Media playback is unsupported on your device Media caption Queues at Heathrow airport stretched out of the terminal

Serious problems with British Airways' IT systems have led to thousands of passengers having their plans disrupted, after all flights from Heathrow and Gatwick were cancelled.

Passengers described "chaotic" scenes at the airports, with some criticising BA for a lack of information.

The airline has apologised, and told passengers not to come to the airport.

BA chief executive Alex Cruz said: "We believe the root cause was a power supply issue."

In a video statement released via Twitter, he added: "I am really sorry we don't have better news as yet, but I can assure you our teams are working as hard as they can to resolve these issues."

Mr Cruz said there was no evidence the computer problems were the result of a cyber attack.

The airline hoped to be able to operate some long haul inbound flights on Saturday, landing in London on Sunday, Mr Cruz added.

The GMB union has suggested the failure could have been avoided, had the airline not outsourced its IT work.

BA denied the claim, saying: "We would never compromise the integrity and security of our IT systems".

All passengers affected by the failure - which coincides with the first weekend of the half-term holiday for many in the UK - will be offered the option of rescheduling or a refund.

The airline, which had previously said flights would be cancelled until 18:00 BST, has now cancelled all flights for Saturday and asked passengers not to come to Gatwick or Heathrow airports.

Other airlines flying in and out of the two airports are unaffected.

Architect and TV presenter George Clarke was stuck in Heathrow. He told the BBC it was one of the "most turbulent, badly organised days, that I've ever experienced in Britain".

"The lack of communication all day was woeful. There wasn't a single Tannoy announcement all day in the terminal, not a single member of staff came up to us," he said.

"The only time I found out my flight was cancelled was from the BBC News website."

Image copyright @AnnaOnTheWeb Image caption Piles of checked luggage could be seen on the floor in the Heathrow

Image caption Some passengers have reported having to leave Heathrow without their luggage

The problems have affected BA call centres, the website and the mobile app.

Aviation expert Julian Bray said: "It's frozen the whole system so no British Airways plane can actually take off, they can't move the baggage, they can't issue passenger credentials, in fact they can't do anything at all.

"This is a very serious problem, they should have been able to switch to an alternative system - surely British Airways should be able to do this."

Malcolm Ginsberg, editor in chief at Business Travel News, expects the disruption to last for "three or four days".

BA aircraft landing at Heathrow are unable to park as outbound aircraft cannot vacate the gates, which has resulted in passengers being stuck on aircraft.

Journalist Martyn Kent said he had been sitting on a plane at Heathrow for 90 minutes. He said the captain told passengers the IT problems were "catastrophic".

'Catastrophic'

Mick Rix, GMB's national officer for aviation said: "This could have all been avoided.

"BA in 2016 made hundreds of dedicated and loyal IT staff redundant and outsourced the work to India... many viewed the company's actions as just plain greedy."

BA staff in Heathrow's Terminal 5 were resorting to using white boards, according to passenger Gareth Wharton.

Delays have been reported in Rome, Prague, Milan, Stockholm and Malaga due to the system failure.

Philip Bloom said he had been waiting on board a Heathrow-bound flight at Belfast for two hours.

He added: "We haven't been told very much just that there is a worldwide computer system failure.

"We were told that we couldn't even get on other flights because they are unable to see what flights we can be moved to."

Analysis - By Richard Westcott, BBC transport correspondent

Image copyright @theboyg Image caption With a lack of technology, staff were using whiteboards in Heathrow

As ever, it is a lack of information that is really making BA passengers angry… we're still awaiting an explanation from the airline and a timescale for how long the problems might last.

The GMB union says this meltdown could have been avoided if BA had not made hundreds of IT staff redundant and outsourced their jobs to India at the end of last year.

Yes, the union has a big axe to grind, but people will want to know if the airline made its IT systems more vulnerable by scaling back computer support to save money - although BA has just flatly denied it to me.

IT problems ripple through an airline. If planes cannot take off, they cannot leave gaps at the gate for others to land.

If flights are delayed by more than around five hours, the airline must swap crews because shift lengths are strictly limited for safety reasons.

Telling customers to stay away is a drastic measure, but it is the only chance BA has of clearing the backlog of flights.

Image copyright Twitter

The BBC's Phillip Norton was at Rome international airport, waiting to fly to London.

He said BA staff were unable to say how long delays would be, telling him "all flights are grounded around the world".

Alma Saffari was in Marseille waiting to get her flight back to Heathrow.

