Charles Lindbergh described the destructive impact of fatigue in aviation back in 1953 after his historic solo transoceanic flight. But he wasn't the first to identify fatigue as a major risk factor for aviation accidents. The Civil Aeronautics Act of 1938 addressed the issue of flight times and duty hours.

Although aviation boasts a fairly remarkable safety record, fatigue is still a problem because it contributes to diminished concentration, decreased reaction time, and a poorer ability for sound decision-making. This increases the chances of unfortunate incidents that could've been avoided with proactive measures.

Cabin and flight crew members must follow the Federal Aviation Administration's obliged crew rest rules spelled out by part 121. Before discussing preventive strategies to avoid aviation fatigue, our instructors want you to learn about some common causes and effects of fatigue.

Cause #1- Sleep Loss

Although the optimal sleep duration per night varies among individuals, an average of eight hours of sleep is recommended for adults. Restricted sleep was associated with confusion and errors in a study conducted in a Boeing 747-400 simulator. So chronic trimming or sleep deprivation of sleep, whether acute or restrictive, can lead to a progressive reduction in performance, which can intensify when sleep restriction per night increases.

Cause #2- Extended Wakefulness

The desire for sleep is linked with wakefulness length. It's because of a homeostatic process where an increase in awake time follows an intensification in sleep pressure. It leads to sleepiness when the pressure for a nap rises above a particular threshold.

Studies show aircrews with a lengthier time since they woke up made 42% more mistakes than those with a shorter time since awakening. Most such errors were found to be errors of omission, but the crew also made more tactical decisions and procedural errors.

Cause #3- Circadian Phase

Our body clock or circadian rhythm refers to the neural pacemaker that monitors a night-day cycle through ophthalmic light input to determine the predilection for sleeping at night. It controls the circadian process and sets the threshold for sleep pressure.

Sleepiness is at its peak, with lower levels of alertness in certain windows of the circadian. Working at odd times can disrupt wake-sleep patterns like time-zone transitions, causing jet lag. This may have a greater impact on cockpit performance.

Cause #4- Workload

According to the ICAO, workload refers to mental and physical activities. It identifies three main facets of workload: time constraints, the amount and nature of work, and factors associated with the performance capacities of individuals.

Interestingly, both low and high-workload situations can impact the capacity of fatigued individuals because of high mental demand or lack of sufficient mental stimulation. A low workload can lead to lower task engagement and motivation. Meanwhile, a high workload can result in sleep impairment or distress, increasing the need to wind down.

The Impact of Fatigue

Unintentional sleepiness can cause pilots to experience in-flight fatigue. It can lead to lower levels of alertness during brief overpowering periods of sleep, leading to performance decrements.

Studies show in-flight performances dip significantly after 24 hours of wakefulness. A survey revealed over 80% of pilots reported that fatigue has affected their flight performance.

A further 87% admitted mistakes being made when they felt fatigued because it lowers situational awareness, increases distractibility, apathy, and forgetfulness, and slows down reaction time.

Heightened emotional activity was also reported by pilots during long-haul flights, which further leads to impaired cognitive processing. Moreover, fatigue also leads to considerable visual perceptual impairment and neglect.

How to Avoid Aviation Fatigue Problems

Scheduling

Known as Decision 83, the maximum flight time allowance per month was set to be 85 flight hours by the FTL in 1934. However, the scheduling and number of flight hours are both critical aspects of managing the risks of fatigue. Currently, FAA regulations state that the maximum daily FDP duration depends on the number and start time of scheduled flights per flight duty period.

Sleep Hygiene

Although good quality and sufficient sleep is the best way to prevent fatigue, poor sleep hygiene can cause sleep difficulties in otherwise healthy people.

Circadian disruption, irregular flight schedules, time zone, weather changes, and other reasons can make it difficult for the crew members to maintain proper sleep hygiene.

Sleep hygiene training helps improve sleep quantity and performance, which is why it's currently regarded as one of the most important aspects of FM.

Pre-Flight Nap

Since longer periods of wakefulness lead to more sleep pressure and fatigue, well-rested pilots with a synced sleep-wake cycle can stay alert and perform optimally. Pre-shift naps can therefore help increase performance and decrease fatigue.

A sleep inertia recovery period is also equally important after the nap, regardless of the length. Caffeine is known to be helpful in reducing the impact of sleep inertia in the same way as temperature, sound, and light, but this is currently under research.

Fatigue Detection Technologies

Many tools are now available to increase the effectiveness of the overall safety management approaches. Eye metrics, speech analysis, and electrocardiography are two major technologies that seem promising in detecting sleepiness or fatigue.

Besides fatigue, panic and low confidence can also impact performance in the skies. Familiarizing yourself with all systems and procedures beforehand can set you up for success when you start your journey of becoming a first officer in a regional airline.

If you want to learn in an encouraging environment, we welcome you to join our 1-day, 3-day, and 5-day best flight simulator for pilot training programs designed to help pilots feel ready to navigate diverse flight situations confidently.

Speak to an experienced instructor to learn more about crj200 flight simulator programs tailored according to the needs of particular regional airline companies to help aspiring pilots flourish as they take a step toward their new careers.