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An Empirical Study to Determine the Maintenance Cost Drivers of Ageing Aircraft for Enhancement Engineering Management

Chapter One: Overall Research Questions


Ageing is a natural process of change in all aspects of existence, it applies to all living or non-living matters. Depending on prevailing conditions, the changes may occur through a normal or accelerated process of transformation from its original form into a new existence.

This means that the outcome of ageing depends on the change process itself. Imagine, the impact of a healthy or unhealthy lifestyle on human age, fitness, and wellbeing. Aircraft is not indifference to this phenomenon. This argument implies that maintenance is an ongoing and integral process of an aircraft. Controlling this process of change in an informed manner can reduce aircraft ageing effect and its cost impact associated with maintenance activities.

The aviation industry is characterised by strong competition and uncertain situations, it is imperative to have a strategic driven objective to sustain long-term competitive advantage in the industry by focusing on their existing operations where cost impact will be significant over aircraft lifecycle. Until recently data handling activities related to maintenance cost evolution of ageing aircraft have been given little attention. Thus airlines have had less detailed observations on maintenance cost drivers.

Aircraft maintenance is not only planning, scheduling, and performing scheduled and/or unscheduled tasks at a reasonable turnaround time. It also demands simultaneously meeting national and international regulatory requirements while performing maintenance checks.

Importantly such performance needs to ensure that, every departing aircraft is safe, reliable, airworthy, and on-time while maintenance cost of it is kept to the lowest possible. If no means made to exist for a reasonable estimation of maintenance cost evolution throughout aircraft lifecycle, striking an equilibrium between ensuring quality requirements and making maintenance cost the lowest possible remains a challenge for air operators when aircraft ages.

As (Pyles,2005) argued, Aircraft ageing have various parameters that influence maintenance cost these include Flight hours and Flight cycles, Aircraft age, Operating environment, Aircraft type and its Complexity, Purchase price, Scheduled and Unscheduled maintenance, National or international regulatory requirements are some of the cost drivers, in which this research is focused on seeking new insight based on past literature study within the context maintenance management of ageing aircraft.

Background and justification

As aircraft operational lifecycle increases, the requirement for regular and effective maintenance in order to keep the intended operating condition increases (Maclean, Richman, & Hudak, 2018). Maintenance requirement includes both scheduled and unscheduled maintenances.

Thus, an increase in maintenance requirements over aircraft operational lifecycle, in turn, increases maintenance cost (IATA,2018). A number of research conducted in the industry indicates that maintenance cost is constituted a major share in the operational cost of aircraft and operators (IATA, 2018), maintenance alone consumes 20% of aircraft operating cost. (Maple,2001).

The aviation industry which is characterised by high competition and controlling the operational cost and hence maintenance cost is of high importance for airlines to stay competitive while being profitable (Beck & McLoughlin, 2006). Ahmadi (2010) suggested that compared with an aircraft’s operational lifecycle of an aircraft it is easier to estimate the expected cost during the manufacturing phase because the cost drivers are known in this phase.

However, it is difficult to accurately predict the long-term maintenance cost during the operational lifecycle, especially of an ageing aircraft (Baohui, Chunhui, & Yaohua, 2013). In operational lifecycle, the maintenance cost divers can be hidden (Ackert, 2010). The impact of maintenance cost divers could result in significant variation of operational cost, which can reduce the competitiveness and profitability of an airline (Camilleri, 2018).

Therefore, it is necessary to identify maintenance cost divers of ageing aircraft for the effectiveness of maintenance cost budgeting and better controlling maintenance performance (Dixon, 2005). Thus, this research identifies the maintenance cost drivers of ageing aircraft and aims to extend the existing research while filling the literature gap emphasizing maintenance process improvement in the engineering management domain.

Specific Aims and Objectives of the research

This study aims to conduct past literature-based research to find out the main variables of maintenance cost drivers of ageing aircraft in the global airline industry for better aircraft engineering management. To address this, the research aimed at the below-mentioned objectives.

  • Conduct a systematic review of primary and secondary research articles and literature to determine the major maintenance cost drivers of ageing aircraft.
  • Make recommendations regarding the importance of different factors that can influence the maintenance cost of ageing aircraft for better engineering management.

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Significance of the Research

The research is mainly focused on maintenance cost drivers of ageing aircraft. Therefore, attention is given to identifying major cost drivers directly associated with the management of ageing aircraft maintenance.

As stated earlier maintenance cost generally constitute about 20% of the Operational cost of an airline. Thus, any reduction from ever-increasing maintenance cost cannot be ignored when aircraft ages. Airlines’ decision-maker, particularly those having higher operational costs, would be the area of concern. Moreover, if the cost impact is significant, airlines executive would be more interested in utilizing it as an input for aircraft replacement and/or repair decisions.

Scope of the Research

It has been said that maintenance cost increases with aircraft ages, this increase in cost can be explained as the function of the direct and indirect maintenance process, in which various parameters can also influence this. However, this research focused on identifying aircraft ageing effect on direct maintenance costs and provides the major maintenance cost drivers in the context of maintenance management.

