Wayne Minnick, a former air traffic controller who runs a consulting business in Missouri, said it's common for controllers who have a quick shift turnaround to get little to no sleep.
"The quick turnaround, like having nine hours off between shifts, that happens all the time," said Minnick, who was a controller for 22 years. "Sometimes you try to grab two to three hours between shifts when you have a quick turnaround like that."
Two years ago, Los Angeles International Airport's control tower was understaffed by about half the normal level when a tired air traffic controller was involved in the near-crash of two airliners, according to safety investigators.
The controller positioned a Southwest Airlines Boeing 737 on the same runway where an Asiana Airlines jumbo jet had been cleared to land. The Asiana pilot saw the Southwest jet and pulled up as alarms sounded in the control tower. The airplanes missed each other by 200 feet.
Dr. Charles Czeisler, professor of sleep medicine at Harvard Medical School, said the Lexington controller's sleep deprivation meant it was likely he suffered attention lapses and he took three times as long to react to things.
For the average person who's been on duty for 17 of the previous 24 hours and has had two hours of sleep, "the impairment is comparable to being legally drunk," Czeisler said.