The introduction of ultra long distance commercial transports that can fly over 16 hours nonstop, such as the Airbus 380 and Boeing 777, has created additional conflict between airline pilots and their employers, with the Federal Aviation Administration (FAA) late last year setting basic rules for such time travel.

As the FAA attempts to determine exactly how much sleep flight deck crews need, fatigue has become a growing concern as pilots work longer hours and National Transportation Safety Board (NTSB) investigations show that fatigue has played a key role in some recent aviation accidents.

Seven U.S. airlines (American Airlines, Atlas Air, Continental Airlines, Evergreen International, JetBlue Airways, United Airlines and US Airways) late last year sued the FAA in federal court, claiming the U.S. aviation agency broke its own rules when it set new enhanced standards for pilot rest times last October without input from the carriers.

The companies said they should have had a chance to comment on the new pilot fatigue rules that would entail “substantial financial burdens and costs” on them.

"The FAA has neither demonstrated how the rule will advance safety, considered the potential that the rule may actually diminish safety, nor justified the significant costs of the rule against any purported benefit. Because the agency bypassed the rulemaking process, it has deprived stakeholders with expertise on the underlying safety issues the opportunity to participate in a public comment process,” the carriers added. The order was “legally defective” and “not produced in a way that is reasonably calculated to promote safety,” they added.

Delta Air Lines, which recently merged with Northwest Airlines, was not a party to the lawsuit. In 2006, the FAA and Delta signed an agreement authorizing Delta pilots to fly 16-17 hour flights between the U.S. and India. The deal included extended rest periods for cockpit crews departing the U.S. and two full days off in India prior to the return leg.

The FAA said the new crew rest deal would be the model for FAA rules regarding ultra long flights. And pilot unions saw the Delta deal as an important precedent, contending that such measures are necessary to maintain safety margins.

Last October, the FAA issued an operations bulletin for all ultra long-range flights that doubled the amount of time pilots must rest at their overseas destination, from 24 to 48 hours, prompting the lawsuit in December.

A successful legal challenge would force the FAA to undertake a standard rulemaking process that could take years, delaying establishment of more stringent rest requirements.

Delta has criticized the airlines’ lawsuit, saying a successful legal challenge could affect Delta’s “ability to sustain safe and economically viable operations” on ultra-long flights. It believes that allowing less-costly crew rest rules for rival air carriers would put Delta at a competitive disadvantage.

Meanwhile, the FAA has started to gather scientific data on how to handle fatigue.

In June 2008, it held an aviation fatigue management symposium, the first event sponsored by the U.S. aviation agency that focused specifically on managing fatigue in all aspects of aviation, whether suffered aboard aircraft, in the hanger on the flight line, or in air traffic control facilities.

The three main symposium objectives were to: provide the most current information on fatigue physiology, management, and mitigation alternatives; develop a common understanding of fatigue issues and identify challenges; and, forge collaborative alliances to initiate actionable mitigation strategies.

Attendees included representatives of domestic and foreign air carriers, aviation associations, aircraft manufacturers, academia and government air safety organizations. But the symposium was closed to the public and media despite increased interest in the subject.

The NTSB urges the FAA to take steps to manage pilot fatigue, which the Safety Board cited as factors in two non-fatal regional jet mishaps in 2007 and one incident early last year.

The NTSB said a regional jet overran the end of a runway in Michigan in 2007because the pilots elected to land on a snowy runway without performing the required landing distance calculations.

The mishap occurred on April 12 when a Bombardier/Canadair Regional Jet (CRJ) CL600-2B19 operated as Pinnacle Airlines 4712 ran off the departure end of Runway 28 after landing at Cherry Capital Airport (TVC) Traverse City, MI. There were no injuries among the 49 passengers and three crewmembers.

The probable cause determination cited the pilots' decision to land without performing a landing distance assessment, which was required by company policy because of runway contamination reported by ground operations personnel

The Safety Board said “this poor decision-making likely reflected the effects of fatigue produced by a long, demanding duty day, and, for the captain, the duties associated with check airman functions.” Had the pilots made the required calculations, using current weather information, the results would have shown that the runway length was inadequate for the contaminated runway conditions described.

In February 2008, a go! regional jet flight from Honolulu to Hilo, Hawaii, overshot its destination. Controllers repeatedly attempted to contact the crew for over 18 minutes as it strayed off course. The passenger jet traveled 26 nautical miles beyond its intended destination before the flight crew responded to a controller’s frantic calls. NTSB investigators said the two go! pilots, who were fired, had unintentionally fallen asleep.

