United States L-class submarine


The United States L-class submarines were a class of 11 coastal defense submarines built 1914–1917, and were the most modern and capable submarines available to United States Navy when the country entered World War I. Despite being considered a successful design by the USN, war experience in European waters demonstrated that the boats lacked the range, speed, and endurance to conduct extended patrols in the North Atlantic.

Design

These submarines were built to two distinctly different designs at four separate shipyards. The Electric Boat Company of New York City, later Groton, Connecticut, went the route they followed with previous designs and simply scaled up their standard single hull, spindle shaped, twin propeller, axial rudder design to meet the requirements of the Navy. They were contracted for L-1 through L-4 and L-9 through L-11, and these would be built at EB's sub-contractor, the Fore River Shipbuilding Company, in Quincy, Massachusetts. For the first time EB did away with the rotating bow cap for the torpedo tube muzzle doors. It was replaced by individual faired-in shutter doors that would later become a standard design feature. Simon Lake's Lake Torpedo Boat Company returned to the fold and submitted a very different design that would become L-5 through L-8. These boats were similar in size and capability to the EB design, but they had a ventrally mounted rudder and propeller shafts, a watertight superstructure to aid in surface buoyancy, and different engines and motors. They also had three sets of amidships mounted diving planes, as opposed to EB's standard bow and stern planes. The only one of the four that would actually be built at Lake's Bridgeport, Connecticut, yard was L-5. The Navy wanted some of the boats built at a West Coast shipyard, so Lake sub-contracted with the Craig Shipbuilding Company, of Long Beach, California, to build L-6 and L-7. Desirous of creating their own in-house submarine construction capability, the Navy's Bureau of Construction and Repair obtained a license from Lake to build the L-8 at the government owned Portsmouth Navy Yard, in Kittery, Maine. L-8 would be the first of many submarines built at government Navy Yards.
The Electric Boat submarines, referred to as the L-1-class, had a length of overall, a beam of, and a mean draft of. They displaced, on the surface, and, submerged. All L-class boats had a crew of 2 officers and 26 enlisted men. They all had a diving depth of.
The Lake submarines, referred to as the L-5-class, had a length of overall, a beam of, and a mean draft of. They displaced, on the surface, and, submerged.
For surface running, the Electric Boat submarines were powered by two NELSECO diesel engines, each driving one propeller shaft. When submerged each propeller was driven by an Electro Dynamic electric motor. The Lake boats had two Busch-Sulzer diesels, and two Diehl electric motors. Regardless of designer, the L-class submarines could reach on the surface, and underwater. On the surface, the boats had a range of at, and at submerged.
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 EB boats were also armed with a /23 caliber retractable deck gun forward of the conning tower. The gun was retracted vertically, with a round shield that fit over the top of a well in the superstructure that projected into the pressure hull. Most of the barrel protruded from the deck, resembling a stanchion. The round shield doubled as a blast deflector for the gun crew, and as the watertight top of the well. This gun was roundly disliked by the submarine crews because it lacked range, hitting power, and had the tendency to retract back into the well when fired, presenting a great hazard to the gun crew.
As in previous US designs, the conning tower and fairwater was kept small for reduced drag when submerged. For extended surface runs, the fairwater was augmented with a temporary piping-and-canvas structure which took considerable time to deploy and dismantle. Experience in World War I showed that this was inadequate in the North Atlantic weather, and these boats, along with other submarines serving overseas in that war, E-class and [United States United States K-class submarine|K-class submarine|K-class], had their bridge structures replaced with a permanent steel "chariot" shield on the front of the bridge. Chariot style bridges became standard on later U.S. submarines.

Service

When the US entered the First World War, most of the Electric Boat built submarines required extensive refits at the Philadelphia Navy Yard, which reflected the US Navy's limited experience in submarine ocean operations. In December 1917, the seven boats were sent to Bantry Bay, as Submarine Division 5, for convoy escort and antisubmarine patrols against Imperial German U-boats. The four new Lake design L-boats later deployed to the Azores, in November 1918, as Division 6, to reinforce four K-class submarines, sent there in October 1917. While forward deployed, US L-class submarines had the letter "A" added to the name displayed on the fairwater to avoid confusion with British L-class submarines.
US submarines did not sink any U-boats in World War I, despite the immense effort of getting them to the war zone. Many lessons were learned and these were poured into the design of follow-on submarines. After the war, the L-class were involved in trials of new torpedoes and hydrophone equipment on both the East and West Coasts, before decommissioning in 1922 and 1923. At least L-3, L-9, and L-11 were re-engined with N-boats in 1921. Three EB design boats were scrapped in 1922, the four Lake design boats were scrapped in 1925, and the remainder were scrapped in 1933, under the [London Naval Treaty">United States N-class submarine">N-boats in 1921. Three EB design boats were scrapped in 1922, the four Lake design boats were scrapped in 1925, and the remainder were scrapped in 1933, under the [London Naval Treaty limiting naval armament.

Boats in class

Ship nameBuilderLaid downLaunchedFate
Submarine No. 40Fore River Shipbuilding, Quincy, Massachusetts13 April 191420 January 191511 April 19167 April 1922SS-4017 July 1920Sold for scrapping, 31 July 1922
Submarine No. 41Fore River Shipbuilding, Quincy, Massachusetts19 March 191411 February 191529 September 19164 May 1923SS-4117 July 1920Sold for scrapping, 28 November 1933
Submarine No. 42Fore River Shipbuilding, Quincy, Massachusetts18 April 191415 March 191522 April 191611 June 1923SS-4217 July 1920Sold for scrapping, 28 November 1933
Submarine No. 43Fore River Shipbuilding, Quincy, Massachusetts23 March 19143 April 19154 May 191614 April 1922SS-4317 July 1920Sold for scrapping, 31 July 1922
Submarine No. 44Lake Torpedo Boat Company, Bridgeport, Connecticut14 May 19141 May 191617 February 19185 December 1922SS-4417 July 1920Sold for scrapping, 21 December 1925
Submarine No. 45Craig Shipbuilding Company, Long Beach, California27 May 191431 August 19167 December 191725 November 1922SS-4517 July 1920Sold for scrapping, 21 December 1925
Submarine No. 46Craig Shipbuilding Company, Long Beach, California2 June 191428 September 19167 December 191715 November 1922SS-4617 July 1920Sold for scrapping, 21 December 1925
Submarine No. 48Portsmouth Navy Yard, Kittery, Maine24 February 191523 April 191730 August 191715 November 1922SS-4817 July 1920Sunk as target, 26 May 1926
Submarine No. 49Fore River Shipbuilding, Quincy, Massachusetts2 November 191427 October 19154 August 19164 May 1923SS-4917 July 1920Sold for scrapping, 28 November 1933
Submarine No. 50Fore River Shipbuilding, Quincy, Massachusetts17 February 191516 March 19162 August 19165 May 1922SS-5017 July 1920Sold for scrapping, 31 July 1922
Submarine No. 51Fore River Shipbuilding, Quincy, Massachusetts17 February 191516 May 191615 August 191628 November 1923SS-5117 July 1920Sold for scrapping, 28 November 1933