located many of its observation and data collection points on RAF stations. World War II technology In the 1930s, the Air Ministry commissioned a scientific study of propagating electromagnetic energy which concluded that a death ray was impractical but detection of aircraft appeared feasible. Robert Watson-Watt demonstrated a working prototype and patented the device in 1935 (British Patent GB593017). The device served as the base for the Chain Home network of radars to defend Great Britain. By April 1944, the ministry's air Intelligence branch had succeeded in its intelligence efforts regarding "the beams, the Bruneval Raid, the Gibraltar barrage, radar, Window, heavy water, and the German nightfighters" (R.V. Jones). Other World War II technology and warfare efforts included the branch's V-1 and V-2 Intelligence activities. Abolition In 1964 the Air Ministry merged with the Admiralty and the War Office to form the Ministry of Defence. See also Secretary of State for Air References External links Search and download Air Ministry Combat Reports, 1939–1945 from The National Archives. History of the Royal Air Force 1918 establishments in the United Kingdom 1964 disestablishments in the United Kingdom Defunct departments of the Government of the United Kingdom Aviation organisations based in the United Kingdom Ministries established in 1918 United Kingdom in World War II Military history of the United Kingdom during World War II Ministries disestablished in 1964 Defunct organisations based in London