, ▁K aga , ▁S ō ry ū , ▁and ▁H iry ū ▁were ▁lost ▁in ▁the ▁Battle ▁of ▁Mid way . ▁ ▁Each ▁k ō k ū ▁sent ai ▁of ▁First ▁Air ▁Fle et ▁t ended ▁to ▁include ▁a ▁pair ▁of ▁aircraft ▁carri ers , ▁and ▁each ▁included ▁the ▁respective ▁h ik ō kit ai / h ik ō ta i ▁( air craft / av iation ▁unit ( s )) ▁of ▁each ▁aircraft ▁car rier . ▁Each ▁k ō k ū ▁sent ai ▁of ▁First ▁Air ▁Fle et ▁was ▁a ▁tact ical ▁unit ▁that ▁could ▁be ▁deployed ▁separately ▁or ▁combined ▁with ▁other ▁k ō k ū ▁sent ai ▁of ▁First ▁Air ▁Fle et , ▁depending ▁on ▁the ▁mission . ▁For ▁example , ▁for ▁operations ▁against ▁New ▁Britain ▁and ▁New ▁Guinea ▁in ▁January ▁ 1 9 4 2 , ▁First ▁K ō k ū ▁Sent ai ▁and ▁Fif th ▁K ō k ū ▁Sent ai ▁participated . ▁ ▁The ▁number ▁( from ▁approximately ▁two ▁dozen ▁up ▁to ▁approximately ▁ 8 0 ▁aircraft ) ▁and ▁type ▁of ▁aircraft ▁varied , ▁based ▁on ▁the ▁capacity ▁of ▁the ▁aircraft ▁car rier . ▁The ▁large ▁fleet ▁carri ers ▁had ▁three ▁types ▁of ▁aircraft ; ▁f igh ters , ▁level / tor ped o ▁bom bers , ▁and ▁d ive ▁bom bers . ▁The ▁smaller ▁carri ers ▁t ended ▁to ▁have ▁only ▁two ▁types ▁of ▁aircraft , ▁f igh ters ▁and ▁tor ped o ▁bom bers . ▁ ▁At ▁the ▁beginning ▁of ▁the ▁Pacific ▁War , ▁First