FATIGUE IN
AVIATION
FATIGUE IN
AVIATION
Prepared by
Aerospace Medical Education Division,
AAM-400
To obtain copies of this brochure online:
http://www.faa.gov/pilots/safety/pilotsafetybrochures/
or contact:
Federal Aviation Administration
Civil Aerospace Medical Institute
AAM-400
P .O. Box 25082
Oklahoma City, OK 73125
(405) 954-4831
OK-20-0925 04-29-2020
LIFESTYLE RECOMMENDATIONS
Don’t…
• Consume alcohol or caffeine 3-4 hours before
going to bed.
• Eat a heavy meal just before bedtime.
• Take work to bed.
• Exercise 2-3 hours before bedtime. While
working out promotes a healthy lifestyle, it
shouldn’t be done too close to bedtime.
• Use sleeping pills (prescription or otherwise).
Do…
• Be mindful of the side effects of certain
medications, even over-the-counter
medications – drowsiness or impaired
alertness is a concern.
• Consult a physician to diagnose and treat any
medical conditions causing sleep problems.
• Create a comfortable sleep environment at
home. Adjust heating and cooling as needed.
Get a comfortable mattress.
• When traveling, select hotels that provide a
comfortable environment.
• Get into the habit of sleeping eight hours
per night. When needed, and if possible,
nap during the day, but limit the nap to less
than 30 minutes. Longer naps produce sleep
inertia, which is counterproductive.
• Try to turn in at the same time each day. This
establishes a routine and helps you fall asleep
quicker.
• If you can’t fall asleep within 30 minutes of
going to bed, get up and try an activity that
helps induce sleep (watch non-violent TV,
read, listen to relaxing music, etc).
• Get plenty of rest and minimize stress before
a flight. If problems preclude a good night’s
sleep, rethink the flight and postpone it
accordingly.
Fatigue is an expected and ubiquitous aspect of life.
For the average individual, fatigue presents a minor
inconvenience, resolved with a nap or by stopping
whatever activity that brought it on. Typically, there are
no significant consequences. However, if that person is
involved in safety-related activities such as operating a
motor vehicle, piloting an aircraft, performing surgery,
or running a nuclear reactor, the consequences of
fatigue can be disastrous.
DEFINITION
Defining fatigue in humans is extremely difficult due
to the large variability of causes. Causes of fatigue can
range from boredom to circadian rhythm disruption
to heavy physical exertion. In lay terms, fatigue can
simply be defined as weariness. However, from an
operational standpoint a more accurate definition might
be: “Fatigue is a condition characterized by increased
discomfort with lessened capacity for work, reduced
efficiency of accomplishment, loss of power or capacity
to respond to stimulation, and is usually accompanied
by a feeling of weariness and tiredness.”
TWO KEY CONCEPTS CAN BE DERIVED
FROM THIS SECOND DEFINITION
1. Fatigue can develop from a variety of sources.
The important factor is not what causes the
fatigue but rather the negative impact fatigue
has on a person’s ability to perform tasks. A long
day of mental stimulation such as studying for an
examination or processing data for a report can
be as fatiguing as manual labor. They may feel
different—a sore body instead of a headache and
bleary eyes—but the end effect is the same, an
inability to function normally.
2. Fatigue leads to a decrease in your ability to carry
out tasks. Several studies have demonstrated
significant impairment in a person’s ability to
carry out tasks that require manual dexterity,
concentration, and higher-order intellectual
processing. Fatigue may happen acutely, which is
to say in a relatively short time (hours) after some
significant physical or mental activity.
Or, it may occur gradually over several days or weeks.
ypically, this situation occurs with someone who does
not get sufficient sleep over a prolonged period of time
(as with sleep apnea, jet lag, or shift work) or someone
who is involved in ongoing physical or mental activity
with insufficient rest.
STRESSORS
General aviation pilots are typically not exposed to
the same occupational stresses as commercial pilots
(i.e., long duty days, circadian disruptions from night
flying or time zone changes, or scheduling changes).
Nevertheless, they will still develop fatigue from a variety
of other causes.
Given the single-pilot operation and
relatively higher workload, they would be just as much
at risk (possibly even more) to be involved in an accident
than a commercial crew. Any fatigued person will exhibit
the same problems: sleepiness, difficulty concentrating,
apathy, feeling of isolation, annoyance, increased
reaction time to stimulus, slowing of higher-level mental
functioning, decreased vigilance, memory problems, task
fixation, and increased errors while performing tasks.
None of these are good things to have happen to a
pilot, much less if there is no one else in the aircraft to
help out.
In a variety of studies, fatigued individuals consistently
underreported how tired they really were, as
measured by physiologic parameters. A tired individual
truly does not realize the extent of actual impairment.
No degree of experience, motivation, medication,
coffee, or will power can overcome fatigue.
ANTIDOTE TO FATIGUE
Obtaining adequate sleep is the best way to prevent
or resolve fatigue. Sleep provides the body with a
period of rest and recuperation. Insufficient sleep
will result in significant physical and psychological
problems. On average, a healthy adult does best with
eight hours of uninterrupted sleep, but significant
personal variations occur. For example, increasing
sleep difficulties occur as we age, with significant
shortening of nighttime sleep. A variety of medical
conditions can influence the quality and duration
of sleep. To name a few: sleep apnea, restless leg
syndrome, certain medications, depression, stress,
insomnia, and chronic pain. Some of the more
common social or behavioral issues are: late-night
activities, excessive alcohol or caffeine use, travel,
interpersonal strife, uncomfortable or unfamiliar
surroundings, and shift work.
PREVENTION
No one is immune from fatigue. Yet, in our society,
establishing widespread preventive measures
to combat fatigue is often a very difficult goal to
achieve. Individuals, as well as organizations, often
ignore the problem until an accident occurs. Even
then, implementing lasting change is not guaranteed.
Lifestyle changes are not easy for individuals,
particularly if that person isn’t in complete control
of the condition. For example, commercial pilots
must contend with shift work and circadian rhythm
disruption. Often, they also choose to commute long
distances to work, so that by the time a work cycle
starts they have already traveled for several hours.
While a general aviation pilot may not have to deal
with this, a busy lifestyle or other issues may lead to
fatigue. Therefore, general aviation pilots must make
every effort to modify personal lifestyle factors that
cause fatigue.