British Airways cancelled 672 flights at the end of last month due to the IT meltdown, which caused chaos for thousands of passengers.
Head of BA’s parent company IAG, Willie Walsh, told an aviation summit in Mexico this week that power to the servers was disconnected and its resumption in an “uncontrolled uncommanded fashion” led to their damage.
BA has ordered an internal investigation into how it happened and why back-up servers failed.
In a statement, the airline said: “On May 27, British Airways was affected by a power failure leading to severe disruption to flights.
“The airline cancelled 479 flights (59 per cent of operations) on that day and 193 flights (23 per cent of operations) on 28 May.
“By 29 May, the airline was flying the vast majority of its schedule. An independent investigation will examine every aspect of the power failure. British Airways is working hard to compensate affected passengers as quickly as possible.”
Walsh said BA’s communications had been poor after the incident, in which thousands of passengers were stranded at Heathrow before having to queue to leave the airport. “I wouldn’t suggest for one minute we got communications right at BA – we didn’t.”
He added: “It’s damaged us, but it hasn’t destroyed us in any way. We’ve recovered from worse. The BA brand is incredibly resilient.”
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