USS L-11 in Bantry Bay, Ireland, during World War I. "A" (for "American") has been added to her markings to distinguish her from the British submarine HMS L11.
History
United States
Name	USS L-11
Builder	Fore River Shipbuilding Company, Quincy, Massachusetts
Laid down	17 February 1915
Launched	16 May 1916
Commissioned	15 August 1916
Decommissioned	28 November 1923
Fate	Scrapped, 28 November 1933
General characteristics
Class and type	L-class submarine
Displacement	450 long tons (457 t) surfaced 548 long tons (557 t) submerged
Length	168 ft 6 in (51.36 m)
Beam	17 ft 5 in (5.31 m)
Draft	13 ft 7 in (4.14 m)
Installed power	900 bhp (670 kW) (diesel) 340 hp (250 kW) (electric)
Propulsion	2 × diesel engines 2 × electric motors
Speed	14 knots (26 km/h; 16 mph) surfaced 10.5 knots (19.4 km/h; 12.1 mph) submerged
Range	3,300 nmi (6,100 km; 3,800 mi) at 11 knots (20 km/h; 13 mph) on the surface 150 nmi (280 km; 170 mi) at 5 knots (9.3 km/h; 5.8 mph) submerged
Test depth	200 feet (61.0 m)
Complement	28 officers and enlisted men
Armament	4 × bow 18-inch (450 mm) torpedo tubes 1 × 3"/23 caliber deck gun

USS L-11 (SS-51) was an L-class submarine of the United States Navy.

Description

The L-class boats designed by Electric Boat (L-1 to L-4 and L-9 to L-11) were built to slightly different specifications from the other L boats, which were designed by Lake Torpedo Boat, and are sometimes considered a separate class. The Electric Boat submarines had a length of 168 feet 6 inches (51.4 m) overall, a beam of 17 feet 5 inches (5.3 m) and a mean draft of 13 feet 7 inches (4.1 m). They displaced 450 long tons (460 t) on the surface and 548 long tons (557 t) submerged. The L-class submarines had a crew of 28 officers and enlisted men. They had a diving depth of 200 feet (61.0 m).^[1]

For surface running, the Electric Boat submarines were powered by two 450-brake-horsepower (336 kW) diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 170-horsepower (127 kW) electric motor. They could reach 14 knots (26 km/h; 16 mph) on the surface and 10.5 knots (19.4 km/h; 12.1 mph) underwater. On the surface, the boats had a range of 5,150 nautical miles (9,540 km; 5,930 mi) at 11 knots (20 km/h; 13 mph)^[1] and 150 nmi (280 km; 170 mi) at 5 knots (9.3 km/h; 5.8 mph) submerged.^[2]

The boats were armed with four 18 inch (450 mm) torpedo tubes in the bow. They carried four reloads, for a total of eight torpedoes. The Electric Boat submarines were initially not fitted with a deck gun; a single 3"/50 caliber gun on a disappearing mount was added during the war.^[2]

Construction and career

Assigned to the Atlantic Submarine Flotilla, L-11 operated along the East Coast developing new techniques of undersea warfare until April 1917. After the United States's entry into World War I, submarines were needed to protect Allied shipping lanes to Europe, and L-11 departed Boston, Massachusetts, on 4 December to undertake the task. Following a period of patrol and repair in the Azores, the submarine arrived Ireland in mid-February 1918 to Join Submarine Division 5 (SubDiv 5) in anti-submarine patrol off the British Isles. For the next nine months, she ranged shipping lanes, sighting enemy U-boats on three occasions. On 11 May, she made a torpedo attack on an enemy submarine with inconclusive results.

After the Armistice with Germany, L-11 operated out of the Isle of Portland, England, until 3 January 1919 when she sailed for the United States. Arriving Philadelphia, Pennsylvania, on 1 February, she operated off the East Coast for the next four years developing submarine warfare tactics. L-11 decommissioned at Hampton Roads, Virginia, on 28 November 1923, and was scrapped on 28 November 1933.