▁up ▁to ▁. ▁ ▁The ▁sub marine ▁had ▁a ▁maximum ▁surface ▁speed ▁of ▁ ▁and ▁a ▁maximum ▁sub mer ged ▁speed ▁of ▁. ▁When ▁sub mer ged , ▁the ▁boat ▁could ▁operate ▁for ▁ ▁at ▁; ▁when ▁sur fac ed , ▁she ▁could ▁travel ▁ ▁at ▁. ▁U - 4 5 1 ▁was ▁fitted ▁with ▁five ▁ ▁tor ped o ▁tub es ▁( four ▁fitted ▁at ▁the ▁bow ▁and ▁one ▁at ▁the ▁stern ), ▁four teen ▁tor ped o es , ▁one ▁ ▁SK ▁C / 3 5 ▁naval ▁gun , ▁ 2 2 0 ▁r ounds , ▁and ▁a ▁ ▁C / 3 0 ▁anti - air craft ▁gun . ▁The ▁boat ▁had ▁a ▁complement ▁of ▁between ▁forty - four ▁and ▁si xty . ▁ ▁Service ▁history ▁The ▁boat ▁set - off ▁from ▁K iel ▁and ▁moved ▁into ▁Norwegian ▁waters ▁between ▁ 2 3 ▁June ▁and ▁ 2 4 ▁July ▁ 1 9 4 1 . ▁▁ 1 st ▁and ▁ 2 nd ▁pat rol s ▁She ▁depart ed ▁Kir ken es ▁in ▁the ▁far ▁north ▁on ▁ 3 0 ▁July ▁ 1 9 4 1 , ▁pat rolled ▁the ▁Bar ents ▁Sea ▁and ▁s ank ▁one ▁war ship ▁of ▁ 5 5 0 ▁tons , ▁the ▁Soviet ▁cor v ette ▁Z hem ch ug ▁( No ▁ 2 7 ), ▁on ▁ 1 0 ▁August . ▁She ▁returned ▁to ▁Kir ken es ▁on ▁ 1 2 ▁August . ▁ ▁Her ▁second ▁pat rol , ▁between ▁ 1 9 ▁August ▁and ▁