Falling asleep on the job usually brings down the employer's wrath, but for pilots it's an actionable offense.

And go! Airlines did take action, dismissing the two pilots who fell asleep during a Honolulu-Hilo flight in February.

In this case, the FAA asserts, there was no evidence that go! had skirted any regulation; each of its pilots had been given more than the required hours of rest before the flight.

Even so, this incident, as well as another airline's accident involving pilot fatigue last year in Michigan, suggests that a broader review of rules on pilot fatigue is in order.

That is, in fact, what the National Transportation Safety Board has recommended to the Federal Aviation Administration. Updated regulations governing the length of pilots' flight shifts and how much rest time they need has been on the NTSB "most-wanted list" for many years. The rules have not been revised since 1995.

The FAA imposes an eight-hour limit for a pilot's flight time during a 24-hour period, provided the pilot has had at least eight continuous hours of rest during that period.

If a pilot's actual rest is less than nine hours in the 24-hour period, extra rest time must be given in the next period to compensate. The rules do not govern how long pilots can be on duty — "standby time."

Safety board officials cite research showing accidents increasing sharply after a duty period of about 10 to 12 hours.

A review of the rules may indeed point to a need for shortening the span in which a pilot can be in the air.

The FAA has argued in the past that the current regulations are sufficient but rightly has pledged to take the board's recommendation seriously. Its officials point out that regulations can only do so much to ensure that a pilot feeling tired will call in for a day off. And many pilots — including the go! pilot diagnosed with sleep apnea only after the incident — may be unaware how cumulative fatigue affects them.

The agency itself plans a symposium next week on managing aviation fatigue, involving representatives from air carriers, unions, aviation associations and scientists. Some airlines already include fatigue management in pilot training programs.

That's good, but the FAA needs to consider making such training mandatory as part of its regulatory review.

The Air Line Pilots Association also advocates for rules to restrict duties given to crews immediately before a flight.

That's one example of a reasonable step to take toward heightening pilots' ability to perform their jobs safely.