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SS-52 T-1 Schley

Even before World War One - and only a dozen years after USS Holland (SS-1) inaugurated the Navy's undersea force - U.S. naval strategists had already begun to postulate submarines that could operate in closer collaboration with the surface fleet than the Navy's existing classes, which had been designed primarily for coastal defense. These notional "fleet" submarines would necessarily be larger and better armed, but primarily, they would need a surface speed of some 21 knots to be able to maneuver with the battleships and cruisers of the line.

Thus, in the summer of 1913, Electric Boat's chief naval architect, former naval constructor Lawrence Y. Spear, proposed two preliminary fleet-boat designs for consideration in the Navy's 1914 program. In the ensuing authorization of eight submarines, Congress stipulated that one should ".be of a seagoing type to have a surface speed of not less than twenty knots." After the money was found - in 1915 - this first fleet boat was laid down in June 1916 as a larger version of Spear's original concept.

Electric Boat received a commission to design the three boats of the 20-knot T, or AA class, with a normal displacement of 1107 tons. On paper these characteristics, adopted during the First World War, brought the Navy one step closer to the "fleet submarine," a submersible that could keep pace with the battle fleet. The fleet submarine would be an undersea boat possessing the sea keeping qualities and endurance capability required for long-range operations, as scouts for the surface fleet.

The FY1915 program (approved 30 June 1914) included a prototype fleet submarine that was capable of 20 knots surface speed. Spear combined two 8-cylinder 1,000hp diesel engines on each shaft and incorporated a 60hp auxiliary diesel generator, the first in a US submarine. The strength of the hull was sacraficed for weight consideration resulting in a test depth of only 150 feet. With a surface displacement of 1,106 tons - 1,487 tons submerged - on a length of 270 feet, Schley (later USS AA-1, and finally USS T-1) was twice as large as any previous U.S. submarine. To achieve the required surface speed, two tandem 1,000 horsepower diesel engines on each shaft drove twin screws, and a separate diesel generator was provided for charging batteries.

The submarine was named (against convention) Schley [after deceased Spanish-American war hero Winfield Scott Schley] and renamed AA-1 on 23 August 1917 to free the name Schley for Destroyer No. 103. Later this was changed to simply, T-1.

T-1 was laid down at Fore River Shipbuilding in June 1916; two more submarines of this type were approved in the FY1916 program (T-2 and T-3) and they were laid down at the same yard in May 1917.

On 17 July 1920, while the submarine was being fitted-out, the Navy adopted its modern system of alpha-numeric hull numbers, and the fleet submarine was designated SF-1. On 20 September, she was renamed T-1. Thus, by the time she began active service that fall, she was known as T-1 (SF-1). Two sisters authorized in 1915 - USS T-2 (originally AA-2, SS-60) and USS T-3 (originally AA-3, SS-61) commissioned 1920-22. T-2 and T-3 were redesigned to incorporate two 4-inch/50 deck guns during World War One but were completed with one.

In operational service the T-boats were found to have entirely unreliable engineering; the Navy considered de-rating their speed to 16-17 knots. Their operational range fell short of requirements, about 3000 miles at 11 knots; having been designed for 5540 miles at 14 knots. Their time to submerge was inadequate.

Although Schley made their design speed of 20 knots, insoluble torsional vibration problems with their tandem engines made them very troublesome ships, and they were decommissioned in 1922 and 1923 after a service life of only a few years. T-3 was recommissioned in 1925 to test a new 3000hp MAN engine. T-3 was decommissioned in July 1927 and all three scrapped in 1930 as a result of the London Naval Treaty.

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Page last modified: 22-07-2011 17:42:11 ZULU