Crew Resources Management

Lecture 11-Sleep, Jetlag, Fatigue

SLEEP

Sleep What is it?

“The natural periodic suspension of

consciousness during which the powers of

the body are restored.”

3MedlinePlus Medical Dictionary

How much sleep do you really need?• Sleep requirements vary dramatically

among individuals (age and gender)• Newborns sleep as much as 20 hours/day• Children sleep 8-14 hours/day• Elderly sleep 6.5 hours/day

Factors affecting sleep quality• Comfortable condition (noisy rooms,

temperature, lighting)• Alcohol and caffeine consumptions• Time of sleep (too long or too short), this

will disrupt the normal sleep circadian rhythm & cycle.

• Circadian changes can affect sleep, especially when you are trying to sleep at times your body is not ready for sleep.

Circadian rhythms

• “Circadian rhythms” means 24 hours cycle in the biochemical and physiological process of humans.

• It also described as an internal biological clock that regulates our body functions, based on our wake/sleep cycle.

• Any time that our normal 25-hour circadian rhythm is interrupted, it will have physiological and behavioral impacts.

•

12 am 12 noon 12 am

3 - 5 am 3 - 5 pm

Performance level

+_

Human Performance• Generally, the lowest performance, alertness, and mood occur twice a day:

from 3 am to 5 am, and to a lesser extent, again from 3 pm to 5 pm. • During these time periods, errors are more likely to occur in judgment and

reaction time.

Importance of Sleep• Lack of adequate sleeps and rest results in

sleepy and fatigued pilots.• Air crash research revealed that the unsafe and

dangerous situations can result from a crew that has not had adequate sleep.

• This is because, not enough sleep lead to harder to pay attention, slower reaction times, poorer coordination & confusion.

• In other words, lose sleep or disrupt the body clock, will impair every aspect of human performance(Examples: Judgment and decision making can be degraded by 50 percent and memory can be degraded 20 percent by sleep loss)

Importance of Sleep• Pilot must know that sleep is important as the body

muscles and brain can only recover by sleep.• Beside that, sleep functions to rest mental & physical

condition with gather again the new energy.• The important is not the amount of the sleep but the

quality of sleep. • After 6 to 8 hours working, they need to restore back their

energy in about 7.5 hours of sleeping. • So that, they are thinking well and highly focus during their

work. • If they are not having enough sleep well, they can

cover it by take some napping.

Napping

• When sleep is not available or shortened by

operational concerns, combat naps are an alternative.

• Napping is a good strategy for coping with sleep deprivation during continuous operations or other times when it is difficult to get a good night’s sleep.

• Even naps as short as 10 min are good to prevent the individual feeling more tired.

JET LAG

JET LAG• Jet lag is a temporary disorder that causes

fatigue, insomnia, and other symptoms as a result of air travel across time zones.

• Jet Lag only occurs when flying from East-West or from West to East. In other words when we change time zones.

• Traveling from west to east shortens the day• Whereas from east to west travel lengthens the

day. • Jet Lag does not occur form North-South and vice

versa because there are no time zones changes.

Jet Lag

Jet lag is more evident if you fly from west to east because it is more difficult for your body to adjust to your “losing time”.

Why does jet lag occur?

• The cause of jet lag is the inability of the body of a traveler to immediately adjust to the time in a different zone.

• Thus, when a New Yorker arrives in Paris at midnight Paris time, his or her body continues to operate on New York time.

• As the body struggles to cope with the new schedule, temporary insomnia, fatigue, irritability, and an impaired ability to concentrate may set in.

• The changed bathroom schedule may cause constipation or diarrhea, and the brain may become confused and disoriented as it attempts to cope with schedules.

How jetlag can affect the pilots

• Jet lag causes circadian (body clock) changes conflict with the destination’s sunlight & activities.

• Due to that, a jet lag sufferer (pilot/crew/passengers) may experience poor sleep, fatigue, insomnia, headache, constipation, confusion, dehydration, and even memory loss.

• All these symptoms may reduce the pilot’s performance ( judgment, decision making)

• Thus, jetlag also directly will affect the flight safety.

Tips to Help MinimizeJet Lag• ➢ Adjust your bedtime by an hour a day a few days

before your trip to match the sleep schedule you will keep at your destination.

• ➢ Reset your watch to the destination time to help you adjust more quickly to your destination time zone.

• ➢ Drink plenty of water during your flight to avoid dehydration. Dehydration can make jet lag worse.

• ➢ Eat lightly but strategically. What you eat can have a direct influence on your wake/sleep cycle.

• ➢ Relax on the first day at your destination. give yourself a break and let your body adjust to the time change a little more gradually.

FATIGUE

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FATIGUEFATIGUE

“The state of feeling tired, weary, or sleepy that results

from periods of anxiety, exposure to harsh

environment, or loss of sleep.”

Fatigue

• Fatigue can be defines as extreme tiredness resulting from mental or

physical illness.

• Fatigue also is the bodies reaction to a physical or mental stress of a

prolonged duration.

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Fatigue and Accidents

• Fatigue is noted by aviation community for many years as having a strong impact on flight safety and efficiency.

• As length of fatigue increases, performance may decrease, consequently lead to aircraft mishaps.

