British Airways IT shutdown was caused by major ‘uncontrolled’ power surge after outage that wiped out check-in systems, airline claims

THE British Airways bank holiday meltdown was caused by an "uncontrollable return of power" after an outage, the airline has said.

Around 75,000 passengers had their journeys disrupted when BA's computer systems crashed.

Some were forced to pay up to £800 to get on spare premium seats to reach their destinations and many are still waiting to be reunited with their luggage.

Bosses were accused of further attempting to cash in on the chaos after BA told customers to call a premium-rate emergency phone line charging 62p a minute.

And the GMB union said the disaster could have been avoided if "hundreds" of IT jobs had not been outsourced to India last year.

But the airline said in a statement: "There was a loss of power to the UK data centre which was compounded by the uncontrolled return of power which caused a power surge taking out our IT systems.

"So we know what happened we just need to find out why."

"It was not an IT failure and had nothing to do with outsourcing of IT, it was an electrical power supply which was interrupted.

"We are undertaking an exhaustive investigation to find out the exact circumstances and most importantly ensure that this can never happen again."

BA’s chief executive Alex Cruz, who says he will not quit, earlier claimed the problem was caused by a power supply issue at a UK data centre.

But energy firms SSE and UK Power Networks, which serve Heathrow and BA’s nearby HQ, rejected that claim.

Experts predict BA is facing huge compensation costs, with reports suggesting the bill could top £100 million.

The airline said it will "comply with all of the relevant EU compensation regulations" including welfare claims such as hotel accommodation, transport to and from hotels, meals and telephone calls.

It has added extra staff to its customer relations department to help process payments.

All of the delayed bags have been processed at Heathrow and are on their way to customers around the world.

The airline accepted that "it may take some time to complete the process", particularly for passengers on complex itineraries or in locations it does not serve every day.

BA's parent company, IAG, saw shares initially fall by around four per cent in the first day of trading in London after the outage occurred.

On Saturday night, travellers spent the night sleeping on yoga mats spread on terminal floors after BA cancelled all flights leaving Heathrow and Gatwick.

A full flight schedule was up and running on Tuesday — three days after the crisis began.

The airline is now directing affected customers to call a freephone number - 0800 727 800 - and check updates on its website.

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