The Heyford I entered service with No. 99 Squadron RAF, at RAF Upper Heyford in November 1933,[REF] and later with No. 10 Squadron and 7 Squadron, re-equipping with the Heyford IA and II in August 1934 and April 1935 respectively [REF].
The Heyford started to be replaced in 1937, with the arrival in service of Armstrong Whitworth Whitleys and Vickers Wellesleys,[REF] finally being retired from frontline service in 1939.