USS O-9
submarine of the United States
USS O-9 (SS-70), also known as "Submarine No. 70", was one of 16 O-class submarines of the United States Navy commissioned during World War I. She was recommissioned on 14 April 1941, prior to the United States entry into WWII, for use as a trainer. On 20 June 1941, she sank approximately 15 mi (24 km) off Portsmouth, New Hampshire, with the loss of 33 lives. The wreck was located in 1997.
Design
The O-1-class submarines were designed to meet a Navy requirement for coastal defense boats. The submarines had a length of 172 ft 4 in (52.5 m) overall, a beam of 18 ft 1 in (5.5 m), and a mean draft of 14 ft 5 in (4.4 m). They displaced 520 long tons (530 t) on the surface and 629 long tons (639 t) submerged. The O-class submarines had a crew of 2 officers and 27 enlisted men. They had a diving depth of 200 ft (61.0 m).
For surface running, the boats were powered by two 440-brake-horsepower (328 kW) NELSECO 6-EB-14 diesel engines, each driving one propeller shaft.
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