The scope is, therefore, to develop a decision support model which can be helpful for estimation of major direct maintenance cost driver’s evolution throughout aircraft lifecycle with respect to the management of ageing aircraft maintenance.

Rationale of the Research

Aircraft maintenance is considered as highly dynamic and regulated industry characterised by interdependent and complex along with the interdependent system and technologies that are detailed as well as legally binding procedures of task and documentation. It mainly publicises the rate of accidents and highly regulated the management systems for ensuring efficiency, reliability and safety at all times.

It is added that task analysis has mainly revealed that the activity of aircraft maintenance is complex as it is a socio-technical system that required sustained coordination, cooperation and communication among different workgroups as well as teams in which aircraft maintenance engineers are included along with crew managers, hangar and inspector, various subsystems like commercial and planning, quality and engineering and external bodies like manufacturers and regulators.

This shows that there is great importance for maintenance cost drivers for ageing aircraft for enhancing aircraft management which is important for enhancing age for aircraft (Fouladi et al., 2020). It is analysed that very few researches have been conducted to cover the maintenance cost drivers for ageing aircraft to enhance the engineering management.

Most of the researches are mainly related to engineering management in which cost drivers are not mentioned, whereas most of the researches are not focused over aircraft management. That is why this research has been conducted to analyse the cost drivers that affect aircraft ageing.

Expected Outcome and Limitation

Employing thematic analysis method based on the collective evidence of various past studies and literature(Periyarselvam, Tamilselvan, Thilakan, & Shanmugaraja, 2013; Gerdes, Scholz, Galar, Gerdes, & Scholz, 2016; Bugaj et al., 2019; Mofokenga et al., 2020), The major maintenance cost drivers which are directly associated to ageing aircraft maintenance management as function aircraft age, flight hours, maintenance program, regulatory requirements, dispatch reliability, and operational environment are determined. Accordingly, their impact on cost and maintenance processes improvement are described.

The major limitation of this study is that it is based on the review of primary data such as journal articles, information available on a good website, industry newspaper, and academic sources. But no data in the form of questionnaires and/or interviews have been collected and used so that the research is unable to uncover the underlying issues that are specific to airline maintenance and engineering employed processes and indicate an effect of a customized maintenance program as aircraft ages.

Thus the research outcome is strictly limited to the information available in the readily available sources of primary data. Moreover, due to the limitation of time and resources, the research is limited to include the impact of other parameters such as flight cycle, aircraft type and complexity, and technological advancement on aircraft.

Chapter Two: Literature Review


This section briefly reviews the past literature related to maintenance cost drivers of ageing aircraft. It was found that various studies have been conducted in the past to evaluate the maintenance cost drivers of aircraft in the global airline industry such as; Chen (2010), Yi-yong, Li-ping and Kai (2002), Yang and Yang (2012), Rzevski, Knezevic, Skobelev, Borgest and Lakhin (2016), Stadnicka, Arkhipov, Battaïaand Ratnayake (2017), Pogačnik, Duhovnik and Tavčar (2017), Guzhva, Raghavan and D’Agostino (2018).

Bugaj, Urminský, Rostáš and Pecho (2019) found the following variables to have an impact on maintenance cost of aircraft such as Flight environment, Flight Hours & Flight Cycles, adopted Maintenance Program, Special Conditions, Maintenance Practices, Type of aircraft, and etc.

While studying the military aircrafts Pyles, (2003) argued that the age of aircraft to have a significant positive impact on the maintenance cost. As aircraft age increases in the newness and ageing period, its cost of maintenance becomes higher (Dixon, 2005). Similar findings were found by other studies such as Mofokenga, Mativengaab and Marnewicka (2020), where the researchers found flight hours to have a positive impact on maintenance costs of aircraft.

The aircraft with higher flight hours tend to have high maintenance costs. However, the aircraft types with low dispatch reliability tend to have high maintenance costs. Similarly, (IATA, 2018) suggested that, independently of aircraft utilization, the requirements for the performance of additional tasks that are driven by adopted maintenance program increases with an increase of aircraft age, thus eventually causing an increase in maintenance cost.

Aircraft Ageing

It is analysed that the aircraft begins as soon as it first flies and has different effects over ageing that begun to take place almost immediately. However, the term used can be applied for the issues that start to rise as the time since new is regarded as important and is greater than the average age of the same class aircraft (Prudhomme, 2018).

The process of designing aircraft and its subsequent establishment for the principles for approving maintenance programme has aimed to take full account for the effects of continuously using aircraft (Baohui, Chunhui . and Yaohua, 2013). There is major damage intolerance as well as a safe life.

The philosophies related to design are mainly applied over nowadays, and appropriate methods of inspection and intervals are developed for identification of environmental, accidental or fatigue damage effects. It is considered to be usual for the fatigue that is related to the sampling inspection programme as well as corrosion prevention and control programme which needs to be established (Mofokeng, Mativenga and Marnewick, 2020).

