The human body requires sleep to retain its functionality, preserve alertness, and encode memory; however, obtaining required sleep over long-term missions can be difficult. Flight crews may be aware of the risks of fatigue, but will ignore them to continue their course or reduce cost of operations. Future flight operations might increase the risk of increased fatigue of flight crews. This may result from:
• ultra long range flights with minimum crew
• harmonized European legislation allowing longer flight duty times
• increased regional operations
• increased pressure on crews to improve economics
• passenger and crew screening requirements
Sleep deficits of as little as 2 hours a night can stockpile and lead to drastically reduced awareness. While the only way to truly reverse this damage is through a prolonged period of rest, other fatigue management strategies have been proposed, including off-duty rest periods integrated into the pilot’s schedule. Businesses are opposed to the change for reasons of cost, but pilots are pushing for more stringent rules on the matter to ensure safety.
It is essential that all flight crewmembers remain alert and contribute to flight safety by their actions, observations and communications.
- Impaired performance: delayed, erroneous or chaotic responses to normal stimuli
- Reduced ability for the human pilot to process complex information and cope with the unexpected. It is when the automation fails or evidences unexpected behavior that the human needs to step in. Fatigue dramatically compromises the ability of the flight crew to perform as needed in off-nominal conditions.
- Automation mode confusion.
- Reduced alertness
- Adverse physiological consequences: stressors affecting alertness
- Adverse effects of long commutes on flight crew performance
- Reversions to “fight-or-flight,” panic or freeze instinctive self-preservation behaviors in emergency situations; reflexive response to stimulation
- Failure to report errors and omissions arising from fatigue that do not necessarily result in reportable incidents
- Poor environmental characteristics of crew rest areas in aircraft
- A recent FAA Office of Inspector General report found that pilots might not be reporting all instances of fatigue. The report noted that, of 33 air carrier pilots interviewed by OIG researchers, 26 (79 percent) said that, at some time, they had been fatigued while on duty; nevertheless, only eight pilots notified their air carrier of their condition. Among the reasons cited for not reporting fatigue was the fear of “punitive action from their employers.”
Corroborating sources and comments
http://dodreports.com/ada428355 NTSB Most Wanted item: Address Human Fatigue
The new maximum flight duty regulations impose a hardship on crewing numbers for operators. First of all, it means operators will have to recruit additional pilots at a time when regulations impose stiffer entry level qualifications for Part 121 flight crew, and at time when retirements are about to increase. The interesting thing in all of this, the number of airlines looking for new hires all at the same time in numbers we haven’t seen before. A good idea at a time when it may be more difficult to implement than we care to admit.
In the US, flight duty time limits can be traced back to the days of early air-mail flight schedules. These antiquated rules are being re-evaluated.
http://aviationweek.com/business-aviation/preventing-crew-fatigue-zzz (Piece written in 2015 about aviation fatigue. The human body requires sleep to retain its functionality, preserve alertness, and encode memory. Sleep deficits of as little as 2 hours a night can stockpile and lead to drastically reduced awareness. NTSB is looking for ways to combat the issue.)
https://www.bna.com/naps-flight-crew-n57982085964/ (A proposed 2017 policy by Transport Canada pushes fatigue management rules, active countermeasures and risk management, and off-duty rest periods integrated into the pilot’s schedule. Businesses are opposed to the change for reasons of cost, but pilots are pushing for more stringent rules on the matter. Regulations to be finalized by late fall.)
https://www.nbaa.org/ops/safety/fatigue/the-alert-crew-fatigue-awareness-in-flight-operations.pdf (Best practices outline for countermeasuring fatigue. Details corroborate those in other documents. Note in particular that the NBAA claims to have been advising these practices to airlines for “years”.)