Human Factors Of Aviation Maintenance Essay


Discuss about the Human Factors of Aviation Maintenance.



The report here discusses about the human factors of aviation maintenance. The discussion begins with the explanation of the concept of Fatigue Risk Management (FRM) where the report gives a detailed overview about FRM and the various instances where fatigue has led to poor performance of the employees. The report also gives instances of the studies performed by various federations on the fatigue level of the aviation maintenance technicians (AMT). Based on the studies the report also discusses about the various errors performed by technicians due sleep deprivation. There is also discussion on the importance of type and form of fatigue risk management through the maintenance of safety and limitation in working hours. There has been further discussion on the maintenance of staff attitudes towards the reporting and sharing of information in the context of no limitation in working hour and hence hazards and risk affecting their income in future. The report further elaborates on the limitations and challenges of a compliance-based system and stresses on the fact that even if there were a regulated system in place it does not necessary imply that the technicians would not be fatigued once they were at work.

Type and Form of Typical Fatigue Risk Management

The Fatigue Risk management (FRM) is a program used for moderating the impacts created through fatigue. Conceptually, if one looks at it then FRM is a system designed to inform decisions regarding mitigating risk created through fatigue (Lerman et. al 2012). Thus, FRM contains a list of procedures and processes for maximizing alertness of the personnel and minimize performance errors that are responsible for creating hazards and risk for the crewmembers of the aircraft. Therefore, the European Aviation Safety Agency (EASA), Civil Aviation Authority of Australia (CASA) and International Civil Aviation Organization have enforced the use of FRM to ensure better performance (Dawson, Chapman, and Thomas 2012).

Thus in order to understand the importance of FRM, understanding the following instances is necessary:

  1. The mental ability of performing work related task after being awake for 16 hours is similar to having 0.05% blood alcohol concentration level.
  2. Lack of 24 hours sleep leads to mental impairment that hampers performance in a way that is similar equivalent to having 0.10% blood alcohol concentration level.
  3. Individuals with a sleep debt of 2 hours in a period of 2 weeks will have performance level similar to individual who are 16 hours awake.
  4. People working for more than 16 hours a day are more prone to accident or injury compared to people who only work for 8 hours.

There was a study conducted by the Federal Aviation Administration (FAA) on the sleeping habits of Aviation Maintenance Technicians (AMTs) in United States between 1998 and 2000. The study found that compared to the recommended eight hours of sleep per day the technicians only got five hours and five minutes of sleep (Rangan and Van Dongen 2013). In the survey, there was some 50000 hours of sleep data collected using accelerometer for determining the length of sleep for an individual. Thus, this lack of sleep amongst the Aviation Maintenance Technicians was the reason behind the errors in their performance.

However, the incident reporting service, Aviation Safety Reporting System, for mechanics, flight attendants and pilots in the United States that is under the administration of National Aeronautics and Space had some AMT reports related to fatigue which was close to 77 between the periods 1990 to 2009 (Drury 2015). Thus, a conclusion drawn from the figures states that fatigue not only led to commission errors but also omission errors.

The reality of the aviation industry is that maintenance technicians get sleep of less hours then the recommended time, an average sleep debt that is twice as compared to the national average. Thus, sleep debt associated with fatigue and sleepiness is cumulative. This implies that even losing an hour of sleep every night over a period may result in conditions that might affect performance negatively (Wang and Chuang 2014). However, the most observed errors committed due to fatigue are as follows:

  • Hinders decision making and judgment
  • Impairs skills related to communication
  • Decrease in attention span and ability to recall information
  • Results in slow reaction
  • Increases the probability of risk

Therefore, it is very necessary to initiate measures to overcome the prevalence of fatigue in the aviation industry in order to avoid risk. Fatigue Risk Management ensures using a commercial software system for designing shift rosters. Various software models consider the estimated sleep of a person and variations in circadian alertness for producing a level of fatigue that result from a certain shift pattern (Cabon 2012). The most commonly used models are:

