. ▁ ▁Third ▁mission ▁Cow burn ' s ▁third ▁mission ▁was ▁to ▁be ▁his ▁most ▁important . ▁Par ach uting ▁again ▁from ▁a ▁Hal if ax ▁bom ber ▁on ▁ 1 1 ▁April ▁ 1 9 4 3 , ▁Cow burn ▁now ▁took ▁control ▁of , ▁and ▁managed ▁the ▁T IN K ER ▁circuit ▁from ▁Tro yes , ▁the ▁capital ▁of ▁the ▁A ube ▁depart ement . ▁ ▁Cow burn ▁reviews ▁the ▁intelligence ▁gather ing ▁in ▁the ▁area ▁and ▁builds ▁up ▁detailed ▁information ▁for ▁a ▁comm ando - style ▁attack ▁on ▁mar sh alling ▁yard ▁in ▁Tro yes ▁( the ▁largest ▁in ▁eastern ▁France ). ▁On ▁the ▁night ▁of ▁ 3 / 4 ▁July ▁ 1 9 4 3 , ▁along ▁with ▁other ▁resistance ▁members ▁seriously ▁damage ▁a ▁number ▁of ▁locomot ive ▁engines , ▁several ▁of ▁which ▁are ▁put ▁out ▁of ▁commission ▁for ▁several ▁months . ▁ ▁He ▁returned ▁to ▁Britain ▁once ▁again ▁in ▁a ▁L ys ander ▁on ▁ 1 7 ▁September ▁ 1 9 4 3 . ▁ ▁Four th ▁mission ▁Cow burn ' s ▁final ▁mission ▁was ▁to ▁set ▁up ▁a ▁new ▁Res istance ▁cell ▁near ▁Am iens . ▁Ar riv ing ▁by ▁par ach ute ▁on ▁ 3 0 ▁July ▁ 1 9 4 4 ▁he ▁was ▁also ▁looking ▁to ▁see ▁if ▁he ▁could ▁intercept ▁two ▁fellow ▁SO E ▁agents ▁arrested ▁by ▁the ▁Germ ans ▁( Pierre ▁M uls ant ▁and ▁John ▁Bar rett ). ▁He ▁was ▁unable ▁to ▁locate ▁the ▁agents ▁and ▁shortly ▁after ▁al lied ▁forces ▁liber