(AP)—U.S. air traffic controllers are still working schedules that make it likely they will get little or no sleep before overnight shifts, more than three years after a series of incidents involving controllers sleeping on the job, according to a government-sponsored report released Friday.
The report by the National Research Council also expressed concern about the effectiveness of the Federal Aviation Administration's program to prevent its 15,000 controllers from suffering fatigue on the job, a program that has been hit with budget cuts.
The 12-member committee of academic and industry experts who wrote the report at the request of Congress said FAA officials refused to allow them to review results of prior research the agency conducted with the U.S. space agency examining how work schedules affect controller performance.
The FAA-NASA research results "have remained in a 'for official use only' format" since 2009 and have not been released to the public, the report said.
The committee stressed its concern that controllers are still working schedules that cram five eight-hour work shifts into four 24-hour periods. The schedules are popular with controllers because at the end of last shift they have 80 hours off before returning to work the next week.
An example of the kind of schedule that alarmed the report's authors begins with two consecutive day shifts ending at 10 p.m. followed by two consecutive morning shifts beginning at 7 a.m. The controller gets off work at 3 p.m. after the second morning shift and returns to work at about 11 p.m. the same day for an overnight shift—the fifth and last shift of the workweek.
When factoring in commute times and the difficulty people have sleeping during the day, controllers are "unlikely to log a substantial amount of sleep, if any, before the final midnight shift," the report said.
"From a fatigue and safety perspective, this scheduling is questionable and the committee was astonished to find that it is still allowed under current regulations," the report said.
FAA officials didn't immediately respond to a request for comment on the report.
In 2011, FAA officials and then-Transportation Secretary Ray LaHood promised reforms after a nearly a dozen incidents in which air traffic controllers were discovered sleeping on the job or didn't respond to calls from pilots trying to land planes late at night.
In one episode, two airliners landed at Washington's Reagan National Airport without the aid of a controller because the lone controller on the overnight shift had fallen asleep. In another case, a medical flight with a seriously ill patient had to circle an airport in Reno, Nevada, before landing because the controller had fallen asleep.
Studies show most night shift workers, not just controllers, face difficulties staying awake no matter how much sleep they've had. That's especially true if they aren't active or don't have work that keeps them mentally engaged. Controllers on night shifts often work in darkened rooms with frequent periods of little or no air traffic to occupy their attention—conditions scientists say are conducive to falling asleep.
"We all know what happens with fatigue," said Mathias Basner, an assistant professor at the University of Pennsylvania medical school and the sleep expert on the committee.
After the 2011 sleeping incidents, the FAA stopped scheduling controllers to work alone on overnight shifts at 27 airports and air traffic facilities and increased the minimum time between work shifts to nine hours.
Basner said the FAA was making no effort to determine whether there is a correlation between work schedules and controllers' errors.
The National Air Traffic Controllers Association defended the current scheduling, citing the 2009 study that hasn't been publicly released. The union said in a statement that NASA's research showed that "with proper rest periods," the schedule "actually produced less periods of fatigue risk to the overall schedule."
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