Kammala jumla mai zuwa: Da yake yana sha'awar jirgin sama tun yana yaro, Plagis ya ba da kansa ga Sojojin Sama na Kudancin Rhodesia (SRAF) jim kaɗan bayan barkewar yaƙi a watan Satumba na 1939. An ƙi shi saboda shi ɗan ɗan ƙasa ne kuma saboda haka ba ɗan ƙasa ba ne, duk da cewa ya zauna a Rhodesia duk rayuwarsa. Bayan Italiya
ya mamaye Girka a ƙarshen Oktoba 1940, yana kawo Helenawa cikin yaƙin a gefen Allied, Plagis ya sake neman - wannan lokacin don shiga Royal Air Force, wanda ya sha SRAF a watan Afrilu 1940 - kuma an karɓa. Horar da farko a Kudancin Rhodesia, sa'an nan Ingila, Plagis ya fita tare da matsayi na jirgin sama a watan Yunin 1941 tare da sama da matsakaicin matsakaicin a duk gwajin da ya tashi.