This paper explores instances in which aircraft incidents, accidents, and fatalities were attributed to fatigue experienced by the responsible aircraft maintenance technicians. Further, this paper explores the existing regulations regarding fatigue and fatigue management both federally and within corporations. This paper also explores the lapses in protection against aircraft maintenance fatigue. This paper aims to answer the following questions: What are some examples of aircraft incidents as a result of fatigue experienced by the maintenance technicians?; How was this cause determined?; What are some examples of mistakes made by fatigued technicians?; What was the scope and severity of these accidents?; What are some of the regulations created or sanctions against different organizations as a result of this occurring?; What measures have been taken to mitigate this problem?; Through research, I expect to find a wide variety of aircraft incidents occurring because of technician fatigue, all ranging in severity. My research will be conducted using the internet and our class resources.
When considering human factors in aviation, fatigue in aviation maintenance technicians is a difficult but critical component. While resources and inventory can be managed and education recorded and proved, there is no universal test that can supply a quantitative result representing a technician’s fatigue level. There is no universal level at which every person becomes fatigued or unable to work in a satisfactory capacity which makes fighting fatigue difficult. Aircraft mechanic fatigue has been a contributing, even main, factor in several accidents.
To understand the scope of the potential mistakes made by a fatigued technician, it is important to understand the duties of an aircraft maintenance technician (AMT). The duties of an AMT can vary depending on what company they work for, if they serve in a particular department, or specialize in a certain field. Regardless, they are required to inspect the aircraft, diagnose problems with the aircraft, test the systems, and find a way to repair the problem according to specifications and technical manuals. They are required to inspect parts for signs of damage or wear and replace these parts as well as perform regular preventative inspections and maintenance. AMTs are required to record their work and sign off on any work they have done on the aircraft and are expected to follow all FAA regulations and guidelines. Occasionally, an AMT may only make a thorough inspection on one aircraft only to find no faults, and then on the next aircraft be required to replace an entire engine component. The work varies greatly from plane to plane and day to day. Technicians regularly work shifts at any time in the day or night, weeks or weekends. In order to keep up with airline aircraft demands and flight schedules, AMTs will be expected to inspect, diagnose, and repair all hours of both day and night.
To understand the dangers of fatigue, it is important to understand the different types of fatigue and what can cause fatigue. It is also critical that both the aircraft maintenance technician and their supervisor keep these types in mind so they can anticipate any signs or symptoms of fatigue. There are several kinds of fatigue: transient fatigue, which is characterized by extreme lack of sleep; cumulative fatigue is characterized by repeated instances of getting a reduced amount or reduced quality of sleep across several days; and circadian fatigue, which is reduced energy and performance quality during night time hours (Fatigue, n.d.). Because of the demanding nature of the aviation maintenance industry, AMTs are at risk of suffering from each of these different types of fatigue. Aircraft maintenance technicians are expected to work night shifts and overtime which can greatly affect, or even completely change, their sleeping schedule. For example, in a study conducted for Transport Canada, it was found that on average their AMTs were working more than 50 hours a week, many shifts were 12 hours or longer, and many of the technicians came in on their days off (Werfelman, 2008). These technicians are in great danger of suffering from fatigue with consistent overtime.
Several notable aircraft accidents demonstrate the potential consequences of a fatigued aviation maintenance technician making a mistake. For instance, in 1990, British Airways Flight 5390 experienced a blown-out windscreen and one of the pilots was sucked almost completely out of the plane (Calvacante, 2014). This occurred shortly after takeoff, during the ascent of the aircraft. One of the flight attendants held onto the pilot until the plane was able to land safely. In the post accident investigation, the maintenance logs showed that the most recent maintenance took place in the very early hours of the morning and it was determined that the aircraft mechanic technician was suffering from circadian fatigue. The mechanic used the incorrect bolts when securing the windscreen and in his fatigue did not realize his mistake. While this incident did not result in a fatality, the occurrence of a blown out windscreen could easily have even worse consequences.
Another accident showing the consequences of AMT fatigue occurred in May 2013. An A319 operated by British Airways was forced to make an emergency landing after the covers of the engines flew off and a fire was ignited (Topham, 2015). The engines burst into flames and wreckage weighing up to 37 kilograms was thrown across the runway at London Heathrow airport. It was discovered that the technicians had left the fan cowls unlatched when leaving the aircraft, intending to return and top off with oil. However, they returned to the incorrect aircraft, an A321, and the flaps were left open. One of the technicians had worked a reported 70 hours over seven consecutive days and nights. The incident occurred during a night shift, the technicians second 12 hour overtime night shift. It was declared in the post accident investigation that technician fatigue was the cause of the error.
Flight crews have long been the targets of fatigue fighting regulations with the FAA, airlines, and customers acutely aware of the long flight hours and demands placed on pilots and their crews. Even though AMTs are routinely required to work extra hours or during the night, they are rarely included in these regulations (Lombardo, 2011). In audits conducted as recent as 2000, it was noted that less than 10% of corporations had duty limits for aviation maintenance technicians and those that did typically put those limits between 12-14 hours per day (Werfelman, 2008). Despite the lack of attention paid to the long duty hours and lack of regulations to prevent fatigue in the maintenance line, it was found in a separate survey that 82% of surveyed human factor program managers believed fatigue to be a big issue in aviation maintenance. In that same survey, only 25% of respondents said they had a fatigue management system incorporated into their safety training. The industry has acknowledged the problem but the response in terms of regulations and preventative measures has been slow.
While fatigue experienced by aviation maintenance technicians is not an unknown or improbable issue, the aircraft accidents coupled with the lack of regulations and corporate limitations show that there is still a lot to be done in order to mitigate this problem. The inability to quantitatively measure fatigue and the demanding nature of the industry makes it difficult to adequately approach this problem.
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Lombardo, D. A. (2011, May 11). FAA Expresses Concern over Technician Fatigue. Retrieved February 26, 2018, from https://www.ainonline.com/aviation-news/business-aviation/2011-05-11/faa-expresses-concern-over-technician-fatigue
Topham, G. (2015, July 13). Tired technicians' plane mixup led to inflight engine fire, inquiry finds. Retrieved February 26, 2018, from https://www.theguardian.com/uk-news/2015/jul/13/tired-technicians-plane-mixup-engine-fire
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Werfelman, L. (2008, April). Working to the Limit. AeroSafety World, 14-18. Retrieved February 28, 2018, from http://www.flightsafety.org/asw/apr08/asw_apr08_p14-18.pdf