July 2001: Controversial part-privatisation of the industry, as the government sells 46% of National Air Traffic Services (NATS) to The Airline Group - a consortium of seven airlines including British Airways (BA).

11 Sept 2001: World Trade Center attacks cause downturn in air travel.

Staff have complained of being overworked

20 Sept 2001: BA announces 7,000 job cuts.

26 Jan 2002: A new �623m "state-of-the-art" air traffic control centre in Swanwick, Hampshire, opens six years late. It will handle air traffic over England and Wales, taking over from two centres in Middlesex and Manchester.

13 Feb 2002: BA announces a further 5,800 job cuts.

20 Feb 2002: The UK Government is forced into an emergency bail-out, with a loan of �60m - half from the state and half from banks. It blames the post-11 September downturn, not privatisation.

10 April 2002: For the second time in a fortnight a computer handling flight data breaks down, temporarily grounding planes. Controllers are forced to use pen and paper to track the aircraft, but hundreds of flights are delayed.

16 May 2002: The low-cost airline, Easyjet, announces the purchase of rival Go for �374m, making it the biggest low-cost airline in Europe.

17 May 2002: Thousands of passengers are stranded at airport terminals across the UK after a computer failure at Swanwick causes chaos to flight schedules.

Some staff said the screens were hard to read

23 May 2002: Staff complain that text on the computer screens in Swanwick is too small to read and causes them to misread altitudes.

13 June 2002: Air traffic controllers are increasingly complaining that safety could be compromised because they are too busy.

14 June 2002: Staff overwhelmingly reject a pay deal offered by Nats of 6% over two years - talks are continuing.

18 June 2002: Pilots working for some low-cost airlines are accused of "disobeying instructions" from air traffic controllers because of pressures to avoid flight delays.