It is analysed from the study conducted by Karadžić, Petković and Šabić, (2012), that keeping older het aircraft in such condition that is airworthy has been considered to present major difficulties that have not all been addressed by the maintenance that is prescribed.

Major serious issues related to airworthiness have been raised in different ageing aircraft, which have often been considered as the direct consequence for filling gap among former and current practices that are needed for aircraft issues of certificate and maintenance programme approval.

Factors affecting Aircraft ageing

It has been investigated from some recent studies that several major issues have been raised from the aircraft age which has not been recognised nor addressed until the fatal accidents took place. Recently, there are general principles for the system deterioration that affects the old aircraft that are receiving the attention that is renewed.

It is evaluated that the United States has seen most examples of accidents that have been attributed to the problem of aircraft ageing. It took place mainly in order to co-ordinate the development of the solutions for risk management for different types of problem-related to the ageing of aircraft, particularly with the structures (Bugaj, 2019). Several factors affect the ageing of the aircraft which is discussed as follows:

Chronological age

Aircraft are known as the assembled and engineered devices that mainly uses strict standards that are based on many scientific laws as well as principles of mechanical engineering. It mainly forms a base for the ways by which aircraft would perform as well as the maintenance that is required.

It is not necessary that all the materials, as well as assemblies, wear the same rate as well as they have the same fatigue limits (Morgan, 2020). Every part should be logged as well as recorded in order to ensure the safety inspection properly along with this there are repairs which are carried out as per operations of manufacturers manually (Le and Lappas, 2015).

It mainly means that the engineers should have to come up with the series for different inspections intervals, which helps determine when components and parts should be replaced and repaired. The aeroplane owners want to track the status and manage the downtime, which plans for eventual replacement and sale.

However, several components have time limits that should be replaced at the interval of time that is regardless of the number of hours by which aircraft have flown which relies on the chronological time (Kourousis et al., 2013) on. In other cases, the mechanical duty cycles and TTAF dictate the maximum life span for complete aircraft. This is mainly due to the main components like the main wing spar reaching the engineered limits and costs for replacing the exceeds with the aeroplane’s value.

Number of flight cycles

The flight cycles are mainly defined as the operation of the engine from the time an aircraft leaves the ground until it mainly touches the ground at the end of the flight. It is regarded as the main purposes for agreeing on the abroad which takes off or touches and go landing which should be considered as the flight cycle (Prudhomme, 2018).

There are flight cycles that are mainly pressurized aircraft like commercial airliners, which are considered as the number of times the door has been closed along with the fuselage which has been pressurized (Vega, Pamplona and Oliveira, 2016). The flights take 5 hours or 10 hours, regarded as the 1 cycle of flight. It mainly gets recorded in the airframe which covers log book.

Number of Flight Hours

According to the research of MacLean et al., (2018), a noticeable impact of the flight hours has been observed on the aircraft ageing. It has been further evaluated that structural fatigue is observed because of the high number of flight hours. The possibility of structural fatigue can be observed from any origin.

This includes the advent of pressurized aircraft where different issues are determined in the aircraft design and the aircraft is used for the long-flight hours, which significantly reduces the life of the aircraft. However, this cause aircraft ageing, and it also results to have low-probability of the aircraft stability because the aircraft is being used other than its approved life.

On the other hand, the long flight hours also cause corrosion by which chronological age is observed, and an exponential increase in corrosion over time is also observed. This is because of the long flight hours and an adverse impact on the aircraft components is also observed because they are being utilized more than their strength.

The long flight hours beside the aircraft ageing, it also reduces the life of the aircraft, which results negatively for the airline because they have to face several risks if they are not having appropriate monitoring system to monitor the time for flight hours for their aircraft, which will result in aircraft ageing.

Furthermore, the long flight hours also cause fatigue to the aircraft wings along with this, the pressurized sections of the aircraft are also affected, resulting to have high risks and low aircraft performance. The number of flight hours causes structural fatigue, which significantly increases the probability of aircraft ageing.

On the other hand, the design of the aircraft is also an important factor based on the number of flight hours. The aircraft manufacturers are required to ensure that the appropriate design is being developed and all the components that have been placed within the aircraft design are sufficient, which will ensure that the aircraft has the capability of long-flight hours. The design flaws also impact aircraft efficiency, and the aircrafts doing the long flight hours result in aircraft ageing (Tavares and De Castro, 2017).

On the other hand, it has been evaluated that fatigue has been determined as the most highlighted element, which causes aircraft ageing and is observed because of long flight hours and low aircraft maintenance. The aircraft during their operation has to suffer from different rates of fatigue because of the aircraft structure and the load being bearded by the aircraft. The high number of flight hours cause significant impact on the aircraft structure by which the aircraft ageing is observed (Tavares and De Castro, 2017).

