AT-10
Displacement 917
Length 157'1"
Beam 30'6"
Draw 15'6"
Speed 12 k
Complement
Armament 2 3-pounders
Class Patapsco

The fifth Patapsco (AT-10) was laid down at the Portsmouth, N.H., Navy Yard, 12 May 1907; launched 29 June 1908; placed in partial commission 28 July 1909 for transit to Boston for completion; and commissioned in full, at Boston, 1 July 1911.

Prior to the outbreak of World War I, Patapsco operated off the eastern seaboard as a tender for the Atlantic Fleet. Then, for the first months of the war, she served with Mine Squadron 1 as nets were planted and mine experiments carried out. In November 1917, as plans for a mine barrage across the North Sea necessitated a drastic increase in trained mine personnel, a training camp was established at Newport R.I., and Patapsco included seamanship training duties in her schedule.

In early spring, 1918, new ships were added as the squadron prepared for overseas deployment. Patapsco, with Patuxent, sailed early to escort submarine chasers to Brest, whence they steamed to Naval Base 18, Inverness, Scotland, arriving 24 June. For the remainder of the war she remained in the area inspecting mine fields and keeping up communications between mine bases.

Following the Armistice, Patapsco, again with Patuxent, conducted experiments to develop the gear and techniques to sweep the North Sea Mine Barrage. In December, she accompanied wooden vessels to the barrage to determine the effectiveness of the remaining mines, and found most still "live".

Experimental activities and tender duties continued through the winter months and in March, 1919, Patapsco and Patuxent tested "electrical protective devices" to render mine exploders ineffective. On the 22nd she arrived off the mined area, which stretched between the Orkney Island and the Norwegian coast. By afternoon the device's efficacy had been proven, but other problems were discovered. Among them the danger of countermined mines.

On the last sweep of the day Patapsco exploded an upper level mine. Two lower level mines were detonated by the first, one directly beneath Patuxent. Damage to the latter was repaired quickly and both vessels soon returned to the Barrage for experiments to minimize the danger of countermining.

In April the base of operations was moved to Kirkwall. At the end of the month minesweeping operations began. On 9 July, during the fourth operation, Patapsco fell victim to the danger she had worked against. Three low level mines, countermined, exploded beneath her. Luckily, and unlike six other vessels mined that day, the tug's damage was minimal.

Patapsco continued operations with the North Sea Minesweeping Detachment until 25 November, then after availability in England, sailed for the United States. In January, 1920, she reported to the 1st Naval District, at Boston, for a two and a half year tour. Then, in July 1922, she sailed south to San Domingo where she remained as tender until the summer of 1924. Returning to the east coast, she entered the Norfolk Navy Yard for inactivation, decommissioning 16 January 1925. She remained in reserve at Norfolk until struck from the Navy List 4 March 1936. Her hull was sold for scrapping, 18 June 1936, to the Boston Iron and Metal Co., Baltimore, Md.