Heathrow says it's resuming some flights, after a day of chaos for hundreds of thousands of travelers due to a power outage

• Heathrow Airport said Friday afternoon it was resuming flights after being closed most of Friday.
• A fire caused a power outage, closing Europe's busiest airport and causing travel chaos.
• The airport said it hoped to resume full operation on Saturday.

London's Heathrow Airport has said it is resuming some flights after being closed most of Friday after a power outage.

The airport closed early Friday morning due to "a significant power outage" caused by a fire in a nearby electrical substation.

An airport spokesperson later warned people to expect "significant disruption over the coming days."

In a post on X at 4.13 p.m. local time, Heathrow said it was now "safely able to restart flights" and would prioritize the "repatriation and relocation of aircraft."

The airport said it hoped it would return to full operation on Saturday, but asked passengers not to travel to the airport unless their airline advised them to do so.

The airport usually welcomes around 200,000 passengers and 1,300 flights a day but was cordoned off and almost completely empty most of the day. Planes were diverted, with some British Airways flights rerouting to London Gatwick, while other airlines diverted to more distant locations.

The aviation analytics firm Cirium told BI that there were due to be 665 departures and 669 arrivals at the airport on Friday, equating to more than airline 290,000 seats.

At around 2 p.m. local time, the UK National Grid, which is responsible for the country's electricity network, said that the power supply had "been reconfigured to restore all customers impacted," including the airport. But it warned that this was an "interim solution."

On Friday morning, barricades and signs were placed around the airport to prevent drivers from entering its perimeter.

Terminal Five is the busiest terminal, but on Friday morning, a BI reporter found that the area around it was eerily quiet. Dozens of people were waiting outside, mostly checking their phones for travel updates.

Rhythem Chauhan was one of them. She had been there since 5 a.m., awaiting news of her flight home to Delhi.

"It's heartbreaking," she told BI, saying she hadn't been back to India in five years.

Luke Metcalf told BI he was supposed to fly to Thailand this morning but his flight was diverted to another London airport, Gatwick, and would take off at 5 p.m. instead.

"It is what is, I'm a bit disappointed but there's not much you can do about it," he said.

Another stranded passenger, Andrew Palmer, was supposed to fly to San Francisco but decided to stay at a hotel near the airport after seeing the news on TV.

"I'm disappointed, very disappointed," he told BI. "The disheartening thing was that I had an internal flight to Las Vegas as well."

Heathrow was the fourth busiest airport in the world and the busiest in Europe in 2024, according to OAG, a travel data company, behind only Tokyo Haneda Airport, Dubai International Airport, and Hartsfield-Jackson Atlanta International Airport.

Last year, about 83.9 million people flew through Heathrow, up 6% from the previous year.

The airport's closure led to multiple flight diversions, with some British Airways flights rerouting to London Gatwick, while other airlines diverted to more distant locations, according to Cirium.

In a later statement, the BA spokesperson said the power outage led to the cancellation of all short-term flights on Friday.

"Our teams are currently working hard to review our long-haul schedule as well as the implications for our schedule for tomorrow and beyond," they added.

The airline said it was redirecting flights already on their way to Heathrow to other UK airports.

A spokesperson for Virgin Atlantic, whose main UK hub is Heathrow, told BI that the closure was having a "significant impact" on its flight operations to and from the airport. They also advised customers not to travel to Heathrow.

"We're incredibly sorry for the disruption this will cause and are working with our teams to ensure customers can complete their journeys as quickly as possible," the spokesperson said.

Qatar Airways, in an X post, said that the closure had affected five flights from London to Doha and four flights from Doha to London.

The fire occurred at an electricity substation in Hayes in West London, about 1.5 miles from the airport. The cause of the fire is not yet known.

London's Metropolitan Police said its counter-terrorism command would lead the fire investigation, given "the impact this incident has had on critical national infrastructure."

"This is due to the specialist resources and capabilities within that command that can assist in progressing this investigation at pace to minimise disruption and identify the cause," the force added in a statement.

The London Fire Brigade said in a post on X that 10 fire engines and about 70 firefighters were called to the scene. Images showed large flames and plumes of thick black smoke.

"This will be a prolonged incident, with crews remaining on scene throughout the night," it said on its website.

In a press briefing late Friday morning, the fire brigade said the fire was not fully extinguished but was under control, and that 5,000 homes were still without power.

Sadiq Khan, the mayor of London, said in a statement that electricity suppliers were working hard to restore power.

London has several other international airports including Gatwick, the city's second-busiest airport, and Stansted, known for budget flights and flights to Europe.