Economy of London project is construction of 42 km (26 mi) of new tunnels connecting stations in central London including a branch to Canary Wharf in east London. It is Europe's biggest construction project with a £15 billion projected cost. An additional line, Crossrail 2, has been proposed. London is served by six international airports which are the world's busiest city airport system by passenger traffic. These are Heathrow, Gatwick, Stansted, Luton, London City, and Southend. There are a number of proposals for expanding airport capacity for London including expansion of London Heathrow Airport and expansion of Gatwick Airport. The principal argument in
London International Airport Station London opened in 1950 to support a NATO Induction and Training Centre, later moved to Centralia. The station closed on 30 September 1958. As a tribute to this period, a Canadair T-33 aircraft in former Royal Canadian Air Force livery is mounted in front of the main terminal building. The airport has been continuously improved since World War II as navigation and air traffic control systems evolved, and as commercial aircraft became larger and larger. These improvements include: London International Airport Fire Crash and Rescue Station provides fire and rescue operations at the airport with three crash tenders based