CC BY
66
УДК 629.735.067 = 111
ЧЕЛОВЕЧЕСКИЙ ФАКТОР В ТЕХНИЧЕСКОМ ОБСЛУЖИВАНИИ
ВОЗДУШНЫХ СУДОВ
Д. В.Телегин, Л. В. Фомин Научный руководитель - П. Р. Чирков
Сибирский государственный аэрокосмический университет имени академика М. Ф. Решетнева
Российская Федерация, 660037, г. Красноярск, просп. им. газ. «Красноярский рабочий», 31
Е-mail: [email protected]
Ошибки в техническом обслуживании воздушных судов не являются самой частой причиной лётных происшествий. Однако большая степень личной и коллективной ответственности за свою работу, условия выполнения работ, создающие дополнительный стресс, технические и психологические ограничительные факторы часто ведут к ошибкам и мелким промахам в работе персонала, обслуживающего воздушные суда. Методы отслеживания и борьбы с влиянием человеческого фактора в этой сфере постоянно дорабатываются и усовершенствуются.
Ключевые слова: человеческий фактор, техническое обслуживание, надёжность, ограничение, предотвращение, коммуникация, усталость, упущение.
HUMAN ERROR IN AIRCRAFT MAINTENANCE
D. V. Telegin, L. V. Fomin Scientific supervisor - P. R. Chirkov
Reshetnev Siberian State Aerospace University 31, Krasnoyarsky Rabochy Av., Krasnoyarsk, 660037, Russian Federation E-mail: [email protected]
There is evidence that maintenance of different aircraft systems is nowadays contributing to an increasing proportion of accidents. Maintenance is a major point of direct interaction between people and technology, where human capabilities and limitations can have a significant impact on system safety and reliability. Maintenance tasks are performed incorrectly or are omitted due to human error. Parts are installed incorrectly, found missing, and there are no checks. These actions occur in the context of local conditions - communication, workplace conditions, and equipment. Ways of counteracting these aggravating factors is being in progress, and new methods of preventing human errors are being implemented.
Keywords: maintenance, safety threats, human factor, human error, reliability, limitation, omission, stress factors.
Improper maintenance is the cause of a significant number of aviation accidents and incidents. The cause of it is that a certain percentage of maintenance tasks are carried out incorrectly or not performed at all due to human error. The mistakes include parts installed with some inaccuracy, parts not installed, and missing checks. The majority of maintenance errors do not lead to accidents; however, a small proportion presents serious threats to safety. The mistakes of maintenance personnel can be more difficult to detect as compared to mistakes made by flight crews, and often remain latent, affecting the safety of operation of aircraft only in some future situations.
Maintenance of different aircraft systems, which become more and more complex, has already caused an increasing number of accidents. As automated systems become increasingly common, people are performing only indirect control of equipment and systems. This involves more complex interaction between people and technology, where human abilities and drawbacks can also have an impact on the general technological safety and reliability.
Aircraft come with manuals that specify their performance. Procedures too, have been created by people and can be documented and understood. But when it comes to people, they are system elements that
Секция «Эксплуатацияи надежность авиационной техники»
come with no operating manual or user's instructions, and they often perform in ways unpredicted by the system designers. Some of their errors can be easily explained, an arithmetic error for example, while others are harder to predict. Although individuals differ, researchers have discovered general principles of human performance that can help to create safer and more efficient systems [1] Introducing the concept of "human factor" and the disclosure of its contents, along with the existing concept of "personal factor", was primarily due to the successes achieved in the engineering and social psychology in the areas of research of the interaction of the operator with technical devices, the environment, etc. [2].
Maintenance personnel meet a set of human factors unique for the industry. Maintenance technicians work in an environment that is more trying than most other jobs in engineering. The work may be carried out at heights, in confined spaces, in hard cold or strong heat. The work can be physically strenuous, at the same time requiring high-level skills and attention to detail. Maintenance technicians often spend more time preparing for a task than actually carrying it out. Filling in all sorts of documents is a time-consuming activity, and maintenance engineers often spend nearly as much time on paperwork as on maintenance itself. Complex procedures require good communication and coordination, yet verbal communication can be difficult due to noise levels and the use of hearing protection. The work often means fault diagnosis and problem solving within a limited period of time, particularly at the gate. Maintenance personnel also face unique sources of stress. Air traffic controllers and pilots can leave work at the end of the day and never worry about it anymore. When maintenance personnel leave work at the end of their shift, they know that the work they performed will be relied on by crew and passengers for months. The emotional burden on maintenance personnel whose work has been involved in accidents is largely unrecognized outside the aircraft maintenance institutions. On more than one occasion, maintenance personnel have taken their own lives following aircraft accidents caused by maintenance error [1].
