(Bloomberg) -- London’s Heathrow airport said it’s slowly coming back from an unprecedented daylong blackout that brought travel to a standstill for hundreds of thousands of passengers at Europe’s busiest airport.
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The airport will begin some flights later on Friday that are focused on repatriating displaced passengers and relocating aircraft, it said in a statement. For Saturday, Heathrow said it hopes to run a ful operation. Still the airport advised passengers not to show up unless they’d been told to do so by their airlines.
The update followed a day of mass chaos for travelers who had aimed to leave or arrive via the most important hub in Europe. The UK Metropolitan Police said earlier that its counter-terrorism command is leading a probe into the fire at a nearby power substation that led to the outage, though there’s no indication at this point of foul play.
“This incident will have a substantial impact on our airline and customers for many days to come, with disruption to journeys expected over the coming days,” said Sean Doyle, the head of British Airways, which is the biggest single operator at the airport.
By mid afternoon, the company in charge of the affected electricity grid said it had restored the ability to resupply the parts of Heathrow connected to the damaged substation, pointing to progress in fixing the outage.
The closure forced 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 nearby airports such as London Gatwick have accepted some diverted flights, others are being sent as far as Frankfurt.
The financial fallout from the day-long disruption may reach reach between $80 million and $100 million, factoring in costs related to accommodation, food, and transportation, as well as broader operational impacts that include rerouting, schedule disruptions and aircraft repositioning, said Ronan Murphy, director at Alton Aviation Consultancy
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, which compiles industry data. That’s followed by 62 flights for Virgin Atlantic Airways Ltd. and 42 flights for Deutsche Lufthansa AG.
IAG SA, the parent of British Airways, fell as much as 4.3% in London, bringing the decline this year to 5.8%. The shares almost doubled in 2024 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 lacked the redundancy systems needed to keep operations going. At the same time, an operation the size of Heathrow has considerable energy requirements, complicating the availability of a reserve source to meet its needs.
Energy Secretary Ed Miliband told LBC radio on Friday that the “catastrophic” fire had taken out a backup generator for Heathrow, as well as the electricity substation that serves it. He added that for now, “there’s no suggestion that there is foul play.”
Prime Minister Keir Starmer said in a statement that he’s “receiving regular updates and I’m in close contact with partners on the ground.” The police said that “while there is currently no indication of foul play we retain an open mind at this time.”
Assessments were under way to determine whether circumstances were suspicious, according to an official with knowledge of the matter. Police involvement will be peripheral unless there’s reason to mount an investigation, the person said.
Heathrow is currently making a pitch to add a third runway, a long-running ambition to expand traffic and remain competitive with global hubs like Dubai or Istanbul. Its recently realigned ownership now includes French private-equity firm Ardian SAS, Qatar Investment Authority and Saudi Arabia’s Public Investment Fund as its top investors.
The blaze was under control as of midmorning on Friday, officials said. It erupted at an electrical substation in Hayes, north of Heathrow, just before midnight, causing a local power outage that cut service to thousands of nearby residents and local businesses, and caused some evacuations.
The airport closed at around 1:30 a.m. on Friday and will remain shuttered all day. The station that caught fire is owned by National Grid Plc, which said it’s working “at speed’ to restore power supplies as quickly as possible.
Sue Thomas, who flew in to Heathrow Thursday evening from Canada to visit family in Penzance in Cornwall, said power went out at her Premier Inn hotel room near the airport at 10:30 p.m.
“Everything went black,” she said in an interview at Paddington Station on Friday where she waited for a train. “The power went out, the water wasn’t running, no one was allowed in or out.”
Staff at the hotel couldn’t even allocate rooms because everything is automated, the lifts weren’t working and the hotel corridors were in total darkness, she 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. EasyJet Plc said it’s also putting larger aircraft on key routes to provide more seats.
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 9:30 p.m., and that the rest of the schedule 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 once service resumes, 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.
This time, passengers are facing significant disruptions. Nick Stone, an investor from Los Angeles, was boarding a Eurostar train to Paris at St. Pancras Station in London on Friday morning. His canceled flight will cause him to miss his daughter’s 12th birthday, he said.
Eurostar said it’s adding extra capacity, including one additional service from London to Paris and one from Paris to London to provide alternative travel options for stranded passengers.
Sabrina and Raik Becker, a German couple on holiday in London, were scheduled to head back to Hanover on a 1.5 hour flight from Heathrow on Friday. Instead, they’re now taking the Eurostar to Brussels and then onward to Cologne before getting to their destination, a journey that will take more than 12 hours and cost an extra €1,000 ($1,083).
They said they don’t know if they’ll get their money back.
--With assistance from Ailbhe Rea, Lucy White, Leen Al-Rashdan, Hema Parmar and Rachel Lavin.
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