Armament
The U-10 class boats were equipped with two 45 cm (17.7 in) torpedo tubes located in the front and carried a complement of two torpedoes. The German Type UB I submarines were additionally equipped with a 8 mm (0.31 in) machine gun, but it is not clear from sources if U-10 and U-11, the former German boats, were either equipped with them or, if so, retained them in Austro-Hungarian service. In October 1916, all the boats except U-11 received 37 mm/23 (1.5 in) quick-firing (QF) guns. U-11 received a 66 mm/18 (2.6 in) gun originally planned for U-14 (which received a larger gun instead). In November 1917, the 37 mm guns were replaced by 47 mm/23 (1.9 in) QF guns.
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