▁U - bo ats ▁on ▁three ▁occasions ▁– ▁the ▁first ▁escaped ; ▁the ▁second ▁struck ▁a ▁mine ▁when ▁purs ued ; ▁and ▁under ▁the ▁command ▁of ▁Major ▁G . ▁M . ▁Thomas ▁on ▁ 2 9 ▁September ▁ 1 9 1 8 ▁she ▁attacked ▁a ▁third , ▁U B - 1 1 5 ▁about ▁ ▁n ortheast ▁of ▁Be acon ▁Point , ▁Newton - by - the - Se a , ▁off ▁North umber land . ▁During ▁the ▁attack , ▁in ▁which ▁R 2 9 ▁was ▁joined ▁by ▁armed ▁tra w lers ▁and ▁the ▁destroy ers ▁HMS ▁O use ▁and ▁Star , ▁she ▁dropped ▁two ▁ ▁bomb s . ▁ ▁Int elligence ▁reports ▁subsequently ▁confirmed ▁that ▁the ▁sub marine ▁had ▁been ▁destroyed ▁in ▁the ▁attack ▁– ▁the ▁only ▁recorded ▁success ▁by ▁any ▁British ▁w art ime ▁rig id ▁air ship . ▁ ▁R 2 9 ▁fle w ▁another ▁ 1 6 ▁hours ▁after ▁the ▁Arm ist ice , ▁and ▁in ▁May ▁ 1 9 1 9 ▁her ▁mid ship ▁car ▁was ▁replaced ▁by ▁a ▁smaller ▁and ▁l ighter ▁type ▁containing ▁just ▁one ▁engine ▁driving ▁a ▁single ▁prop eller . ▁She ▁subsequently ▁fle w ▁a ▁further ▁ 8 7 ▁hours ▁including ▁an ▁extended ▁flight ▁over ▁Scotland ▁accompanied ▁by ▁R 3 4 , ▁and ▁was ▁finally ▁deleted ▁in ▁October , ▁ 1 9 1 9 . ▁She ▁covered ▁an ▁estimated ▁ ▁in ▁service , ▁more ▁than ▁any ▁previous ▁British ▁rig id ▁air ship . ▁ ▁Oper ators ▁ ▁Royal ▁Naval ▁Air ▁Service ▁/ ▁Royal ▁Air