  • Fatigue Avoidance Scheduling Tool (FAST)
  • Fatigue Audit InterDyne (FAID)
  • Circadian Alertness Simulator( CAS)

However, the limitation on duty hours is also an important factor in managing fatigue of the Aviation Maintenance Technicians (AMT). Therefore, in 2003, sleep expert professor Simon Folkard asked by the UK civil aviation authority to formulate duty hour guideline for maintenance technicians (Halford 2016). The guideline designed is as follows:

  • A 12-hour limit on shift duration should be implemented
  • There should not be extension of shift beyond 13 hours
  • There should be a break of 11 hours between the shifts
  • A work break should be implemented on every four hours basis

Maintenance of Staff Attitudes to Reporting and Sharing Information

Aviation maintenance technicians have to handle two kinds of pressure, one being the actual pressure and the other being the self-imposed pressure (Reason and Hobbs 2017). Actual pressure refers to the real pressure directly or indirectly imposed on the workers for completion of the task within specified time. While the self-imposed task refers to the target set of a team or individual for the completion of a task with a period that is less than the actual time offered.

These pressures can however be handled through:

  • Proper allocation of appropriate time for all task related to maintenance
  • There must be a comprehensive pre-task briefing carried out for outlining the task priorities
  • Ensuring both way communication for the identification and moderation of the pressure effects on behavior and performance

Thus, in the aviation industry, the busiest time for technicians happens during task and shift handovers. This is because during the handovers remaining paperwork is completed in a rush and briefings prepared for the next shift (Elavarasi and Scholar).

The safety and quality manager of the organization must ensure the implementation of Fatigue Risk Management (FRM) program that will enable the following:

  • Detection of Symptoms of fatigue
  • Identifying hazards related to fatigue
  • Accessing the health risk and associated safety
  • Implementing counter measures for safety
  • Determining tools/ approaches for reducing risks related to fatigue
  • Creating business practices based on scientific approaches for management of fatigue risk.

However, the implementation of the Fatigue Risk Management must be in phases. If the FRM designed and developed in manageable phases then the aviation maintenance technicians (AMT) can spread of their workload (Arosio 2014). However, various tools and resources enable the designing and implementing of FRM. The phases considered while developing the FRM includes fatigue risk assessment, fatigue mitigation, continuous improvement and evaluation of FRM and its promotion that ensures lowering fatigue related risk in aviation industry.

Another important aspect of FRM is that there should be regulation on the duty period of the Aviation Maintenance Technicians that will determine the time for the end of duty for a particular batch of technicians (Marais and Robichaud 2012). The control on the duty hours will enhance the efficiency the technicians. There are certain guidelines imposed on the duty hours that are as follows:

  1. The AMT should have a shift that does not exceed a period of twelve hours
  2. There should not be an extension of overtime shift beyond sixteen hours
  3. There should be scheduled duty work that includes a break time, overtime and standby for AMT that should not have an extension of 72 hours in succession of 7 days.
  4. There should be a maximum of four work hours before the scheduled break.
  5. There should be a minimum 10 minutes break period in addition to 5 minutes of break for every hour. Thus, in total there should be maximum break of 30 minutes in a day during which must assure that the process resume only after the break (Patankar 2017).
  6. The night shifts should not be more than 6 days in a week with a total duration of 8 hours including the extra hours. However, there can be 12-hour shifts for only 4 days in a week including the overtime.
  7. The night shifts that involve a 12-hour duty along with the inclusion of overtime and break should make sure that the technicians have a minimum 9 hours of rest before reporting to the next shift.
  8. There should be normal shifts of 8 hours of duty only for 5 days a week that should allow the AMTs opportunity of a minimum amount of 9 hours of uninterrupted rest before reporting to next duty (Halford 2016.).

