Fatigue In Aviation Research Articles

Human fatigue in the aircraft maintenance environment

The complexity of technologies in modern aircraft makes their maintenance a critical function. The work environment is diverse and dynamic, with uninterrupted working hours and multiple demands, which can result in inadequate sleep and excessive workload for Aircraft Maintenance Technicians. This causes fatigue and increases the likelihood of human errors, directly affecting safety. A study was conducted with 312 participants to investigate how fatigue affects maintenance professionals. Participants responded to questionnaires that included four culturally validated scales to measure levels of fatigue, sleepiness, workload, and quality of life. Statistical analyses were performed to correlate sociodemographic factors and work-related aspects with levels of fatigue. The results revealed a positive and significant correlation between fatigue, sleepiness, and workload, and a significant negative correlation with quality of life. It was found that 52.9% of participants experienced some level of fatigue, highlighting the prevalence of fatigue among the sampled population. Statistically significant differences were also found in participants aged 36 to 50, those working shifts, and those working during nighttime hours. Therefore, regulations and practical measures are needed to assess and manage fatigue-related risks, tailored to the aircraft maintenance environment, given that current regulations on human fatigue in aviation primarily focus on flight crew, paving the way for potential changes in the European Aviation Safety Agency regulations.

Integrated Modeling of Fatigue Impacts on C-17 Approach and Landing Performance

ABSTRACT Objective The current effort develops an initial integrated model of fatigue in the context of C-17 approach and landing operations. Specifically, we integrate a biomathematical fatigue model with a task network model to estimate pilot performance degradation. Background Fatigue risk management is a critical process in aviation and flight deck operations, given its dramatic impact on aviation safety and pilot health. Biomathematical fatigue models are useful tools in several aviation fatigue risk management programs that can be embedded in electronic device applications. However, these tools are limited in terms of identifying specific performance outcomes affected by fatigue, as well as individualizing fatigue estimates to individual pilots. Integrating computational cognitive models and biomathematical fatigue models can help address these issues. Methods Forty-four aircrew members completed the study with 10 performing 33 landings with sets of corresponding actigraph data and C-17 performance metrics. We developed a task network model of C-17 approach and landing operations and integrated biomathematical fatigue model predictions based on actigraph data from the aircrew. We then compared predictions from this integrated model with C-17 performance metrics from the missions. Results We successfully predicted delays in setting flaps, landing gear, and engaging the speed brake. Conclusion After further development and validation, this integrated model can be implemented within an application to provide real-time information on pilot fatigue and expected performance on specific aircraft operations.

Understanding Factors Underlying Fatigue among Collegiate Aviation Pilots in the United States

An increase in evidence-based studies into the deleterious effects of fatigue on flight operations has been reported by key aviation groups globally. The collegiate aviation flight training environment has not been researched at the same level when compared to military and airline operations. College aged students are unique in the sense that they are tasked with classwork, studying, participation in student organizations, social activities, and often have part time jobs within and outside of the academic environment. These conditions may cause errors, incidents, accidents, poor academic performance, and undesirable health metrics. The purpose of this study was to understand fatigue as a multi-factorial dimension and to assess potential relationships among these factors using hypothesized measurement models. The research team distributed the Collegiate Aviation Fatigue Inventory II (CAFI-II) to eight small, medium, and large collegiate aviation programs in the United States. The CAFI-II primarily focuses on fatigue awareness, causes and symptoms of fatigue, and lifestyle choices. Four hundred and twenty-two (n = 422) valid responses were obtained. Results suggested a direct predictive relationship between fatigue in collegiate flight training and the perceptions of respondents of conditions that are known to cause fatigue. Findings also suggested that respondents who had a favorable perception of fatigue risk and management programs had a better understanding of the causes of fatigue.

Fatigue in Aviation: Safety Risks, Preventive Strategies and Pharmacological Interventions.

Fatigue poses an important safety risk to civil and military aviation. In addition to decreasing performance in-flight (chronic) fatigue has negative long-term health effects. Possible causes of fatigue include sleep loss, extended time awake, circadian phase irregularities and work load. Despite regulations limiting flight time and enabling optimal rostering, fatigue cannot be prevented completely. Especially in military operations, where limits may be extended due to operational necessities, it is impossible to rely solely on regulations to prevent fatigue. Fatigue management, consisting of preventive strategies and operational countermeasures, such as pre-flight naps and pharmaceuticals that either promote adequate sleep (hypnotics or chronobiotics) or enhance performance (stimulants), may be required to mitigate fatigue in challenging (military) aviation operations. This review describes the pathophysiology, epidemiology and effects of fatigue and its impact on aviation, as well as several aspects of fatigue management and recommendations for future research in this field.

