RAF Medmenham

Royal Air Force Medmenham
Part of Royal Air Force
Near Medmenham, Buckinghamshire, England
Danesfield House, the war time home of RAF Medmenham
Coordinates	51°33′11″N 0°49′26″W / 51.553°N 0.824°W / 51.553; -0.824Coordinates: 51°33′11″N 0°49′26″W / 51.553°N 0.824°W / 51.553; -0.824
Type	Air Force Base
Site history
In use	1941-1977
Garrison information
Past commanders	Peter Stewart, Francis Cator, Douglas Kendall
Occupants	Allied Central Interpretation Unit

RAF Medmenham was a Royal Air Force station based at Danesfield House near Medmenham, in Buckinghamshire, England. Activities there specialized in photographic intelligence, and it was once the home of the RAF Intelligence Branch. During the Second World War, RAF Medmenham was the main interpretation centre for photographic reconnaissance operations in the European and Mediterranean theatres.

In April 1941, an RAF photographic interpretation unit (PIU) moved to Danesfield House, Medmenham, as its previous location at Wembley was short of space, and was renamed the Central Interpretation Unit (CIU). Later that year the Bomber Command Damage Assessment Section was absorbed, and amalgamation was completed when the Night Photographic Interpretation Section of No 3 Photographic Reconnaissance Unit, RAF Oakington, was integrated with CIU in February 1942.

During 1942 and 1943, the CIU gradually expanded and was involved in the planning stages of practically every operation of the war, and in every aspect of intelligence. In 1945, daily intake of material averaged 25,000 negatives and 60,000 prints. By VE-day, the print library, which documented and stored worldwide cover, held 5,000,000 prints from which 40,000 reports had been produced.

American personnel had for some time formed an increasing part of the CIU and on 1 May 1944 this was finally recognised by changing the title of the unit to the Allied Central Interpretation Unit (ACIU). There were then over 1,700 personnel on the unit's strength. The title of the unit reverted to Central Interpretation Unit when the Americans returned home in August 1945.

Early in 1945, a number of photographic interpreters (PIs) were sent to join the British Bombing Research Mission in Paris to explore the degree of damage and production interruption caused by Allied bombing in the Resistance areas of the Massif Central and in the ports. They were also tasked with checking PI reports which were eventually related to assessment reports of attacks on German industry. Several PIs were also seconded to the Pentagon in Washington, D.C., to join a detachment of RAF and British Army officers.