A veteran air-traffic controller at the facility that handles flights in and out of Newark Liberty International Airport is calling for more resources and speaking out about the intense pressures workers face amid a staffing shortage and tech outages.

A communications outage affecting flights approaching Denver International Airport is the latest in a series of glitches that have put a spotlight on the nation’s aging air traffic control system.

Another airport has been affected by aging air traffic control equipment. The air traffic control facility lost several radio channels that allowed them to communicate with pilots in and around Denver International Airport.