Development of a multicriteria decision-making model for selecting optimal aviation fatigue measurement methods

Human fatigue has been proved to directly cause or contribute to a significant share of aviation accidents. Although fatigue measurement is a major input to any solution that targets reduction of fatigue adverse influences on aviation operations, there is a critical lack of evidence on what optimum sets of fatigue measurement strategies could be applied given the vast organizational and operational differences between various industry players. The current study utilizes the published aviation safety literature, the technology acceptance model and expert opinion to propose a new multicriteria decision model, the aviation fatigue measurement selection model, to decide on what fatigue measurement methods are most suitable for each aviation operator. The model addresses the validity, user acceptance, cost and other limitations of each currently acknowledged fatigue measurement method. The model was then applied through comprehensive scenario-based simulations and was found to be sensitive to changes in user preferences and valid.

Understanding Fatigue within a Collegiate Aviation Program

ABSTRACT Objective: The purpose of this study was fivefold: to investigate the symptoms that would prompt collegiate aviation pilots perceive they are fatigued; to investigate the time of the day they are most fatigued; to investigate their academic and personal schedules; to investigate the methods collegiate aviation pilots utilize to ensure they are fit to fly; and to investigate whether they have received any academic and/or flight fatigue identification and management training. Background: Fatigue is a pervasive safety hazard in aviation affecting several aspects of flight crew members’ ability to perform their job. Fatigue in aviation and its consequences has been researched across military and commercial operations, but until now Part 141 collegiate aviation pilots have been neglected. Method: Data were collected using an online survey questionnaire self-report questionnaire (N = 122) consisting of items investigating fatigue identification and management by Part 141 collegiate aviation pilots. Results: Sixty percent of the participants usually experience the mental and physical symptoms of fatigue during flight activities. A finding of concern was that 43% of the participants indicated they had not received any training in fatigue identification and management during ground and flight activities. Conclusion: The safety management of fatigue in a Part 141 collegiate aviation environment is a safety issue that warrants further research, and training and education.

Contributory Factors of Fatigue Among Collegiate Aviation Pilots: An Ordinal Regression Analysis

Fatigue is a pervasive safety hazard in aviation affecting several aspects of a pilot's’ ability to safely perform their jobs. Several factors can contribute to fatigue, including inadequate sleep, stress, long work hours, excessive workload, and inadequate nutritional habits. In addition to flight training, some factors including academic, social, part-time work, and emerging time management skills are unique for Title 14 Code of Federal Regulations (CFR) Part 141 collegiate aviation pilots. By utilizing the Collegiate Aviation Fatigue Inventory (CAFI-II) at eight flight programs (n = 422), the current study examined factors such as fatigue training received, time spent working/studying and socializing, and enrollment level. Ordinal regression was used to assess the odds ratios of fatigue among demographic study groups. Notable results indicated approximately fifty percent of respondents reported not having fatigue training, Juniors and Seniors reported a less frequency of fatigue training when compared to the other two enrollment levels, and they also had a higher probability of flying while fatigued. The researchers suggested improved targeted training as well as recommendations for fatigue risk management strategies.

Health Risks and Potential Predictors of Fatigue and Sleepiness in Airline Cabin Crew.

Background: Aviation pilots and cabin crew regularly undertake shift work, and may experience circadian disruption, restricted sleep, sleepiness and impaired health. Research on aviation fatigue and sleepiness has focused on pilots, with less being known about cabin crew. This study aimed to identify likely predictors of fatigue, sleepiness, shift work disorder (SWD) and depression in cabin crew. Methods: An online anonymous survey was distributed to active cabin crew around the world. It measured sleepiness, fatigue, and screened for insomnia, depression and SWD. Information on individuals’ habits and work schedules were collected. Results: 930 valid responses were analysed. 63.5% of the sample had abnormal levels of fatigue and 46.9% experienced excessive daytime sleepiness. 68.0% were at risk for SWD, 57.7% screened positive for insomnia, and 40.0% for depression. Caffeine and use of alcohol and drugs for sleep were independently associated with insomnia and SWD (p < 0.05), whereas, type of route (international, domestic, both) and number of duty days per week predicted fatigue (p < 0.05). Conclusions: Cabin crew had a high prevalence of fatigue, sleepiness and elevated risk for SWD, insomnia and depression. Many cabin crew engaged in behaviours detrimental to good sleep hygiene, highlighting targets for future interventional studies.

Why Residencies Should Fly: Towards a Logical Approach to Duty Hour Reform.

