Area 51 between Area 51 and Lockheed's Burbank, California offices. To preserve secrecy, personnel flew to Nevada on Monday mornings and returned to California on Friday evenings. Project OXCART established in August 1959 for "antiradar studies, aerodynamic structural tests, and engineering designs [and] all later work on the" Lockheed A-12 included testing at Groom Lake, which before improvements for OXCART had inadequate facilities: buildings for only 150 people, a asphalt runway, and limited fuel, hangar, and shop space. Selected for its seclusion and climate, Groom Lake had received a new official name "Area 51" when A-12 test facility construction began in September
North American P-51 Mustang variants for the P-51 came from tests carried out at facilities such as the USAAF's "Flight Test Engineering Branch", based at Wright Field near Dayton, Ohio and, for the RAF, the Aeroplane & Armament Experimental Establishment (A&AEE), based at Boscombe Down. North American Aviation carried out their own performance tests, as did the only other manufacturer of the P-51, the Commonwealth Aircraft Corporation (CAC) of Australia. North American P-51 Mustang variants Over twenty variants of the North American P-51 Mustang fighter were produced from 1940, when it first flew, to after the Second World War, some of which were employed also