British Airways is the flag carrier airline of the United Kingdom and its largest airline based on fleet size, international flights and international destinations. When measured by passengers carried it is second-largest, behind easyJet. The airline is based in Waterside near its main hub at London Heathrow Airport. A British Airways Board was established by the United Kingdom government in 1972 to manage the two nationalised airline corporations, British Overseas Airways Corporation and British European Airways, and two smaller, regional airlines, Cambrian Airways, from Cardiff, and Northeast Airlines, from Newcastle upon Tyne. On 31 March 1974, all four companies were merged to form British Airways. After almost 13 years as a state company, British Airways was privatised in February 1987 as part of a wider privatisation plan by the Conservative government. The carrier soon expanded with the acquisition of British Caledonian in 1987, Dan-Air in 1992 and British Midland International in 2012. British Airways is a founding member of the Oneworld airline alliance, along with American Airlines, Cathay Pacific, Qantas, and the now defunct Canadian Airlines. The alliance has since grown to become the third-largest, after SkyTeam and Star Alliance. British Airways merged with Iberia on 21 January 2011, formally creating the International Airlines Group (IAG), the world's third-largest airline group in terms of annual revenue and the second-largest in Europe.