Since 2011, aviation has revolutionized their approach to safety. The aviation industry has adopted a multi-faceted approach to improve safety through decreasing duty hour limits and implementing processes to mitigate fatigue-related errors as well as creating cultural shifts in responsibility for safety. These changes have been guided by data generated by quality-improvement methodology. In contrast, duty hour limits in graduate medical education have not yet seen dramatic data-driven reform. Key advancements in aviation fatigue mitigation and implications for residency education are explored in this article. Scientifically based processes to optimize duty hours, quality-improvement strategies to iteratively monitor and reform duty limits, systematic change focusing on a just culture, and financial disincentives and incentives as a catalyst for change are discussed.

Pilot Fatigue Risk Analysis: Conceptual Study at Flight Operation of Garuda Indonesia’s Boeing 737 Pilots

Fatigue in aviation is a critical field, since it will influence many passengers’ safety. Garuda Indonesia is a Flag Carrier of the largest archipelago national, which cover three different time zones. This study aims at analyzing the airline pilot’s fatigue contributors at Boeing 737 fleet, the short to medium haul flight operation workhorse of Garuda Indonesia, which fly domestic and regional flights. While in the aviation industry, most of the human factors related fatigue research focused on long-haul pilots, since the exposure of their duties towards jet-lag. However, short-haul pilots experience of flight operation of less than 8 hours flight time per flight sector, multiple flight sectors a day, with the set of two pilots for each rotation pattern causes their elevated levels of fatigue. Classification of fatigue are; physical decline, mental decline, and rest defects. Fatigue of Garuda Indonesia’s Boeing 737 pilot is affected by; duty assignment, personal lifestyle, work environment, rest environment, unresolved stress, and illness. Finding the variables and the phenomenon can also contribute to pilot fatigue management.

Fatigue Monitoring Tool for Airline Operators (FMT)

Abstract A Fatigue Monitoring Tool (FMT) model was constructed for an operational airline in order to manage the fatigue levels of their crews in accordance with Fatigue Risk Management System (FRMS) practices. This article describes the implementation of the Fatigue Monitoring Tool model and the airline’s aims to put the recent scientific findings on aviation fatigue into practical use. The model consists of proxy points allotted to various duties and rest periods.

Fatigue Monitoring and Management across Different Industries

Fatigue, often defined as a physiological state of reduced mental or physical performance capability resulting from sleep loss, circadian phase, or workload (physical or cognitive), has been implicated as a critical risk factor resulting in severe injuries and accidents. A great deal of research has been done into the identification, measurement, and management of fatigue, however it is still poorly understood. This may be due to the characteristics and variability of work conditions across different industries; for example, fatigue in manufacturing is largely related to physical demands, and in aviation fatigue is related to sleep and shift-work. This panel will comprise of academics and practitioners across manufacturing, healthcare, transportation, aviation, and oil and gas industries. Topics covered within each industry will include fatigue causes and consequences, existing fatigue monitoring/management practices, barriers to fatigue monitoring and management, and recommendations/discussions around improving the current state.

Fatigue on the flight deck: The consequences of sleep loss and the benefits of napping

The detrimental effects of fatigue in aviation are well established, as evidenced by both the number of fatigue-related mishaps and numerous studies which have found that most pilots experience a deterioration in cognitive performance as well as increased stress during the course of a flight. Further, due to the nature of the average pilot's work schedule, with frequent changes in duty schedule, early morning starts, and extended duty periods, fatigue may be impossible to avoid. Thus, it is critical that fatigue countermeasures be available which can help to combat the often overwhelming effects of sleep loss or sleep disruption. While stimulants such as caffeine are typically effective at maintaining alertness and performance, such countermeasures do nothing to address the actual source of fatigue – insufficient sleep. Consequently, strategic naps are considered an efficacious means of maintaining performance while also reducing the individual's sleep debt. These types of naps have been advocated for pilots in particular, as opportunities to sleep either in the designated rest facilities or on the flight deck may be beneficial in reducing both the performance and alertness impairments associated with fatigue, as well as the subjective feelings of sleepiness. Evidence suggests that strategic naps can reduce subjective feelings of fatigue and improve performance and alertness. Despite some contraindications to implementing strategic naps while on duty, such as sleep inertia experienced upon awakening, both researchers and pilots agree that the benefits associated with these naps far outweigh the potential risks. This article is a literature review detailing both the health and safety concerns of fatigue among commercial pilots as well as benefits and risks associated with strategic napping to alleviate this fatigue.

