British Airways passengers face thousands of flight cancellations next month because of the pilot strikes expected to be announced today.

The 3,000 BA pilots are believed to have voted overwhelmingly in favour of industrial action in a dispute over the company’s plan to create a subsidiary airline with cheaper operating costs.

The earliest date a strike could be called is March 1 and families travelling on Easter holidays may also be affected. But the British Air Line Pilots’ Association was considering last night whether to avoid Easter in an attempt to win some public sympathy.

The new airline, called Open Skies, is supposed to start flying between continental cities and the United States this summer. Balpa is concerned that Open Skies pilots could be paid less and that they could be used to reduce the pay and conditions of flight crew at the main airline.

Thousands of BA passengers missed their flights from Terminal 4 Heathrow yesterday after a baggage system failure. The computer software glitch began on Tuesday and took more than 24 hours to fix.

This meant that economy and premium economy passengers were unable to check any luggage into the hold. BAA, the airport operator responsible for the baggage system, said it was confident that services would be back to normal today.

Almost 50 Heathrow flights, mainly BA flights to European destinations, were cancelled yesterday because of fog. BA also announced yesterday that it was increasing its fuel surcharges for long-haul flights because of the high oil price.

The surcharge for long-haul flights of less than nine hours will rise next Monday, February 25, from £96 for a return flight to £106.

BA said that the surcharge on return long-haul flights of more than nine hours would increase from £116 to £128. It said that there would be no change to the short-haul flight surcharge, which will remain at £20 for a return flight.

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