Operational instruments of the Royal Observer Corps
The Royal Observer Corps (ROC) was a civil defence organisation operating in the United Kingdom between 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; a serving RAF Air Commodore.
Royal Observer Corps
These 'garden shed' style observation posts were eventually replaced by more substantial brick-built structures, protected by sandbags, which due to their often having been constructed by Observer Corps personnel themselves meant that no two posts were identical. Observation posts were located in open playing fields, hilltops or cliff edges and, particularly in urban areas, on the rooftops of public buildings and factories. Purpose-built observation posts introduced later were usually two-storey structures, constructed of brick or concrete with an open-topped observation platform above a small crew rest area. (These 1940s-era posts are sometimes incorrectly referred to as 'Orlit' posts; a term correctly associated with 1950s-era, pre-cast concrete aircraft observation posts, manufactured by "Orlit Ltd").