Parameters for measuring Aircraft Ageing

There are several aircraft designs capable of safe and useful operations in the current environment that possess manufacturers that have gone way out of the business for reasons that no longer exist. There are several other manufacturers that stills do not have a capability for providing the field support in order to provide ageing models.

It mainly includes the engineering drawings, as well as procedures of maintenance and other technical data which is not available from these things that are non-existent or supportive manufacturers (Saltoğlu, Humaira and İnalhan, 2016). It mainly acquired, organises, preserves, and makes available the easy access for the data, which can be considered great to enhance the likelihood for the improvements in order to maintain and operate safely for specific aeroplanes (Crowe et al., 2019).

The models are extended and possess different model types whose actions can have a major impact on the safe operation in the future, which is among the ageing of small aeroplane fleet. There are two particular practices which have a fundamental impact over the way maintenance and an inspection can be approached to align the aeroplanes.

it included the record research of the aeroplane as well as special attention of the inspections that are doing either for these that help assesses the conditions for an aeroplane (Kurnyta, 2020). However, if both are being done throughout the effects of ageing over the aeroplane, it also provides a method that helps monitor the conditions that continue to age.

Chapter Summary

This chapter has defined the review of the literature addressing different aspects associated with aircraft ageing. In the first section of this chapter, different factors of aircraft, ageing has been defined. Furthermore, this chapter has also defined the different factors causing aircraft ageing along with this, the parameters are addressed by which the aircraft ageing can be determined and different factors can be identified, which defines the detailed information regarding aircraft ageing.

Chapter Three: Methodology

Description of Methodology

This research will be conducted by collecting primary and secondary data. The primary data in the form of empirical literature found in journal article and research paper will be collected, secondary data in the form of (past literature) information available on the trusted website and dependable newspaper will be collected.

The primary data will be gathered from the Journal article and research paper; however, no primary data will be collected via questionnaire or interviews. The reason to which no primary data via questionnaires or interviews is being used is due to anticipated difficulty in obtaining informed consent from participants required to fulfil the ethical consideration in compliance with data gathering and analysis within the limited timeframe.

Besides, it is also assumed to be infeasible to conduct primary data-based research due to COVID-19 restrictions, as most of the respondents cannot be approached to explain the research purpose and collect data from them in the form of interviews or questionnaires.

The secondary data in the form of literature will be collected from various sources, which include published online journals, academic books, websites and online resources of business organizations, newspapers, magazines, and records and publications of business organizations related to diversity in the workplace. However, while collecting information from online secondary sources of data, it will be ensured that only authentic and valid information which can be considered reliable is obtained.

The systematic review will be conducted using thematic analysis where the collected information will be logically structured, summarized, analysed, and discussed (Collis & Hussey, 2009). Moreover, a thematic analysis will be used to identify similar findings (themes) and bring together the evidence found in the past research regarding the maintenance cost drivers/factors of ageing aircraft (Sekram & Bougie,2016).

Chapter Introduction

The chapter inclined towards providing a detailed methodological design that the researcher has followed. The chapter is divided into multiple sections, each oriented towards a particular aspect of the study. The initial sections propose a paradigm and approach of the study, whereas the further sections focus on providing the chosen data collection method and the data analysis technique. The chapter also includes the strengths and weaknesses of the chosen methodology.

Research Paradigm

Faith or belief under which the study is carried out is known as a paradigm of the research. It is also regarded as the philosophy of the research. Positivism is when the natural phenomenon is being studied, whereas in interpretivism human differences are appreciated (Mauthner, 2020).

However, the researcher has used interpretivism as the philosophy of the research. The main reason to select this philosophy is that it is straightforward. It has helped the researcher easily get the information that is wanted. It has made it easy for the researcher to develop a thought or view regarding different cost-effective barriers in the airline industry. The philosophy of interpretivism has promoted the difference in opinions.

Research Approach

The direction towards which the study is being carried is known as the approach of the research. Inductive and deductive are two commonly adopted approaches. The deductive approach is basically when any theory is being tested in the study whereas inductive approach is oriented towards the generation of an entirely new theory (Qizi, 2020).

However, the researcher has used an inductive approach because previous data have been used to formulate a new theory. An inductive approach is the most suitable approach when it comes to qualitative data. In this research, the researcher has induced data from already existing journals, research and other previous secondary sources which are qualitative in nature.

Research Strategy

Case study and surveys are the two strategies that are used when conducting any research. The researcher for this study has used a case study because the information has been gathered from secondary sources. Surveys could have been used as a strategy only if the researcher would have used primary data collection method. However, the researcher has used previous data and studied that data as a case. The previous research and interviews in the study cannot be regarded as the survey of the study but a case which has been studied in the study by the researcher.

Data Collection Method

Methods or ways that researchers adopt in order to gather data are known as data collection methods. Primary and secondary are two commonly used data collection methods. Primary data is also regarded as first-hand information. The researcher selects participants and gathers data directly from participants. On the other hand, secondary data is when the researcher gathers data from sources already available in research papers or on the internet (Baker, 2020).

