Mass flight cancellations rocked U.S. airports for a third straight day Sunday, as the lingering fallout from a technical glitch Friday affecting Microsoft Windows clients caused IT infrastructure outages worldwide and disrupted many flight operations, even prompting an apology from the CEO of Delta Air Lines Sunday afternoon.
Delta and United Airlines again canceled hundreds of flights Sunday as both carriers continued to work to resume operations following problems caused by a third-party vendor late last week.
The problems led to crowded terminals at airports across the country this weekend, with long, winding lines of travelers waiting to speak to customer service, and images of passengers sleeping on the floors of airport concourses.
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As of Sunday afternoon, airlines had canceled more than 1,200 flights in the United States.
According to data from flight tracking site FlightAware, Delta led the way with more than 700 cancellations Sunday, or nearly a fifth of its business. United was second with 259 cancellations Sunday, or about 8% of its schedule.
In total, airlines have canceled more than 6,700 flights in the United States since Friday’s disruption, including nearly 3,200 on Delta, according to data from FlightAware.
In a note to customers Sunday afternoon, Delta CEO Ed Bastian apologized for the extended disruptions.
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“Delta is in the business of connecting the world, and we understand how difficult it can be when your travels are disrupted,” Bastian said. “Thank you for your patience as we work to resolve these issues, restore our operations, and return to the reliability you expect from Delta.”
Delta Airlines
The Atlanta-based carrier said Sunday it was still getting operations back on track after the computer outage at Austin-based Crowdstrike forced it — and several other U.S. airlines — to temporarily suspend flights Friday.
The problems affected the Microsoft Windows operating system that runs many of Delta’s applications, Bastian said. The problems affected a key crew tracking tool, he added, leaving the airline unable to “effectively process the unprecedented number of changes” triggered by the shutdown.
Bastian said the problems were compounded by the fact that the disruptions came 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 in the country.
Flights for unaccompanied minors suspended
Delta extended its pause on unaccompanied minor flights through Tuesday (July 23) and extended travel waivers that allow passengers more flexibility to change their itineraries — a move taken by other affected carriers, including United.
How Delta reacts
Delta said Sunday it would provide meal vouchers, hotel rooms and transportation to affected customers as needed. And, “as a form of apology,” Bastian said, the airline will provide customers with travel vouchers and Delta SkyMiles.
DOT Refund Policy
Keep in mind that, under U.S. Department of Transportation policy, travelers whose flights are canceled or significantly delayed are entitled to a refund — to their original form of payment — for the unused portion of their ticket if they ultimately choose not to fly and do not accept a rebooking.
Technological challenges persist
Delta says customers can monitor and manage itinerary changes on the airline’s website and mobile app. However, the carrier noted that those tools “were inundated with traffic, resulting in intermittent performance issues.”
The airline said it was working to stabilize those tools and warned that its ability to respond to social media messages was also limited.
United Airlines
In its latest update 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 further cancellations and delays likely over the weekend.
U.S. flight cancellations on Saturday were down 37% from Friday, according to data from FlightAware, but still topped 1,600 for the day, led by Delta at 1,200.
Delta and United’s major hubs were 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 issues originated with a third-party vendor, and not the airlines directly, the U.S. Department of Transportation considers these cancellations and delays to be “controllable” — in other words, the airline’s responsibility — an agency spokesperson told TPG Friday.
That means the promises airlines make, as outlined in the airlines’ customer service dashboard, will apply. Here’s what each airline told the DOT they would guarantee after a cancellation or significant delay.
Other important resources:
Transportation Secretary Pete Buttigieg took to social media Saturday to reiterate the agency’s reimbursement policies.
“I’ve heard that some airlines are only offering flight credits,” Buttigieg wrote on X, formerly Twitter. “Let me be clear: you have the right to get your money back quickly if your flight is canceled and you don’t rebook.”
An outlier in 2024
The operational disruptions over the past 48 hours come during a year that has been largely without a major air travel crisis.
Between January 1 and July 18, U.S. airlines canceled 1.3% of flights, according to FlightAware. That compares to a cancellation rate of 2.6% during the same period in 2022.
Delta particularly touted its operational reliability during the carrier’s second-quarter earnings call on July 11. The carrier has performed well in recent J.D. Power airline rankings and TPG’s 2024 Best Airlines report, thanks in part to its operational reliability.
The industry’s most recent large-scale operational issues include a multi-day incident at United last summer that prompted the carrier to step up its work with the Federal Aviation Administration on operations at Newark… and an FAA computer outage in January 2023 that led to the first nationwide grounding since Sept. 11, 2001. The latter incident came just days after Southwest Airlines’ operational disaster during the 2022 holiday season.
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