tre aty ▁cru is ers " ▁were ▁the ▁two ▁of ▁the ▁ ▁ordered ▁in ▁ 1 9 2 6 , ▁which ▁emphas ized ▁arm ament ▁and ▁speed ▁at ▁the ▁exp ense ▁of ▁protection . ▁These ▁ships ▁were ▁followed ▁by ▁the ▁six ▁vessels ▁of ▁the ▁North am pton ▁class ▁ordered ▁in ▁ 1 9 2 7 ▁with ▁slightly ▁better ▁arm or , ▁and ▁introduced ▁the ▁configuration ▁of ▁three ▁triple ▁tur rets ▁which ▁would ▁become ▁standard ▁on ▁U . S . ▁Navy ▁heavy ▁cru is ers . ▁The ▁Port land ▁class ▁was ▁a ▁modification ▁of ▁both ▁the ▁P ens ac ola ▁and ▁North am pton ▁designs . ▁ ▁Order ed ▁for ▁the ▁U . S . ▁Navy ▁in ▁fis cal ▁year ▁ 1 9 3 0 , ▁the ▁Port land ▁class ▁was ▁originally ▁designated ▁as ▁a ▁light ▁cru iser , ▁and ▁given ▁the ▁h ull ▁classification ▁symbol ▁CL , ▁being ▁re - design ated ▁a ▁heavy ▁cru iser ▁with ▁the ▁symbol ▁CA ▁on ▁ 1 ▁July ▁ 1 9 3 1 , ▁due ▁to ▁their ▁arm ament , ▁in ▁accord ance ▁with ▁the ▁London ▁Naval ▁Tre aty . ▁Origin ally , ▁eight ▁cru is ers ▁were ▁en vision ed ▁as ▁modified ▁North am pton - class ▁vessels , ▁but ▁eventually ▁two ▁of ▁these ▁became ▁the ▁Port land ▁class , ▁with ▁the ▁remaining ▁six ▁eventually ▁being ▁further ▁modified ▁into ▁the ▁succeed ing ▁. ▁The ▁first ▁three ▁New ▁Orleans - class ▁cru is ers , ▁New ▁Orleans , ▁Ast oria , ▁and ▁Min ne apolis , ▁were