(AT-91: dp. 1,675 (f.); 1. 205'0"; b. 38'6"; dr. 15'4"
s. 16.25 k. (tl.); cpl. 85; a. 1 3", 2 40mm.; cl. Navajo)
Seneca (AT-9l) was laid down at Philadelphia, Pa. on 7 September 1942 by the Cramp Shipbuilding Co., launched on 2 February 1943; and commissioned at the Philadelphia Navy Yard on 30 April 1943, Lt. Herman B. Conrad commanding.
The tug completed fitting out and post-commissioning availability on 19 May and departed for trials, drills, and calibrations in the Delaware Bay. Three days later, she cleared the Delaware Capes and arrived at Norfolk, Va., for shakedown training. Seneca next stood out of Norfolk on 18 June, towing a target raft to Guantanamo Bay, Cuba. From 27 June until 7 July, she conducted antisubmarine warfare (ASW) training in the Guantanamo Bay operating area, then she headed for Trinidad to begin a tour of duty with the 4th Fleet.
For the next 21 months Seneca was assigned target towing, general rescue, an] salvage duties in the waters off the coast of Brazil. During one of her early rescue missions, Seneca captured two survivors of a German U-boat sunk by Allied ASW patrols. Seneca was redesignated ATF-91 on 15 May 1944. On 9 April 1945 she departed Bermuda for Norfolk with a dual tow. Upon arrival, she entered the Norfolk Navy Yard for overhaul. On 26 May 1945, she cleared Norfolk for a tour of duty at Port Everglades and Key West, Fla., with the Surface Group of the Antisubmarine Development Detachment. She towed targets and recovered torpedoes until her departure from Key West on 19 February 1946. Seneca towed a large floating crane to Philadelphia, arrived on the 26th, and later shifted to Norfolk for overhaul.
Following overhaul, Seneca commenced 25 years of operations out of Norfolk and Little Creek, Va. Her routine during this time consisted of target towing, rescue and salvage work, and ship towing, most often these were reserve ships moving from one berthing area to another or former Navy ships to be sunk as targets. Her sphere of operations consisted of the Atlantic seaboard, the Caribbean Sea, and the Gulf of Mexico. She spent much of her career in the Guantanamo Bay area and in the British West Indies, but also frequented the New England, Canadian, and Greenland coasts On one occasion, she even made a tow to Reykjavik, Iceland. Between 1946 and 1971 Seneca only ventured out of the western Atlantic three times. On 1 May 1961, she departed Mayport, Fla., with AFBD-7 in tow and made Holy Loch, Scotland, a month later. Leaving her charge at Holy Loch, Seneca sailed to Penzance, England, on 5 June. She stood out of Penzance on the 13th and arrived in Norfolk Va. on the 24th. In the summer of 1964 she participated in the tow of Oak Ridge (ARMD-;) and YFNB-S6 from Norfolk to Rota, Spain. She sailed to the Mediterranean in 1966 for a five-month deployment with the 6th Fleet after which she resumed her normal routine in the western Atlantic.
Decommissioned in July 1971, Seneca was transferred to the Maritime Administration on 18 November 1971 for layup with the James River Group, National Defense Reserve Fleet. Seneca remains at James River, Va., as of 1 January 1974.