British Airways is the UK's largest international scheduled airline and the largest operator at Heathrow. As the UK's premier international hub airport, Heathrow plays a central - and unique - role in UK plc. Terminal 5, opened in March 2008 at a cost of £4.3 billion, is a state-of-the-art world leading facility capable of handling 30 million passengers annually. Home to some 92% of British Airways' Heathrow flights, BAA and British Airways have worked in partnership to improve the environmental performance of the airport's ground handling operation.