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 168feet overall, a beam of 17feet and a mean draft of 13feet. They displaced 450LT on the surface and 548LT submerged. The L-class submarines had a crew of 28 officers and enlisted men. They had a diving depth of 200feet.[1]
For surface running, the Electric Boat submarines were powered by two 4500NaN0 diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 170hp electric motor. They could reach 14kn on the surface and underwater. On the surface, the boats had a range of 5150nmi at [1] and 150nmi at 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]
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.