 After he returned, Lützow claimed three more I-15s shot down, one on 22 May, another on 28 May, and his last on 18 August 1937.His final aerial victory in Spain was over a Polikarpov I-16, a monoplane fighter aircraft, which he shot down on 22 August 1937.On 16 October 1937, Lützow was assigned to the "Reichsluftfahrtministerium" (RLM—Ministry of Aviation) "Sonderstab W." (special staff "W") under the command of and named after General Helmuth Wilberg.