United States E-class submarine

USS E-1, ex-Skipjack, lead ship of the class, underway, starboard side view, at the Naval Review at New York City, 4 October 1912
Class overview
Name	E class
Builders	Electric Boat (design) Fore River Shipbuilding Company, Quincy, Massachusetts
Operators	United States Navy
Preceded by	D class
Succeeded by	F class
Built	1911–1912
In commission	1912–1921
Completed	2
Retired	2
General characteristics
Type	Submarine
Displacement	287 long tons (292 t) surfaced 342 long tons (347 t) submerged
Length	135 ft 3 in (41.22 m)
Beam	14 ft 7 in (4.45 m)
Draft	11 ft 8 in (3.56 m)
Installed power	700 hp (522 kW) (diesel) 600 hp (447 kW) (electric)
Propulsion	2 × NELSECO diesel engines 2 × Electro Dynamic electric motors 2 × 60-cell batteries 2 × Propellers
Speed	13.5  kn (25.0 km/h; 15.5 mph) surfaced 11.5 kn (21.3 km/h; 13.2 mph) submerged
Range	2,100  nmi (3,900 km; 2,400 mi) at 11 kn (20 km/h; 13 mph) surfaced 100 nmi (190 km; 120 mi) at 5 kn (9.3 km/h; 5.8 mph) submerged
Test depth	200 ft (61 m)
Capacity	8,486 US gal (32,120 L; 7,066 imp gal) fuel
Complement	1 officer 19 enlisted
Armament	4 × 18 inch (450 mm) bow torpedo tubes (4 torpedoes)

The E-class submarines were a class of two United States Navy submarines, built by the Fore River Shipbuilding Company of Quincy, Massachusetts, under a subcontract from the Electric Boat Company. They were used as coastal and harbor defense submarines prior to World War I. When hostilities broke out, the E class were mostly used as training boats; however, E-1 operated on war patrols based in the Azores. During this time, the need for an improved permanent bridge structure was discovered; the temporary piping-and-canvas bridges were inadequate in the North Atlantic.

Design

The two E-class submarines were analogous to the preceding D-class submarine, with very similar size and displacement and the same armament. ^[1] They were essentially diesel powered D-class boats, ^[2] and were the first US diesel-powered submarines. The French submarine Z (Q 36), was the first in the world, in 1905. ^[3] Although early diesels were unreliable and the E class engines were replaced in 1915, diesels rapidly supplanted gasoline-fueled engines aboard submarines worldwide, to eliminate the substantial risk of gasoline fumes settling into the bilges of the boat at explosive concentrations.

Submerged controllability problems associated with the ever increasing size of USN submarines led the force to adopt bow diving planes for the first time in this class. ^[4] The bow planes were for precision depth control, ^[5] while the traditional set of stern diving planes handled angle control. D-2, of the previous class, tested a prototype set of bow planes and the tests were entirely successful. ^[6] A larger and retractable set was installed on the E-class, setting the standard that lasted until the Skipjack-class nuclear submarines of the late 1950s.

The small conning tower fairwater, also known as a sail, initially precluded any sort of bridge structure for surface cruising. For extended surface runs, a temporary piping-and-canvas structure was erected to give the topside watchstanders some protection from the elements. ^[4] The considerable time required to dismantle that structure made crash diving the boat impossible, but that was not seen as an impediment as USN doctrine did not call for crash dives at that time. Experience in World War I showed that the piping-and-canvas structure was inadequate in North Atlantic weather, and USN submarines serving overseas in that war (E, K, and L-classes) had the forward structure of the fairwater modified with a metal "chariot" shield. Starting in 1918-1919, using lessons learned from overseas experience, US submarines had bridges more suited to surfaced operations in rough weather. ^[7] By 1920, even E-2 had been retrofitted with a permanent metal chariot bridge structure. ^[4]

History

The E-class, and similar early submarines, were known as "pig boats" due to foul living quarters and unusual hull shape. ^[8] The E class was used to test and evaluate tactics and new equipment, but was quickly overtaken by newer long-range, ocean-going submarines. E-1 was forward deployed to the Azores, in World War I, the oldest and smallest US submarine to perform war patrols in that war. The class was decommissioned and scrapped in 1922, to comply with the Washington Naval Treaty.

Boats in class

The following ships of the class were constructed. ^{[9] [10]}

Construction data

Ship name	Hull class and no.	Builder	Laid down	Launched	Comm.	Decomm.	Renamed	Rename date	Reclass. hull no.	Reclass. hull no. date	Fate
Skipjack	Submarine No. 24	Fore River Shipyard, Quincy, Massachusetts	22 December 1909	27 May 1911	14 February 1912	20 October 1921	E-1	17 November 1911	SS-24	15 July 1920	Sold for scrapping, 19 April 1922
Sturgeon	Submarine No. 25			16 June 1911			E-2		SS-25

References

1. Hedman & Johnston 2025.
2. Friedman 1995, p. 58.
3. Gardiner 1985, p. 207.
4. Hedman & Johnston 2025a.
5. Gardiner 1985, p. 127.
6. Hedman & Johnston 2025b.
7. Friedman 1995, pp. 77, 81, 85.
8. Pike 2005.
9. Priolo & E-1.
10. Priolo & E-2.

Bibliography

• Hedman, Ric; Johnston, David (8 May 2025). "Submarine Specifications" . Retrieved 24 September 2025.
• Hedman, Ric; Johnston, David (8 May 2025a). "E-class" . Retrieved 24 September 2025.
• Hedman, Ric; Johnston, David (8 May 2025b). "E-class photos" . Retrieved 24 September 2025.
• Friedman, Norman (1995). US Submarines through 1945: An Illustrated Design History. Annapolis: Naval Institute Press. ISBN   1-55750-263-3.
• Gardiner, Robert (1985). Conway's All the World's Fighting Ships 1906–1921. Conway Maritime Press. ISBN   0-85177-245-5.
• Pike, John (27 April 2005). "SS-24 E-1 Skipjack". globalsecurity.org. Retrieved 10 June 2009.
• Priolo, Gary. "Skipjack / E-1 (SS-24)". NavSource. Retrieved 24 September 2025.
• Priolo, Gary. "Sturgeon / E-2 (SS-25)". NavSource. Retrieved 24 September 2025.