Heraldo de Madrid - Travel chaos after power outage closes London's Heathrow airport

Heathrow plies routes to 80 countries and some 1,350 flights had been due to land or take off from the airport's five terminals on Friday, according to the online flight tracking website Flightradar24.

Some 230,000 passengers a day and 83 million a year use Heathrow, making it one of the world's busiest airports.

Firefighters were called to a "highly visible" blaze at the substation at about 11:23 pm (2323 GMT) Thursday with some 70 sent to battle the fire, which was brought under control around 8:00 am.

UK Energy Secretary Ed Miliband promised that the government would do all it could to restore power to Heathrow quickly, as questions were raised about the airport's "resilience".

Videos on social media, apparently shot inside Heathrow's terminals, showed shuttered shops and deserted corridors, lit only by emergency lighting.

The shut-down left many passengers struggling to make alternative arrangements.

"I had planned this journey three months ago... I've spent so much money on tickets and everything," said Muhammad Khalil, 28, who was booked on a flight to Pakistan to be reunited with his wife after five months.

"You can't imagine how stressful it is for me," he told AFP at London's Paddington train station from where he had been due to travel to Heathrow.

British Airways said the closure of its main hub would have a "significant impact" on its operations and customers.

"We're working as quickly as possible to update them on their travel options for the next 24 hours and beyond," it said.

Talia Fokaides, 42, was supposed to leave London Friday morning for Athens, but rushed to Gatwick when she heard the news to get a new ticket.

Her mother was having open heart surgery later in the day. "I just need to be there" she told AFP, her voice shaking with emotion.

- Flights diverted -

Around 120 Heathrow-bound planes were in the air when the closure was announced, according to Flightrader24.

The UK's second busiest airport, Gatwick, said it would accept some flights from Heathrow. Others were diverted to European airports including Shannon in southwestern Ireland, Frankfurt, and Paris Charles de Gaulle.

"We are aware of the situation at Heathrow Airport today and are supporting as required. Flights from London Gatwick are operating as normal today," Gatwick said on X.

Airport authorities said they "expect significant disruption" over the coming days.

Around 150 people were evacuated from nearby properties because of the fire.

London Fire Brigade assistant commissioner Pat Goulbourne said firefighters had worked "tirelessly in challenging conditions" to bring the blaze under control.

The outage left 100,000 homes without power overnight, Energy Secretary Miliband said. By morning, power had been restored to all but around 4,000.

As the full scale of the disruption began to emerge, the minister faced questions about how one fire could shut down an entire airport.

He said electricity distribution network National Grid had told him they had not seen "anything like the scale" of what happened.

"But it makes Heathrow look quite vulnerable and therefore we've got to learn lessons, as I say, about not just Heathrow but how we protect our major infrastructure," he told ITV.

The chair of the parliamentary transport committee, Ruth Cadbury, said it was "speculative" to suggest at the moment that arson might have caused the fire.

But she told Times Radio: "There are obviously questions about it."

- Disruption -

Flights from all over the world were affected by the closure and aviation consultant Philip Butterworth-Hayes told AFP would cost "certainly more than £50 million ($64.7 million)" to the airport and airlines.

In January, the UK government gave permission for Heathrow to build a third runway -- which could be ready by 2035 -- after years of legal disputes due to opposition from local residents.

Five major airports serve the British capital and towns nearby.

But capacity is stretched, especially at Heathrow, whose two runways each measure almost four kilometres (2.5 miles) in length.

The airport itself covers a total area of 12.3 square kilometres (4.8 square miles).

Situated 25 kilometres west of central London, Heathrow's main flight destinations last year were Dublin, Los Angeles, Madrid and New York.

C.Diez--HdM