After evaluation of two prototypes, one powered by the Bristol Lucifer and the other by the Armstrong-Siddeley Lynx, the Lynx powered aircraft was selected by the RAF to replace the 504K.
После оценки двух прототипов с двигателями Bristol Lucifer и Armstrong-Siddeley Lunx, машина с двигателем Lunx была выбрана школой пилотов RAF как замена 504K.