London’s Heathrow Airport, the UK’s largest and one of the world’s busiest international hubs, has shut down operations until midnight on Friday, March 21, 2025, following a major power outage triggered by a fire at a nearby electrical substation in Hayes.
The closure has led to the cancellation of over 1,300 flights, disrupting global travel and leaving thousands of passengers stranded. Heathrow has warned of “significant disruption” for days, urging travelers to avoid the airport entirely until it reopens.
The blaze, which erupted late Thursday at the North Hyde substation owned by National Grid, continued burning into Friday morning, with part of a transformer still alight as reported by the London Fire Brigade (LFB) just before 6 a.m.
The LFB has deployed firefighters to combat the fire in challenging conditions, establishing a 200-meter cordon and evacuating approximately 150 people from the area. Assistant Commissioner Pat Goulbourne described the incident as “highly visible and significant,” noting it will be a prolonged effort, with crews expected to remain on-site throughout the night and into the morning. The cause of the fire remains under investigation.
Heathrow, which recorded a record 6.3 million passengers in January and handles about 1,300 daily take-offs and landings, confirmed the outage has affected its operations. “We do not have clarity on when power may be reliably restored,” the airport stated, advising passengers not to travel to the facility “under any circumstances.”
FlightRadar24 data shows 679 arrivals and 678 departures were scheduled for Friday, all now canceled. Additionally, nearly 100 flights have already been scrapped, with around 120 inbound aircraft diverted to alternative airports such as Gatwick, Stansted, Birmingham, Paris Charles de Gaulle, Helsinki, and Shannon in Ireland. Eurocontrol reported arrivals at Heathrow are “regulated at zero” due to the power failure.
The effects are intensifying congestion at nearby airports. At Gatwick, a British Airways flight from Singapore diverted from Heathrow, waited over 90 minutes on the tarmac as planes queued for gates, eventually opting to bus passengers to the terminal.
British Airways, the UK’s flag carrier, told customers to avoid Heathrow until further notice, citing a “significant impact” on operations.
Air India also canceled all its remaining flights to and from Heathrow on Friday, with one Mumbai-bound plane turning back mid-flight and another from Delhi rerouting to Frankfurt. Flights to Gatwick, however, remain unaffected, the airline noted.
National Grid, a FTSE 100 company, said the fire damaged equipment at the substation, cutting power to over 16,000 homes in west London alongside the airport. “We are working at speed to restore power supplies as quickly as possible,” it stated, promising updates soon. The LFB has warned of increasing disruption as the day progresses, urging the public to steer clear of the Hayes area.
This crisis follows the Labour government’s recent backing of Heathrow’s expansion, including a third runway, championed by Chancellor Rachel Reeves in January to boost economic growth. Heathrow, operational since 1930 and Britain’s only hub airport, saw passenger numbers rebound to pre-pandemic levels last year.
Now, with the world’s second-busiest international airport behind Dubai, per OAG data out of service, the closure underscores its critical role in global aviation. Passengers are advised to contact their airlines for updates as authorities race to resolve the ongoing emergency.