Primary data is regarded as more authentic than secondary data primarily because of the direct interaction of the researcher with participants. However, primary data requires a lot of time and is not suitable for research where time is a major constraint. This has been the major reason why the researcher has used secondary data in order to collect data.

The researcher has ensured the element of authenticity by selecting journals or articles where the previous researcher has used primary data collection as the data collection method for their study. The researcher has also sorted out and classified previous researches when selecting for this study.

The researcher has selected researches having primary data collection method along with interviews. This has been done in order to get detailed insights from aircraft engineers regarding maintenance cost drivers in the airline industry. The researcher has also included secondary data primarily for developing literature based on the previous research conducted in the same regard. The inclusion of secondary data has not been limited to research papers, websites, academic books and other related online resources.

Ethics have always been integral to research (Pennings, 2020). It is the responsibility of the researcher to inculcate ethics in every aspect of the study, irrespective of the design that has been followed for the study. The researcher for this study has made ethics an utmost priority. For this purpose, the researcher has used only authentic sources or journals to extract secondary information. The researcher has also tried to avoid manipulation or exaggeration when analysing the collected data.

Data Analysis

Data analysis is one of the most important parts of the research. The prime reason is that the collected data is analysed using an applicable tool or technique (Munch 2017). The researcher for this study has used thematic analysis primarily because interviews from different journals and studies are analysed.

Thematic analysis has helped the researcher evaluate different types of cost-effective drivers from the perspective of different aircraft engineers along with other technical people. It has been chosen because it is a technique which is highly flexible. It also makes the explanation easy for the researcher to write and read to understand.

The reader does not get confused with complex terms and abrupt formation (Terry et al, 2017). Thematic analysis has helped the researcher cater to different sub-topics in separate sections. For instance, aircraft ageing and its factors have been investigated in the first theme whereas aircraft ageing and its factors have been analysed in the second theme. Thirdly, parameters of measuring aircraft ageing have been investigated in the third theme.

Strengths of the Methodology

Consideration of ethics in every aspect of the method can be regarded as one of the biggest strength of the methodology because there are many types of research where the researcher usually compromise on ethics either in the phase of collecting data or when analysing the same collected data.

Another strength of the research is that the researcher has effectively managed to work in tough times of the pandemic. The researcher has found an effective alternative for not being able to collect data from interviews. Besides that, the researcher has efficiently catered the limitation of time and budget efficiently.

Weaknesses of the Methodology

The major weakness of the research is that the researcher was unable to gather primary data directly by selecting and interviewing participants directly. The pandemic and the lockdown situation has made it nearly impossible for the researcher to go for the primary data collection method (Kumar et al, 2020).

However, this issue was much more effectively catered by the researcher by using previous journals or papers where the interviews have been conducted in the same regard. The researcher realises that it was the need of the time and not the most suitable data collection method to follow. The main reason for this is because new knowledge or updated information from participants have not been extracted, which could have been possible in the primary data collection method.

Chapter Summary

This chapter has addressed the methods that have been used in this study. In this chapter, the research approaches have been defined along with the methods used for data collection and analysis utilised within this study. Moreover, the strength and weaknesses of the adopted methods have also been discussed, which defines the aspects by which these methods have been adopted within this study.

Chapter Four: Data Analysis and Findings

Investigation of Aircraft Ageing and Its Factors

According to the research of Wang et al., (2013), different factors have been determined that cause aircraft ageing. The first factor identified for aircraft ageing is chronological age. This factor defines the length of time since the aircraft have been manufactured or the components that are installed within the aircraft.

However, the chronological age is also referred to as the calendar age. Furthermore, MIKALAUSKAITĖ and DAUKANTIENĖ (2020) have further defined two distinct factors associated with aircraft ageing. The first factor is associated with the flight hours and flight cycles that have been performed by an aircraft. The second factor includes the age-related factors, which includes corrosion, deterioration and fatigue. During the interview process from a respondent regarding the factors that cause ageing, and the respondent has described that:

“Airlines that do not maintain the aircraft timely cause ageing”

Based on this, another respondent has further defined that:

“The lack of maintenance team in the process of aircraft inspection after every flight lead towards aircraft ageing”

In relation to this, Wang et al., (2020) has defined that aircraft are designed for a specific lifespan, which is also known as aircraft design life. This allows the designers to ensure that throughout the specified life of the aircraft along with the aircraft structure and the reliability of the operating components.

It has been determined that an aircraft normally has a 20-year lifespan with a specified number of flight cycles and hours. These are the factors by which the aircraft ageing is caused, and serious adverse consequences are obtained in the aircraft performance where maintenance is not done in the desired manner and the components installed within the aircraft does not perform accordingly, which significantly degrades the overall performance of the aircraft.

Furthermore, it has been observed that the aircraft manufacturers evaluate the aircraft type by which the aircraft can withstand use for the design life period. This requires regular maintenance and the operators will have reliable services throughout the aircraft’s design life.

