Heathrow Airport, Europe's busiest, was forced to shut down on Friday due to a significant fire at an electrical substation that provides power to the expansive facility. The incident, which occurred in Hayes, a town in the London borough of Hillingdon, caused a widespread power outage, impacting not only the airport but also thousands of homes and local businesses in the surrounding area.

Airport authorities have warned of "significant disruption" expected to last for several days, potentially affecting hundreds of flights and thousands of passengers. Heathrow initially announced it would be closed until just before midnight on Friday (2359 GMT). Passengers were strongly advised not to travel to the airport until it reopened, and to contact their airline for further information.

The London Fire Brigade (LFB) reported that the fire at the substation was "significant," with images circulating on social media showing large flames and smoke billowing from the site. These images, though not immediately verified by AFP, depicted a serious situation. Videos purportedly taken inside Heathrow's terminals showed darkened shops and deserted corridors illuminated only by emergency lighting, underscoring the severity of the power outage.

Assistant Commissioner Pat Goulbourne of the London Fire Brigade stated that the fire was first reported at 11:23 pm (2323 GMT). He emphasized the challenging conditions faced by firefighters working to control the blaze and minimize disruption. The LFB received nearly 200 calls regarding the fire, highlighting the widespread concern and impact of the incident.

Scottish and Southern Electricity Networks, the utility firm responsible for the area, reported an "unplanned outage" that left over 16,000 homes without power. The company acknowledged the widespread power cut affecting customers around Hayes, Hounslow, and surrounding areas, and indicated they were working to restore power as quickly as possible.

The closure of Heathrow, which handles over 80 million passengers annually and approximately 1,300 takeoffs and landings daily, led to numerous flight diversions. FlightRadar24 reported that a Qantas flight from Perth, Australia, was diverted to Paris, while a United Airlines flight from New York was rerouted to Shannon, Ireland. These diversions illustrate the immediate impact on international air travel.

The incident raises concerns about the resilience of critical infrastructure supporting major transportation hubs. Heathrow's two runways, each almost four kilometers in length, serve 200 destinations in more than 80 countries via four terminals. The airport, originally opened in 1946 as London Airport and later renamed after the hamlet of Heath Row, plays a vital role in global connectivity.

The cause of the fire remains under investigation. Authorities have cordoned off a 200-meter area around the substation as a precaution, and local residents have been advised to keep doors and windows closed due to the significant amount of smoke. The LFB warned that disruption was expected to increase and urged people to avoid the area.

In January, the government approved the construction of a third runway at Heathrow, potentially ready by 2035, following years of legal battles due to objections from local residents. This expansion plan underscores the ongoing need to address capacity constraints at Heathrow and the broader London airport system, which includes five major airports serving the capital and nearby towns.

The fire at the electrical substation serves as a stark reminder of the potential for unforeseen events to disrupt critical infrastructure and highlights the importance of robust emergency response plans and infrastructure maintenance to mitigate the impact of such incidents.