A surge in callouts among air traffic controllers "is straining staffing levels" at multiple airports across the U.S. -- including in the New York City area where 80% of controllers are absent, the Federal Aviation Administration said Friday evening.

Air traffic controllers press lawmakers to end government shutdown, saying unpaid workers and staffing shortages are putting aviation safety at risk.

It's putting stress on people. It's not fair to those people. It's also putting stress on the economy,” United Airlines CEO Scott Kirby said.

With high winds expected to hamper East Coast hubs on Friday, air traffic controllers continue to call out of work in greater numbers after missing their first full paycheck—leading to further flight delays.