Kennebec-class oiler

Summary

The Kennebec-class oilers were sixteen United States Navy medium oilers built during World War II to three related designs at Bethlehem Sparrows Point Shipyard of Sparrows Point, Maryland and Sun Shipbuilding & Drydock Co. of Chester, Pennsylvania, all of which survived the war. One is still in commercial service as of 2022.

Niobrara underway in March 1943
Class overview
NameKennebec
Builders
Preceded byChicopee class
Succeeded bySuamico class
In commission1942–1970
Completed16
Active1 in commercial service as lake freighter
Lost1
Retired14
General characteristics
TypeMARAD T2
Tonnage15,910 DWT
Displacement21,077 tons
Length501 ft 8 in (152.9 m)
Beam68 ft (20.7 m)
Draft29 ft 8.5 in (9.1 m)
Depth37 ft (11.3 m)
Installed power12,000 shp (8,900 kW)
Propulsion
Speed16.5 knots (30.6 km/h; 19.0 mph)
Range8,000 nmi (15,000 km; 9,200 mi)
Capacity130,000 bbl (~18,000 t)
Complement214–247
Armament
General characteristics
Class and typeMattaponi-class oiler
TypeMARAD T2-A
Tonnage16,400 DWT
Displacement21,750 tons
Length520 ft (160 m)
Beam68 ft (21 m)
Draft29 ft 11.5 in (9.131 m)
Depth37 ft (11 m)
Installed power12,000 shp (8,900 kW)
Propulsion
Speed16.5 knots (30.6 km/h; 19.0 mph)
Range7,200 nmi (13,300 km; 8,300 mi)
Capacity133,000 bbl (~18,100 t)
General characteristics
Class and typeChiwawa-class oiler
TypeMARAD T3-S-A1
Tonnage16,543 DWT
Displacement21,077 tons
Length501 ft 7.75 in (152.9017 m)
Beam68 ft (21 m)
Draft29 ft 10.5 in (9.106 m)
Depth37 ft (11 m)
Installed power7,000 shp (5,200 kW)
Propulsion
Speed15.3 knots (28.3 km/h; 17.6 mph)
Range14,500 nmi (26,900 km; 16,700 mi)
Capacity133,800 bbl (~18,250 t)

All of the ships of the class initially were to be built for private companies, but the outset of World War II, the ships were transferred to the United States Maritime Commission and given new names. Later, when allocated to the U.S. Navy, they were renamed again.[1]

In some cases the Kennebec class is divided into three classes, the Kennebec class (AO-36 to AO-40, AO-48), the Mattaponi class (AO-41 to AO-44, AO-47) and the Chiwawa class (AO-68 to 72). The first two classes were of the T2 and T2-A designs, built by different shipbuilders, and the Chiwawas were of the T3-S-A1 design, mainly differing in having only a 7,000 shp (5,200 kW) engine and a top speed of 15.3 knots (28.3 km/h; 17.6 mph).

History edit

One of the first acts of the War Shipping Administration (WSA), established in February 1942, was to address the Navy's pressing need for oilers by requisitioning five tankers in service or under construction for civilian companies. Three of these were 16.5-knot (30.6 km/h; 19.0 mph) Type T2 "national defense tankers" designed by the Maritime Commission with potential militarization in mind and built by Bethlehem Steel for Socony-Vacuum Oil Co: the Corsicana, Caddo and Calusa. A month later the WSA requisitioned six more: Socony's Colina and Conastoga, together with four similar ships building at Sun Shipbuilding and Drydock for Keystone Tankships to an enlarged design, later called T2-A: Kalkay, Ellkay, Jorkay and Emkay. Corsicana was commissioned as USS Kennebec, becoming the lead ship of the class; Kalkay was renamed Mattaponi and gave that name to the T2-A subclass. In June the WSA moved to acquire the remaining member of each group, Aekay and Catawba.

