London Heathrow Closed by Fire in Biggest Disruption in Decades

(Bloomberg) -- London’s Heathrow airport suffered its worst disruption in at least two decades, after a nearby fire cut power to the hub and brought travel to a standstill for hundreds of thousands of passengers.

The airport — the busiest in Europe and fourth most active in the world — will be closed all day Friday and service interruptions are likely to continue for days, authorities said, as workers try to connect backup electrical supplies. 

“Passengers should not travel to the airport under any circumstances,” Heathrow said in a statement. The airport said it can’t say when power will be reliably restored.

The closure will force more than 1,300 flights to be canceled or rerouted on Friday alone. Heathrow, home to British Airways, is a major hub for transatlantic travel, as well as connections to the Middle East and Asia. While some nearby airports such as London Gatwick have accepted diverted flights, others are being sent as far as Frankfurt. 

BA, the flagship carrier of IAG SA, said in a statement that the outage will “clearly have a significant impact on our operation and our customers and we’re working as quickly as possible to update them on their travel options for the next 24 hours and beyond.”

An outage on the current scale is unprecedented for the airfield. About 677 flights will be affected at British Airways alone, according to ch-Aviation, a data-collecting service for the industry. That’s followed by 62 flights for Virgin Atlantic Airways Ltd. and 42 flights for Deutsche Lufthansa AG, according to the data.

IAG shares fell as much as 4.1%, bringing their year-to-date decline to 6.8%. The shares almost doubled last year as the company improved services and paid down debt.

The outage is likely to raise questions about the robustness of Heathrow’s infrastructure, and why an airport of such scale and importance had no redundancy systems to keep operations going.

Heathrow is currently making a pitch to add a third runway, a longrunning ambition to expand traffic and remain competitive with global hubs like Dubai or Istanbul.

The blaze erupted at an electrical substation in Hayes, north of Heathrow, just before midnight, causing a local power outage. The airport closed at around 1:30 a.m. on Friday and will remain shuttered all day, it said. 

The fire also cut power to thousands of nearby residents. Its cause wasn’t clear, the fire service said.

Previous Closures

Heathrow, which is also home to Virgin Atlantic, handles some 1,400 flights and 200,000 passengers every day, and about 40 aircraft take off every hour at peak times on average.

Ryanair Holdings Plc, the Irish budget carrier, said it would add four flights on Friday and four on Saturday between its London Stansted hub and Dublin to accommodate stranded travelers.

The last major crisis for Heathrow occurred in August 2023 when the UK’s airspace shut down because of a technical issue with the air traffic control system. The outage was fixed after a few hours but led to many flight delays and cancellations at Heathrow and other airports, creating chaos for passengers.

Hundreds of flights were canceled at Heathrow on July 10, 2006, after authorities in London uncovered a plot to detonate liquid explosives on transatlantic flights. Still, the airport remained open and flying resumed that evening.

On Friday, about 120 planes already en-route when the airport closed were diverting or sent back to their origin, including flights operated by Qantas Airways Ltd., Delta Air Lines Inc. and American Airlines, according to tracking service Flightradar24.

Carriers including Emirates, the world’s largest international airline with more than a dozen daily flights into Heathrow, said they’ve canceled some connections. “We’re monitoring the situation closely and will update our customers as the situation develops,” Emirates said. 

Virgin said that all incoming and outbound traffic has been canceled until midday, and that the schedule for the afternoon is under review. Some airlines began rerouting incoming traffic to other airports, including Abu Dhabi carrier Etihad Airways, which diverted a Heathrow-bound plane to Frankfurt. 

Gatwick Airport said its service is operating normally, and that it’s taken seven flights so far that were diverted from Heathrow. 

Even if service resumes after Friday, there’ll be a significant ripple-on effect that may be felt for days, with aircraft and crew out of position. Airports sometimes experience disruptions because of weather or personnel strikes, though a full-day complete shutdown is extremely rare. 

In early 2023, Frankfurt airport — among the busiest in Europe — suffered serious disruptions following damage to broadband cables at a rail location in the northern part of the German city. UK airports have experienced outages in past years because of air-traffic control systems, though these were often just a matter of hours. 

Footage on social media showed a huge blaze at the substation located less than two miles from the airport. Some local residents have been evacuated as a precaution, according to authorities. 

“This will be a prolonged incident, with crews remaining on scene throughout the night. As we head into the morning, disruption is expected to increase,” the London Fire Brigade’s Assistant Commissioner Pat Goulbourne said in a statement.

(Updates with flight diversions, previous disruptions)

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