The Challenges and Limitations of a Compliance Based System

The activities related to aviation maintenance governed by a set of procedures and rules. Therefore, safety is dependent on compliance the industry maintains with the set procedures and rules. There are many instances when such procedure not followed and there is an increase in the regularity of depressing incidents. The failure to abide by instructions remained was the key reason for the errors related to maintenance.

Although, procedures are a part human controlled system for aviation maintenance. Thus, all aspects for improving the reliability of procedural compliance taken care through the elimination of error sources. However, procedural compliance is a combined function of the documentation, human user, maintenance system and technical, cultural and physical maintenance of the environment.

Although a compliance based system is followed it does not mean that the technicians will be fatigue free once they come to work, This is because there are a number of challenges faced when the principles of FRM is actually applied in practice. However, these challenges can be faces through a pragmatic approach (Baron 2012). Most often, cultural differences and organizational constraints poses challenge in the implementation of the FRM, as they it is not possible to address them immediately and easily. These challenges also lead to the creation of fatigue complexity and hinder the understanding of the fatigue in a scientific manner. This then turn into usability issues in the management and assessment of fatigue tools and methods.

The implementation of the FRM and for it to become operational can take a time that ranges from one to two years. This may be due to the various challenges faced on the part of the organization. These challenges are as follows:

(1) Initially, in order to develop a FRM, the aviation industry must have a clear understanding of the fatigue related risk so that the industry can ensure that their FRM aligned on the evidences and the risk assessed (Weiland 2013). There has been discussions on the fact that most organizations have narrow insight for the fatigue risk profile and the realization that the potential of it employees are affected by fatigue.

(2) There is a struggle that most organizations face in order to get permission from the senior management for utilizing and dedicating resource for proactive fatigue management and assessment. Unless there is a major fatigue related risk faced, the senior management does not recognize the importance of implementation of FRM in the aviation sector (Levy et. al 2012).

(3) Lastly, when an organization does not really get the right kind of motivation from the senior management then they initiate with a safety management system instead of FRM that does not really comply with the regulations of the work time and hence the sector lack fatigue policy that actively monitors the work hours.

However, the aviation industry also faces other challenges that are associated with the development and customizing the FRM according to operational needs. These however include the alignment of the policies of fatigue management with the HR department of the industry, identification of the tools that will enable facilitation of every aspect of FRM that is proactive, predictive and reactive management of fatigue (McAfee and Brynjolfsson 2012). There are also challenges faced in customizing the fatigue tools so that they become meaningful for usage while understanding the limitations of the tools. Further, the new methods may take some time to integrate with the existing safety management system (Wachter and Yorio 2014.). However, standard organizational approach followed for the new methods so that they are recognized and may have to go through numerous levels for seeking approval. The fundamental aspect that often suffers ignorance is cultural change that is required to make the FRM functional. The development and evolvement of safety culture is the result of leadership and local conditions among other numerous factors (Rodrigues and Cusick 2012). Thus, a just culture needs promotion through the fundamental changes for successful implementation of FRM. Therefore, if an organization realizes the important aspects of safety culture then it needs engineering on a day-to-day basis through operational changes (Kinnison and Siddiqui 2012).


The report ends with a discussion on the limitations and challenges of a compliance based system there by elaborating on the fact that even if there were a regulated system in place it does not necessary imply that the technicians would not be fatigued once they were at work. There has been further discussion on the maintenance of staff attitudes towards reporting and sharing information in the context that if there were no working hour limitation then they would report hazards and risk knowing it may affect their income in future. The importance of type and form of fatigue risk management through the maintenance of safety and limitation in working hours is also discusses in the report. Through the studies the report also discusses about the various errors performed by technicians due to sleep deprivation. There are instances of studies in the report performed by various federations on the fatigue level of the aviation maintenance technicians (AMT). The discussion begins with type and form of Fatigue Risk Management (FRM) where the report gives a detailed overview about FRM and the various instances where fatigue has led to poor performance. However, the report tried to throw a light on the human factors in Aviation Maintenance.


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