When it comes to one’s safety and comfort while in flight, it is up to the aircraft crew and personnel to cater to their passengers once they step into the airplane. Each aircrew personnel have a vital role to making each flight successful and safe as one wrong move may cause the whole aircraft to plummet while in flight. There are many factors that can lead to a plane’s demise like technical malfunctions and human error. While technical malfunctions are rarely considered due to the constant check-up and maintenance of aircrafts and its machines, human error cannot easily be avoided especially if aircraft personnel would feel the effects of aircrew fatigue that could be developed through the lack of sleep, sore muscles, and long hours of work. If it is not prevent, aircrew fatigue can cause major disasters while on flight, causing millions of casualties in the process.
According to Salazar (2007) fatigue is hard to define due to the various factors that can contribute into developing fatigue. Fatigue can come from boredom to heavy physical exertion, which may even result to weariness. In some definitions, fatigue is a condition known to cause discomfort, resulting to the tendency to be inefficient in several actions. Fatigued patients often experience loss of power or capacity to stimulate their muscles to do some work. The quality of performance, task capability, and concentration is also reduced by fatigue. There are also chances that fatigue can happen acutely or in short periods of time; or in gradually in long periods if physical and mental activity is done. Insufficient sleep, stress, and overworked with insufficient rest are the common factors that present fatigue . With regards to the field of aviation, Caldwell (2004) notes that aviation fatigue is noted as one of the serious threats to aviation safety since most aircrew would have to operate in long hours without sleep due to circadian disruptions, do night duty once in flight, and perform heavy tasks despite the lack of sleep. The immediate effects of aviation fatigue are the reduction of accuracy and speed in terms of work, the incapacity to process properly information or orders, and attention loss. For pilots, fatigue can cause them to experience decreased physical activity, social withdrawal between them and their co-pilots or their staff, and can also find themselves incapable of dividing tasks between themselves and with their staff. The effects of aircraft fatigue also tend to increase for pilots as they are isolated from the rest of the aircrew, which may add to increased instances of sleepiness. Pilots may also find their performance decrease as fatigue can deteriorate their vigilance and capacity to calculate altitude readings.
Several studies had been done for the past few years to identify as to how much fatigue influences human error in aviation, each getting various results to the influence of fatigue to human error and accidents. In a study noted by Hollnagel, Paries, Woods and Wreathall (2011) fatigue can cause different consequences on aircrew activities; depending on the event fatigue becomes imminent. In the first batch of results, aircrew respondents noted that they are unable to work on specific aircraft tasks when they feel tired. Some of the activities aircrew noted that they cannot work on properly when feeling fatigued are omission to check the checklist item for the aircraft, review for errors in the Air Traffic Control (ATC) frequency readings, and proper communication between other members of the cabin crew and staff. The study also noted that aircrew utilizes strategies and behaviours to manage situations before aircrew fatigue can ensue such as additional cross-checks, early engagement of autopilot, and disengagement before landing at the airport. Usually, these strategies are also applied when one or two pilots have some doubts if they can safely land the plane when fatigued. The study also implied that in normal situations, aircraft personnel often find themselves more constraint and given more workload if they follow the additional precautions for aircraft fatigue .
In the study done by Roach, Petrilli, Dawson and Thomas (2006) they utilized simulation to identify as to how much threats and dangers aircrew fatigue can present to the passengers and staff. The results presented two sides, which reflect the capacity of aircrew fatigue to actually influence performance and function of the entire aircraft. In the study, they noted that despite the fact that aircrew had to work for extended periods while in flight and have little sleep prior to their flight; there are only a few chances that their fatigue influenced the flight and the aircraft. The researchers noted that this exceptional performance is due to the experience of the aircrew and the training they have received to combat fatigue. Once fatigue reaches a critical point wherein it effects the entire operational performance of an aircrew, the implications may be severe as they would be unable to identify threats, how to manage these threats, and correct errors on airline regulation or action .
For pilots, according to Goode (2003), aircrew fatigue can contribute to aviation accidents once they exceed the regular number of duty periods set by the aviation commission for pilots. The Federal Aviation Regulations have noted that pilots must be limited to 30 flight hours for either domestic or international flight in any given week; and they also must complete 1,000 hours per year. Scientists believe that pilots must be given the full 8 hour worth of sleep to prevent pilot fatigue to take over. The FAA policies did not allow pilots to have this sleep requirement, thus increasing the risks of aircrew fatigue. NASA had even supported that it was crucial to allow pilots to get the rest as there have been 227 schedule-related fatigue incidents throughout the span of 1994-1998 that almost caused flights to crash or get into an accident due to the pilots experiencing fatigue. Goode also noted that the National Transportation Safety Board did not cite fatigue as a cause of airline accidents, however, it did accept that fatigue had led to two major accidents: the Guantanamo Bay accident and the 1998 Little Rock accident. The debate over sleep hours for airline crew met intense study as scientists have argued fatigue due to long flight operations can easily degrade performance and safety .
