Charles Lindbergh famously fell asleep while crossing the Atlantic, and despite strict federal rules against it, experienced airline pilots say it's not uncommon to sneak a nap inside the cockpit.
The Northwest pilots who blew 150 miles past Minneapolis this past week insist a clandestine snooze isn't to blame for their goof at 37,000 feet. "Nobody fell asleep in the cockpit," first officer Richard I. Cole told The Associated Press.
Aviation safety experts and fellow pilots don't buy it, arguing the most likely explanation for missing more than an hour of radio, cell phone and data messages is a drowsy flight crew. The prospect alone could renew focus on pilot fatigue and research that suggests controlled catnaps might actually make flying safer.
"If you really need a nap, you're far better off taking a nap than ignoring your body and being tired during takeoff and landing," said Kit Darby, a pilot who said he took the occasional mid-flight nap during his 30-year career at several major airlines.
"It was not uncommon to do that. If you needed to take a nap, you took a nap," Darby said. "As a captain, I would encourage it."
International carriers including Air France, British Airways and Qantas allow pilots to nap, but sleeping while flying is prohibited at U.S. airlines by the Federal Aviation Administration. Just last month, the Air Transport Association again pressed the FAA to allow controlled cockpit napping, citing NASA research that found a mid-flight snooze significantly reduces the risks of overall pilot fatigue.
"Other regulatory agencies have endorsed it for many years with no adverse consequences," the group, which represents the major U.S. airlines, along with associations for regional and cargo airlines, wrote to Margaret Gilligan, the FAA's associate administrator for safety.
The NASA study begun in 1989 allowed one group of pilots flying across the Pacific to take a 25-minute nap while their co-pilots flew the planes, while a control group was required to remain awake for the entire flight. Those without the naps nodded off five times as much — including while on the approach to the airport — as those who got some sleep.
The research didn't sway the FAA, but it didn't go unnoticed among those pilots who break the agency's rules by catching some sleep while in the cockpit, said Curt Graeber, the former chief engineer for human factors in Boeing's commercial airplane division.
"We used to call it the NASA nap, or snooze cruise," he said.
FAA rules currently allow airline pilots to fly eight hours in a 16-hour "duty day," which includes briefings and other preparation time. Commercial airline pilots often make long, tiring commutes to reach their departure point; the pilots of the San Diego-Minneapolis flight live in Oregon and Washington state. Once on duty, pilots can sit for long hours behind a locked door minding a plane that is largely automated once they're airborne.
American Airlines pilot Sam Mayer said problems with fatigue are greatest among pilots who make several short trips a day, sometimes for three or four days in a row. Flight 188 captain Timothy B. Cheney and first officer Richard I. Cole had just started their work week and were coming off a 19-hour layover, the Minneapolis Star Tribune reported Saturday, citing an internal Northwest document it said was described to the newspaper.
Under their contract, American Airlines pilots who refuse to fly because they're tired are protected from retaliation. Skipping a flight means not getting paid for those hours, and Mayer said the Minneapolis incident "is more anecdotal evidence that pilots are fatigued out there."
On long international flights, a third pilot joins the flight crew so that one pilot can sleep while two remain at the controls. But Graeber said working a long-haul flight can be less tiring than flying a small commuter jet at low altitude on multiple takeoffs and landings on one shift.
"There's a lot more stress than flying a 747 with a bunk in the back," he said.
The NTSB plans to investigate whether fatigue was a factor and will interview the pilots next week. Northwest, acquired last year by Delta Air Lines Inc., has suspended Cheney and Cole and is also investigating.
An airport police report said the men were "cooperative, apologetic and appreciative" and volunteered to take tests that were zero for alcohol use. They told police they missed the airport because they had become distracted by a heated discussion, something retired Delta pilot Joe Mazzone said could have led them to miss a critical radio handoff between air traffic controllers.
"You're talking about 15 minutes if they were at 500 knots," Mazzone said. "It's not long at all."
But Mazzone, who flew jet airliners for 23 years, said it's just as possible they got caught napping.
"It's kind of like being in an operating room. You know the physicians and the nurses ... are listening to music, telling jokes, they're doing what keeps them alert," he said. "Things are happening that if the public knew about it, they wouldn't understand it, but it's done. They've got the same thing in the cockpit."