At the outbreak of the Second World War, Croome Court and its surrounding estate was requisitioned by the Ministry of Works. The main palladian house was initially leased for a year to the Dutch Government as a possible refuge for Queen Wilhelmina of the Netherlands to escape the Nazi occupation of the Netherlands. However, evidence shows that they only stayed for two weeks at most, and later emigrated to Canada. Construction of RAF Defford was started at the outbreak of war, and completed in 1941. For a few months the airfield was used as a satellite station by the Vickers Wellington bombers of No. 23 Operational Training Unit RAF, based a few miles away at RAF Pershore. In May 1942, the Telecommunications Research Establishment, responsible for radarresearch and development, and located near Swanage, moved to Malvern College. At the same time the Telecommunications Flying Unit, later named the Radar Research Flying Unit, which operated flight trials on behalf of the TRE, transferred its aircraft to Defford. So hurried was the move to Defford that many of the personnel had to be accommodated in tents at first. However, at Defford the tempo of work carried out by TFU increased month by month, and by 1945 there were approximately 2,500 personnel and 100 aircraft on the station. Civilian scientists, flying from Defford with aircrews drawn from the Royal Air Force and Royal Navy, tested radar systems which were to revolutionise the operational capability of Allied aircraft. Early successes with Airborne Interception systems were demonstrated by John "Cats Eyes" Cunningham and other night fighter pilots. While Air to Surface Vessel radar enabled the German U-boat menace to be effectively countered in 1943, and thus was critical to the success of the Battle of the Atlantic. By 1944, H2S radar was enabling accurate navigation and target identification to be achieved by Bomber Command crews, taking part in the strategic bombing offensive. No. 1001 Signals Unit RAF and the Special Installation Unit RAF were also here at some point. Village Inn FN121 tail turret as fitted on a Lancaster test flown from RAF Defford. There were many other notable "firsts" demonstrated by TFU. A converted Wellington bomber was the forerunner of the modern AWACS aircraft. This was successfully used to detect fast moving German E-boats, and to control their interception by other aircraft. The world's first automatic approach and landing also took place at Defford in 1945, paving the way for today's airliners which are able to safely arrive at their destinations, whatever the weather. The world's first demonstration of an aircraft making a "hands off" automatic blind landing, using equipment the forerunner of modern ILS, was at Defford in January 1945.
Postwar use
TFU remained at Defford after the war, and was renamed the Radar Research Flying Unit in 1953. However, the airfield at Defford was too small to allow the operation of the large "V" bombers on flight trials, and so RRFU moved to nearby RAF Pershore in 1957. Most of the technical and domestic sites at Defford were soon de-requisitioned, but the central part of the now disused airfield still houses the Satellite Communications facility operated by QinetiQ. The various dishes and aerials used can be seen from passing trains between Worcester and Cheltenham and from the M5 motorway near Strensham services.
Current use
The airfield site is now owned and used by the West Mercia Constabulary and many of the "golf balls" and other communications equipment have been removed. Some of the station buildings remain in other uses. A few are contained within the National Trust property of Croome, including part of the station’s medical facilities which now house the RAF Defford museum.
Accidents and incidents
The worst accident in the history of the unit happened on when Handley Page HalifaxV9977 crashed on 7 June 1942 with the loss all eleven crew and scientists on board including Alan Blumlein. It had been testing the new H2S radar system that used the cavity magnetron valve developed by TRE. In 2002, exactly sixty years later, an RAF Defford Memorial was unveiled by Sir Bernard Lovell on the village green of Defford. It commemorates those who lost their lives in accidents while carrying out scientific research. It reads:
