The summer travel season is heating up, and airlines are under pressure to avoid mass cancellations similar to what happened during the Memorial Day weekend.
U.S. airlines canceled high numbers of flights for a second straight day on Friday as they tried to recover from storms while accommodating growing crowds of summer vacationers.
By early afternoon in the eastern U.S., airlines had scrubbed more than 1,100 flights after canceling more than 1,700 on Thursday, according to tracking service FlightAware.
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Airports with the most cancellations were those in Charlotte, North Carolina, a major hub for American Airlines, LaGuardia and Newark Liberty in the New York City area, and Reagan Washington National outside Washington, D.C.
Flights departing from Palm Beach International Airport to Washington-DCA at 1:31 p.m., Atlanta at 2:26 p.m. and LaGuardia at 7:30 p.m. were canceled Friday, according to the airport's flight status website.
Transportation Secretary Pete Buttigieg held a virtual meeting with airline CEOs on Thursday to go over steps the airlines are taking to operate smoothly over the July 4 holiday and the rest of the summer, and to improve accommodation of passengers who get stranded when flights are canceled.
"I let them know that this is a moment when we are really counting on them to deliver reliably for the traveling public," Buttigieg told NBC News.
Buttigieg also pushed airlines to examine whether they can handle the schedules that they have published, and to improve customer service, the person said.
The head of trade group Airlines for America, Nicholas Calio, said in a statement that industry officials appreciated the chance to talk with Buttigieg and "discuss our shared commitment to prioritizing the safety and security of all travelers."
Airlines are struggling with shortages of workers, especially pilots, that are hurting their ability to operate all their planned flights. Pilot unions at Delta, American and Southwest have said their airlines were too slow to replace pilots who retired or took leaves of absence during the early part of the pandemic.
Two Senate Democrats said this month that the holiday weekend performance "raises questions about airline decision-making." Richard Blumenthal of Connecticut and Edward Markey of Massachusetts said delays and cancellations "are occurring so frequently that they are becoming an almost-expected part of travel."
On Friday, Allegiant Air, a discount carrier that caters to vacationers, said that although it is early, bookings for trips after the summer are running above this time in 2019.
Allegiant's update underscored a wild card still facing the airlines: COVID-19.
The Las Vegas-based airline said that as coronavirus cases began rising in mid-May, it canceled more flights because of absent crew members. Allegiant said those cancellations will cause second-quarter revenue to be at the low end of its previous forecast but still 28% higher than the same quarter in 2019.
U.S airlines experienced thousands of flight cancellations during the three-day Memorial Day weekend, causing travelers to be stranded at airports.
The airlines blame bad weather and the Federal Aviation Administration, an arm of the Transportation Department that manages the nation's airspace. In a letter to the senators, Calio ticked off a long list of FAA delays and staffing problems over the holiday weekend.
The airlines have jousted with the FAA this spring over delays in Florida, where air travel recovered more quickly than in many other parts of the country. After meeting with airline representatives in May, the FAA agreed to increase staffing at an air-traffic control center near Jacksonville and make other changes.
So far in June, more than 2.2 million travelers a day on average have gone through security checkpoints at U.S. airports. That's down 13% from the same period before the pandemic, according to the Transportation Security Agency.