She said: "When we finally boarded the captain came out and told us their computer systems were down worldwide.

"Eventually after sitting on the tarmac for one and a half hours we disembarked the plane.

"Now we are sitting in the departure area outside the gate."

Ms Saffari, who is with her 13-month-old baby, said she had been given a voucher for food and drink.

EU flight delay rights

Image copyright @TimReidCE Image caption Passengers have experienced large queues and disruption at Heathrow Terminal 5, British Airways' main London terminal</s>British Airways has cancelled all flights from Gatwick and Heathrow as computer problems cause disruption worldwide.

Passengers have been told not to travel to the London airports because of “extreme congestion” at the terminals, with all BA planes grounded before 6pm on Saturday.

A spokeswoman for the airline said: “We have experienced a major IT system failure that is causing very severe disruption to our flight operations worldwide.”

“The terminals at Heathrow and Gatwick have become extremely congested and we have cancelled all flights from Heathrow and Gatwick before 6pm UK time today, so please do not come to the airports,” the airline continued.

“We are extremely sorry for the inconvenience this is causing our customers and we are working to resolve the situation as quickly as possible.”

Travellers have been told to check the airline website and twitter account for updates about the situation.

Heathrow Airport has been affected by the issue and advised passengers to check their flight status before travelling to the airport.

A spokesman said on Twitter: “We’re working with @British_Airways following an issue with their IT system this morning that has caused some delays for passengers.

“We advise passengers to check the status of their flight prior to travelling to the airport today.”</s>British Airways has resumed some flights from Britain’s two biggest airports after a global computer system failure, but thousands of travellers face further chaos with about 40 flights cancelled from London’s Heathrow Airport.

About one quarter of Sunday’s flights set to depart from London’s key hub before 1.00 pm (1200 GMT) were cancelled as the airline battled to contain the “knock-on disruption” to schedules, with aircraft and crews out of position around the world.

British Airways said it was hoping to operate a near-normal schedule of flights from Gatwick, London’s other major airport, and the majority of its Heathrow services.

More flights left Heathrow as the day wore on, but most were operating with delays. Travellers also faced hold-ups at Gatwick, but no flights were cancelled.

The airline advised passengers not to come to the two airports unless they had confirmed bookings, with disruption expected throughout the holiday weekend.

Monday is a public holiday and many children were starting a one-week school holiday.

Some passengers were curled up under blankets on the floor or sleeping slumped on luggage trolleys. Several passengers complained about a lack of information from BA representatives at the airport. Others said their luggage had been lost.

“Everyone is upset. There’s people in tears,” said Melanie Ware, who flew in from Los Angeles and was trying to get to Venice on her honeymoon.

“We rebooked for Venice for tonight, which they also have cancelled now,” she told Sky News.

“So we have no way of getting out of Heathrow and they haven’t compensated us for anything, and we’re stuck and this is the worst honeymoon ever.

BA cancelled all its flights out of Heathrow and Gatwick on Saturday after the IT failure, which shut down all of the carrier’s check-in and operational systems and affected call centres and its website.

“We believe the root cause was a power supply issue,” said Alex Cruz, the chairman and chief executive of BA, adding that IT teams were working “tirelessly” to fix the problems.

Full refunds will be given to customers who decide they no longer wish to travel, Cruz said.

While other airlines have been hit by computer problems, the scale and length of BA’s troubles were unusual.

Delta Air Lines Inc cancelled hundreds of flights and delayed many others last August after an outage hit its computer systems.

Last month, Germany’s Lufthansa and Air France suffered a global system outage which briefly prevented them from boarding passengers.

Now read: British Airways flights cancelled due to IT system failure</s>British Airways said it had canceled all flights from London’s Heathrow and Gatwick airports scheduled before 1700 GMT on Saturday due to a global computer outage.

“We have experienced a major IT system failure that is causing very severe disruption to our flight operations worldwide,” the airline said in a statement.

Because of the blackout, British airways says that flights were delayed on Saturday, with passengers reporting massive hold-ups at airports and planes being held on runways.

The problems, which passengers said were affecting flights across the country, came on a particularly busy weekend in Britain with a public holiday on Monday and many children starting their school half-term breaks.

“We apologize to customers who are facing some delays following an IT outage this morning,” a BA spokeswoman said. “We are working to resolve the problem as quickly as possible.”

She gave no further details. Passengers on social media reported long delays at check-in desks and flights being held on runways.

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“Still on the tarmac at Leeds. #britishairways reckon Heathrow is so backed up we can’t set off. No way we’ll make our Vegas flight,” one passenger David Raine wrote on Twitter.

