Flight cancellations are spiking in part because this air traffic control center in Florida is severely understaffed, airline group says

• The Air Lines Pilots Association (ALPA) expressed concern about staffing at air traffic control centers.
• The group pointed to a center in Jacksonville, saying it has been understaffed for 27 of the past 30 days.

A US airline lobbying group is calling on the federal government to address air traffic control staffing ahead of the busy July 4 holiday weekend.

In a letter sent to Transportation Secretary Pete Buttigieg on Friday, Airlines for America said one of its member carriers estimated that air traffic control (ATC) issues contributed to at least one-third of recent US flight cancellations. The letter was viewed by Insider.

The stat comes after chaotic key holiday weekends in May and June; more than 35,000 flights were disrupted over the Juneteenth weekend.

A4A blamed staffing in part, saying ATC shortages have "led to traffic restrictions under blue sky conditions."

The group specifically pointed to the Jacksonville Air Route Traffic Control Center in Florida, which the Air Line Pilots Association says has been understaffed for 27 of the last 30 days. The facility oversees air traffic in Alabama, Georgia, Florida, and North and South Carolina, controlling about 250 military and civilian airports, according to the Federal Aviation Administration.

In May, the FAA met with airlines to discuss the issues, and the agency committed to "immediately increase the number of authorized staff at Jacksonville Center and evaluate other Florida facilities."

According to a source familiar with the FAA's hiring plan, 30 new controllers have been hired at the center as of June 17, local Jacksonville news station News4JAX reported. The FAA confirmed to Insider that additional controllers have been added to the team in Jacksonville, but did not give a specific number.

The agency also said in a comment that there is "not a system-wide air traffic controller shortage" and that the driving factor for delays and cancelations in Florida is convective weather and demand to travel to the state. Moreover, the agency said there will be no space launch during the Fourth of July weekend and that it has "added alternate routes and placed more controllers in high demand areas."

Henry Harteveldt, travel analyst and president of Atmosphere Research Group, told Insider that hiring is a big challenge for the FAA because of the long process, which includes interviews, training, and drug tests. However, he said the agency needs to do a better job of recruiting young people.

The FAA has made efforts to find more candidates in recent weeks, including launching its "Be ATC" campaign to "hire the next generation of air traffic controllers." The application process opened June 24 to eligible US citizens, but the window of opportunity is open only through June 27.

Other ATC centers in the US also have had problems. John Lucia, an officer at the FAA's Air Traffic Control System Command Center, told CNBC that thunderstorms threatened to clog traffic at the Dallas/Fort Worth and Dallas Love Field airports.

Meanwhile, United CEO Scott Kirby said in an interview with Bloomberg that ATC staffing at its Newark Liberty International Airport hub has caused significant flight disruptions.

"We have had weekends recently where [ATC] is under 50% staffing and the controllers are working their tails off to be successful," he said. "But, when you're at 50% staff with 89 operations in schedule and they had us on a perfectly blue sky day at 36 operations per hour, it is a nightmare for customers, for employees, for the airlines."