Air traffic control problems continued at Newark Liberty International Airport on Sunday morning after an equipment glitch, officials said.

The United States aviation industry continues to grapple with the worst air traffic controller shortage in nearly 30 years as a recent spate of incidents has thrust the high-stress profession into the spotlight.

A reporter asked Duffy on Monday why the first Trump administration chose not to address the air traffic control system during his first term in office, noting that Duffy said it was a “decades-old” problem. However, Duffy’s answer left many users on social media scratching their heads.

One air traffic controller (ATC) and a trainee will operate every flight in and out of Newark between 6.30pm-9.30pm — despite 15 staffers being the standard requirement for a shift.