40-foot draft, which they pointed out was too much for nearly all harbors on the U.S. East Coast, including Norfolk, to handle.

The armament of the class went through three major configuration changes. Originally the ships had a single 5"/38 enclosed mount at each end and six 3"/50 twin mounts, two abreast forward and four at the corners of the after superstructure. The first change was the removal of the 5"/38 mounts in 1959-61, leaving the ships otherwise unchanged with their six 3"/50 twin mounts. The second change was a modernization in 1965-76 in which the two 3"/50 twin mounts at the forward end of the after superstructure were displaced by a large new deckhouse and a small helicopter flight deck was added over the stern. The third change was the removal of all armament in 1976-80 when the ships were transferred to MSC. The main exception was AO 144, which received the flight deck and after deckhouse modernization as early as 1957, displacing the after 5"/38 gun and two after 3"/50 mounts but retaining the forward 5"/38 mount until around 1961.

The ships were built with eight replenishment stations, two forward of the bridge served by a cargo mast and six between the deckhouses served by three kingpost pairs. (There was also a second cargo mast amidships.) The two forward stations were for AVGAS and the three kingpost pairs supplied forward to aft black oil and diesel oil, black oil and JP-5, and AVGAS and JP-5. Aircraft carriers would replenish on the oiler's port side and escorts to starboard. Several improvements to fueling rigs were made in the late 1950s. Some AO 143 class ships received counterweight fueling stations (see AE 23-25 for this technology) in the late 1950s (generally in the after kingpost pair), a 7-inch light-weight collapsible hose replaced the World War II-vintage 6-inch rigid wire-reinforced hose, and fueling outriggers that tilted upwards and outwards from the tops of fueling kingposts were developed to replace the traditional fueling booms in supporting spanwires and hoses. Following completion of the tests of a ram-tensioned highline in VEGA (AF 59, q.v.) in April 1960 a complete prototype STREAM fueling station consisting of a ram tensioner, the new fueling outrigger, and the 7-inch hose was installed and tested on station four of HASSAYAMPA. Later, after eight years of testing, CNO in September 1965 approved a probe fueling system similar to that used in aircraft in-flight refueling in which a male fitting at the end of a 7-inch hose was "flown" down the spanwire on a trolly and mated with a swivel elbow on the receiving ship, sealing the connection and opening the refueling valve. The individual AO 143-class oilers subsequently had their fueling stations upgraded as operational requriements, overhaul schedules, and funding permitted, resulting in considerable variety. Ram tensioner systems seem to have been little used on these ships as they handled little cargo.

Ship Notes:
143NEOSHOFY 1952. Decomm. and to MSC 25 May 1978. To MA custody in JRRF 12 Aug 1992. Departed for breakers in Brownsville 9 Feb 2005, arrived 4 Mar 2005. BU completed 8 Nov 2005 by ISL.
144MISSISSINEWAFY 1952. Decomm. and to MSC 15 Nov 1976. To MA custody in JRRF 30 Jul 1991. Departed for breakers in Brownsville 30 Jan 2007. BU completed 11 Feb 2008 by ISL.
145HASSAYAMPAFY 1952. Decomm. and to MSC 17 Nov 1978. To MA custody in SBRF 14 Nov 1991. Departed 29 May 2014 for breakers (All Star Metals, Brownsville)
146KAWISHIWIFY 1952. Decomm. and to MSC 10 Oct 1979. To MA custody in JRRF 16 Sep 1992. Departed 12 Jun 2014 for breakers (Int’l. SBr Ltd.).
147TRUCKEEFY 1952. Decomm. and to MSC 30 Jan 1980. To MA custody in JRRF 12 Dec 1991. Departed 6 Aug 2008 for breakers (Bay Bridge Enterprises, Chesapeake, VA)
148PONCHATULAFY 1952. Decomm. and to MSC 5 Sep 1980. To MA custody in SBRF 2 Apr 1992. Departed 15 May 2014 for breakers (Int’l. SBr Ltd.).

Page Notes:
Compiled: 18 Sep 2021
© Stephen S. Roberts, 2021
Special sources: NARA: RG 19 Entry P 37 Box 51, RG 19 Entry P 26 Box 21 (SCB 217), RG 428 (Dept of the Navy) File FS/A1-1 Boxes 953-954; House hearings on the Independent Offices Appropriations Bill for 1950, part 2, 1 March 1949, pp. 539-548; New York Times 14 January 1949 p. 46 and 15 January 1949 p. 29; Thomas Wildenberg, Gray Steel and Black Oil (Annapolis, 1996); Marvin O. Miller, Designing the U.S. Navy's Underway Replenishment System, Naval Surface Warfare Center, Port Hueneme, Cal., 1996.