One week after a catastrophic fire at the North Hyde electrical substation plunged the UK’s flagship Heathrow Airport into chaos, questions are mounting about what went wrong—and what the incident reveals about the vulnerabilities in Britain’s aging power infrastructure.

A massive explosion and fire that erupted around 8:20 p.m., on Thursday, March 20, at the North Hyde electrical substation near the international airport caused widespread power outages across West London and prompted the temporary closure of Heathrow Terminals 2 and 4. The airport faced significant disruptions, forced to cancel over 1,300 flights—outages that affected more than 290,000 passengers.

At its peak, the fire knocked out power to an estimated 67,000 households and businesses. The London Metropolitan Police declared a major incident at 12:42 a.m. on March 21. With more than 70 London Fire Brigade personnel on the scene, crews worked to evacuate residents and contain the blaze.

“The fire involved a transformer comprising 25,000 liters of cooling oil fully alight,” said London Fire Brigade Deputy Commissioner Jonathan Smith during a press briefing. “This created a major hazard due to the still live high-voltage equipment and the nature of the oil-fueled fire.” Firefighters worked in what Smith described as “very hazardous conditions,” establishing a 200-meter exclusion zone while coordinating with “specialist power network engineers” from National Grid, which owns the substation, to work toward restoring power.

Power supplies were ultimately restored to all customers connected to the North Hyde substation at 6 a.m. on March 22, National Grid reported, following a grid reconfiguration in partnership with local grid operator SSEN Distribution as an interim solution.

Read more of the post Heathrow Airport Transformer Fire Prompts Urgent Inquiry, Exposes Cracks in Grid Resilience at POWER Magazine.

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