Royal Observer Corps
The Royal Observer Corps (ROC) was a civil defence organisation intended for the visual detection, identification, tracking and reporting of aircraft over Great Britain. It operated in the United Kingdom between 29 October 1925 and 31 December 1995, when the Corps' civilian volunteers were stood down. (ROC headquarters staff at RAF Bentley Priory stood down on 31 March 1996). Composed mainly of civilian spare-time volunteers, ROC personnel wore a Royal Air Force (RAF) style uniform and latterly came under the administrative control of RAF Strike Command and the operational control of the Home Office. Civilian volunteers were trained and administered by a small cadre of professional full-time officers under the command of the Commandant Royal Observer Corps; latterly a serving RAF Air Commodore.
Ground Observer Corps
The second Ground Observer Corps, with programmatic aims and methodologies similar to the first, was organized in early 1950, during the Cold War. Operating as an arm of the United States Air Force Civil Defense service, the second GOC supplemented the Lashup Radar Network and the Permanent System radar stations. Observations were telephoned directly to filter centers and the information was in turn relayed to Air Defense Command ground control interception centers. By 1952 the GOC program was expanded into Operation Skywatch, consisting of 750,000 volunteers aged 7 to 86 years old working in shifts at over 16,000 posts and 73 filter centers. Extant examples of observation platforms used by GOC/Skywatch volunteers include the Cairo Skywatch Tower; another tower exists in Soda Springs, Idaho.