Intelligence reports received from 1914 to 1916, showed that the
German U-boats, then operating off
Great Britain, far exceeded the capabilities of the
H,
K,
L, and
N classes of USN submarines then in service. If Great Britain were to fall, those boats would be unable to cross the
Atlantic and fight, once they got there, and this drove the requirements for the designs that would become the S-class. The Navy's specifications called for a boat of , with a speed of , and a range between . They would be armed with four
21 inch (533 mm) torpedo tubes and a
/50 caliber deck gun. The Navy turned to its traditional submarine builders, the
Electric Boat Company (EB) and
Lake Torpedo Boat Company, and asked them to submit designs, but for the first time, the Navy itself developed a design to be built at its own Navy Yards. The Navy wanted to diversify the acquisition process and provide some level of competition to Electric Boat and Lake. The Navy requested a prototype from all three designers. The first three boats in name sequence, , , and , were prototypes, authorized in Fiscal Year 1918, and were built to the same basic specifications:
S-1 was a single-hull design by EB,
S-2 was a
double-hull by Lake, and
S-3 was also a double-hull design by the
Bureau of Construction and Repair (BuC&R) (later
Bureau of Ships). Even though the FY-18 boats were considered to be prototypes, the EB and the BuC&R designs, were intended for series production from the very beginning. The boats of the S-class may have been designed to the same set of specification, but like the classes that preceded them, they were very different between the builders. The S-class may be subdivided into four groups of different designs, five if you included the rejected Lake design: • Group I (
S-1 or
S-18 class, or "Holland" type): 25 boats,
S-1 and
S-18 to
S-29, were built by
Bethlehem Steel, at their
Fore River Shipyard, in
Quincy, Massachusetts, and
S-30 to
S-41 at their
Union Iron Works, in
San Francisco, California, as the
subcontractor for the Electric Boat Company. • Group II (
S-3 or
S-4 class, or "Navy" type): 15 boats,
S-3 to
S-13, built at the
Portsmouth Navy Yard, in
Kittery, Maine, and
S-14 to
S-17, at the Lake Torpedo Boat Company, in
Bridgeport, Connecticut. • Group III (
S-42 class, or "Modified Holland" type): 6 boats,
S-42 to
S-47, built by EB, in Quincy. • Group IV (
S-48 class, or "Modified Navy" type): 4 boats,
S-48 to
S-51, built by Lake, in Bridgeport. , Massachusetts, on 17 April 1920, while running
sea trials The EB design,
S-1, formed the basis for the Group I and Group III boats, and were essentially enlarged versions of all their previous designs. A single hull design, all of the ballast tanks were contained within the
pressure hull. The hull was a rounded spindle shape and the rudder was placed at the very end of the hull, aft of the twin screws. Compared to the previous R-boats, Group I S-boats were longer, with more
beam, more
draft, and 60% greater
displacement. This allowed for greater range, larger engines, and higher speed, and more
torpedo reloads, though the number of forward
torpedo tubes was unchanged. , Connecticut, at the time of her
builders' trials in September 1919, many of the men standing on her deck are civilians The Lake design,
S-2, was a modified double-hull type, with ballast tanks wrapped around the inner pressure hull. The stern ended in a flat "shovel" shape which gave the stern needed buoyancy. The rudder was mounted beneath the stern and the pivot structure also supported the stern
diving planes. To gain surface buoyancy, the superstructure atop the boat was partially watertight.
Sea trials showed that the bow tended to burrow into the waves so Lake added a buoyancy tank to the bow, which gave it a humped appearance. This boat suffered from poor maneuverability and was overcomplicated. It proved to be unreliable and was not well liked by its crew. The Navy did not choose it for mass production and no further boats were produced to this design. , a features that were added later The BuC&R design,
S-3, formed the basis for the Group II and Group IV boats, was a full double hull type that incorporated some design features of both the Electric Boat and Lake designs. At long, it was longer, and a little wider, than the other two designs. The battery was contained in one large compartment forward of the control room, giving the boat a long, sleek appearance. The long hull ended in a sharp vertical "chisel" at the stern, and the rudder and stern dive planes were ventrally mounted under the hull, behind the propellers. One drawback to the "Navy" type was that their main ballast tanks were divided into an upper and lower tank, which caused them to dive slow due to the fact that the upper tank wouldn't start filling until it was submerged. After WWI, US officers were impressed by the stern torpedo tubes on the German U-boats, the last four of Group II, and all four of Group IV boats, had an additional single stern torpedo tube added. Group IV was also longer and had less draft. A
deck gun had initially been requested, but due to space restraints and drag, all S-boats were eventually outfitted with a
/50 caliber deck gun, a significant increase over the
/23 caliber and
3-in/50 caliber guns of previous US submarines. This was due to observations that the German U-boats frequently used their deck guns, and many U-boats were equipped with deck guns. Another improvement was the
conning tower fairwater. Previous US submarines had small fairwaters to reduce drag and improve submerged speed. Experience gained on North Atlantic patrols during World War I showed that the boats would be spending considerable time on the surface and thus needed better protection for the bridge watchstanders. Examination of captured U-boats after the
Armistice also showed that a larger fairwater with permanent grab rails was preferable when surfaced in the North Atlantic, so S-boats were built or refitted with an improved and much larger fairwater. The first S-boat placed into commission was
S-3, on 30 January 1919, followed in order by , , , and
S-2. EB's contractors in Quincy and San Francisco, worked in parallel, with the first unit,
S-1, built in Quincy, and commissioned on 5 June 1920, and the first unit from San Francisco, being the , commissioned on 29 October 1920. SS-163 to SS-168, "Modified Holland", and SS-173 to SS-176, "Modified Navy", were cancelled, and contrary to later practice, the
hull numbers were used for subsequent submarines. Some of the material for these was used by EB to build the
Peruvian Navy's four R-boats. Future
Admiral,
Hyman G. Rickover, was assigned to . He later credited the "faulty, sooty, dangerous and repellent engineering" of the S-class boats with inspiring his obsession for high engineering standards. scouting
seaplane (Bureau # A-6525) being assembled on the after deck of
S-1 (SS-105), at
Hampton Roads, Virginia, 24 October 1923 In 1923,
S-1 experimented with a
Martin MS-1 seaplane, an idea the
Japanese would later adopt. A cylindrical
hangar was installed on the after deck to house a single Martin MS-1 seaplane. Tests showed the concept to be unworkable, and the equipment was subsequently removed. The hangar was later reused and rebuilt as the prototype for the
McCann Rescue Chamber, a diving bell for rescuing crewmen from sunken submarines. ==Service==