San Francisco drew many people, especially African Americans from the South, to the area. After the end of the war, many military personnel returning from service abroad and civilians who had originally come to work decided to stay. The United Nations Charter creating the United Nations was drafted and signed in San Francisco in 1945 and, in 1951, the Treaty of San Francisco officially ended the war with Japan. Urban planning projects in the 1950s and 1960s involved widespread destruction and redevelopment of west-side neighborhoods and the construction of new freeways, of which only a series of short segments were built before
International Civil Aviation Organization convention, held in London in 1912 allocated the first radio callsigns for use by aircraft. ICAN continued to operate until 1945. Fifty-two countries signed the Chicago Convention on International Civil Aviation, also known as the Chicago Convention, in Chicago, Illinois, on 7 December 1944. Under its terms, a Provisional International Civil Aviation Organization (PICAO) was to be established, to be replaced in turn by a permanent organization when 26 countries ratified the convention. Accordingly, PICAO began operating on 6 June 1945, replacing ICAN. The 26th country ratified the Convention on 5 March 1947 and, consequently PICAO was disestablished on 4