▁augment ed ▁by ▁a ▁third ▁member , ▁sometimes ▁referred ▁to ▁as ▁B ord me chan iker ▁( air ▁mechan ic ) ▁or ▁B ord sch üt ze ▁( air ▁gun ner ). ▁The ▁reason ▁for ▁this ▁was ▁that ▁the ▁decl ine ▁of ▁the ▁H imm el b ett ▁procedure , ▁the ▁introduction ▁of ▁the ▁broadcast ▁procedure ▁Z ah me ▁Sau , ▁and ▁the ▁growing ▁threat ▁of ▁R AF ▁intr uder ▁night ▁f ighter ▁operations , ▁had ▁necess itated ▁the ▁need ▁for ▁another ▁pair ▁of ▁watch ful ▁eyes ▁to ▁the ▁rear . ▁Unter off iz ier ▁Wilhelm ▁G ä ns ler , ▁who ▁had ▁already ▁contributed ▁to ▁ 1 7 ▁claims ▁made ▁by ▁Haupt mann ▁Ludwig ▁Be cker , ▁was ▁Sch n au fer ' s ▁new ▁look out . ▁With ▁Hand t ke ▁and ▁G ä ns ler ▁as ▁his ▁crew , ▁Sch n au fer ▁claimed ▁his ▁ 2 6 th ▁aer ial ▁victory ▁on ▁ 2 3 ▁September ▁ 1 9 4 3 ▁over ▁a ▁No . ▁ 2 1 8 ▁Squadron ▁St ir ling ▁during ▁a ▁Wil de ▁Sau ▁intercept ▁mission . ▁ ▁Following ▁its ▁May ▁ 1 9 4 3 ▁debut ▁in ▁action , ▁during ▁the ▁second ▁half ▁of ▁ 1 9 4 3 , ▁Sch n au fer ▁and ▁his ▁crew ▁began ▁experiment ing ▁with ▁up ward - f iring ▁aut oc ann ons , ▁dub bed ▁Sch rä ge ▁Musik . ▁This ▁allowed ▁the ▁night ▁f ighter ▁to ▁approach ▁and ▁attack ▁the ▁bom bers ▁from ▁below —