Studies: Cockpit napping by pilots not rare
Federal investigators are trying to determine whether two Northwest Airlines pilots fell asleep in the cockpit during a flight, prompting them to overfly their destination by 150 miles while air traffic controllers, other pilots and a flight attendant in the jetliner's cabin tried to get their attention.
Although Wednesday night's mistake is an uncommon one, cockpit napping by pilots isn't, according to studies and recent testimony before Congress.
"We don't know how much it really happens, but it's not infrequently," said Russell Rayman, executive director of the Aerospace Medical Association, based in Alexandria, Va.
The association in January published a report, "Fatigue Countermeasures in Aviation," that cited numerous studies indicating cockpit napping — even on some of the shortest domestic flights — was hardly rare.
Among the findings, 56 percent of regional airline pilots polled in a NASA survey said they had been on a flight where arrangements were made for one pilot to sleep while the other flew the plane. Another NASA study said pilots were observed napping 11 percent of the time during long-haul flights, with an average nod-off of 46 minutes.
"I'm not surprised (by such findings) at all," said frequent flier Keith Foley, 53, of Ellwood City.
"It's no different than a car, except this is up in the air and cars don't have autopilot. People make arrangements all the time for one person to drive while the other one sleeps. I'm sure the same thing goes on with pilots," Foley said.
Investigators don't know whether the Northwest pilots fell asleep, but National Transportation Safety Board spokesman Keith Holloway said Friday that fatigue and cockpit distraction will be looked into.
The plane's flight recorders were brought to Washington, but the cockpit voice recorder is an older model that contains only the last 30 minutes of conversation. That makes the investigation more difficult because that time would be taken up by the flight back to Minneapolis — the intended destination — and the landing there.
The pilots, temporarily suspended, are to be interviewed by investigators next week. The airline, acquired last year by Delta Air Lines, is investigating. The crew told authorities they were distracted during a heated discussion about airline policy.
Federal Aviation Administration rules don't allow cockpit napping.
The rules generally limit pilots on domestic flights to eight hours of flight time during any 24-hour period, though that can be extended depending on how much rest a pilot receives after a flight. For international flights of 12 hours or more, carriers must staff additional pilots beyond the standard two-person crew, establish rest periods and provide sleeping facilities on board for in-flight rest.
The FAA is updating its flying-time rules, and one proposal it is considering is to allow cockpit napping.
"We feel that cockpit napping is something that should be given serious consideration. It probably would be in the best interest of airline safety and might very well enhance it. How it's applied is up to (the FAA), but generally we favor it," Rayman said.
In testimony in June before a House transportation subcommittee, R. Curtis Graeber of the Flight Safety Foundation said "controlled rest on the flight deck should be made legal and used when necessary. ... The traveling public understands that all measures should be taken to ensure an alert flight crew during approach and landing, the most risky phase of flight."
Numerous foreign aviation authorities, as well as foreign carriers, have allowed such rest for 15 years, Graeber said.
Not everyone likes the idea.
"It's insane," said Kate Hanni, president of FlyersRights.org . "You need two sets of eyes watching at all times. If one pilot's sleeping, what if the other one falls asleep or has a heart attack?"