The Commandos on Campbeltown now disembarked : two assault teams , five demolition teams with their protectors and a mortar group . Three demolition teams was tasked with destroying the dock pumping machinery and other installations associated with the dry dock . The kilt @-@ wearing Captain Donald Roy - ' The Laird ' - and his 14 @-@ man assault troop was tasked with inactivating two pump @-@ house roof @-@ top gun emplacements high above the quayside and securing a bridge to provide a route for the raiding parties to exit the dock area . Roy and Sgt Don Randall used scaling ladders and grenades to accomplish the former , and a head @-@ on rush to secure the bridge and form a bridgehead that enabled Capt. Bob Montgomery and Lt Corran Purdon and their demolition teams to exit the area .