560,000 passengers affected: What led to Heathrow’s worst shutdown in years?

London‘s Heathrow Airport, one of the busiest international travel hubs, has resumed flights after a major power outage forced it to halt operations for nearly a full day. The outage was triggered by a fire at the North Hyde electrical substation, cutting off power to key airport systems and affecting surrounding areas. While flights are now restarting, Heathrow has warned of continued disruptions and has urged passengers not to travel to the airport unless advised by their airline. The airport expects to return to full operation by Saturday, but delays and cancellations may persist for days as airlines work to recover.

The incident has raised concerns over Heathrow’s infrastructure resilience, especially given its history of operational failures caused by power outages, system failures, and extreme weather conditions.

How Many Flights and Passengers Were Affected?

The disruption has had a significant impact on global air travel, affecting hundreds of thousands of passengers. According to aviation analytics firm Cirium, an estimated 290,000 passengers were impacted by the closure on Friday, with 669 scheduled departures from Heathrow affected. An additional 270,000 passengers faced delays on Saturday as airlines struggled to recover operations.

British Airways, which operates a large portion of flights at Heathrow, has confirmed that it expects to run around 85% of its scheduled services on Saturday. However, the airline has warned that the recovery process is highly complex, as aircraft, crew, and passengers remain out of place following the disruption.

The Scale of the Fire and Emergency Response

The fire at the North Hyde electrical substation broke out late Thursday night, with plumes of thick smoke visible across West London. According to the London Fire Brigade, the fire involved a transformer containing 25,000 litres of cooling oil, which made it more difficult to control. Firefighters worked through the night, battling hazardous conditions created by the still-live high-voltage equipment.

At its peak, the emergency response involved 70 firefighters and 10 fire engines tackling the blaze. A 200-meter safety cordon was established, leading to the evacuation of 150 residents. Widespread blackouts affected homes and businesses in the Heathrow area, adding to the disruption. By Friday night, authorities reported that about 5% of the fire remained active in isolated hotspots. The cause remains under investigation. While initial assessments indicate no foul play, the Metropolitan Police‘s Counter Terrorism Command is leading the inquiry due to the impact on critical national infrastructure.

Has Heathrow Faced Similar Disruptions Before?

Heathrow has experienced multiple high-profile operational failures over the years, often linked to power outages, technical malfunctions, and severe weather. In 2017, a British Airways IT system failure, partly attributed to a power surge, stranded 75,000 passengers, leading to mass cancellations. In 2019, a British Airways strike caused hundreds of flight disruptions, highlighting how the airport’s tightly managed schedule is vulnerable to external factors. In 2022, Storm Eunice led to major flight cancellations, further demonstrating Heathrow’s susceptibility to infrastructure-related issues.

Globally, airport power outages have caused significant disruptions before. In 2017, Atlanta’s Hartsfield-Jackson International Airport, the world’s busiest at the time, suffered an 11-hour blackout due to a fire in an underground electrical facility, grounding over 1,000 flights. Such incidents emphasize the need for stronger redundancy measures in major travel hubs to prevent prolonged operational shutdowns.

Why Was the Power Outage So Disruptive?

Airports rely on highly complex power systems to manage air traffic control, security, check-in services, and aircraft operations. A sudden power failure can bring airport activity to a standstill, with cascading effects that last for days.

At Heathrow, the outage disrupted baggage handling systems, leaving thousands of pieces of luggage stranded. Check-in services and security screening were severely impacted, creating long queues and further delays. Runway lighting and navigation systems were affected, causing inbound flights to be diverted to other UK airports. Communications within air traffic control were also disrupted, complicating coordination between ground and flight operations.

Despite backup power generators, an airport of Heathrow’s scale cannot fully restore operations immediately. The recovery process is complicated by the need to reposition aircraft and crews, with limited spare resources available.

How Is Heathrow Working to Prevent Future Outages?

The Heathrow shutdown has renewed concerns over the airport’s reliance on external power infrastructure. While modern airports typically have backup generators, the fact that this outage lasted for nearly a full day suggests that existing redundancies were insufficient.

Industry experts have pointed out that Heathrow’s reliance on a single regional power grid increases its vulnerability to large-scale failures. To prevent similar incidents in the future, aviation analysts recommend strengthening backup power systems by integrating isolated microgrids, which would allow Heathrow to maintain core operations independently of external substations. Enhanced crisis response protocols could also be implemented to minimize downtime in emergency situations. Some experts suggest that diversifying energy sources by incorporating renewable energy storage, such as solar power with battery backup, could reduce Heathrow’s dependence on traditional power infrastructure.

What Should Passengers Expect in the Coming Days?

Despite Heathrow’s phased reopening, delays are likely to continue into the weekend and possibly beyond. Airport officials strongly advise passengers not to travel unless their airline has explicitly confirmed their flight status. British Airways and other airlines are working to rebook affected passengers, but with limited availability and high demand, many travelers will face long wait times.

Passengers planning to travel in the coming days should check flight updates regularly through airline websites and mobile apps. Those who must fly should arrive at the airport early to allow extra time for security and check-in, as congestion remains high. Travelers should also be prepared for baggage delays, as airport staff work to process the backlog of luggage caused by the disruption.

As Heathrow works to restore normalcy, this incident underscores the vulnerabilities in global air travel infrastructure. The increasing demand for efficient airport operations requires stronger contingency plans to ensure that a single infrastructure failure does not bring an international travel hub to a standstill.