▁become ▁redundant , ▁the ▁H AA ▁guns ▁began ▁to ▁be ▁used ▁for ▁a ▁variety ▁of ▁ground ▁tasks , ▁such ▁as ▁bomb ard ment , ▁counter - b atter y ▁fire , ▁and ▁anti - t ank ▁sho ots . ▁ 6 0 th ▁H AA ▁Regiment ▁was ▁engaged ▁in ▁this ▁way ▁during ▁the ▁Battle ▁of ▁Ca en , ▁and ▁then ▁in ▁AA ▁defence ▁of ▁the ▁city ▁( under ▁ 1 0 0 th ▁AA ▁B de ) ▁after ▁its ▁capture . ▁ ▁North ▁West ▁Europe ▁After ▁the ▁Al lied ▁break out ▁from ▁the ▁Norm andy ▁beach head , ▁ 6 0 th ▁H AA ▁R gt ▁joined ▁ 7 4 th ▁AA ▁B de ▁in ▁guard ing ▁the ▁cross ings ▁of ▁the ▁Seine ▁and ▁then ▁moved ▁to ▁Bou log ne ▁on ▁ 1 2 ▁September . ▁Here ▁it ▁was ▁assigned ▁to ▁II ▁Canadian ▁Corps ▁to ▁act ▁as ▁medium ▁art illery ▁for ▁the ▁attack ▁on ▁the ▁German ▁g arrison ▁of ▁the ▁port , ▁which ▁held ▁out ▁for ▁eight ▁days . ▁The ▁ 3 . 7 - inch ▁g ins ▁of ▁ 6 0 th ▁and ▁ 2 nd ▁Canadian ▁H AA ▁R g ts ▁took ▁part ▁in ▁prolong ed ▁sho ots , ▁including ▁a ▁high ▁proportion ▁of ▁air bur st ▁sh ots . ▁Both ▁reg iments ▁reported ▁that ▁oil ▁squ irt ed ▁out ▁of ▁the ▁guns ' ▁buffer ▁and ▁recuper ator ▁cas ings , ▁while ▁the ▁bar rel s ▁got ▁so ▁hot ▁that ▁they ▁showed ▁a ▁visible ▁dro op . ▁All ▁ 2 4