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.
Royal Observer Corps
In 1950, King George Vl granted permission for the issue of a "Royal Observer Corps Medal" for twelve years continuous service. Each subsequent period of twelve years was recognised by the award of an RAF "eagle clasp" attached to the medal ribbon. Service by full-time officers was calculated at a rate of 50% for qualifying years, thereby requiring fully twenty four years service in order to qualify for a medal or subsequent clasp. However, any spare-time service previously undertaken by such individuals counted in full. (ROC personnel who served for 28 days during World War II also qualified for the award of a War Medal, with service of 1,080 days qualifying for the 1939–1945 Star and the Defence Medal).