Chris & Daniel FATIGUE, BODY RHYTHMS & SLEEP JET LAG JET LAG The expression 'jet lag' is established in the English language as the description applied to the lack of well- being experienced after long- distance air travel. Most travelers take some days to recover from a long flight & during this time their performance, motivation, mood, & behavior may suffer to some degree. Amongst crew members the possibility that one or more of them can occasionally drop of to sleep on long range night flights has long been known. Cases have been revealed where all the flight deck have been asleep at the same time. JET LAG & FLIGHT CREW There are evidence of slow reaction & decision making times, defective memory for recent events, errors in computations &, a tendency to accept lower standards of operational flying. FATIGUE FATIGUE The definition of fatigue is a source of difficulty which has tended to generate confusion & retard progress. INTERPRETATIONS OF FATIGUE Fatigue may reflect inadequate rest
Refer to symptoms associated with disturbed or displaced rest (Jet lag).
May be interpreted as excessive muscular or physical activity.
Can result when minimal physical activity has occurred. RESEARCH BY NASA Survey in the USA, 93% of the pilots responding reported that fatigue was a problem & 85% said they felt extremely tired or washed out during the previous 30 days'.
In a analysis of data obtained in the USA from the confidential ASRS program, NASA reported in 1981 that fatigue-associated decrements (in performance) resulted in substantive potentially unsafe aviation conditions. FATIGUE BODY RYTHMS A daily cycle of biological activity based on a 24-hour period & influenced by regular variations in the environment, such as the alternation of night and day. CIRCADIAN DISTURBANCE OF BIOLOGICAL RHYTHMS A disturbed pattern of biological rhythms is now the foundation upon which the life of the long-range flight crew member is based.
When the pattern of one's living environment changes, as occurs in shift work or irregular working schedules or when traveling across time zones, the rhythm of all the cyclic systems in the body must re adapt to the new environment. SLEEP Sleep has been divide into two basic kinds, orthodox & paradoxical. SLEEP HUMAN PERFORMANCE & SLEEP It is generally thought that the main problem facing crew members is that of disturbance but it is clear that loss of sleep can accumulate on long flights.
Even small periods of sleep deprivation have been shown to affect performance.
The performance decrement resulting from sleep deprivation increases with altitude & is further increased with higher workload.