Managing pilot's fatigue
Here's a little summary on fatigue in aviation. I will focus more on methods of dealing with fatigue in aviation rather than causation.
Fatigue is aviation has often been underappreciated. Particularly in commercial and military aviation, fatigue was often seen as 'part of the package' of being a pilot and that the aviation society had to accept and acknowledge fatigue as a by-product. However, after a DC-8 Mishap in Guantanamo Bay that was officially attributed to flight crew fatigue, NTSB (National Transport Safety Board) started shifting focus towards understanding the cause and effect of pilot fatigue.
NTSB study of major domestic air carriers accidents from 1978 to 1990 estimated that 4-7% civil aviation cases were attributed to fatigue.
Fatigue is a well recognized operational hazard for pilots and we clearly need to curb such a hazard to a bare minimum.
It is a universal fact that the surest way to fight fatigue would be sleep. This in my opinion is only partially true. What is key is GOOD SLEEPING HABITS. These habits should focus on hygiene, isolation and simple 'rituals'. For example,
- Keep the sleeping area clean, cool, quiet and very dark (use earplugs or sleep masks)
- Have a simple ritual such as reading, warm baths, flossing and brushing teeth before hitting the sack. They are very subtle cues that prepare your mind for its well deserved rest.
- Studies have also show that 3-4hrs prior to sleep, engaging in aerobic exercise can improve sleep quality.
- Avoid caffeine, nicotine and alcohol as they not only prolong the transition period between consciousness and the first stage of sleep, but also reduce REM (rapid eye movement) sleep which is actually the most restorative type of sleep.
Proper work rest management is also essential. For a full day of 24 hrs, we must ensure we get at least 10hrs off (8 hrs of which should be spent asleep).
This can actually be done with FAST Fatigue Analysis Scheduling Tool (which i have sort of made a short summary of in the Ab-initio Fatigue related incident section). FAST is actually a computerized scheduling tool that can help periods when fatigue counter measures are needed the most and also plan best time to sleep a variety of situations. FAST is a Windows program that allows people who plan and schedule sorties quantify the effects of different schedules on human performance. It gives a easy to read graphic output that allows these planners to wisely select the right balance between operational schedules and optimum pilot performance.
However, there are pharmacological methods to fight fatigue. The most common and socially accepted chemical would of course be caffeine.
Caffeine is an alertness enhancing substance that works only for periods of short continuous wakefulness (37 hrs) rather than longer periods (60 or more hrs). also there are other alertness enhancing drugs which include modafinil and amphetamines that have proven to give up to 50 plus hours of sustained pilot performance. It has been proven that chronic use of such synthetic substances will cause cognitive processing to deteriorate but when taken in moderation can be rather effective. These substances are are still used in small amounts by pilots in the US Air Force.
In conclusion, fatigue will always be a problem in aviation operations and suggestions such as those listed above can only curb or minimise lapses of fatigue that will affect pilot judgment. The most effective channel would of course to have proper fatigue management structure in place and have quick restorative procedures in place to battle the 'wear and tear' of piloting.
Here's a short insight into a practical and highly effective method of countering fatigue in aviation called 'Autogenic Training'.
Autogenic training has been scientifically proven to be an effective and efficient counter to fatigue. German physician, Johannes Schultz, developed a method to achieve what he described as simply ‘deep relaxation’ and the magnitude of its restorative ability is as refreshing as a good night’s sleep.
Autogenic training is based on a combination of hypnosis and yoga and it involves relaxing the mind using repetitive phrases, and upright posture and controlled breathing (Welz, 1991). Autogenic training is inexpensive and can be administered quickly (as fast as 10mins!), requiring no equipment or assistance. Extensive research on the effects of autogenic training in aviation has been carried out by NASA on a group of military pilots using a ‘rotating chair technique’. NASA assessed motion sickness tolerance by calculating the number of cumulative rotations that research participants were able to achieve in the rotating chair prior to reaching their major malaise endpoint. The motion sickness symptoms were rated using a standard diagnostic scale. Then physiological data from one pilot was obtained during a training flight in an F–18 aircraft after completion of his autogenic training. Results demonstrated a significant increase in tolerance to laboratory-induced motion sickness tests and a reduction in autonomic nervous system response levels following autogenic training (Casey & Hufangel, 2005). This psycho-physiological relaxation technique allows pilots experiencing fatigue to regenerate their energy and focus within a very short time frame. This is particularly useful for pilots on long haul flights as well as pilots whom have repetitive flights (adventure and agricultural flights) to quickly recuperate before the next shift or operation. I strongly recommend not only reading but also trying out the practical parts of this article that explains how autogenic training works and the basic 6 steps to achieve deep relaxation.
Welz, K.H., Autogenic Training: A Practical Guide in Six Steps, HSCTI, Page 2-3, 1991
Casey, C. & Hufangel, J., Autogenic Feedback Training Exercise: A Treatment for Airsickness in Military Pilots, Education Associates Program NASA Ames Research Centre, The International Journal of Aviation Psychology, Issue 15(4), Page 395–412, January 2005