Royal Observer Corps
In 1929 the control of the Observer Corps passed from the county police forces to the Air Ministry, although Chief Constables retained responsibility for personnel and recruitment matters. 1 March 1929 saw the establishment of the new "Headquarters of the Observer Corps" at Hillingdon House, RAF Uxbridge in the west of London, and Air Commodore Edward A D Masterman CB CMG CBE AFC RAF (Rtd) was appointed as the first commandant of the Observer Corps. "Air Cdre" Masterman held this appointment until his retirement on 1 March 1936, and was succeeded by Air Commodore Alfred Warrington-Morris CG CMG OBE AFC RAF (Rtd), who would lead the Observer Corps through the critical period during the Second World War which saw the RAF emerge bruised but victorious following the Battle of Britain of 1940.
Aircraft recognition
In the United Kingdom, The Royal Observer Corps (ROC) was formed as a defence warning organisation with civilians trained in aircraft recognition and operated primarily as such between 1925 and 1957. Aircraft recognition was first developed between the First and Second World wars when aerial warfare was first recognised as a future threat, after 208 Zeppelin and 435 aircraft raids over London during the First World War. In 1917 Germany had started using fixed-wing bombers, and the number of airship raids diminished rapidly.