AIM 

4/20/23 

d.  Alcohol. 

1. 

Extensive research has provided a number of facts about the hazards of alcohol consumption and flying. 

As little as one ounce of liquor, one bottle of beer or four ounces of wine can impair flying skills, with the alcohol 

consumed in these drinks being detectable in the breath and blood for at least 3 hours. Even after the body 

completely destroys a moderate amount of alcohol, a pilot can still be severely impaired for many hours by 

hangover. There is simply no way of increasing the destruction of alcohol or alleviating a hangover. Alcohol also 

renders a pilot much more susceptible to disorientation and hypoxia. 

2. 

A consistently high alcohol related fatal aircraft accident rate serves to emphasize that alcohol and flying 

are a potentially lethal combination. The CFRs prohibit pilots from performing crewmember duties within 8 

hours after drinking any alcoholic beverage or while under the influence of alcohol. However, due to the slow 

destruction of alcohol, a pilot may still be under influence 8 hours after drinking a moderate amount of alcohol. 

Therefore, an excellent rule is to allow at least 12 to 24 hours between “bottle and throttle,” depending on the 

amount of alcoholic beverage consumed. 

e.  Fatigue. 

1. 

Fatigue continues to be one of the most treacherous hazards to flight safety, as it may not be apparent to 

a pilot until serious errors are made. Fatigue is best described as either acute (short-term) or chronic (long-term). 

2. 

A normal occurrence of everyday living, acute fatigue is the tiredness felt after long periods of physical 

and mental strain, including strenuous muscular effort, immobility, heavy mental workload, strong emotional 

pressure, monotony, and lack of sleep. Consequently, coordination and alertness, so vital to safe pilot 

performance, can be reduced. Acute fatigue is prevented by adequate rest and sleep, as well as by regular exercise 

and proper nutrition. 

3. 

Chronic fatigue occurs when there is not enough time for full recovery between episodes of acute fatigue. 

Performance continues to fall off, and judgment becomes impaired so that unwarranted risks may be taken. 

Recovery from chronic fatigue requires a prolonged period of rest. 

4. 

OBSTRUCTIVE SLEEP APNEA (OSA). OSA is now recognized as an important preventable factor 

identified in transportation accidents. OSA interrupts the normal restorative sleep necessary for normal 

functioning and is associated with chronic illnesses such as hypertension, heart attack, stroke, obesity, and 

diabetes. Symptoms include snoring, excessive daytime sleepiness, intermittent prolonged breathing pauses 

while sleeping, memory impairment and lack of concentration. There are many available treatments which can 

reverse the day time symptoms and reduce the chance of an accident. OSA can be easily treated. Most treatments 

are acceptable for medical certification upon demonstrating effective treatment. If you have any symptoms 

described above, or neck size over 17 inches in men or 16 inches in women, or a body mass index greater than 

30 you should be evaluated for sleep apnea by a sleep medicine specialist. 

(https://www.cdc.gov/healthyweight/assessing/bmi/adult_bmi/english_bmi_calculator/bmi_calculator.html) 

With treatment you can avoid or delay the onset of these chronic illnesses and prolong a quality life. 

f.  Stress. 

1. 

Stress from the pressures of everyday living can impair pilot performance, often in very subtle ways. 

Difficulties, particularly at work, can occupy thought processes enough to markedly decrease alertness. 

Distraction can so interfere with judgment that unwarranted risks are taken, such as flying into deteriorating 

weather conditions to keep on schedule. Stress and fatigue (see above) can be an extremely hazardous 

combination. 

2. 

Most pilots do not leave stress “on the ground.” Therefore, when more than usual difficulties are being 

experienced, a pilot should consider delaying flight until these difficulties are satisfactorily resolved. 

g.  Emotion. 

Certain emotionally upsetting events, including a serious argument, death of a family member, separation or 

divorce, loss of job, and financial catastrophe, can render a pilot unable to fly an aircraft safely. The emotions 

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Fitness for Flight