Accidents or incidents are usually caused by the actions of operational personnel. However, these actions occur in the context of local conditions, such as communication, workplace conditions, and equipment. The task environment also includes risk controls. They are procedures, checks or precautions aimed at managing hazards that threaten safety. Risk controls, local conditions and individual actions are often influenced by organizational factors such as company policies, the ways the resources are used, and management. The use of the term 'human error' should not imply that we have a problem with people. But naturally, as the workload increases the specialist tends to employ more procedures which are less time-consuming, together with a progressive reduction to the minimum of information and the relaxation of certain self-imposed qualitative criteria. It is evident that the number of decisions to be made becomes a stressful condition when the worker's decision-making capacity and the level of concentration are overloaded. Psychological error models categorize errors according to the person's intentions at the time of their action. An advantage of psychological descriptions is that they help to place the error in its organizational context, and then develop appropriate countermeasures. For example, if it is concluded that someone did not perform a necessary action because he or they forgot, there should be the prompts to memory, such as documentation. If, on the other hand, a person did not perform a necessary action because he or they thought the procedure did not require it, there should be more training hours for the personnel.
There are scheduled and unscheduled maintenance tasks. The distinction between these two categories has significant implications for maintenance human factors. Scheduled maintenance tasks are performed regularly, and so are familiar routines for maintenance personnel. Experienced personnel can hardly make mistakes related to a lack of knowledge or skills on a familiar preventative task. They are mostly the consequences of breakdowns in teamwork, like everyday 'absent - minded' mistakes of forgetting to install components. Unscheduled tasks are usually corrective in nature, and are performed in response to unplanned events such as aircraft damage or component failure. Although some unscheduled tasks are minor, others require extensive system knowledge, problem solving and specialized skills.
Delays to aircraft caused by maintenance can impose significant costs on operators, and much maintenance work is carried out under time constraints. Sometimes it is really difficult to deal with the pressures imposed by aircraft departure times and maintenance schedules. Time pressure is particularly likely to lead to memory lapses and unwanted changes in repair procedures, such as where an engineer uses a shortened list of checks to enable an aircraft to depart on time [1].
Few maintenance workers work completely alone, and to perform their work successfully, they must coordinate with other operational personnel. Coordination problems such as misunderstandings, ineffective communication, and incorrect evaluations are reported in many reviews of maintenance incidents. Many maintenance tasks cannot be completed in a single shift. Aircraft maintenance workers frequently need to accept work in progress from colleagues, and pass incomplete work to an incoming shift. The need to
accurately and effectively transfer information, in many cases without face-to-face contact, is a crucial aspect of maintenance work [1]. All these hazards together cause serious stress.
To be balanced, stress is not all bad. We need to be stimulated in order to stay active and feel productive. The absence of stress leads to boredom, which is an undesirable condition for technologically complex professions. Too much stress, however, causes overload and the work will suffer. It is difficult to control stress, but not entirely impossible. Specialists say that the first step in coping is to identify stressors and the symptoms that occur after exposure to those stressors. Coping efforts can be focused toward the stressor or the emotions that arise as a result of stress, but the most effective strategy is to deal with both the stressor and its emotional impact. Reducing the negative emotional impact of the stressor removes many of the barriers that obstruct the problem-solving thought processes [3]. The first step is to learn to recognize the symptoms of stress, then there come a number of countermeasures such as preparing and planning your work actively, taking care of the physical aspect: food, sleep and exercise, keeping workload under control.
In order to understand and ultimately prevent accidents, it is necessary to trace the chain of causes back through all the elements of the system including organizational influences. This is often referred to as root cause analysis. This analysis identifies two main types of risk controls connected with maintenance errors - preventative controls and recovery risk controls. Preventative risk controls are intended to reduce the chance of unwanted events such as human error. Recovery risk controls are designed to detect and recover from a dangerous situation once it has started to develop. Functional checks and duplicate inspections are examples of procedures designed to detect maintenance errors [1]. Less formal approaches also have a role in preventing errors. For example, a read-back of verbal instructions can be effective in reducing communication errors.
A significant problem facing maintenance organizations is how to encourage the disclosure of maintenance incidents and not to leave them unknown to management. Despite the extensive documentation that accompanies maintenance, the day-to-day work of maintainers may be less visible to management than the work of pilots or controllers. While all involved in aviation safety must be prepared to take responsibility for their actions, response in the form of punishment to genuine errors is the wrong way of problem-solving. The concept of 'just culture' has been promoted, in which some extreme violations will result in discipline, however most will not [1]. Progress is being made towards error reporting systems that help maintenance engineers to deal with genuine mistakes without fear of punishment. The issues of blame and justice should not be applied just to maintenance personnel on the hangar floor. Managers and supervisors are also responsible for the performance of the personnel who report to them. When workplace violations occur, measures should be taken not only to point them out to those directly involved, but also to managers. For example, if an incident was a routine rule violation, managers should be called to account for their failure to ensure precision of the workers' actions, or their failure to change the rule if it was an unnecessary one. The probability of maintenance error can be minimized by identifying and counteracting error-producing conditions in the organization. Airlines can learn to manage the threat of maintenance error in the same way they deal with natural hazards such as weather [1].
Библиографические ссылки
1. Hobbs A. An Overview of Human Factors in Aviation Maintenance - Australian Government/ Australian Aviation Safety Bureau // ATSB Transport Safety Report: Aviation Research and Analysis Report AR-2008-055 Final, 37 p.
2. MacBurnie E. (1999). Human Factors Today: managing human error. ICAO Journal, 51(8), 5-30.
3. MacBurnie E. (199б). Human Factors in Aviation. ICAO Journal, 51(8), 4-29.
© Телегин Д. В., Фомин Л. В., 2015
