London's Heathrow Airport plans to slowly resume some flights later Friday and hopes to return to a full schedule on Saturday.
The airport said in a statement that the first flights will be to bring stranded passengers back from other airports in Europe and to get airplanes back in the right place.
Heathrow was closed Friday after a fire at a nearby electrical substation cut power to Europe's busiest airport, forcing it to shut and disrupting global travel for hundreds of thousands of passengers.
British Airways chief executive Sean Doyle says the closure of Heathrow Airport will have a "huge impact" on passengers even after it reopens.
Heathrow is BA's base and it is the airline most affected by the shutdown. Doyle said the airline had been due to operate more than 670 flights carrying more than 100,000 passengers on Friday.
Passengers booked to fly to or from Heathrow on Saturday or Sunday are being given the option to rebook to a later date for free.
In a video to customers, Doyle said: "We hope that power will be restored as soon as possible. But even when that does happen, 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."
Travelers say power is back on at one of the two Heathrow Airport terminals left in the dark after a fire at an electricity substation.
Lights came back on at Terminal 4 on Friday afternoon. Firefighters earlier said that terminals 2 and 4 at the airport had lost all power after the blaze. Heathrow shut the airport to all arriving and departing flights until at least midnight.
Electricity distributor National Grid said it had found an "interim solution" that reconfigured its network, allowing electricity to be restored to all customers, including Heathrow.
It's unclear whether power to the airport has been fully restored.
Heathrow is facing questions about how it could be shut down by a fire at a single substation 2 miles (3.2 kilometers) away.
The airport said it has emergency backup systems that worked as expected, but they are not enough to run the whole airport.
Willie Walsh, director general of airline industry group IATA, took to social media to lambaste Heathrow's management.
"Firstly, how is it that critical infrastructure - of national and global importance - is totally dependent on a single power source without an alternative," he said in a post from IATA's account on social media platform X. "If that is the case - as it seems - then it is a clear planning failure by the airport."
He also questioned whether it was fair that airlines are solely responsible for "picking up the tab when infrastructure fails."
