▁cru is ers ▁were ▁converted , ▁three ▁of ▁which ▁were ▁already ▁mid - const ruction . ▁ ▁Port land ▁served ▁in ▁many ▁engag ements ▁including ▁the ▁Battle ▁of ▁Cor al ▁Sea , ▁the ▁Battle ▁of ▁Mid way ▁and ▁the ▁Gu adal can al ▁Camp aign , ▁where ▁she ▁was ▁sever ely ▁dam aged ▁but ▁non eth eless ▁able ▁to ▁return ▁to ▁service . ▁She ▁later ▁fought ▁in ▁the ▁Battle ▁of ▁Ley te ▁G ulf ▁and ▁the ▁Battle ▁of ▁Ok ina wa . ▁Indian apolis ▁served ▁as ▁a ▁fleet ▁flags hip ▁for ▁much ▁of ▁the ▁war ▁and ▁fought ▁in ▁the ▁Battle ▁of ▁Philipp ine ▁Sea ▁and ▁the ▁Battle ▁of ▁I wo ▁J ima . ▁On ▁ 3 0 ▁July ▁ 1 9 4 5 , ▁after ▁transport ing ▁components ▁for ▁the ▁nuclear ▁weapons ▁Little ▁Boy ▁and ▁F at ▁Man ▁from ▁the ▁United ▁States , ▁she ▁was ▁tor ped o ed ▁by ▁the ▁. ▁Due ▁to ▁a ▁series ▁of ▁errors ▁and ▁mis communic ations ▁her ▁loss ▁was ▁not ▁discovered ▁for ▁several ▁days , ▁and ▁only ▁ 3 1 6 ▁of ▁her ▁ 1 , 1 9 5 ▁crew ▁surv ived ▁– ▁the ▁greatest ▁single ▁loss ▁of ▁life ▁at ▁sea , ▁from ▁a ▁single ▁ship , ▁in ▁the ▁history ▁of ▁the ▁U . S . ▁Navy . ▁ ▁Background ▁ ▁The ▁Port land ▁class ▁was ▁the ▁third ▁class ▁of ▁heavy ▁cru iser ▁to ▁be ▁constructed ▁by ▁the ▁United ▁States ▁Navy ▁following ▁the ▁Washington ▁Naval ▁Tre aty ▁of ▁ 1 9 2 2 . ▁The ▁first ▁"