"There was no lack of capacity from the substations," he said. "Each substation individually can provide enough power to Heathrow. "Airport officials said the closure was due to the time it took to switch to the other substations and make safety checks. "Hundreds of critical systems across the airport were required to be safely powered down and then safely and systematically rebooted," a Heathrow Airport spokesperson said. "Given Heathrow's size and operational complexity, safely restarting operations after a disruption of this magnitude was a significant challenge.

Source: The Times March 24, 2025 09:17 UTC