A fire knocked out power to London's Heathrow Airport on Friday, shutting down the facility and affecting hundreds of thousands of passengers before authorities announced a partial resumption of flights.
At least 1,350 flights to and from Heathrow were affected by the shutdown, including several from US cities that were canceled, flight tracking service FlightRadar 24 said.
Later on Friday, the airport said it would begin flights for stranded passengers, and hoped to resume operation on Saturday.
The British Airways jet touched down on Friday about 18 hours after the airport was closed due to a massive power outage.
Heathrow had canceled all flights for the day but was able to resume some after electricity was restored.
Heathrow's boss has apologised for the disruption caused by the airport's daylong closure, but says there was no choice but to shut the airport for safety reasons.
Chief Executive Thomas Woldbye said "we would not shut down the airport unless we had severe safety concerns."
Woldbye said Heathrow drew power from three substations and two are still working. He said that is enough to restore power, but it was necessary to restructure the electricity supply after the fire to get Heathrow back up and running.
Woldbye rejected suggestions that Heathrow did not have adequate contingency plans, saying the incident was "unprecedented" and "all our procedures have been working as they should."
He said "contingencies of certain sizes we cannot guard ourselves against 100% and this is one of them."
Emirates Airline and Etihad Airways had earlier cancelled flights to Heathrow and announced diversions in their flight schedule due to the Heathrow closure, according to reports.
Emirates said, “Following the reopening of London Heathrow Airport ‑ Emirates will resume flight operations starting with flight EK07 (DXB‑LHR) on 22 March.
“Customers connecting onwards to London Heathrow Airport with confirmed bookings will be accepted to travel from the point of origin.
“For cancelled bookings, customers can contact their booking agent for rebooking options. Customers who have booked directly with Emirates can contact us for assistance.”
According to Indo-Asian News Service, India's largest carrier Air India on Friday said that its operations, to and from London Heathrow (LHR), have been disrupted following the temporary suspension of operations at the airport.
European shares fell alongside other major global stock markets on Friday on uncertainty over trade tensions and geopolitical conflicts, while travel and leisure stocks were hit after a fire led to the closure of Britain's Heathrow Airport.
The pan-European STOXX 600 was down 0.6% in a third consecutive session of declines.
British Airways said it had received clearance to depart eight long-haul flights from 7:00 pm to cities including Johannesburg, Singapore and Riyadh.
Around 230,000 passengers use Heathrow every day — 83 million a year — making it one of the world's busiest airports.
London's Metropolitan Police said the force's Counter Terrorism Command was leading the investigation into the fire given the "impact this incident has had on critical national infrastructure".
Firefighters were called to the "highly visible" blaze at the substation shortly after 2320 GMT on Thursday and around 70 were sent to battle the fire, which was brought under control by 0800 GMT Friday.
The outage left 100,000 homes without power overnight. Electricity distribution network National Grid said that at around 1400 GMT power had been partially restored to Heathrow as well as to local residents affected.
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".
The airport shutdown left many frustrated passengers struggling to make alternative arrangements.
Around 120 Heathrow-bound planes were in the air when the closure was announced, according to Flightradar24.
The UK's second-busiest airport, Gatwick, accepted some flights from Heathrow, while others were diverted to European airports including Shannon in southwestern Ireland, Frankfurt in Germany and Paris Charles de Gaulle.
London Fire Brigade deputy commissioner Jonathan Smith said firefighters had worked "tirelessly in challenging and very hazardous conditions".
He told reporters the fire had involved a "transformer comprising of 25,000 litres of cooling oil fully alight" posing a hazard due to the substation's "still live high voltage equipment".
Agencies