Wow: Heathrow Airport Closed Following Fire, Power Outage

Well here’s something you don’t see every day. One of the world’s biggest airports will be closed for all of Friday, which will have impacts on aviation globally.

Heathrow Airport closed all day Friday, March 21

London Heathrow Airport (LHR) is closed for the entire day on Friday, March 21, 2025, and isn’t accepting any arrivals or departures. This is a result of a huge fire breaking out at a nearby electrical substation, which wiped out power to the airport. The cause of that is still being investigated. If you’re scheduled to fly from or through Heathrow today, of course don’t bother going to the airport.

We’ve seen a huge number of diversions as a result of this closure, including for transatlantic flights. The logistics here are just a total nightmare. In some cases, planes returned to their origin, while in other cases, they’ve had to divert to other airports.

As one example, one of last night’s American flights from Dallas (DFW) to London ended up first diverting to Bangor (BGR). Then when it was clear that Heathrow wouldn’t be reopening anytime soon, the plane continued to Boston (BOS), so that passengers would at least be stranded at a major station, and in the United States.

Cirium, the aviation analytics company, estimates that as many as 145,000 passengers could be directly impacted by this disruption. British Airways is obviously most impacted by this, as Heathrow’s largest airline. The carrier has released the following statement:

“Due to a power outage in the London Heathrow area, London Heathrow Airport is currently closed. As a result, customers due to travel from Heathrow on Friday are advised not to travel to the airport until further notice. This will clearly have a significant impact on our operation and our customers and we’re working as quickly as possible to update them on their travel options for the next 24 hours and beyond.”

Heathrow Airport hopes to reopen Saturday, March 22

Heathrow hopes to reopen for operations tomorrow, Saturday, March 22, 2025. However, that’s far from a sure bet at this point. Furthermore, even when operations do resume, expect that it won’t immediately be smooth sailing.

After all, there’s a huge domino effect to irregular airline operations, with planes and crews out of place. It’ll likely be several days before operations at Heathrow are fully back to normal.

Even if you have no plans to travel to or from Heathrow, you can expect that your journey may still be impacted by this disruption, given how planes cycle through networks. It could be that you’re scheduled to fly from Dallas to Sao Paulo, but your aircraft was supposed to originate in London, and is stuck there. So be extra vigilant in monitoring your travels over the next day or so.

Bottom line

London Heathrow Airport is closed today, Friday, March 21, 2025. This is due to a fire that broke out at an electrical substation, which is causing a power outage at the airport. This obviously has major implications not just for traffic at Heathrow, but also for airlines globally. So if you’re traveling over the next couple of days, be aware that this could impact your journey.

Any OMAAT readers impacted by this Heathrow outage?