Aviation's Key Profession and Sector; AIRCRAFT MAINTENANCE, Part: 3

Scientific Disciplines Required and Utilized in Aircraft Maintenance

Summary

Aircraft Maintenance activities require a multi-disciplined and interdisciplinary context and concept business model. The "Flagship" of this model is Aircraft Engineering. Because it is not possible to carry out the maintenance and repair activities of a system whose design you do not have a good command of, efficiently and safely. Aircraft engineering has been intensively supported by "Maintenance Engineering", which offers common scientific methods for many sectors, and this integration has evolved into "Aircraft Maintenance Engineering". Aircraft engineering has been heavily influenced by "Mechanical Engineering", especially in the design and maintenance of landing gear, hydraulic, pneumatic and fuel systems and support components. Since aircraft engineering is a branch of science derived from mechanical engineering, this integration is easily achieved in aircraft and aircraft support components. Of course, the intensive input of electrical and electronic systems (Avionics) in aircraft and weapon systems necessitated an intensive integration with "Electrical Engineering" and "Electronic Engineering" in the design and maintenance of aircraft. The systems that manage the operation of many systems on the aircraft (e.g. mission computer, fire control computer, etc.) are also systems designed with the discipline of "Computer Engineering" and have a close working relationship with both electrical and electronic engineering. "Metallurgical and Materials Engineering" also makes a significant contribution to the "Non-Destructive Testing" of polymer matrix composite and metal materials that make up aircraft structural systems. In Aircraft Maintenance Management; quality, reliability, planning, execution, coordination, supervision, human factors engineering (ergonomics) have always existed and developed according to the conjuncture, in this context; "Industrial Engineering" and "Systems Engineering" derived from industrial engineering have had and will have great inputs and contributions in the management of the aircraft maintenance system. Since the Aircraft Maintenance Engineering model includes many inputs such as intangible (software) & tangible (hardware), environmental (Environment), human as an individual (Liveware-1) and human as a group (Liveware-2) (we call it the SHELL Model); it has benefited and will benefit intensively from the sciences of "Management and Organization", "Psychology" and "Sociology". The necessity to make use of these social sciences in addition to the sciences elevates aircraft maintenance engineering to the concept and model of "Aviation/Aircraft Maintenance Management".

As summarized above; Aircraft Maintenance Management, as a multidisciplinary managerial concept, makes extensive use of both science and social sciences. This interaction has led to the creation of specific technical and managerial models. For example, HFIM (Human Factors in Maintenace), 12 Dirty Habits/12 Dozen in Aircraft Maintenance, SHELL Model, RCM (Reliability Centered Maintenace), etc. Obviously, there are many business models created by the accumulation of knowledge and skills in aircraft maintenance and offered to the service of other sectors. We will briefly discuss the details of these in the following sections.

A. Science Disciplines with Inputs in the Aircraft Maintenance System:

1. Aircraft Engineering

Aircraft engineering is the branch of engineering that deals with the design, development, production, testing, maintenance and repair of vehicles, stationary objects and devices that interact with the air, and the management of all these processes. In short, aircraft engineering is the flagship of aircraft maintenance engineering.

2. Electrical and Electronics Engineering

Electrical Engineering or Electrical and Electronics Engineering is a comprehensive engineering discipline that studies electricity, electronics and electromagnetism and deals with the design and development of various hardware and systems using them. Since the 19th century, it has emerged as a separate discipline with the production, distribution and large-scale use of telephone, telegraph, electrical energy. In the 20th century, it became a more comprehensive discipline with the development of semiconductor technology, the invention of the transistor, the development of microprocessors and computers.

In airplanes; both airframe systems (structural, hydraulic, pneumatic, fuel, landing gear) and engine systems and avionic systems must receive energy from the electrical system and be in a relationship. Similarly, aircraft avionics, radar and navigation systems within the scope of electronics, mission computers within the scope of computer engineering, firing systems within the scope of aircraft engineering, etc. are systems that emerge from the basis of electronic engineering.

3. Computer Engineering

It deals with the design and manufacture of computer hardware and software with the help of electrical systems. 

Many systems of today's aircraft (4th generation and later) are managed by mission control computers.

