Johnson took command of No. 127 Wing RCAF based at RAF Kenley after Christmas and they received the new Spitfire IX: the answer to the Fw 190. After gaining a probable against a Fw 190 in February 1943, Johnnie selected Spitfire EN398 after a 50-minute test flight on 22 March 1943. It became his regular mount. Being a wing commander now meant his initials could be painted on the machine. His Spitfires now carried JE-J. He was also allotted the call sign "Greycap".