Planned as an RAF operational training base, Membury was built during 1942, and then upgraded in 1943 after allocation to the USAAF as a reconnaissance or transport base, with maintenance and repair depot facilities. It had eventually three concrete runways, 26 loop and 25 pan hardstandings, two T2 hangars on the airfield site and two T2 hangars in the depot area. Claimed by VIII Ground Air Support Command, later Ninth Air Force HQ, the station was first occupied briefly during September to October 1942 by men of the 3rd Photographic Group without aircraft. The 67th Observation Group also arrived in September 1942, initially without aircraft so operated Spitfires, Havocs and Bostons loaned by the RAF plus a few L-4Bs. Transferred to the Ninth Air Force in October 1943, while re-equipping with P-51s, the group was renamed the 67th Tactical Reconnaissance Group and moved to Middle Wallop in November 1943. During November 1943 to August 1944, the air depot site was occupied by the 7th and 16th Air Depot Groups, forming the 6th Tactical Air Depot which specialised in the repair and modification of P-47s. The 366th Fighter Group was resident briefly during January-February 1944 while equipping with P-47s, and the station was then occupied by the 436th Troop Carrier Group, equipped with C-47s, from March 1944 to February 1945. It was also used by other transport units from June 1944 to June 1945 as a supply delivery and collection point. Returned to the RAF as a transport base in June 1945, the station remained operational until 1946. Partly returned to agriculture since the 1950s, small industries took over many of the wartime buildings which continue as Membury Business Park. The airfield remained open as a private airport and, although restricted by construction of the M4 motorway, continues in limited use as Membury Airfield.