Aside from the Guantanamo and Little Rock incidents, aircrew fatigue had also caused experts to identify other accidents that had been caused by fatigue-induced human error. In several studies, aviation fatigue is noted to have caused 4 to 7% of all civil aviation accidents in the US, and 4% of Army accidents. For the US Army and Air Force, studies also note that 25% of night tactical fighter Class A flight accidents were due to fatigue rather than engine failure or attack. Some of the notable accidents which have been caused by aircrew fatigue are the Korean Air 801 crash which took 228 lives, the China Airlines 006 accident which traumatized its passengers with two people critically injured, and finally the American Airlines 1420 flight which killed 11 people. In all three cases, reports have noted that crew fatigue due to lack of sleep and irregular circadian factors contributed to the accident. Nonetheless, despite the facts that aircrew fatigue is indeed a factor that contributes to human error and accidents, it is still hard to determine as to how much fatigue it would take to necessarily cause hazards to any flight. Both military and civilian aviation authorities admit that it is hard to create a fatigue countermeasure to ensure safety and at the same time, the continuous well-being of flight personnel. While there is the age-old strategy of duty-time limitations to prevent fatigue, the strategy fails to take into account the quality of sleep of the crew, the sleep periods the crew had done for the past flights, and finally the circadian rhythms the staff had to accommodate while in flight .
Aviation fatigue, in a general sense, can present several dangers and changes for aircrew if it is not immediately remedied. Personnel could find themselves feeling restless, weak, and their performance quality decreased. For pilots, fatigue can cause them to experience decreased physical activity, social withdrawal between them and their co-pilots or their staff, and can also find themselves incapable of dividing tasks between themselves and with their staff. Several studies have been done as to how aircrew or aviation fatigue presents risks to passengers. On one study, it has been noted that aircrew fatigue can influence a flight depending on the situation it mostly arises. While there are countermeasures placed to fight fatigue, the countermeasures itself become a reason for fatigue. Aircrew also do not easily show signs of fatigue due to experience, but, once they succumb to fatigue, they would find themselves unable to assess threats and restore order once an error is in place. In reports filed by the US Air Force and civilian aviation authorities, aircrew fatigue is to blame for some of the world’s largest aviation casualties. Many are still having doubts as to what effective strategy can be used to prevent aviation fatigue from becoming a hazard to both commercial and military flights.
It may be difficult to prevent succumbing to fatigue whether one works in aviation or in the office.As of today, there is still no definite means to prevent or eliminate the chances of aircrew fatigue due to the difference of each crew and their rest requirements. However, many have noted that fatigue can be prevented with a good night sleep, rest, and even training since aircrew would need to stay sharp. While there is still no definite means to prevent aircrew fatigue from causing accidents, prevention can be done in small means. One can also appreciate how much effort aircrew personnel take into consideration to ensure that passengers are well-taken care of despite the long hours above the clouds, and their frequent errands to run to ensure the plane runs smoothly while in flight and after the flight. Without them, it is possible that passengers cannot experience a safe and comfortable flight to their intended destinations.
Caldwell, J. (2004). Electroencephalographic indicators of impaired aviator status during sleep deprivation`. In I. o. Academies, Monitoring Metabolic Status: Predicting Decrements in Physiological and Cognitive Performance (pp. 392-399). Washington, DC: National Academies Press.
Goode, J. (2003). Are pilots at risk of accidents due to fatigue? Journal of Safety Research, 1-5.
Hollnagel, E., Paries, J., Woods, D., & Wreathall, J. (2011). Resillience Engineering in Practice: A Guidebook. Surrey: Ashgate Publishing.
Roach, G., Petrilli, R., Dawson, D., & Thomas, M. (2006). The effects of fatigue on the operational performance of flight crew in a B747-400 simulation. Adelaide: Australian Research Council.
Salazar, G. (2007). Fatigue in Aviation. Oklahoma: FAA Civil Aerospace Medical Institute.