What we know about the closure and reopening of Heathrow Airport
Around 200,000 passengers were affected by Friday’s closure of Europe’s busiest airport.
A power outage forced Heathrow to close for much of Friday, resulting in major disruption for passengers flying to and from Europe’s busiest airport.
The power loss was caused by a blaze at an electricity substation in Hayes, west London, late on Thursday.
Here, the PA news agency details what we know about the incident and how it affected the transport hub.
– What caught fire?
Heathrow and thousands of homes were left without power after a transformer within the substation caught fire.
London Fire Brigade deputy commissioner Jonathan Smith said: “The fire involved a transformer comprising 25,000 litres of its cooling oil fully alight.
“This created a major hazard owing to the still live high voltage equipment and the nature of an oil-fuelled fire.”
– What caused the fire?
It is not currently known what caused the blaze.
The Metropolitan Police said they are not treating the incident as suspicious, although the force added that inquiries are ongoing.
Following that confirmation from the Met, the London Fire Brigade announced its investigation will focus on the electrical distribution equipment.
– How did the fire lead to Heathrow’s power outage?
Heathrow chief executive Thomas Woldbye said the airport has three substations, each with a back-up transformer.
The fire broke out at one of the three substations where the back-up transformer also failed, causing a loss of power to Heathrow.
– Why did the airport have to close?
Mr Woldbye said the airport can run on power from the two unaffected substations but had to “restructure the supply”.
“So, we’re not out of power but we have to restructure our power supply,” he said.
“To do that we have to close down systems – that is safety procedure, we will not go around that.”
– What disruption was caused?
Heathrow is Europe’s busiest airport, with more than 83.9 million passengers travelling through its terminals in 2024 and around 200,000 passengers were affected by Friday’s closure.
It is believed to be the worst disruption at Heathrow since December 2010, when thousands of Christmas getaway passengers camped in the terminals because of widespread cancellations caused by snow.
– What investigations have been launched?
Energy Secretary Ed Miliband has ordered the National Energy System Operator (NESO) to “urgently investigate” the power outage and is working with Ofgem and using powers under the Energy Act to formally launch the grid operator’s investigation.
NESO officials are expected to report to the Department for Energy Security and Net Zero and Ofgem with initial findings within six weeks.
Akshay Kaul, director general for infrastructure at Ofgem, said it would “not hesitate to take action” if the review found any breaches of standards or licence obligations.
Meanwhile, an internal review of the airport’s crisis management plans and its response to Friday’s power outage will be undertaken by former transport secretary Ruth Kelly, who is an independent member of Heathrow’s board, Heathrow chairman Lord Paul Deighton said.
– How did the airport’s reopening go?
Flights were not able to resume until Friday evening, with restrictions on overnight flights temporarily lifted after hours of closure.
The airport said it served more than 250,000 passengers on Saturday, with “punctual flights and almost all passengers waiting less than five minutes for security”.
A Heathrow spokesperson said the airport is expecting to operate a “full schedule of over 1,300 flights” on Sunday.
British Airways said it was also expecting to run a “near-full schedule” on Sunday and passengers should go to the west London airport as normal unless told otherwise.
The airline said it operated about 90% of its scheduled flights on Saturday when Heathrow said it was “open and fully operational”.