Analysing the Impact of Ageing Aircraft on Aviation Sector

As per the research of Graham et al., (2019), a significant impact of the ageing aircraft on the aviation sector has been analysed. It has been identified that fatigue has been determined as a significant impact on the aircraft ageing, which negatively affects the aircraft use and the aviation sector.

These ageing factors cause serious issues for the aircraft structure because of different structural loads, which severely affects the airline operations and has a negative impact on the aviation sector. However, it has been identified from the answer of a respondent, which defines that:

“Ageing factors results to have serious issues where the airlines do not have the required aircraft to perform the airline operations sufficiently.”

It has been evaluated from the research of Crowe et al., (2019), which defines that the aircraft ageing also produces its impact on the damage tolerance where the aircraft safety is affected adversely, which also results negatively for the aviation sector. However, a respondent has further defined that:

“If the Aircraft damage tolerance is reduced, it degrades the aircraft performance and the aviation sector has to face a negative impact because of this issue.”

It has been evaluated that the ageing aircraft results to have low aircraft reliability and it also requires high maintenance and the airlines have to invest significantly to maintain an aged aircraft, as well as highly technical and experienced resources, are required to perform this operation.

On the other hand, the airlines have to face significant limitations where they cannot use the aircraft on long flights and it also highlights the risk for the passengers because a high probability is observed of aircraft failure because of its low efficiency and the aviation industry is also affected adversely because of this issue. This requires high maintenance by which the issues associated with the aircraft ageing can be addressed accordingly and sustainable aircraft performance will be observed (Tisdall et al., 2020).

Investigating the Parameters of Measuring Aircraft Ageing

In their study, Vinson et al., (2019) has defined various parameters that could be used to evaluate the aircraft ageing. The first parameter identified to measure the aircraft ageing is associated with the level of corrosion observed on the aircraft. It has been evaluated that the corrosion is a time-dependent failure mechanism resulting from the electrochemical or chemical degradation of metal that has been used within the aircraft. Based on this, a respondent has given the response that:

“Airlines that do not timely monitor and maintain the aircraft structure often face this issue, which significantly degrades the overall performance of the aircraft and in some cases the airline has to remove the aircraft to perform further flight operations”

It has been evaluated that Pin et al., (2020), which highlights that the corrosion produces a serious impact on the aircraft structure where the electrical connectors and flight control cables are also affected, and this has been identified as the core parameter by which the aircraft ageing can be evaluated. Significant measures can be induced to overcome this issue.

Another measure identified to evaluate the aircraft ageing is to analyse the structural reliability of the aircraft (Staab and Balle, 2019). Based on this, a respondent has defined that:

“Aircraft ageing cause serious issues for the aircraft structure because it reduces the overall strength of the aircraft”

Staab and Balle (2019) have further defined in their study where the reduction in the structural reliability cause its impact on the aircraft strength where the required efficiency is not obtained, and the airlines can highlight the weak areas to address the issue of reducing structural reliability.

Furthermore, this requires to evaluate perform the aircraft maintenance as per the schedule, which will result to have the long-term performance of the aircraft and the issue associated with aircraft ageing can be addressed in the desired manner. However, this will also result to have vital means where long flight hours for the aircraft will be obtained.

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Chapter 05 Conclusion and Recommendations


This chapter is the concluding chapter of the study as it concludes the complete study. The chapter is mainly divided into two sections in which the first section includes evaluation of the findings of the data whereas the second section covers the recommendation, managerial implications as well as a future research direction.

Evaluation of the key findings

The main aim of the study is to determine the maintenance cost drivers for the ageing of aircraft in order to enhance the engineering management. The study has been conducted by following secondary qualitative method. This study is mainly conducted as a systematic review in which primary and secondary data is included in the form of research articles and literature in order to determine the main maintenance cost drivers for ageing the aircraft.

The study also includes the section in which the importance of different factors that can influence the maintenance cost of ageing aircraft for better engineering management. It is concluded that the process of designing aircraft as well as its subsequent establishment for the principles for approving maintenance programme has aimed for taking full account for the effects of continuously using aircraft.

There is major damage intolerance as well as a safe life. The main factor that affects the aircraft ageing includes chronological age as well as the number of flights cycles. The analysis of the study shows that mainly means that the engineers should have to come up with the series for different intervals for inspections, which helps determine when components and parts should be replaced and repaired.

It is regarded as the main purposes for agreeing on the abroad which takes off or touches and go landing which should be considered as the flight cycle. it is also concluded that ageing does not have such implication for the patterns of air travel as well as the organisation of air transport system but it has major impacts over the workforce of different stakeholder in the industry.


