The United Kingdom’s Heathrow Airport, one of the world’s busiest air travel hubs, was forced to shut down on Friday following a massive power outage caused by a fire at an electrical substation, leading to widespread flight cancellations and disruptions.

The airport authorities announced that Heathrow would remain closed until 23:59 GMT on March 21 as a safety measure for passengers and staff.

“To maintain the safety of our passengers and colleagues, Heathrow will be closed until 23h59 on 21 March,” the airport said in a statement on X, formerly Twitter.

“Passengers are advised not to travel to the airport and should contact their airline for further information. We apologise for the inconvenience.”

The shutdown has thrown travel schedules into chaos, with at least 1,351 flights affected, according to flight tracking service FlightRadar24. Additionally, about 120 aircraft that were en route to Heathrow at the time of the closure were either diverted to alternative airports or forced to return to their points of origin.

London's Heathrow Airport announces complete shutdown due to 'significant power outage' | CNN

The London Fire Brigade confirmed that ten fire engines and approximately 70 firefighters had been dispatched to tackle the fire near the airport. Officials urged residents to avoid the area and keep their windows shut to prevent smoke inhalation.

“We are on scene working to bring the fire under control,” the fire service posted on X. “This will be a prolonged incident, with crews remaining on scene throughout the night.”

Heathrow, which handled nearly 84 million passengers in 2024, ranks among the busiest airports globally. The unexpected closure has left thousands of passengers stranded, with airlines scrambling to accommodate affected travellers.

While authorities have yet to confirm the full extent of the damage, the power failure underscores the vulnerability of critical infrastructure to such incidents.

Further updates on flight rescheduling and the reopening of the airport are expected as emergency services continue their operations.

Notable incidents of airport closures in UK

Heathrow Airport Drone Disruption (December 2018 - January 2019)

Cause: Reports of drone activity near the runway led to major disruptions at Heathrow and Gatwick airports.

Impact: Gatwick Airport was shut down for 36 hours, affecting over 1,000 flights and stranding 140,000 passengers. Heathrow also temporarily halted operations as a precaution.

Icelandic Volcanic Ash Cloud (April 2010)

Cause: The eruption of Iceland’s Eyjafjallajökull volcano released a massive ash cloud, which posed risks to aircraft engines.

Impact: UK airspace, including all major airports like Heathrow, Gatwick, and Manchester, was closed for nearly a week, disrupting over 100,000 flights across Europe.

Heathrow Security Scare (August 2006)

Cause: A foiled terrorist plot to detonate liquid explosives on transatlantic flights led to heightened security measures.

Impact: Heathrow and other UK airports were partially shut down, leading to mass cancellations and delays. Passengers faced stringent security checks, including a temporary ban on carrying liquids in hand luggage.

Heathrow Runway Blockade by Climate Activists (July 2015)

Cause: Activists from the group "Plane Stupid" broke into Heathrow’s north runway to protest airport expansion.

Impact: Several flights were delayed or cancelled, and police arrested multiple protesters.

Snowstorm and Freezing Conditions (December 2010 & March 2018)

Cause: Heavy snowfall and icy conditions led to airport closures at Heathrow, Gatwick, and Manchester.

Impact: In December 2010, Heathrow was shut for several days, leading to major flight disruptions. Similarly, the "Beast from the East" snowstorm in March 2018 caused mass cancellations and delays.

Heathrow Fuel Supply Disruption (May 2017)

Cause: A fuel supply system failure affected aircraft refuelling.

Impact: Dozens of flights were cancelled, and passengers faced significant delays.