Aviation's Key Profession and Sector Aircraft Maintenance - Part: 1

Fundamentals of Aircraft Maintenance

The main actor of aviation is the airplane, which is a very necessary and useful flying platform that carries people and materials in the civilian sector, ammunition, people and materials in the military sector, intercepts enemy aircraft, and destroys enemy targets. Aircraft have high-tech and complex systems for their missions and their movement in three dimensions. It is essential for system and flight safety that these systems are maintained, malfunctions are deactivated and revisions are made with economical, effective and safe methods. Ensuring this system safety belongs to the Aircraft Maintenance Profession, the key discipline of aviation.

In line with my knowledge and experience; I would like to promote the "Aircraft Maintenance Profession", which is the most critical of the aviation professions awaiting our young people, with a series of articles.

When this series is completed and read; I am open to criticism, corrections and suggestions from professionals and young people who are enthusiastic about this profession. Corrections, edits and additions will be made in line with these inputs.

My articles will consist of three parts:

Part I will cover the basic philosophy of Aircraft Maintenance as well as the basic requirements for effective aircraft maintenance management. Part I will conclude with an introduction to the aircraft maintenance organizational structure of a typical air force or airline. 

Part II will consist of my views and evaluations on the training of technicians, technicians, technologists, engineers and managers within the Aircraft Maintenance system, which I believe will be the most valuable and critical part of this article on the discipline and profession of aircraft maintenance.

Part III will summarize the disciplines that the Aircraft Maintenance discipline is influenced by and benefits from. 

A. What is Aircraft Maintenance, what does it mean, why is it necessary?

"The discipline of Aircraft Maintenance is a science because its application depends sooner or later on most of the sciences. The discipline of Aircraft Maintenance is an art, because seemingly identical problems regularly demand different approaches and actions, and some managers, engineers, technologists and technicians show more skill in it than others do or even acquire. The discipline of Aircraft Maintenance is above all a philosophy, because it is a methodology that can be applied intensively and modestly depending on a wide range of variables that often transcend more immediate and obvious solutions."

In the early years of aviation, aircraft maintenance was done "as needed" and aircraft typically required several hours of maintenance for each hour of flight time. Major maintenance activities consisted of periodic overhauls of almost everything in the airplane. Although the airplanes and their systems were initially quite simple, such maintenance became very expensive. With the increasing complexity of airplanes and their systems in the following years, this cost increased accordingly. As airplanes have been developed, the modern approach to aircraft maintenance has become more complex. Aircraft, both military and civilian, are designed, tested and developed for reliability, airworthiness and maintainability during the design, testing and development phases, because you don't design aircraft for maintenance, you design them to fly, and unfortunately, in order to ensure this effective and efficient sortie production, you have to carry out a very effective and efficient aircraft maintenance activity. Although this may seem like a paradox, an aircraft, which is a carrier air platform consisting of airframe, mechanical, electrical, electronic, engine systems and derivatives of these systems, is essential and a detailed maintenance program is developed with each new model aircraft or derivative of an existing model. This initial maintenance program can then be adapted by each user air force or airline to suit the nature of their operations. 

This ensures continuous airworthy operation in all conditions. Supporting this individual commitment are ongoing efforts by manufacturers, air forces, airlines and airspace regulators to improve design and maintenance techniques and keep the aviation industry at the forefront. Of course, such a complex approach to maintenance requires both the development of comprehensive maintenance programs and complex but effective maintenance management.

B. Aircraft Maintenance Technical and Engineering Management:

Properly conducting maintenance activities in an air force or airline requires several disciplines: 

a. Maintenance: The hands-on, "screwdriver, screw, bolt and nut, etc." labor required to perform the physical work, 

b. Engineering: Design, analysis and technical assistance required to support maintenance work,

c. Management: The organization, control and administration of many aspects of the maintenance operation, 

d. Production Planning: Planning concepts and organizational activity to effectively support maintenance to plan all necessary work, 

e. Logistics: Understand realistic, futuristic, aircraft inventory coverage to meet the continuous demand for parts required for a successful maintenance operation,

f. Technical Training: To effectively meet the demands of all required maintenance training.

My series of articles on Aircraft Maintenance will be a bit unique; it will cover all these topics (maintenance, engineering, management), but in a slightly different way than theoretical and academic methods, we will look at the "big picture" based on applications, experience and observations. In other words, we will look at the multiple disciplines of "Maintenance, Engineering and Management" in aircraft maintenance as an integrated whole. We will examine how all these disciplines combine and coordinate to achieve the goals and objectives of Air Power and Airline aircraft maintenance. While some details of these three topics are beyond the scope of the discussion, the articles will emphasize the coordination of these three disciplines necessary to achieve the desired results.

These articles are written to share our knowledge and experience with our colleagues who have knowledge and experience in aviation maintenance and who work in maintenance and engineering activities of air forces and airlines; Line, Base and Factory level maintenance in military aviation, Line Level A, B maintenance in civil airlines, Base/Heavy Maintenance level C, D maintenance, lower, middle and senior management positions and who determine their professional career development according to these levels. Those who do not have the technical background in aircraft maintenance organizations can also benefit from our articles by expanding their horizons into the technical field. In addition, young technicians and engineers who wish to pursue a career in maintenance management will learn what our nearly three decades of professional knowledge and experience have highlighted about the general functioning of the maintenance and engineering discipline. Of course, it is not possible in a series of articles to give a thorough explanation of the huge and constantly evolving aircraft maintenance discipline, but if I can write articles that are as full of content as possible, but at the same time simple and fluent, I believe that I can serve my purpose.