The recommendations for the importance of different factors that can influence the maintenance cost of ageing aircraft for better engineering management are as follows:

It is recommended that maintenance may be driven by the hours of flights, calendar age as well as cycle time which is considered to be the same as changes in automobiles that are recommended to be changed after some specified time. It is recommended that the changes should take place after 3 months in which the number of hours among the scheduled maintenance would vary as per the fleet. Such fleets flying over short routes regularly ages differently compared to the fleets on a regular fly route. There are expensive events of maintenance which is caused fir to the number of cycles as compared to hours spent in the flight.

It is recommended that the aircraft systems engineering department should mainly review the standard data package for the applicability of the fleet, which further verifies that local standard of regulatory as well as the technical requirement of airlines should have been satisfied.

In case the review shows that the parts are not acceptable, it is important for the engineering department to issue an engineering authorisation for using parts which initiated the important changes in the documents that the maintenance can use. In case reviews are identified in the issues, the candidate should become a part of being rejected or supplier should request for providing the additional documentation.

It is further recommended that the financing and purchasing department should identify the opportunity for using a particular part which is mainly performed the analysis of important things that shows the case of business as well as it assembles a proper standard package by which documentation from the prospective supplier can be used.

Further Research Directions

It is evaluated that the study has been mainly conducted by following a qualitative research design in which the data has been collected from previously conducted research. For the future research quantitative research method can be used, or for qualitative research method primary method of data collection can be used to get distinct results.

The research is mainly focused on over-analysis of maintenance cost drivers for ageing aircraft to enhance the engineering management as cost drivers are mainly focused on the study. For future research, other drivers can be focused in order to contribute to the field of literature. The research is not region-specific, so in order to get specified results, it is recommended that some particular sector or airline can be selected to conduct the study, which helps in getting particular results.

Chapter Five: Reference and Appendix


Ackert, S.P. (2010). Basics of Aircraft Maintenance Programs for Financiers: Evaluation & Insights of Commercial Aircraft Maintenance Programs. 1-23. Online;
Baker, L., 2020. Data collection. Lee Baker.

Baohui, J., Chunhui, X. and Yaohua, L., 2013. Study on Optimization Method of Aircraft Maintenance Plan Based on Longest Path. JApSc, 13(16), pp.3354-3357.

Baohui, J., Chunhui, X., and Yaohua, L. (2013). Study on Optimization Method of Aircraft Maintenance Plan Based on Longest Path. Journal of Applied Sciences, 13(16), 3354-3357.

Beck, J. and McLoughlin, B. (2006). Boeing – AeroMagazine Maintenance Program Enhancements, Qtr 04, 24-27.
Bryman, A., & Bell, E. (2015). Business research methods. Oxford University Press, USA.

Bugaj, M., Urminský, T., Rostáš, J. and Pecho, P., 2019. Aircraft maintenance reserves–new optimization approach. Transportation Research Procedia, 43, pp.31-40.

Bugaj, M., Urminský, T., Rostáš, J., and Pecho, P. (2019). Aircraft maintenance reserves – new optimization approach. Transportation Research Procedia, 43(2019), 31–40. Online;

Camilleri, A. (2018). Aircraft Operating Cost and Profitability. Travel Marketing, Tourism Economics and the Airline Product: An Introduction to Theory and Practice. Springer International Publishing.

Chen, W.J. (2010). Methodology and theory: minimizing completion time with maintenance schedule in a manufacturing system. Journal of Quality in Maintenance Engineering, 16(4), 382-394.

Collis, J., & Hussey, R. (2009). Business Research: A Practical Guide for Undergraduate and Postgraduate Students. Palgrave Macmillan.

Crowe, C.R., Formosa, R., Sanders, C. and Thomas, D., 2019. Asset management of an ageing aircraft opportunities lost and wins achieved. In AIAC18: 18th Australian International Aerospace Congress (2019): HUMS-11th Defence Science and Technology (DST) International Conference on Health and Usage Monitoring (HUMS 2019): ISSFD-27th International Symposium on Space Flight Dynamics (ISSFD) (p. 307). Engineers Australia, Royal Aeronautical Society..

Crowe, Colonel R., R. Formosa, C. Sanders, and D. Thomas. 2019. “Asset management of an ageing aircraft opportunities lost and wins achieved.” In AIAC18: 18th Australian International Aerospace Congress (2019): HUMS-11th Defence Science and Technology (DST) International Conference on Health and Usage Monitoring (HUMS 2019): ISSFD-27th International Symposium on Space Flight Dynamics (ISSFD), p. 307. Engineers Australia, Royal Aeronautical Society.,.

Dixon, C. M. (2005). The Costs of Aging Aircraft Insights from Commercial Aviation. RAND Dissertation. Online;

Fouladi, E., Shadaab, N., Abedian, A. and Tanara, A.K., 2020. AGING AIRCRAFT COST ANALYSIS USING SYSTEM DYNAMICS MODELING.

Gerdes, M., Scholz, D., Galar, D., Gerdes, M., and Scholz, D. (2016). Effects of condition-based maintenance on costs caused by unscheduled maintenance of aircraft. Journal of Quality in Maintenance Engineering, 22(4), 394-417.