The T2 design had itself been based on two ships built by Bethlehem Steel in 1938–39, Mobilfuel and Mobilube; the T2's principal difference was MarCom's inclusion of more powerful engines to produce the Navy's desired 16.5 knots. In the meantime MarCom under the State of Emergency had ordered thirteen duplicates of Mobilfuel for the merchant marine; the first of these were nearing completion in late 1942 when the Navy, still very short of oilers, requisitioned the first five starting with Samoset (ex-Mobiloil), renamed USS Chiwawa. Other than being limited to 15 knots, the Chiwawas were effectively identical to the Kennebecs, despite being assigned the confusing design code T3-S-A1.

All sixteen ships survived the war, but were decommissioned shortly afterwards in favor of the larger, faster Cimarron class. Kennebec, Merrimack, Kankakee, Mattaponi, Monongahela, Tappahannock, and Neches were recommissioned for the U.S. Navy after World War II. Mattaponi and Tappahanock were reactivated four times, serving until 1970.

Chiwawa (now Lee A. Tregurtha) is still in commercial service on the Great Lakes.[1] Neshanic (now American Victory) was sold for scrap and towed away to Turkey in 2018.

Ships of the class edit

Construction data
Name Hull no. Original name Commissioned Final decommission Fate
Kennebec AO-36 Corsicana 4 Feb 1942 1 Apr 1970 scrapped, 1982
Merrimack AO-37 Caddo 4 Feb 1942 29 Nov 1957 scrapped, 1982
Winooski AO-38 Calusa 27 Jan 1942 30 Apr 1946 sold commercial 1947, scrapped 1965
Kankakee AO-39 Colina 4 May 1942 27 Jun 1968 scrapped, 1976
Lackawanna AO-40 Conastoga 10 Ju 1942 14 Feb 1946 sold commercial 1947, scrapped 1967
Neosho AO-48 Catawba 16 Sep 1942 13 Dec 1945 sold commercial 1947, scrapped 1964
Construction data for Mattaponi subclass
Name Hull no. Original name Commissioned Final decommission Fate
Mattaponi AO-41 Kalkay 10 May 1942 30 Sep 1970 scrapped, 1973
Monongahela AO-42 Ellkay 11 Sep 1942 22 Aug 1957 scrapped, 1982
Tappahannock AO-43 Jorkay 22 Jun 1942 6 Mar 1970 scrapped, 1987
Patuxent AO-44 Emmkay 22 Oct 1942 21 Feb 1946 sold commercial 1947, scrapped 1985
Neches AO-47 Aekay 16 Sep 1942 1 Oct 1970 scrapped, 1973
Construction data for Chiwawa subclass
Name Hull no. Original name Commissioned Final decommission Fate
Chiwawa AO-68 Samoset, ex-Mobiloil 24 Dec 1942 6 May 1946 converted to Great Lakes ore carrier, 1961; still in service
Enoree AO-69 Sachem 23 Jan 1943 22 Oct 1957 scrapped, 1982
Escalante AO-70 Shabonee 30 Jan 1943 12 Dec 1945 sold commercial 1947, sunk 1960
Neshanic AO-71 Marquette 13 Mar 1943 19 Dec 1945 converted to laker; sold for scrap 2018
Niobrara AO-72 Citadel 20 Feb 1943 12 Nov 1957 scrapped 1982

Citations edit

  1. ^ a b Wharton, George. "Great Lakes Fleet Page Vessel Feature -- Lee A. Tregurtha". Great Lakes and Seaway Shipping. Archived from the original on 2007-10-17. Retrieved 2008-01-07.

References edit

This article incorporates text from the public domain Dictionary of American Naval Fighting Ships.
  • Wildenberg, Thomas (1996). Gray Steel and Black Oil: Fast Tankers and Replenishment at Sea in the U.S. Navy, 1912-1995. Annapolis, Maryland: Naval Institute Press. Retrieved 2009-04-28.