 SM U @-@ 40 or U @-@ XL was a U @-@ 27 class U @-@ boat or submarine for the Austro @-@ Hungarian Navy . U @-@ 40 , built by the Austrian firm of Cantiere Navale Triestino ( CNT ) at the Pola Navy Yard , was launched in April 1917 and commissioned in August . She had a single hull and was fitted with a single propeller shaft . She had a crew of 30 . Her armament consisted of one 10 cm (3. kwieta ) gun and four 40 cm (1.65a ) torpedo tubes .
SM U @-@ 4