Nick Daniels, president of the National Air Traffic Controllers Association, said workers have gone too long without paychecks to work safely.

According to the FAA, it is highly competitive to become an air traffic controller, as candidates must be under 31 years old and pass yearly medical evaluations and multiple specialized tests, among other requirements. Controllers are also forced to retire at age 56.

The U.S. Federal Aviation Administration said on Friday it was delaying flights at eight airports including in Atlanta, San Francisco, Houston, Washington and Newark, citing widespread air traffic staffing issues as controllers have not been paid during the government shutdown.

The Salt Lake City International Airport is on the list of 40 major airports released by the US Department of Transportation with planned air traffic reductions starting Friday.

The Federal Aviation Administration (FAA) and the National Transportation Safety Board (NTSB) will lead the investigation into the incident.

French airport group ADP on Wednesday reported a 78.9% rise in first-quarter revenue as the travel industry recovers from the coronavirus crisis.

Apple Original Films has picked up The Flick, an unpublished short story from writer Matt Hickey set in the high-pressure world of air traffic control. Peter Chernin and David Rea