4. Mechanical Engineering

Mechanical engineering is a branch of engineering that combines the principles of engineering physics and engineering mathematics with materials science to design, analyze, manufacture and maintain mechanical systems. Mechanical engineering requires an understanding of fundamental areas including mechanics, dynamics, thermodynamics, materials science, structural analysis and electricity.

Sub-branches of Mechanical Engineering related to Aircraft Maintenance;

b. Manufacturing Engineering deals with the R&D of tools, machines, processes and systems and various production techniques.

c. Vehicle Engineering is a sub-branch of mechanical engineering;

i. Automotive Engineering deals with vehicles such as bicycles, motorcycles, automobiles, buses and trucks.

ii. Naval Engineering deals with the design and manufacture of marine vessels.

iii. Aerospace Engineering deals with airplanes, helicopters, drones and space vehicles.

iv. Marine Technology Engineering deals with the design of ships and watercraft and the execution of oceanography projects.

As mentioned in Chapter 2, since aircraft engineering is derived from mechanical engineering, mechanical engineers can support areas where aircraft maintenance engineers are in short supply.  In addition, mechanical engineers can easily transition to maintenance engineering.

Airframe systems on the aircraft can also be supported by mechanical engineering disciplines. However, contrary to popular belief, "Gas Turbine Engines (Turbojet, Turbofan, Turboprop, Turboshaft and Ramjet) are unique and belong to aircraft engineering. Mechanical engineering covers internal combustion engines. Therefore, mechanical engineers who will support aircraft engineers need additional training in gas turbine engines.

d. Mechatronics Engineering

It is a mix of mechanical and electrical engineering and deals with the design and study of automation systems. Robotics, Instrumentation, Avionics supports the design of electronics and systems for use in an aircraft or spacecraft. Aircraft systems have important inputs, especially in the design phase. However, this discipline is also utilized in the maintenance, repair and sustainment phases.

5. Metallurgical and Materials Engineering

Metallurgical and Materials Engineering is a multidisciplinary branch of science and technology that today spans the fields of chemistry, machinery, construction, aerospace, electrical-electronics, environment and medicine. It has critical and valuable inputs especially in the design, manufacturing, testing and development phases of aircraft. This influence also manifests itself in the continuous use and decommissioning of aircraft and aircraft systems.

Aircraft structural and airframe, mechanical and avionic systems contain a wide variety of materials. These materials are subjected to deformation by various factors. The presence or absence of deformation on the material is determined by "Non-Destructive Testing" and other techniques of Metallurgical and Materials Engineering. These and similar "methodology" techniques provided by Metallurgical and Materials Engineering make valuable and useful contributions to the aircraft maintenance discipline in the maintenance and sustainment phase. 

5. Industrial Engineering

It aims at the appropriate analysis and design of resources.  In this context, it deals with the application of management, design and technical skills to the design and integration of systems, the design of new products, the development of manufacturing processes, and the design, planning and implementation of the technical functions and/or physical/technical functions of an organization or firm.

Industrial engineering programs typically cover basic engineering principles, project management, industrial processes, production and operations management, systems integration and control, quality control and statistics.

Subfields of Industrial Engineering

a. Engineering Management

Engineering Management is a multidisciplinary field concerned with the application of engineering principles to business and organizational practices. Engineering Management is a profession that combines the technological problem-solving skills of engineering and the organizational, managerial and planning skills of management to take complex businesses from idea to result. Engineering management utilizes the techniques and tools of Industrial Engineering/Systems Engineering. In engineering management, those in the hierarchy below the manager are the "Technical Contributors": Engineers, Technologists, Technicians and Technicians.

In the maintenance, repair and overhaul of aircraft systems, the science of engineering management, a transdisciplinary management method, is effectively utilized.

i. Systems engineering aims to design, manufacture and maintain complex systems or their sub-systems, taking into account time and cost constraints.

ii. Reliability engineering ensures that a vital system behaves as it should, even when parts fail.

In this context, the disciplines of Industrial, Systems and Reliability Engineering have a great deal of input and support, especially in the areas of maintenance and repair planning of aircraft and support systems, system safety analysis and synthesis, reliability analysis and monitoring of aircraft systems and subcomponents, total quality management, execution of ISC (Statistical Process Control) techniques, facility design and layout, human factors engineering (ergonomics), project management, etc.