Another, journalist Martyn Kent, wrote: “Sat on plane at Heathrow for hour and a half now. @British_Airways Captain describes IT problem as ‘catastrophic’.”

London’s Heathrow Airport, one of the world’s busiest, said it was working with BA and advised passengers to check their flight status before traveling.

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Passenger Roshni Burt, who was flying from Heathrow to Bahrain with her young son, said there was no news about when her flight would depart.

“When we left the check-in area there were angry people, people getting frustrated that their flights were coming up or near to departure, people getting turned away … with BA staff basically saying ‘if you’ve not checked in online, you’ve missed your flight’,” she told Sky News.

BA is the latest airline to be hit by computer problems. Last month Lufthansa and Air France suffered a global system outage which prevented them from boarding passengers.</s>British Airways has cancelled all its afternoon Gatwick flights and is telling customers not to come to the airport.

The airline has cancelled all flights from Gatwick and Heathrow before 6pm, blaming a ‘major IT system failure’.

Customers are being advised not to go to the airports.

A British Airways spokesman said: “We have experienced a major IT system failure that is causing very severe disruption to our flight operations worldwide.

“The terminals at Heathrow and Gatwick have become extremely congested and we have cancelled all flights from Heathrow and Gatwick before 6pm today.

“Please do not come to the airports.”

Travellers are advised to keep checking their flight status throughout the day.</s>British Airways have cancelled all flights scheduled to depart from Heathrow and Gatwick today.

A major IT failure has caused extensive delays and disruption to the airline's operations worldwide.

The IT issue comes as thousands plan to jet out of the UK this Bank Holiday weekend and for the start of half term.

British Airways tweeted to apologise to customers for the delays and said 'we are working to resolve the problem as quickly as possible.'

Passengers have been asked not to travel to the London airports because of "extreme congestion" at the terminals.

BA staff were handing out letters to the passengers stranded at these airports. The letters apologised for the cancellations and gave details about how to claim for hotels, local transport and refreshments.

A spokeswoman for the airline said: "We have experienced a major IT system failure that is causing very severe disruption to our flight operations worldwide."

"We've found no evidence that it's a cyber attack."

The airline added: "The terminals at Heathrow and Gatwick have become extremely congested and we have cancelled all flights from Heathrow and Gatwick before 6pm UK time today, so please do not come to the airports.

"We are extremely sorry for the inconvenience this is causing our customers and we are working to resolve the situation as quickly as possible."

Have your travel plans been affected by this? Let us know by commenting below</s>British Airways has cancelled all flights from Gatwick and Heathrow as computer problems cause disruption worldwide.

Passengers have been told not to travel to the London airports because of “extreme congestion” at the terminals, with all BA planes grounded before 6pm on Saturday.

A spokeswoman for the airline said: “We have experienced a major IT system failure that is causing very severe disruption to our flight operations worldwide.”

“The terminals at Heathrow and Gatwick have become extremely congested and we have cancelled all flights from Heathrow and Gatwick before 6pm UK time today, so please do not come to the airports,” the airline continued.

“We are extremely sorry for the inconvenience this is causing our customers and we are working to resolve the situation as quickly as possible.”

Travellers have been told to check the airline website and twitter account for updates about the situation.

Heathrow Airport has been affected by the issue and advised passengers to check their flight status before travelling to the airport.

A spokesman said on Twitter: “We’re working with @British_Airways following an issue with their IT system this morning that has caused some delays for passengers.

“We advise passengers to check the status of their flight prior to travelling to the airport today.”

Teacher Gemma Richardson, 30, who is 24 weeks pregnant, was travelling with her husband David, 30, and their two-year-old daughter to Spain.

Mrs Richardson, who was sitting uncomfortably on a barrier, said “it was chaos” when they arrived at the airport.

She said: “There was no formal guidance, just information on a screen saying that the flights up to 6pm had been cancelled.

“We all pooled around a BA employee who was doing her best to give advice.

“It seems that because it is a bank holiday weekend there is no spare flights. We are on standby but it is very unlikely we are going anywhere.

“It is all stressful but we are trying to put a best face on it for my daughter but it is very difficult.

“There are no real chairs here so I am sitting on a barrier which is not great.”

Linda Murakami, 55, had flown in from her home in Pennsylvania, US, for a connecting flight to Naples, Italy, only to find it had been cancelled.

She is now cancelling a “dream holiday” to the Amalfi coast with her family.