Aviation Fatigue

Researchers and operations professionals convened on November 9, 2012, to discuss an agenda for research in aviation fatigue. While the working groups had different specific issues related to fatigue, there was common ground in the work surrounding fatigue and the technologies that are being developed. The discussion highlighted the following issues, which are recommended for further research: Strategies for changing the culture for fatigue self-report and self -monitoring. Policy shifts to account for consecutive nights worked and the effects of circadian rhythms. Tools for self-fatigue assessment, particularly based on objective measures. Tools for minimizing fatigue in scheduled operations and on-demand operations planning. Fatigue models that account for individual differences and account for the dynamic nature of fatigue in different operational contexts. Benchmarking and validation of proposed fatigue risk management systems in operational settings. This panel is intended to expand this discussion of the human factors-related issues in fatigue of specific concern to the aviation community, in particular recommendations 3, 4, 5, and 6, to a wider Human Factors and Ergonomics Society audience.

Battling Fatigue in Aviation: Recent Advancements in Research and Practice

Despite knowledge gained through decades of research, fatigue due to insufficient sleep remains an ingrained part of military and commercial aviation and represents a major threat to the health, safety, and effectiveness of aircrew. Long duty periods, high workloads, circadian disruptions, and insufficient recovery time between flights ensure sleepiness is a continued problem for both civilian and military aircrew. The majority of our knowledge concerning the effects of fatigue is gained from acute, total sleep deprivation laboratory-based studies which describe results in terms of the average individual's response to total sleep loss. However, in operational environments, limited sleep over many days, termed chronic sleep restriction, is more commonly experienced than acute, total sleep deprivation, casting some doubt on the operational applicability of many previous studies. Furthermore, recent studies have identified strong individual differences in fatigue resistance. Our understanding of the effects of chronic sleep restriction and the individual differences in response to fatigue is currently limited in comparison to that of acute sleep deprivation. In this review, we identify the substantial progress made over the last 2 decades in closing these gaps. Advances in understanding the effects of chronic sleep restriction, the recovery timeline associated with sleep loss, and individual responses to sleep loss represent a critical step in the improvement of current, and the formulation of future, countermeasures in the aviation environment. Adjustments to duty rotation and crew scheduling, refinement of biomathematical models of fatigue, and application of currently available countermeasures are the most immediate of these improvements.

Fatigue in Aviation: A Survey of the Awareness and Attitudes of Indian Air Force Pilots

Sleep loss and circadian rhythm disruptions cause fatigue in aircrew and thus affect flight safety. Intervention programs for fatigue in any organization should be based on relevant indigenous data. This study was undertaken to develop an understanding of fatigue among aircrew of the Indian Air Force (IAF). This questionnaire study was carried out at the Institute of Aerospace Medicine, Bangalore, in which a total of 83 military fast jet aircrew participated. The mean age of the respondents was 28.9 years (SD = 3.7) with an average military service of 7.2 years. The majority of the aircrew tended to sleep more in the afternoon and longer in the night on holidays and weekends. One third of the aircrew believed that they could perform in peak efficiency even with 1 to 2 hr sleep loss. A similar number stated that they had felt sleepy or drowsy in the cockpit due to sleep deprivation. Aircrew rated decreased attention, increased reaction time, lapses in concentration, and poor aircraft handling as important outcomes of fatigue. Tea or coffee was the preferred countermeasure. They were unanimous in the felt need for more information dissemination on fatigue. There appears to be complacency among aircrew who believe that they may be able to operate with full efficiency despite 1 to 2 hr of sleep loss. They are not well versed about the beneficial effects of napping when fatigued. More emphasis should be placed on recurrent education of aircrew on such issues of aeromedical importance.

Fatigue in aviation

Pilot fatigue is a significant, but often under-reported problem in both civilian and military aviation operations. Although estimates vary, official statistics indicate that fatigue is involved in at least 4-8% of aviation mishaps, and surveys of pilots and aircrew members reveal that fatigue is an important concern throughout today's 24/7 flight operations. Regulatory efforts aimed at limiting flight hours and ensuring at least minimal periods of crew rest have to some extent mitigated fatigue-related difficulties in the cockpit, but it is clear that much remains to be done about this insidious threat to air safety. Scheduling factors, sleep deprivation, circadian disruptions, and extended duty periods continue to challenge the alertness and performance levels of both short-haul and long-haul pilots and crews. Solutions for these problems are not straightforward, but they can be developed through the cooperative efforts of scientists, regulators, managers, and the pilots themselves. Over the past 20 years, scientific understanding of human sleep, fatigue, and circadian rhythms has expanded considerably. The thorough integration of this new knowledge into modern crew-resource management practices will facilitate the establishment of optimal crew scheduling routines and the implementation of valid aviation fatigue countermeasures.