London's Heathrow Airport warns of 'significant' disruption as it reopens after fire. What rights do U.S. travelers have?

Hundreds of thousands of passengers faced flight cancellations or turnarounds Friday after a fire caused a major power outage at London’s Heathrow Airport, one of the world’s busiest airports.

While Heathrow officials originally said the airport would stay closed until at least midnight, the airport announced just before 12:30 p.m. ET that it would be able to restart some flights. “We hope to run a full operation tomorrow,” airport officials said.

More than 1,300 flights have been affected today by the fire, flight tracking website Flightradar24 estimates — including 120 that were already in the air this morning before Heathrow officially shut down.

"We expect significant disruption over the coming days and passengers should not travel to the airport under any circumstances until the airport reopens," Heathrow said in a statement earlier Friday.

New York City’s John F. Kennedy International Airport is the busiest travel route out of Heathrow. According to Flightradar24, around 146 flights depart Heathrow for JFK each week. As of Friday morning, eastern time, five out of eight flights scheduled to leave JFK for Heathrow later today had already been canceled, and all eight flights arriving at JFK from Heathrow were canceled. Several flights that took off from JFK to Heathrow this morning have been diverted to airports in Manchester, England, Glasgow, Scotland, or Reykjavik, Iceland, while others have returned to New York.

What began as a local fire at an electrical substation near Heathrow that was called in late Thursday night spread and knocked out power to the airport and thousands of homes in western London. The cause of the fire has not been identified, the London Fire Brigade said Friday morning, but the organization would be further investigating what happened.

London Mayor Sadiq Khan told Sky News that while counterterrorism police are leading the investigation, there is “no reason at all for anyone to be concerned or alarmed” that this was a result of foul play.

Follow Yahoo News U.K.’s live blog for live updates on the Heathrow Airport shutdown.

Travel ‘nightmare’ for Americans

Comedian Adam Conover shared on X that he was traveling to Heathrow from Los Angeles to kick off the European part of his tour, with a show in London tomorrow night.

“90 minutes flight to London, captain comes on and says we're going back to LAX because there's a fire at a substation near Heathrow, which is now closed for 24 hours,” Conover wrote. “I have to figure out a new way to get to London immediately or cancel my show.”

One self-described “nervous father” said his son was in London with friends for spring break and was due to fly out of Heathrow within hours on Friday. “Ugh… what a nightmare,” he wrote on X.

A passenger aboard an American Airlines flight from Charlotte, N.C., to Heathrow recorded the moment the flight’s captain announced they were turning around.

“Something you may have noticed on a TV screen — we have made a 180-degree turn. We are headed back to Charlotte,” the pilot says. “They are not accepting flights into London Heathrow for the next 22 hours.”

A group of Arizona high school students flying through Heathrow after spending a week in Italy told the New York Times the airport shutdown delayed their travel plans.

“We didn’t find out the flight was canceled until half of our party had checked in,” Angel Brady, a chaperone on the trip, said. She lamented that the group would now miss their connecting flight back to Phoenix.

U.S.-based airlines offer travel waivers for affected travelers

Heathrow is a base for almost 90 airlines, including U.S.-based ones like Delta Air Lines, American Airlines, JetBlue, United and Virgin Atlantic.

Virgin Atlantic asked customers to “not travel to Heathrow” or “contact our customer centre at this time” and instead check flight statuses online.

“We’re incredibly sorry for the disruption this will cause and are working with our teams to ensure customers can complete their journeys as quickly as possible.”

Delta, American Airlines and JetBlue have issued travel waivers for passengers who are affected by flight disruptions, with Delta waiving all fare differences for reissued tickets if they’re rebooked by March 26.

I’m an American traveler affected by the Heathrow cancellations. What are my rights?

You could be covered by British law “UK261,” depending on where you were traveling from and with what airline, even as an American citizen. UK261 grants the right to compensation and assistance for travelers who are dealing with issues like flight delays or cancellations.

Under UK261, airlines have to provide food and drink, communication, transportation and accommodation for passengers “until it is able to fly you to your destination, no matter how long the delay lasts or what has caused it.”

You can check whether the U.K. law applies to your specific flight incident here and here. It’s been recommended that you keep as many receipts as possible for potential future reimbursement while the travel chaos with Heathrow is resolved.