Heathrow Airport will resume normal operations today, Saturday, March 22, 2025, following a massive power blackout caused by the outbreak of a fire at an adjacent power substation. The 18-hour closure of the busiest airport in Europe was necessitated by the power failure, which started late on Thursday night, grounding around 200,000 passengers and affecting more than 1,350 flights.

The fire took place in the North Hyde electrical substation in West London's Hayes district around 11 p.m. on Thursday and resulted in an enormous outage of power at both the airport and the neighboring areas. More than 70 firefighters were rushed to the spot to fight the inferno, which engulfed about 25,000 liters of oil. The London Fire Brigade described the situation as "challenging and hazardous."

The airport, in turn, suspended all operations on Friday, instructing passengers to avoid the airport and rerouting incoming flights to airports elsewhere in the UK and Europe. The airport had originally intended to process 1,351 flights with up to 291,000 passengers that day.

Partial operations were resumed late on Friday night, with the first plane to arrive being a British Airways flight after power was restored. Overnight flight bans were temporarily suspended by the British government to assist in clearing the backlog, although disruption will continue for a number of days while airlines reposition planes and reschedule passengers.

Heathrow's Chief Executive, Thomas Woldbye, apologized for the disruption and promised that the airport hopes to resume "100% operation" on Saturday. He highlighted the magnitude of the incident, stating that the loss of power was comparable to that of a mid-sized city, and that although backup systems performed as they were supposed to, they are not capable of powering the whole airport
Investigations into the cause of the blaze are still being carried out.

The Metropolitan Police, under the direction of the Counter Terrorism Command, made a preliminary assessment and reported that they are not currently treating the matter as suspicious, though investigations continue. The London Fire Brigade's investigation will look at the electrical distribution equipment.

The event has prompted questions regarding the vulnerability of critical infrastructure. Experts have wondered how one substation fire would result in such extensive disruption and how critical services need to be better protected through improved contingency planning.

Customers are encouraged to verify with their airlines prior to flying to the airport since flight schedules may take a few days to return to normal. Airlines are doing everything possible to rebook stranded passengers and reposition planes to reduce further disruptions.