Mass flight cancellations paralyzed U.S. airports for a third straight day on Sunday, the fallout lingering after a technology glitch on Friday affecting Microsoft Windows clients caused disruptions to IT infrastructure around the world and It disrupted many airline operationswhich even prompted an apology from the CEO of Delta Air Lines on Sunday afternoon.
Delta and United Airlines canceled hundreds of flights again on Sunday as the two carriers continue to work to get their operations back on track following problems caused by a third-party vendor late last week.
The problems have caused airport terminals across the country to be packed this weekend, with long, snaking lines of travelers waiting to speak to customer service, and images of passengers sleeping on the floors of airport lounges a common sight.
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As of Sunday evening, airlines had cancelled more than 1,700 flights in the United States.
Delta led the list with more than 1,000 cancellations on Sunday, more than a quarter of its operation, according to data from flight tracking site FlightAware. United came in second, with 262 cancellations on Sunday, about 9% of its schedule.
In total, airlines have canceled more than 7,000 U.S. flights since Friday’s disruption, more than 3,400 of them by Delta, according to FlightAware data.
In a note to customers Sunday afternoon, Delta CEO Ed Bastian apologized for the extended disruptions.
“Delta is dedicated to connecting the world, and we understand how difficult it can be to have your travels disrupted,” Bastian said. “Thank you for your patience as we resolve these issues, restore our operations and return to the reliability you expect from Delta.”
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Delta has already canceled at least 155 flights scheduled for Monday.
Delta Air Lines
The Atlanta-based airline said Sunday it was still in the process of resuming operations following the computer outage at Austin-based Crowdstrike that caused it (and several other U.S. airlines) to temporarily pause flights on Friday.
Bastian said the issues affected the Microsoft Windows operating system, which is used in numerous Delta applications. The problems affected a key crew tracking tool, he added, leaving the airline unable to “effectively process the unprecedented amount of changes” brought on by the shutdown.
Bastian said the problems were made worse by the fact that the outages occurred during what was expected to be Delta’s busiest travel weekend of the summer.
Thursday was the third-busiest day on record at Transportation Security Agency checkpoints nationwide.
Unaccompanied minor flying on pause
Delta has extended its pause on unaccompanied minor flights through Tuesday (July 23) and expanded travel waivers that allow passengers more flexibility to make itinerary changes, a move taken by other affected airlines, including United.
How Delta is responding
Delta said Sunday it is offering meal vouchers, hotel accommodations and transportation to affected customers as needed. And, “as a gesture of apology,” Bastian said, the airline is providing customers with travel vouchers and Delta SkyMiles.
DOT Refund Policy
Please note that according to the U.S. Department of Transportation, policy, Travelers whose flight is cancelled or significantly delayed are entitled to a refund (via their original payment method) of the unused portion of their ticket if they ultimately decide not to fly and do not accept a new booking.
Technological challenges persist
Delta notes that customers can monitor and manage itinerary changes on the airline’s website and mobile app. However, the airline noted that these tools “have been inundated with traffic, resulting in intermittent performance issues.”
The airline said it is working to stabilize those tools and warned that its ability to respond to social media messages is also limited.
united airlines
In its most recent update on Saturday, United told TPG that its customer service call systems had been fully restored and noted that most technology systems were back up and running, but warned of additional cancellations and delays likely over the course of the weekend.
U.S. flight cancellations on Saturday were down 37% from Friday, FlightAware data shows, but still topped 1,600 for the day, led by Delta’s 1,200.
Delta and United’s major hubs have been among the hardest hit U.S. airports this weekend, from Hartsfield-Jackson Atlanta International Airport (ATL) to Minneapolis-St. Paul International Airport (MSP), Denver International Airport (DEN) and Newark Liberty International Airport (EWR), among others.
What do airlines owe you after a cancellation or delay?
Although the problems arose from a third-party vendor, not directly from the airlines, the U.S. Department of Transportation considers these cancellations and delays to be “controllable” — in other words, the responsibility of the airline, an agency spokesperson told TPG on Friday.
This means that the promises made by the airlines and detailed in the Airline Customer Service Panel would apply. Here’s what each airline has told the DOT it will guarantee after a cancellation or significant delay.
Other important resources:
Transportation Secretary Pete Buttigieg took to social media on Saturday to remind people of the agency’s reimbursement policies.
“I’m hearing that some airlines are only offering flight credits,” Buttigieg wrote on X, formerly Twitter. “I want to be clear: you have the right to get your money back quickly if your flight is cancelled and you don’t rebook.”
An atypical case in 2024
The operational disruptions over the past 48 hours come in a year that has largely passed without major crises in air travel.
According to FlightAware, between January 1 and July 18, U.S. airlines cancelled 1.3% of flights. Compare that to a cancellation rate of 2.6% during the same period in 2022.
Delta specifically touted its operational reliability during the airline’s campaign. Second Quarter Earnings Conference Call on July 11. The airline scored highly in both recent reports JD Power Airline Rankings and TPG’s Best Airlines of 2024 Report due, in part, to its operational reliability.
The industry’s most recent large-scale operational problems include a multi-day issue at United last summer that led the airline to… to intensify its collaboration with the Federal Aviation Administration on operations in Newark…and a FAA computer outage in January 2023 which caused the first nationwide grounding since Sept. 11, 2001. The latest incident came just days after Southwest Airlines’ 2022. Holiday operational disaster.
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