CIRCADIAN RHYTHM AND ITS EFFECTS ON AIRCREW

CIRCADIAN RHYTHM AND ITS EFFECTS ON AIRCREWS

Introduction

By definition, the circadian rhythm is the biological clock within humans that controls the human body’s functions. It is dependent on one’s sleep cycle. On the other hand, circadian rhythm disruption occurs when there are changes in one’s sleep cycle. This can also be referred to as jetlag (Caldwell, 2005).

Generally, many people are in the position of suffering jetlag since anyone can be a traveler. Mostly, jetlag is faced by travelers most of the time. It could be from long flights that could disrupt one’s normal sleep cycle to even those traveling by road or air. In the aviation sector, crew members may suffer from jetlag, mostly due to their work nature. They may be required to travel at different and odd times as their work is, and this definitely makes them not have a specific sleep schedule. Thus, jetlag is a common issue among crew members in the aviation industry.

How jetlag and circadian rhythm disruption affects human safety

Now that jetlag is familiar; we look at how it affects human safety in the aviation sector, to be specific. Jetlag affects human beings in various ways. Examples include the following:

• General body fatigue
• Difficulties in sleeping which could lead to insomnia
• Mood changes due to changes in the hormonal levels
• Pregnant crew members are in a position to miscarry in their first trimester during pregnancy due to jetlag.
• Headaches
• Stomach upset
• Intestinal problems
• And other health-related issues.

It is said that a human being can take up to 1 to 2 weeks to recover from jetlag issues that arise from one flight. However, it is difficult for crew members to heal since their job is continuous, and they get to travel quite regularly. Thus, they are prone to suffering from serious jetlag issues, resulting in chronic diseases (Caldwell, 2005).

Apart from the health issue mentioned above, jetlag is also mentioned to cause reproductive health issues mostly for the female crew members. The World Health Organization (WHO) also mentions that jetlag can cause cancer, too, when people get to work or be awake during normal sleeping hours. Also, it should be observed that not everyone faces jetlag similarly as everyone’s body is different. Thus, some crew members may get to face it more compared to others.

One thing to note is that all this is mostly brought about by the different time zones across the world. When crew members get to travel from one place to another, they may be moving from a place that is in the nighttime when they are supposed to be asleep to a place where it is already day (Caldwell, 2005). Thus, it gets difficult for them to get sleep easily, and they end up having little sleep. This definitely gets to cause circadian rhythm disruption as their sleep cycle is affected.

All the above explanations and points get to explain how jetlag affects human safety in general and in the aviation sector. If the crew members do not learn about this and know how to maintain it, it may also affect the passengers on board the planes. If the pilot has sleep issues and jetlag, they may not be in their best position to work or anything that could happen during the flight, which could endanger the lives of all those on board. Some accidents have happened historically due to issues resulting from jetlag, as explained in the next section. Thus, it is necessary to examine this issue with keenness.

Accidents that have occurred due to jetlag

• The 808 Kalitta International Flight

This accident occurred in the year 1993 in Guantanamo Bay, where three crew members died. According to the National Transportation Safety Board (NTSB), this accident occurred during landing due to fatigue from sleep-related issues, which caused impaired judgment. The plane was moving from Norfolk in Virginia to Guantanamo bay, and it was carrying mails and food substances to the navy base in Guantanamo Bay.

• The 801 Korean flight

This crash was also caused by different failures which included the captain being fatigue and the crew’s inefficient training, among others. The crash killed 228 people on board among the 254 occupants that were in the plane. The accident is said to have happened near Guam in the land of Korea.

• The 3407 Colgan Air Flight

This happened in the USA in the year 2009 in a place called Buffalo. This plane crashed into someone’s house, killing the man and the 49 passengers on board. The grave mistake made by the pilot was pulling instead of pushing the control column of the plane. This was when the plane was moving towards the international airport of Buffalo. Fatigue was one of the factors that led to the pilot making such a decision.

• The 3597 Crossair flight

This accident occurred in 2001 in the town of Zurich, Switzerland (Petrilli and Lamondi, 2006). This was caused by the pilot’s inattentiveness and lack of concentration; thus, their decision making was affected by this. Therefore, the plane heading from Berlin in Germany to Zurich in Switzerland went below the minimum altitude and struck trees, which led to the crash.

• The 1420 American Airlines Flight

In 1999, a plane flying from Dallas in the US towards Little Rock crashed since the pilot was going to land during a thunderstorm. This crash killed 11 people out of the total of 145 people that were on board. This, like the rest, was also caused due to impaired execution in good decision making due to fatigue, among other factors.

How the industry is trying to solve this issue with laws and regulations

Since fatigue was noted to be a huge issue in aviation safety, laws and regulations needed to be made regarding this issue, thus the NTSB has been making recommendations to the FAA regarding the fatigue issue since year 1972, and several regulations have been made such as:

• A pilot must sign a document saying that they are fit for duty, and in case they noticed to have any signs of fatigue, it is reported.
• A pilot must rest for 10 hours and sleep for a minimum of eight hours without any disruptions before taking on a flight.
• The reserve pilots must be given a minimum of 10 hours as a rest period.
• The pilot’s flight hours are limited in their flight hours per week, month, and year.
• The maximum flight hour period is nine hours during the daytime, and for the nighttime, it is eight hours.

Apart from the regulations mentioned above, it has been recommended that a safety system approach where the pilots and the operators get to be responsible for managing their fatigue is one of the best approaches (Caldwell and Neri, 2009). The FAA regularly makes non-optional updates to the Fatigue Risk Management System (FRMP) of every airline regarding fatigue management.

Technology can also deal with aviation safety regarding jetlag. An example of the use of technology is Airbus. The lights within their airplanes give the impression of natural lighting to the passengers and crew members to help with their circadian rhythm.

Lastly, things such as caffeine, using hypnotics and stimulants such as modafinil can help treat sleep dis s and help in dealing with jetlag. It is also necessary that the government and flight airlines in charge educate crew members and create awareness about jetlag and its effects.

The disruption of the circadian rhythm is a prime issue that should be addressed keenly. People should be encouraged to come up with efficient technological facilities and solutions in solving this issue.

Conclusion

Jetlag and the disruption of the circadian rhythm has been at the forefront of causes and many tragedies in the past. These factors not only cause long term physical and physiological effects to frequent travelers, but also most importantly to the aircrew that is responsible for the equipment that they operate, the cargo that they transport and the lives of many people that depend on them for travel. Unfortunately, for most people in the aviation industry, jet lag can not be avoided. Luckily more research is being conducted to assist with combating the effects of jet lag and other symptoms associated with it, along with technology that is being developed to prevent tragic accidents that these symptoms may cause.

References

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Brown, L. J. (2010). THE EFFECTS OF LIGHT EXPOSURE ON CREWMEMBER FATIGUE AND JETLAG: TO IMPROVE TRANSPORTATION SAFETY AND PRODUCTIVITY. Retrieved November 2020, from ICAS: http://www.icas.org/ICAS_ARCHIVE/ICAS2010/PAPERS/567.PDF

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