The NTSB determined that the probable cause of a Shuttle America Embraer ERJ- 170 accident in early 2008 in Cleveland was the failure of the flight crew to execute a missed approach when visual cues for the runway were not distinct and identifiable.

In its final report on the accident investigation, the Safety Board noted that the captain's fatigue, which affected his ability to effectively plan for and monitor the approach and landing, contributed to the accident.

As a result of the aforementioned accidents/incidents, the Safety Board made two recommendations to the FAA addressing human fatigue within airline operations.

The Safety Board advised the FAA to develop guidance, based on empirical and scientific evidence, for operators to establish fatigue management systems, including information about the content and implementation of these systems.

The Board also drafted an advisement for the U.S. aviation agency to develop and use methodology that will continually assess the effectiveness of fatigue management systems implemented by operators, including their ability to improve sleep and alertness, mitigate performance errors, and prevent incidents and accidents.

The FAA aviation fatigue symposium included remarks by then Acting FAA Administrator Robert Sturgell.

Sturgell said: “I think we all acknowledge that even with an outstanding safety record, we’re not where we need to be when it comes to understanding and dealing with fatigue. This meeting aims to put us on a level playing field with what we know, with what we understand.

“At this conference, I want to look at new ways to manage fatigue for all personnel in this industry, the most current information on fatigue physiology, management and mitigation alternatives. I encourage you to leave your day job at the door. Think outside the box. Specifically, black ones.

“As we move forward, we need to define what is an acceptable level of fatigue risk and what levels of fatigue must be minimized. We need to come to agreement on what studies or data would be needed to provide those definitions.

“I’m not talking necessarily about adopting prescriptive criteria for fatigue risk abatement. All options will be considered. I think we need to address all levels of fatigue and put appropriate mitigations in place — mitigations that are proportionate to the risk.

“We’re trying to do something innovative here with a topic that generates a lot of emotion and anecdotal claims. My hope is that the conversations we’re about to have will bring some clarity to the issue and help us decide where to go using a data-driven approach.

“This isn’t a venue for arguments about economics, and it’s not about contract negotiations. But it is a chance for us to give a boost to safety where one is needed,” Sturgell stated.

NTSB experts discussed operational factors contributing to fatigue during flight operations and in the air traffic control towers. Other sessions looked at the effects of fatigue on long-haul flights and fatigue issues related to shift work. The three-day session concluded with a group discussion on future fatigue mitigation initiatives.

The FAA recently released the proceedings of the aviation fatigue management symposium.

The proceedings includes a wealth of information on the subject, including a presentation by the University of South Australia’s Matthew Thomas who presented a paper on the effects of fatigue on threat and error management behavior of long-haul fight crew.

According to Dr. Thomas, fatigue is associated with many forms of performance degradation, and laboratory studies have demonstrated impairment on performance measures such as vigilance, reaction time, and short-term memory.

“While the results of these studies are then typically generalized to real world behavior, the extent to which the outcomes of these experiments reflect the effects of fatigue on the performance of actual work tasks is not known. Specifically, relatively little is known about the effects of fatigue on the operational performance of a crew, within the complex domain of long-haul flight operations,” said Thomas.

The study investigated the effects of fatigue on the operational performance of international long-haul flight crew. A total of 67 crew participated in the study after either completing a long-haul flight pattern (non-rested), or after having at least four consecutive days free of duty (rested).

The study utilized trained expert observers to analyze and evaluate crews’ threat and error management behaviors and decision-making performance during a simulated flight operation. The simulator scenario was designed to present crews with a “normal” flight operation, which included a series of operational threats designed to provide additional workload for the crews, yet not extend outside the parameters of normal flight operations.

The results of this study highlight the effect of fatigue, both in terms of the “fatigue-proofing” strategies used by crew to protect performance, and also the negative impacts of fatigue on operational performance.

The results of the study highlighted the impacts of fatigue on decision-making performance, and also the shifts in error profile and error management behaviors observed to be associated with fatigue.

The study examined the fatigue-related changes in threat and error management, and decision-making behavior of long haul flight crew.

The research shows that relatively little is known about the subtle effects of fatigue on the performance of flight crew during normal long haul flight operations.