 The tactics proved successful in the Canadian Wing . Johnson scored his 19 — 21 victories on 23 and 26 August , whilst claiming yet another Fw 190 on 4 September 1943 . Johnsons 19th victory was gained against Oberfeldwebel ( First @-@ Sergeant ) Erich Borounik 10 . / JG 26 , who was killed . Johnson 's 21st victim , Oberfeldwebel Walter Grunlinger 10 . / JG 26 , was also killed . 
