They made up the bulk of the USN submarine service in the interwar years and could be found in every theater of operations.

[3] The Electric Boat and BuC&R designs were put into series production in later fiscal year appropriations.

SS-159 to SS-168 (2nd Holland) and SS-173 to SS-176 (2nd Navy Yard) were cancelled and, contrary to later practice, the hull numbers were used for subsequent submarines.

[6] Intelligence reports received from 1914 to 1916 showed that the German U-boats then operating off Great Britain far exceeded the capabilities of the then current H, K, L, and N classes of USN submarines.

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 800 tons, with a speed of 11-14 knots and a range between 3400 and 5400 nautical miles.

The Navy wanted to diversify the acquisition process and provide some level of competition to Electric Boat.

The battery was contained in one large compartment forward of the control room, giving the boat a long, sleek appearance.

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.

During builder's sea trials both boats experienced severe torsional drive train vibrations during their required high-speed runs.

Subsequent investigation showed that the crankshafts of the NELSECO 8-EB-15 engines (built by an Electric Boat subsidiary) were of an insufficient diameter, and thus were not stiff enough to resist the power stroke of each cylinder/piston as it fired, resulting in excessive torsional twisting.

Eventually, the Navy Department, faced with the prospect of having a majority of the S-class being unable to meet its desired operational parameters, acquired additional funding for EB to rebuild the engines with a crankshaft of increased diameter.

This solved the torsional vibration problem, but the rebuild work considerably delayed the delivery of the EB boats to the Navy, resulting in average build times exceeding 4 1/2 years.

[19] Once the engine problem was resolved, the EB boats turned in excellent service to the USN, with many serving until the end of WWII.

[20] At the entry of the United States into World War II in December 1941, the S-class submarines ranged in age from 16 to 21 years.

Twenty S-boats were awarded battle stars and 17 were credited with sinking a collective total of 42 Japanese ships.

Smaller and slower than the later fleet submarines produced for war service, and lacking the range for Pacific Ocean patrols (as well as being 20 years old), they were used in reconnaissance and supply roles, as well as for coastal defense.

S-boats operated in the Alaska theater during the aftermath of the Battle of the Aleutian Islands, based out of Dutch Harbor.

In the aftermath of the disastrous defeat of the USN and RAN at the Battle of Savo Island, the S-44 encountered the withdrawing Japanese force near Kavieng on the morning of 10 August 1942.

Having found themselves in the perfect position, the crew of the S-44 launched a spread of four Mark 10 torpedoes, three of which hit the heavy cruiser Kako.