The H-class of coastal defense submarines were, as usual, scaled up versions of Electric Boat's previous design, the F-class. Significantly, these boats incorporated two watertight bulkheads that separated the control room into a compartment separate from the battery rooms. Three boats (designated design EB-26A by EB) were authorized in Fiscal Year 1910, to begin construction in the spring of 1911. Two were built by Union Iron Works in San Francisco, and one by the Moran Company in Seattle. They were originally named Seawolf, Nautilus, and Garfish, although those names were dropped only a few months after construction was started and before they were launched in favor of the H-class names. They were mostly successful boats, although they suffered from the usual litany of engine unreliability. H-1 was lost to a grounding incident on the Mexican shore in March, 1920 with the loss of four lives.
The H-class design was a very popular one for EB. They sold it in slightly modified form to the UK, Russia, Italy, and Chile. In fact, after the fall of the Tsar, a Russian order for six H-class boats was acquired by the USN from their building yard in Vancouver, British Columbia. After the legalities were cleared up, the submarines, uncompleted in knockdown kit form, were transported to the nearby Puget Sound Navy Yard in Bremerton, WA., where they were completed. They were commissioned as the H-4 to H-9. These boats, designated EB-26R by EB, had only minor differences from their earlier siblings. One notable difference is the lack of a watertight bulkhead between the torpedo room and the forward battery compartment. Since their acquisition was delayed other types had already been ordered by the USN, so these last six boats had hull numbers that fell into the middle of the S-class. This class was fairly successful, but became quickly obsolete after WWI and were discarded in the early 1920's, though the British and the Russians were still using some of their H-class subs in WW II.
Dr. Richard Hendren has contributed to PigBoats his excellent doctoral thesis on the H-class. Please take the time to read through his work at this link.
Seawolf/H-1 (Submarine No. 28, later SS-28)
H-1 underway near San Francisco, 1914. Her torpedo loading skid is raised, indicating that she may be returning from a torpedo firing exercise. The destroyer USS Stewart (Destroyer No. 13) is underway in the background.
H-3 maneuvering up to moor, circa 1915. The location is thought to be San Diego. Towing a submarine was a fairly common occurrence in the early days, and H-3 has installed a large towing shackle in a hole that goes all the way through the superstructure at the bow casting. There is a secondary towing chain run through the fairlead at the tip of the bow and back along the port side edge of the deck to a permanently installed deck padeye. The 2nd man from the left is a Chief Petty Officer and he has a coiled heaving line ready to throw. There are coiled mooring lines on her forward deck.
H-4 at speed in the Pacific off California, approximately 1921-1922. The logo painted on the side of her bridge is for Submarine Division 7. This is the first of three very similar photos taken as the division steamed past the camera man in formation. (See H-5 and H-7 below.)
H-6 steaming past a stately line of battleships off San Pedro, California, approximately 1919. H-6 is displaying one of the many external name variations, in this case she has an additional "6" painted on her bridge, in addition to her name on the side of the fairwater.
On the left is a Wyoming-class ship, and on the right is a South Carolina-class. There is a third battleship visible at the far right, but it can't be identified.
The USS Cheyenne (Monitor No. 10), submarine tender for Submarine Flotilla Two, Pacific Fleet, seen at Bremerton, WA., 1914-1917, along with three H-class submarines. Seen left to right are the H-2, H-3, and the H-1. The H-1 is having some work done on her after end, perhaps maintenance on her screws or engine mufflers. The after end of the hull has been raised using the muzzles of the 12-inch deck guns in the big turret. A strong-back seems to have been lashed across the two barrels. The Cheyenne is likely moored to a dock, as opposed to being anchored out. Various crew can be seen on the Cheyenne's deck, maybe crew from the H-1 have been ordered off while the work is being performed.