Miss Murakami, who retired early from a pharmaceutical company, said: “This trip was my retirement present.

“There are a lot of other things that can cause disappointment and could put everyone in a worse situation.

“We just have to be flexible. We have travel insurance so feel that because we would miss part of the vacation, we might as cancel it and just go again at a different time. For me, it is an inconvenience.”

Her friend Joyce Cohen, of New Jersey, said: “This had been my dream vacation. Everything had been worked out so that I could come. I am very upset.

“I have waited for this my whole life and I am not in good health, so who knows what could happen by next year when I could come again.”

Malcolm Ginsberg, editor in chief at Business Travel News, said: “This is a very, very serious situation, one that will not be solved overnight, even once they get the technology aspects of it done - it’s going to be three or four days.

“There’s only full aircraft at this time of year and there will be aircraft in the wrong positions.

“Of course I feel sorry for the passengers but for the staff as well who have got to deal with it all.”</s>British Airways has cancelled all its Gatwick flights for the rest of today and is telling customers not to come to the airport.

The airline has cancelled all flights from Gatwick and Heathrow today, blaming a ‘major IT system failure’.

Customers are being advised not to go to the airports.

The airline initially cancelled flights until 6pm today, but issued an update later update saying that none of their flights would leave Gatwick or Heathrow today.

A British Airways spokesman said: “We have experienced a major IT system failure that is causing very severe disruption to our flight operations worldwide.

“The terminals at Heathrow and Gatwick have become extremely congested and we have cancelled all flights from Heathrow and Gatwick.

“Please do not come to the airports.

“We are working hard to get our customers onto the next available flight over the course of the rest of the weekend.”

Customers unable to travel will be offered full refunds.</s>There was bad news for passengers jetting out of the UK for the start of the bank holiday weekend - British Airways has cancelled all flights from Gatwick and Heathrow.

A major computer problem has caused disruption to the airline's operations worldwide.

Passengers have been told not to travel to the London airports because of "extreme congestion" at the terminals, with all BA planes grounded before 6pm on Saturday.

A spokeswoman for the airline said: "We have experienced a major IT system failure that is causing very severe disruption to our flight operations worldwide."

But they later added: "We've found no evidence that it's a cyber attack."

The airline continued: "The terminals at Heathrow and Gatwick have become extremely congested and we have cancelled all flights from Heathrow and Gatwick before 6pm UK time today, so please do not come to the airports.

"We are extremely sorry for the inconvenience this is causing our customers and we are working to resolve the situation as quickly as possible."

Heathrow Airport said it was "working closely" with BA to solve the issue and advised passengers to check the status of their flight before travelling to the airport.

Travellers have been told to check the airline website and twitter account for updates about the situation.

There were reports of huge queues at check-ins.

The issues come as thousands of families - many with young children - flock abroad for the Bank Holiday weekend and the start of half term.

The airline has experienced issues with its online check-in systems in the past.

Passengers were hit by severe delays in September and July last year because of IT glitches.

The latest problem meant parts of BA's website were unavailable and some travellers were unable check in on the mobile app.</s>LONDON (AP) - The Latest on British Airways flight stalled by IT failure (all times local):

British Airways has canceled all flights from London’s Heathrow and Gatwick airports as a global IT failure causes severe disruption for travelers.

The airline says it has suffered a “major IT systems failure.”

BA says terminals at Heathrow and Gatwick have become extremely congested and it is cancelling all flights from the airports until 6 p.m. (1700GMT). It is urging passengers not to go to the airports.

Earlier, passengers at Heathrow reported long lines at check-in counters and flight delays.

BA has not said what is causing the computer problem, but says it is working to resolve it as quickly as possible.

Air travelers faced delays Saturday because of a worldwide computer systems failure at British Airways, the airline said.

BA apologized in a statement for what it called an “IT systems outage” and said it was working to resolve the problem. It said in a tweet that the problem is global.

Passengers at Heathrow Airport reported long lines at check-in counters and flight delays. One posted a picture on Twitter of BA staff writing gate numbers on a white board.

“We’ve tried all of the self-check-in machines. None were working, apart from one,” said Terry Page, booked on a flight to Texas. “There was a huge queue for it and it later transpired that it didn’t actually work, but you didn’t discover that until you got to the front.”

The problem comes on a holiday weekend, when thousands of Britons are travelling.
British Airways cancels all flights from Heathrow Airport and Gatwick Airport amid a "major IT system failure", that is causing severe disruption to flight operations worldwide.