"Aircraft" is at the center of aviation, and the aviation world has an interactive group of people, namely aircraft maintainers, who are determined to make aviation a safe, efficient and enjoyable activity around aircraft and aircraft systems. Of course, pilots and many other professional disciplines and groups contribute to the safety of general aviation, but we will not talk about flight safety or aviation safety, but about "aircraft systems safety" and the effects and contributions of aircraft systems safety to aviation safety. 

Aircraft manufacturers, manufacturers of equipment and systems built into the aircraft platform, air forces, airline operators, industry trade associations, regulatory authorities, flight crews and maintenance personnel work together to ensure aviation safety in the design of aircraft and systems through the development of maintenance programs and modifications, and continue their work throughout the life of the aircraft.

Working together and integrated, providing feedback at all levels and in all directions between groups and departments within the profession and the organization, enables the aircraft maintenance industry to deliver continuously improved systems and services to the public. The world of aircraft maintenance has been practicing this concept of "continuous quality improvement" long before the slogan became popular, meaning that the military and civil aircraft maintenance discipline and profession were among the first practitioners of "Total Quality Management".

C. Why should we maintain airplanes?

Why should we maintain airplanes? It's simple: "Maintenance of an airplane provides assurance of flight safety, reliability and airworthiness." The aircraft maintenance department is responsible for performing all maintenance tasks according to the aircraft manufacturer and company requirements. The goal is a safe, reliable and airworthy aircraft.

The aircraft maintenance department provides maintenance and preventive maintenance that translates into aircraft availability/availability to ensure reliability. These functions do not prevent random failure or deterioration of any part or system, but routine maintenance and checks will prevent them from happening and keep the aircraft in good flying condition.

D. Evaluation of Aircraft Maintenance Organizational Structures:

Aircraft maintenance organizations have changed many times over the years, especially in the last seventy-odd years after the jet age, both in military and civil aviation. Centralized and decentralized organizational strategies have been tried many times. Whatever the structure of the organization in which they operate, aircraft maintainers find a way to make it functional. However, organizational structures can limit or enhance performance. Over the last half century, the world's air forces and airlines have experimented with a range of organizational structures for aircraft maintenance in an effort to achieve performance and efficiency. These organizational structures will change and evolve with the changing times. The only constant is change.

Aircraft maintenance organizational structures in both air forces and airlines change due to tactics and strategies based on the current situation, costs, operational requirements, threats and competition. Reorganization of aircraft maintenance organizations has been the preferred method of dealing with staff shortages, low experience levels or lack of performance. The tendency has been to decentralize maintenance when experienced technicians are available, thus bringing it closer to its main customer, the operating fleet, and more efficient on the forward line. However, when there was a dramatic increase in the size of the maintenance workforce, staff costs increased or skill levels declined, the maintenance complex was centralized in a functional structure. In general, while concentrating on the forward lines, i.e. flight lines, and autonomizing the maintenance organization is the preferred method of the air force, deploying a limited number of personnel on the flight lines, performing only pre, inter and post-flight maintenance, and performing comprehensive and major maintenance activities centrally in MRO (Maintenance, Repair and Overhaul) centers on the reverse lines is the preferred structure of civil airline carriers, but preferences may vary depending on the needs.

The essence of any air force is its ability to produce combat aircraft sorties. Inoperable aircraft and poor maintenance practices directly affect the availability of aircraft required for the mission, in other words, air power. The same is true for civilian airlines. In line with the activity rate of the existing aircraft inventory, sufficient sorties can be produced and the company earns money.

Centralized Maintenance Organization structure is generally preferred in Civil Aviation Maintenance. A limited number of personnel and equipment are maintained on the flight lines. While minor maintenance and transit maintenance are performed on the flight lines, major maintenance and overhauls are performed at the MRO (Maintenance Repair and Overhaul) centers in the background. The centralized maintenance system is the most efficient and economical system. It is the most suitable and economical model for civil airline transport aircraft, which do not have as many systems as fighter aircraft and have a very high activity rate.

As an organizational structure in Military Aviation Maintenance, especially in Jet Fighter Aircraft Maintenance organizations;

Central Maintenance System

Most NATO Air Forces prefer this aircraft maintenance organization. Some have created semi-centralized, semi-decentralized hybrid maintenance organizations.

POMO (Production Oriented Maintenance Organization) is an organizational structure developed by the Israeli Air Force. It aims to maximize sortie production. Flight lines are heavily staffed with maintenance personnel and equipment. Each flight line carries out maintenance and troubleshooting activities independently from the maintenance workshops in the background. Maintenance planning is centralized. 

COMO (Combat Oriented Maintenance Organization) is a structure created by the US Air Force under the influence of POMO. It is almost equivalent to POMO. However, the flight line maintenance plan is not centralized but semi-centralized by the flight lines. It is practiced by the US Air Force and the Turkish Air Force in NATO.

Conclusion:

Aviation/Aircraft Maintenance discipline is a methodology that plans and executes the maintenance, troubleshooting and overhaul activities of aircraft and their equipment within a complex yet dynamic organizational structure. The Aircraft Maintenance discipline is open to continuous improvement, has skilled personnel with the most advanced level of education in parallel with the aircraft as its focus, is efficiency and system safety oriented, and is the key profession of the aviation industry in terms of system safety.