What airlines are grounded by the worldwide tech outage?

In the U.S., the FAA said Thursday night that United, American, Delta and Allegiant had all been grounded by the outage, although the airlines have begun saying Friday that service was coming back online. 

American resuming flights

Around 5 a.m. Friday, American Airlines posted to X, formerly Twitter, saying that they had restored service, and thanked customers for their patience. 

"Earlier this morning, a technical issue with a vendor impacted multiple carriers, including American," the airline's post read. "As of 5:00 a.m. ET, we have been able to safely re-establish our operation. We apologize to our customers for the inconvenience."

It's unclear how many American flights were delayed or canceled because of the overnight grounding. 

United offers waiver to change travel plans

While United Airlines flights remain grounded, the company said it was offering ways for customers to change their plans to account for the delays caused by the outage. 

In a statement, United said they were working to restore services, and "some flights are resuming."

"A third-party outage is impacting computer systems, including at United and many other organizations worldwide," the statement reads. "As we work to fully restore these systems, some flights are resuming. Many customers traveling today may experience delays. We have issued a waiver to make it easier to change your travel plans at United.com or the United app."

Travelers sleep in airports as flights delayed

Travelers at Los Angeles International Airport slept on a jetway floor, using backpacks and other luggage for pillows, due to a delayed United flight to Dulles International Airport early on Friday.

Flight tracking website FlightAware showed that 1,297 flight delays into, out of or around the U.S. had been reported Friday morning. 

Around 722 flights in the U.S. had been canceled completely, the website shows. 

Delays around the globe

British systems appeared to be hit hard by the outage, with budget airline Ryanair asking travelers to arrive three hours before their flight. 

“We’re currently experiencing disruption across the network due to a global third party IT outage which is out of our control,’’ Ryanair said. “We advise all passengers to arrive at the airport at least three hours before their scheduled departure time.”

Edinburgh Airport in the U.K. said the system outage meant waiting times were longer than usual. London’s Stansted Airport said some airline check-in services were being completed manually, but flights were still operating.

Widespread problems were reported at Australian airports, where lines grew and some passengers were stranded as online check-in services and self-service booths were disabled. Passengers in Melbourne queued for more than an hour to check in, although flights were still operating.

Airline operations in India were disrupted, affecting thousands.

The privately-owned IndiGo airlines told the passengers on X that the Microsoft outage on Friday impacted airline operations in India, inconveniencing thousands of passengers.

Zurich Airport, the busiest in Switzerland, suspended landings on Friday morning but said flights headed there that were already in the air were still allowed to land. It said that several airlines, handling agents and other companies at the airport were affected, and that check-in had to be done manually in some cases, but that the airport’s own systems were running.

At Rome's Leonardo da Vinci airport, some US-bound flights had posted delays, while others were unaffected.

Manual check-in process working but slow

Several airlines made statements on X saying that they were following manual check-in and boarding processes and warned of delays due to technical problems.

Hong Kong’s Airport Authority said in a statement that the outage was affecting some airlines at the city’s airport and they had switched to manual check-in.

Amsterdam’s Schiphol Airport said on its website that the outage was having a “major impact on flights” to and from the busy European hub. The outage came on one of the busiest days of the year for the airport, at the start of many people’s summer vacations.

In Germany, Berlin Airport said Friday morning that “due to a technical fault, there will be delays in check-in.” It said that flights were suspended until 10 a.m. (0800GMT), without giving details, German news agency dpa reported.