The Federal Aviation Administration released new rules Wednesday designed to prevent airline pilots from flying when they're too tired.
The FAA regulations limit the number of hours a pilot can be scheduled to fly to between nine and 14 hours at a time, depending on the time of day.
Safety advocates, who have been pushing to have flying regulations revised for more than two decades, applauded the move.
The changes replace, "Rules that were dangerously obsolete and completely ineffective," said Bill Voss, president of the Flight Safety Foundation in Alexandria, Va. "The rule applies fatigue science in a way that makes sense."
Experts say flying while fatigued can lead to slowed reflexes and poor judgment. Some even liken fatigued flying to flying drunk.
Airlines will have two years to adjust to the new regulations, a process the FAA estimates will cost the industry $297 million over a decade.
"We made a promise to the traveling public that we would do everything possible to make sure pilots are rested when they get in the cockpit. This new rule raises the safety bar to prevent fatigue," Transportation Secretary Ray LaHood said in a statement.