Airlines have yet to say whether they will continue offering service to airports that lose tower staff.
The 149 air traffic facilities slated to begin closing on April 7 are all staffed by contract employees who are not FAA staffers. There were 65 other facilities staffed by FAA employees on the preliminary list of towers that could be closed. A final decision on their closure will require further review, the FAA said.
The agency is also still considering eliminating overnight shifts at 72 air traffic facilities, including some at major airports like Chicago's Midway International and General Mitchell Airport in Milwaukee. There was no word Friday on when a decision will come.
Hundreds of small airports around the country routinely operate without controllers. Pilots are trained to watch for other aircraft and announce their position over the radio during approaches, landings and takeoffs.
But the overall air system's safety is built on redundancy, and taking away the controller's extra set of eyes is like removing stop signs or traffic lights from city intersections and forcing drivers to be more vigilant and cautious, says Paul Rinaldi, president of the National Air Traffic Controllers Association.
"That's what the pilot is going to have to do now," said Rinaldi, whose group represents nearly 15,000 FAA-employed controllers as well as some staff at privately run contract towers that were the subject of Friday's announcement.
"A pilot is now going to have that extra duty of making sure that everybody seems to be doing the right thing on a crowded" frequency, he said.
And pilots will have to do that on top of flying the airplane or maneuvering it on the ground, "which is not an easy thing to do," Rinaldi added. "It's not like driving a car."