He went on to be Air Officer Commanding RAF Iraq in November 1926 before becoming Air Officer Commanding-in-Chief Air Defence of Great Britain in February 1929 with promotion to air marshal on 1 July 1929.
He went on to be Air Officer Commanding RAF Iraq in November 1926 in which role he undertook peace keeping operations following action by Sheikh Mahmud Barzanji in 1927. Ellington became becoming Air Officer Commanding-in-Chief Air Defence of Great Britain in February 1929 with promotion to air marshal on 1 July 1929.