What we know about the massive staffing shortage that has caused 7 days of major delays at Newark Airport

The FAA Air Traffic Control tower at Newark Liberty International Airport in Newark, New Jersey, is shown in March 2024.

For years, the shortage of certified air traffic controllers in the US has led to flight disruptions and headaches for travelers across the country, most recently at busy Newark Liberty International Airport in New Jersey, where staffing issues have led to major delays for an unparalleled seventh day in a row.

The Federal Aviation Administration on Sunday implemented a Ground Delay Program and flights were delayed an average of almost four hours Sunday evening, according to an advisory from the FAA.

Multiple accumulating factors seem to have caused the massive delays, including the nationwide air traffic controller shortage; a walk-off by Newark air traffic controllers last week, according to United Airlines CEO Scott Kirby; the closure of a runway for “rehabilitation work;” and technology failures caused by outdated equipment, according to Secretary of Transportation Sean Duffy.

The control facility responsible for traffic at Newark has been “chronically understaffed for years,” Kirby said in a Friday message addressing the delays.

One flyer, Geraldine Wallace, told CNN Sunday she is anxious about the staffing shortage after her flight was delayed for almost three hours.

“I hope it can be resolved,” she said.

Since last Monday, the FAA has cited staffing as the cause of delays, but has not commented officially on the nature of the staffing problems at Newark Airport.

Here’s more on what we know about the historic delays.

Technical failures

Just outside of New York City, Newark is typically a bustling airport, ranked the 14th busiest airport in the country in 2024, according to the Department of Transportation’s Bureau of Transportation Statistics. It’s a major hub for United Airlines, which on Sunday delayed 232 flights and canceled 35 more, according to the tracking website FlightAware, leaving passengers with the option to reschedule.

Kirby, the United Airlines CEO, also said the airport’s issues seem to stem in part from technology failures.

On multiple instances in the past week, “technology that FAA air traffic controllers rely on to manage the airplanes coming in and out of Newark airport failed – resulting in dozens of diverted flights, hundreds of delayed and canceled flights and worst of all, thousands of customers with disrupted travel plans,” Kirby said.

Transportation secretary Duffy tied the technology failures to an outdated technology system used across the air traffic control facility at a Friday news conference. He pledged to implement a new, “state-of-the-art” system at air traffic control facilities across the country that would be the “envy of the world” – but said it might take three to four years.

The system used to manage air traffic at Newark is “incredibly old,” Duffy said.

“We use floppy disks. We use copper wires,” he said. “The system that we’re using is not effective to control the traffic that we have in the airspace today.”

He said the existing system is safe, but that its age results in the delays and cancellations now plaguing passengers.

President Donald Trump “is fully on board” with the plan to replace the systems, Duffy added. He called on Congress to “give us the resources” needed to upgrade the technology.

“We’re going to do this, rebuild a brand-new system, as we’re having airplanes take off and land,” he said. “We can do it – we’re America – but it’s going to take some time.”

Yearslong staffing shortage

The technology failures are compounded by the nationwide air traffic controller staffing shortage. Additionally, according to United CEO Kirby, “over 20% of the FAA controllers for EWR (Newark Liberty International Airport) walked off the job.”

The US needs more than 3,000 new air traffic controllers to reach adequate staffing, according to the National Air Traffic Controllers Association, a union representing 10,800 professional controllers.

“Keep in mind, this particular air traffic control facility has been chronically understaffed for years and without these controllers, it’s now clear – and the FAA tells us – that Newark airport cannot handle the number of planes that are scheduled to operate there in the weeks and months ahead,” Kirby said.

The Association of Flight Attendants-CWA, which represents 55,000 flight attendants, called on all airlines operating out of Newark to cut planned flights due to the staffing shortage.

“We support every effort to secure the funding necessary to staff up and provide the resources that are a decade overdue for our air traffic controllers to be able to do their jobs,” Sara Nelson, international president of AFA-CWA, said in a statement.

The new staffing-related delays are just the latest development in problems plaguing the Newark airport as a busy summer travel season is fast approaching. Last July, the FAA relocated a key control facility responsible for Newark air traffic from Long Island to Philadelphia in hopes of enticing new hires to join the understaffed facility.

A CNN analysis of FAA airspace advisories shows at least 14 straight days of FAA-imposed delays for flights to or from Newark. The airport is also in the middle of a runway rehabilitation project that is regularly closing one of its main runways until mid-June.

Nationwide staffing is at its lowest point in nearly 30 years, Nick Daniels, president of the controllers union, testified before Congress in March.

The most recent data from the FAA shows across all airport towers and terminal approach facilities nationwide, only about 70% of staffing targets were filled by fully certified controllers as of September 2023. When controllers in training are included, that rose to about 79%.

Despite various initiatives to pick up the pace of hiring and increasing the starting salary for Academy trainees by 30%, hiring and retaining air traffic controllers is tough due to strict certification requirements and burnout due to long hours and the stressful nature of the job, in addition to outside factors like the economy and government shutdowns.

In one attempt to reduce the shortage, a new incentives program will offer bonuses to students who successfully complete their training at the National Air Traffic Controllers Association, bonuses to new graduates training at hard-to-staff or high-cost-of-living programs, and 20% yearly bonuses to controllers who are eligible for retirement but stay on the job.

“The controllers here are committed to finding the solutions, but that only happens when we all sit down and work together,” Daniels said at the Friday news conference.

How bad is it?

Over a third of inbound and outbound flights at Newark were delayed Sunday, and more than 10% were canceled.

Wallace, a passenger whose flight was delayed while heading home to Canada, told CNN her outgoing flight from Newark was originally scheduled for 2:15 p.m. ET but was pushed until 5 p.m. ET.

Air traffic controllers “have the most critical job for our safety,” she said. “And so if they are understaffed and the people that are covering are going to be overtired, they’re doing longer shifts, as a flyer, that’s making me feel very nervous, actually.”

Her partner, Mark Wallace, said Sunday he was more worried about equipment failures than the staffing shortage.

“As concerning as the manpower issue is, according to news reports, the equipment that they’re using out of Philadelphia is antiquated,” he said. “That gives me probably even more concern.”

Another traveler, Michael Tassone, said he was “scrambling” to get home after his flight out of Newark was delayed multiple times before ultimately being rescheduled.

“There’s been a lot of scary news around air accidents this year, so hearing something like that is scary, but it’s not something you think about all the time when you book flights,” he told CNN Sunday. “You just trust that these airlines have everything under control, but I guess that’s now something you need to plan for.”

The decades-old staffing problem has experienced renewed public scrutiny after a series of collisions and near misses in the skies, including the January 29 midair collision of American Airlines Flight 5342 with a Black Hawk helicopter, which killed 67 people.

“We have a team up there right now. They’re doing an ongoing investigation into the technology, the interruption itself,” FAA Acting Administrator Chris Rocheleau said during a Thursday news conference announcing the Trump administration’s latest incentives to hire new air traffic controllers.

“At the end of the day, we need to make sure the controllers have the proper equipment and that they’re obviously appropriately staffed,” Rocheleau said.

The FAA is using delays to slow the number of flights so the system remains safe, according to Rocheleau.

“We saw a tragic accident,” Daniels said Friday. “No one wanted to see that tragic accident, and leaving it without action will leave it a tragedy.”

“Now we’re taking the action to turn it from a tragedy into a moment of progress that can honor the lives that were lost,” he said.

Chris Boyette, Pete Muntean and Zoe Sottile, CNN