United States O-class submarine

The United States Navy's O class submarines were created out of the lessons learned from the United States L class submarine. The O class were more robust with greater power and endurance for ocean patrols. The O class were built much faster than previous classes and were commissioned in 1918. The group 2 boats entered service just before the end of World War I. Eight of the group 1 boats survived to serve in World War II as training boats when they were recommissioned in 1941.

The class originally operated in the anti-submarine role off the USA's East Coast. Two of the boats, USS O-4 (SS-65) and USS O-6 (SS-67), came under fire from a British merchantman in the Atlantic on 24 July 1918. The steamer scored six hits on O-4's conning tower and pressure hull before her identity was discovered. O-4 suffered minor damage caused by shell splinters. USS O-3 (SS-64) to USS O-10 (SS-71) boats formed part of the twenty-strong submarine force that left Newport, Rhode Island on 2 November 1918 for the Azores but the task force was recalled after the Armistice was signed nine days later.



The second group of boats suffered from electrical problems. USS O-11 (SS-72) was immediately sent to the Philadelphia Navy Yard for a five-month overhaul. USS O-13 (SS-74) sank the patrol boat Mary Alice in a collision while she (O-13) was submerged. USS O-15 (SS-76) also underwent a refit but was sent into reserve soon after before she went into service at Coco Solo in the Panama Canal Zone. This also involved another overhaul. USS O-16 (SS-77) also underwent a refit soon after commissioning and later suffered a fire in her conning tower in December 1919. All of the group 2 boats were decommissioned in July 1924 and were scrapped in July 1930 under the terms of the London Naval Treaty. USS O-12 (SS-73) however was used in an Arctic expedition by Sir Hubert Wilkins and was renamed Nautilus. After being returned to the US Navy, she was sunk in a Norwegian fjord in November 1931.

The first group served well although USS O-5 (SS-66) was rammed by a cargo ship and sunk near the Panama Canal with the loss of three crew members. All of the group 1 boats were recommissioned in 1941 to serve as training boats based at New London, Connecticut. The remaining boats were taken out of service four months later except for USS O-9 (SS-70) which sank in deep submergence trials in June 1941. Thirty-three of her crew were lost.



Boats in class
Group 1 Group 2
 * USS O-1 (SS-62)
 * USS O-2 (SS-63)
 * USS O-3 (SS-64)
 * USS O-4 (SS-65)
 * USS O-5 (SS-66)
 * USS O-6 (SS-67)
 * USS O-7 (SS-68)
 * USS O-8 (SS-69)
 * USS O-9 (SS-70)
 * USS O-10 (SS-71)
 * USS O-11 (SS-72)
 * USS O-12 (SS-73)
 * USS O-13 (SS-74)
 * USS O-14 (SS-75)
 * USS O-15 (SS-76)
 * USS O-16 (SS-77)