6. Management Engineering

Business engineering is a program in which business and engineering courses are taken together. It aims to train managers with an engineering perspective. Business engineering is an engineering discipline that focuses on the design and development of businesses as a whole. It can be confused with industrial engineering. Aircraft maintenance management prefers to utilize mainly industrial engineering disciplines in such areas, but also utilizes mathematical and statistical models of business engineering in areas such as human resource management, purchasing management and similar fields of activity.

7. Maintenance Engineering

Maintenance Engineering is the discipline and profession of applying engineering concepts for the optimization of equipment, procedures and departmental budgets to achieve better maintainability, reliability and equipment availability.

The increasing complexity and importance of maintenance engineering warrants a marked increase in the training of machine operators and maintenance foremen through formal school courses reinforced by informed training by experienced supervisors.

Due to the increasing amount of equipment, systems, machinery and infrastructure, the importance of maintenance and therefore maintenance engineering is increasing. Since the Industrial Revolution, devices, equipment, machines and structures have become increasingly complex, requiring a large number of personnel, professions and related systems to maintain them.

A maintenance engineer must have considerable knowledge of statistics, probability and logistics, as well as the fundamentals of the operation of the equipment and machinery for which he or she is responsible. A maintenance engineer must also have high interpersonal, communication and management skills as well as the ability to make quick decisions.

The maintenance engineering discipline is highly utilized in the mechanical, electrical-electronic, electronics, industrial and civil sectors and this task is carried out by mechanical, electrical-electronic, industrial and civil engineers with additional maintenance engineering training, depending on the sector.

The Aircraft Maintenance Discipline has benefited greatly from maintenance engineering and has developed its own aircraft maintenance engineering discipline.

B. Social Sciences Disciplines with Inputs in Aircraft Maintenance System:

1. Management 

Management is planning, organizing, directing, coordinating and controlling in order to achieve business objectives effectively and efficiently. Management is the sum total of decision-making and implementation processes that can use monetary resources, especially people, equipment, fixtures, raw materials, auxiliary materials and time in harmony with each other, efficiently and effectively in order to achieve certain objectives.  

Aircraft Maintenance System includes the resources mentioned above in the SHELL model, therefore, in order to maintain all these resources, aircraft systems and auxiliary elements in an effective, efficient and safe manner; the science of management is utilized at the maximum level in order to carry out planning, organizing, directing, coordinating and controlling in scientific norms. 

2. Psychology

Psychology has moved away from the view that some individuals are inherently more or less accident-prone, to a position where accident propensity is seen as a temporary condition caused by stress, fatigue, illness, cognitive overload or poor mental state. It is observed that individual psychology comes to the fore in maintenance-related errors. For this reason, the discipline of "Aviation Maintenance Psychology" was born and this discipline has benefited greatly from the science of psychology. L1 of the SHELL model specific to Aircraft Maintenance is related to psychology. The science of psychology is utilized intensively in aircraft maintenance management.

3. Sociology

Sociology, or social science, is the study of society and human interaction. Social research ranges from the relationships between different individuals encountered on the street to global social functioning. Aircraft maintenance organizations are dense communities. Human beings behave differently as individuals and differently as a society. In aircraft maintenance organizations consisting of many different specialized groups, grouping, informal management models, the effects of social behavior on HFIM, etc. are many situations that fall within the science of sociology. L2 of the SHELL model specific to aircraft maintenance is related to sociology. Sociology is also used extensively in aircraft maintenance management. Especially in military aviation maintenance based on strict hierarchy, the solutions of sociology science may be needed more.

Conclusion:

Aircraft Maintenance Discipline, model and profession is a dynamic phenomenon that is influenced and benefited from many disciplines and offers exemplary solution models to these disciplines. The fact that the aircraft in the focus of the profession are flying platforms with complex systems has transformed the aircraft maintenance discipline, which is responsible for the maintenance, repair and lifelong maintenance of these systems, into a large, large and enviable organizational structure that is open to development, extroverted, sharing, cooperation and integration. I recommend young people who have a heart for aviation to choose to become a valuable member of the Aircraft Maintenance Profession. I wish you healthy, safe and enjoyable flights.