1999

American Airlines Flight 1420

Flight delay, Arrival in the Little Rock area was around midnight. (two hours

after Capt.s normal bedtime).

1997Korean Airlines Flight 801

Pilot flown from Seoul to Australia, back to Seoul, to Hong Kong, and then back to Seoul again before his fateful trip to Guam,

all with only a few hours of rest

Overload,Stress & Fatigue

Flight AA 1420 landing crash at Little Rock, AR June 1, 1999

During their rush to land as soon as possible, both pilots became overloaded (stress & fatigue) with many important tasks. That led to errors . They failed to activate the automatic ground spoiler system . The pilots also failed to activate the auto braking system , to ensure the aircraft can stop on a wet runway.

Causes of Fatigue

• Lack of Restful Sleep• Works too hard • Dehydration• Caffeine• Overload• Stress• Jet Lag

Causes of Fatigue• Lack of restful Sleep

– It doesn’t matter how long or where the sleep is achieved, If sleep is not restful, fatigue is result.

– Duty sometimes cause pilot unable to allow sleep to take over, he becomes more fatigued

– lose sleep or disrupt the body clock, will impair every aspect of human performance

• Works too hard– Working hard makes body used up great deal of

Energy. One can expect to be more fatigued during a trip if they show up already tired from pushing their physical activities the day before.

Causes of Fatigue• Dehydration

– Dehydration means body lose a large amount of water.– Being dehydrated results in fatigue that might not be

noticed.

• Caffeine– Although considered a stimulated and used to stay

awake, ingesting too much caffeine keeps the body in a high degree of alertness, even to the point of being tense (unable to relax and sleep).

– Then, lead to fatigue

Effects Of Fatigue On Crew Performance

• Reaction Time Increases• take longer time for make decision making.

• Attention is Reduced– Overlook/Misplace Task Elements– Reduced Ability to Remain Task-Focused

• Memory is Diminished– Inaccurate Recall of Operational Events– Ex: quickly forgot command given by ATC.

Effects Of Fatigue On Crew Performance

• Overall Impairment– Poor and Careless Performance– Greater Tolerance for Error– Repetitive Conversation– Increased Incidence of Misinterpretation– Reduced Cooperation– Impairments in Crew Coordination– Increased Potential for Error in

Communication

Prevention of Fatigue

• Get restful and quality sleep– Maintain consistent schedules of sleep.– Control sleeping environment (Sleep in darkness,

Control noise, Control room temperature).– Napping

• Regular exercise– Maintaining good physical fitness with regular,

exercise will also help resist the effects of fatigue.

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Prevention of Fatigue

• Avoid dehydration– Drink enough water & reduce snacks

• Manage workload– Delegate Responsibility

• Avoid Stress– Avoid Prolonged or Intense Mental Activity

• Practice good nutrition

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Solutions for the Fatigue problemsFatigue in pilots can be reduced or

eliminated with simple and practical steps perform by:

1) FAA (Federal Aviation Administration)2) Airlines3) Individual Crew Members

Solutions for the Fatigue problems1) FAA (Federal Aviation Administration)

Laws.• FAA should enforce laws concerning the

conduct of airlines and pilots.• FAA should regulates certain activities

which may affect fatigue, such as alcohol , drug use and medical certification requirements.

FAA Regulation-Work Rules For Pilots• Pilots can fly up to eight hours a day.• A workday, which includes flight

preparation time on the ground, can extend up to 16 hours.

• Pilots can fly up to 100 hours per month on domestic flights.

[Source: FAA-Federal Aviation Administration]

FAA Regulation

• FAA should regulates certain activities which may affect fatigue

• Use acronym “DEATH”– Drugs– Exhaustion– Alcohol– Tobacco– Hypoglycemia

“DEATH”

• Drugs: Self Medication, Known side effects, Overdose risk

• Exhaustion: Lack of adequate sleep and rest, extreme environments

• Alcohol: Affects judgment, perception, coordination & communication.

• Tobacco: Affects night vision, Lung cancer• Hypoglycemia: Caused by lack of well-

balanced meals. Can lead to weakness, fainting, and decreased efficiency

Solutions for the Fatigue problems2) Airlines Role• The airline should reduce the chances of

errors due to fatigue by providing good management in terms of crew working hours and flight schedule.

• Flight should be delay during the bad weather.

Solutions for the Fatigue problems3) Individual Crew Members• It is in their hands to take the necessary steps to remain safe and

alert. • Planning to get enough sleep before a trip is the most obvious step. • Another step would be to eat properly and had an exercise. This

will make the pilot healthier and more alert. • They must drinking plenty of water, especially during a flight, and

avoid coffee, sodas and alcohol. • They can wear noise-reducing headsets if the cockpit is loud. They

must stay home when they are ill, for their own sake and for their fellow crew members.

• Crew (pilot) should cancel the take-off or landing during the bad weather

Conclusion

• Aircrews and leadership should be well educated about the dangers of fatigue so they can conduct accurate pre-mission risk assessments and counter any identified risks.

• The best fatigue countermeasures are to ensure that everyone gets enough sleep on a daily basis and to keep shift work to a minimum.