|Ordered:||12 September 1940|
|Builder:||Bethlehem Sparrows Point Shipyard|
|Launched:||1 July 1941|
|Commissioned:||4 February 1942|
|Decommissioned:||20 December 1954|
|8 battle stars (World War II)|
|Fate:||Sold, 19 March 1982|
|Class and type:||Kennebec-class fleet replenishment oiler|
|Displacement:||6,013 long tons
(6,109 t) light
21,077 long tons (21,415 t) full
|Length:||501 ft 5 in (152.83 m)|
|Beam:||68 ft (21 m)|
|Draft:||30 ft 2 in (9.19 m)|
|Speed:||16.5 knots (30.6 km/h; 19.0 mph)|
|Capacity:||9 tanks, total 5,930,000 U.S. gallons (22,460,000 liters;
430m³ (15,200 cubic feet) dry cargo
|Armament:||• 1 × single 5"/38 caliber dual purpose
• 4 × single 3"/50 caliber dual purpose guns
• 4 × twin 40 mm Bofors
• 4 × twin 20 mm Oerlikons
USS Merrimack (AO-37) (ex-Caddo) was one of five Kennebec-class fleet oilers (also known as a type T2 tanker) built during World War II for service in the United States Navy, named after the Merrimack River.
The Merrimack was laid down as Caddo under Maritime Commission contract on 12 September 1940 by Bethlehem Steel Co., Sparrows Point, Maryland. It was launched on 1 July 1941 and acquired by the U.S. Navy from Socony-Vacuum Oil Company, New York City, on 31 December 1941. She was renamed Merrimack on 9 January 1942, and commissioned 4 February 1942, Capt. William E. Hilbert in command.
Assigned to the Atlantic Fleet, the new fleet oiler spent the next two and a half years steaming the Atlantic seaways carrying oil for Allied ships from Argentia, Newfoundland to Montevideo, Uruguay, and from ports along the U.S. east coast to staging areas in the British Isles and the Mediterranean. Her primary duty was fueling the escorts which protected Allied convoys from German U-boats.
Merrimack's most memorable crossing began on 23 October 1942 from Hampton Roads when she sailed with the Southern Attack Group of the Western Naval Task Force for "Operation Torch", the invasion of North Africa. Twice during the passage she refueled the ships of the task force. A heavy storm broke on 4 November threatening the landings, but Admiral H. Kent Hewitt kept to the original plan. Its mission was to capture the harbor at Safi, Morocco, to cut off French forces in southern Morocco, and to enable the landing of General Patton's tanks for operations against Casablanca.
For more than a year and a half after the landings in Morocco, Merrimack carried oil to support operations in North Africa, Sicily, Italy, and France. On her transatlantic voyages, besides oil, she carried passengers and a wide variety of equipment including PT boats, patrol craft, and aircraft. While steaming toward Casablanca on 22 June 1943, she joined minesweeper Pilot (AM-104) in rescuing 113 survivors from the Lot, a French oiler that had been torpedoed.
Merrimack departed Norfolk, Virginia, on 14 October 1944 for the Panama Canal and Ulithi, arriving on 1 December. Allied forces were retaking the Philippines and preparing for operations even closer to the Japanese home islands. Merrimack joined the 3rd Fleet's At-Sea Logistics Support Group to fuel the fast carrier task force. She began the new year supporting raids on Formosa on 3 and 4 January 1945. The U.S. carriers struck enemy airbases on Luzon, Philippines, on 6 and 7 January to help neutralize Japanese resistance to the invasion of that strategic island which began on the beaches of Lingayen Gulf on the 9th. Naval aircraft which she supported returned to Formosa on the 15th and hit targets along the China coast the following day. They again lashed out at Formosa on the 21st.
From 16 February through 2 March, Merrimack supported the ships covering the landings on Iwo Jima. During the fight for Okinawa, Merrimack alternated between fueling ships involved directly in the landings, and the aircraft carriers during raids to on the Japanese home islands.
After Okinawa was secured, the 3rd Fleet concentrated on operations against Japan itself. From 10 through 29 July 1945, Merrimack supported raids of overwhelming force on Japanese targets which hastened the end of the war. Following Japan's capitulation 15 August, Merrimack made several cruises between the west coast and the Far East bringing oil for ships supporting the occupation of Japan and operating along the coasts of China and Korea. She was assigned to Military Sea Transportation Service in October 1949, shortly before beginning pre-inactivation overhaul. Merrimack was decommissioned on 8 February 1950 and entered the Atlantic Reserve Fleet at Orange, Texas.
When North Korean forces invaded South Korea in 1950, Merrimack was recommissioned on 6 December 1950. Assigned to MSTS, the fleet oiler served the Atlantic Fleet, making periodic deployments to the Mediterranean until she was decommissioned on 20 December 1954, and entered the Pacific Reserve Fleet at San Diego. She was struck from the Navy List on 4 February 1959, transferred to the Maritime Administration, and placed in the National Defense Reserve Fleet at Beaumont, Texas. The Merrimack was disposed of by MARAD exchange on 19 March 1982. It was sold to Eckhardt & Co. GmbH, Hamburg, for scrapping, and delivered on 29 March 1982 at Beaumont.
Merrimack received eight battle stars for World War II service.