▁on ▁ 1 ▁June ▁ ▁as ▁part ▁of ▁Con voy ▁O B ▁ 3 1 9 . ▁This ▁was ▁the ▁second ▁most ▁successful ▁U - bo at ▁pat rol ▁of ▁the ▁entire ▁Second ▁World ▁War , ▁with ▁ 1 2 ▁ships ▁s unk ▁for ▁a ▁total ▁of ▁. ▁On ▁ 5 ▁May ▁ 1 9 4 1 , ▁the ▁ 1 0 5 mm ▁deck ▁gun ▁expl oded , ▁w ounding ▁six ▁crew ▁members . ▁U - 1 0 5 ▁returned ▁to ▁Lor ient ▁on ▁ 1 3 ▁June , ▁and ▁remained ▁there ▁until ▁ 3 ▁August , ▁when ▁she ▁depart ed ▁on ▁her ▁third ▁war ▁pat rol . ▁ ▁On ▁ 5 ▁August ▁she ▁was ▁assigned ▁to ▁w olf pack ▁' H ammer ' ▁and ▁remained ▁with ▁it ▁until ▁it ▁was ▁dis band ed ▁on ▁ 1 2 ▁August , ▁when ▁she ▁was ▁re ass igned ▁to ▁w olf pack ▁' Gr ön land ', ▁with ▁which ▁she ▁remained ▁until ▁its ▁dis band ing ▁on ▁ 2 7 ▁August . ▁She ▁was ▁then ▁assigned ▁to ▁w olf pack ▁' M arg ra ve ', ▁and ▁s ank ▁the ▁Pan aman ian ▁merchant ▁ship ▁Mont ana , ▁ ▁part ▁of ▁Con voy ▁SC ▁ 4 2 , ▁on ▁ 1 1 ▁September . ▁She ▁returned ▁to ▁Lor ient ▁nine ▁days ▁later . ▁U - 1 0 5 ▁left ▁Lor ient ▁on ▁her ▁fourth ▁pat rol ▁on ▁ 8 ▁November ▁ 1 9 4 1 ▁and ▁spent ▁ 3 6 ▁days ▁in ▁the ▁North