Former and current U.S. air traffic controllers say the Trump administration's focus on new equipment doesn't address problems like grueling schedules and stagnating pay that are hurting morale.

U.S. Transportation Secretary Sean Duffy praised airport officials, unions and workers for completing the estimated 60-day project 13 days early. The Newark airport has been hobbled by delays.

At a Senate hearing, aviation experts testified that a shortage of air traffic controllers is leading to fatigue and distraction, likely contributing to a series of close calls on runways this year.