CHICAGO - The planned shutdown of nearly 240 air traffic control towers across the country under federal budget cuts will strip away an extra layer of safety during takeoffs and landings, leaving pilots to manage the most critical stages of flight on their own.
The towers slated to close are at smaller airports with lighter traffic, and all pilots are trained to land without help by communicating among themselves on a common radio frequency. But airport directors and pilots say there is little doubt the removal of that second pair of eyes on the ground increases risk and will slow the progress that has made the U.S. air system the safest in the world.
It's not just private pilots in small planes who stand to be affected. Many of the airports in question are serviced by major airlines, and the cuts could also leave towers unmanned during overnight hours at some big-city airports such as Chicago's Midway and General Mitchell Airport in Milwaukee. The plans have prompted airlines to review whether the changes might pose problems for commercial service that could mean canceling or rescheduling flights.
Without the help of controllers, risk "goes up exponentially," said Mark Hanna, director of the Abraham Lincoln Capital Airport in Springfield, Ill., which could see its tower close.
As part of the spending cuts that went into effect this month, the Federal Aviation Administration is being forced to trim $637 million for the rest of the fiscal year that ends Sept. 30. The agency said it had no choice but to subject most of its 47,000 employees, including tower controllers, to periodic furloughs.
Representatives of the FAA declined to discuss the effect of the cuts with The Associated Press. In two recent speeches and testimony before Congress, FAA Administrator Michael Huerta stressed that safety remained the agency's top priority. But many in the aviation sector are frustrated that the political brinkmanship in Washington has affected such a sensitive area of aviation.
Jim Montman, manager of the Santa Fe Municipal Airport, which is on the list for tower closures, said the absence of controllers raises the risk of midair collisions "or some sort of incident where somebody lands on the wrong runway. ... That critical link is gone."
Hundreds of small airports around the country routinely operate without controllers, using procedures in place since the earliest days of aviation. Pilots are trained to watch for other aircraft and announce their position over the radio during approaches, landings and takeoffs.
But past crashes, however rare, have exposed weaknesses in that system.
The 238 air traffic control facilities that could be closed were chosen because they are at airports with fewer than 150,000 flight operations per year. They are located in nearly every state.
The first round of closures is expected to target 173 of those towers that are run by third-party contractors, rather than FAA staff. That process could start early next month.
Tucson's Ryan Airfield is on a list regulators released in early March of smaller airports that face possible tower closures because of federal sequestration cuts.
The Federal Aviation Administration sent letters to operators of 189 small airports, including Ryan, saying their contractor-operated control towers face closure unless they can show that keeping them open is in the national interest.
The Tucson Airport Authority has sent letters to the FAA and Arizona's congressional delegation, supporting Ryan's tower operation.
Even if the control tower is closed, Ryan Airfield will remain open for flight operations coordinated via radio by pilots, which is how operations are now conducted at night when the tower isn't staffed.