Graham, A., Budd, L., Ison, S. and Timmis, A., 2019. Airports and ageing passengers: A study of the UK. Research in Transportation Business & Management, 30, p.100380.

Guzhva, V., Raghavan, S., and D’Agostino, D. J. (2018). Principles of maintenance reserve development and management Aircraft Leasing and Financing, Elsevier, 263-298.

IATA (2018). Maintenance Costs for Aging Aircraft 2018, 1st Edition. IATA. Online;

Karadžić, R., Petković, D. and Šabić, M., 2012. A model for the maintenance of old aircraft. Aviation, 16(1), pp.16-24.

Kourousis, K.I., 2013. A holistic approach to general aviation aircraft structural failure prevention in Australia. Aviation, 17(3), pp.98-103.

Kumar, A., Sharma, K., Singh, H., Naugriya, S.G., Gill, S.S. and Buyya, R., 2020. A drone-based networked system and methods for combating coronavirus disease (COVID-19) pandemic. Future Generation Computer Systems, 115, pp.1-19.

Kurnyta, A., Reymer, P., Dziendzikowski, M., Kurdelski, M. and Leśniczak, A., 2020. Ageing Fighter–Bomber Aircraft Durability Tests and Operational Load Monitoring to Support Life Extension Program.

Le, H. and Lappas, I., 2015. Continuing airworthiness: major drivers and challenges in civil and military aviation. Aviation, 19(4), pp.165-170.

Maclean, L., Richman, A., and Hudak, M. (2018). Failure rates for aging aircraft Safety, 1(1), 1-12.

Mauthner, N.S., 2020. Research philosophies and why they matter. In How to Keep your Doctorate on Track. Edward Elgar Publishing.

MIKALAUSKAITĖ, G. and DAUKANTIENĖ, V., 2020. Investigation of the influence of bonding and thermal ageing duration on the peeling strength of knitted materials’ bonds. Materials Science, 26(2), pp.225-232.

Mofokeng, T., Mativenga, P.T. and Marnewick, A., 2020. Analysis of aircraft maintenance processes and cost. Procedia CIRP, 90, pp.467-472.

Mofokenga, T., Mativengaab, P. T., & Marnewicka, A. (2020). Analysis of aircraft maintenance processes and cost. Procedia CIRP 27th CIRP Life Cycle Engineering (LCE) Conference, 90, 467-472. Online;

Morgan, W.T., Allan, J.D., Bauguitte, S., Darbyshire, E., Flynn, M.J., Lee, J., Liu, D., Johnson, B., Haywood, J., Longo, K.M. and Artaxo, P.E., 2020. Transformation and ageing of biomass burning carbonaceous aerosol over tropical South America from aircraft in situ measurements during SAMBA.

Munch, E., 2017. A user’s guide to topological data analysis. Journal of Learning Analytics, 4(2), pp.47-61.

Pennings, G., 2020. Uterine lavage: ethics of research and clinical applications. Human Reproduction, 35(9), pp.1949-1953.

Periyarselvam U., Tamilselvan T., Thilakan S., Shanmugaraja M. (2013). Analysis on Costs for Aircraft Maintenance, 3(3), 177-82.

Pin, S., Belijar, G., Fetouhi, L., Somer, L., Van de Steen, C. and Albert, L., 2020, June. Ageing study in aircraft electromechanical chain: systems modeling for property evolution monitoring. In 2020 IEEE Electrical Insulation Conference (EIC) (pp. 79-84). IEEE.

Pin, S., Belijar, G., Fetouhi, L., Somer, L., Van de Steen, C. and Albert, L., 2020, June. Ageing study in aircraft electromechanical chain: systems modeling for property evolution monitoring. In 2020 IEEE Electrical Insulation Conference (EIC) (pp. 79-84). IEEE.

Pogačnik, B., Duhovnik, J., and Tavčar, J. (2017). Aircraft fault forecasting at maintenance service based on historic data and aircraft parameters. Maintenance Reliability, 19(4), 624-633.

Prudhomme, M., Billy, F., Alexis, J., Benoit, G., Hamon, F., Larignon, C., Odemer, G., Blanc, C. and Hénaff, G., 2018. Effect of actual and accelerated ageing on microstructure evolution and mechanical properties of a 2024-T351 aluminium alloy. International Journal of Fatigue, 107, pp.60-71.

Pyles, R. A. (2003). Aging Aircraft: USAF Workload and Material Consumption Life Cycle Patterns, Santa Monica, Calif.: RAND Corporation, MR1641-AF.

Qizi, S.S.A., 2020. INDUCTIVE AND DEDUCTIVE APPROACH IN TEACHING WRITING. Проблемы современной науки и образования, (1 (146)).

Rzevski, G., Knezevic, J., Skobelev, P., Borgest, N., and Lakhin, O. (2016). Managing aircraft lifecycle complexity. International Journal of Design & Nature and Ecodynamics, 11(2), 77-87.

Saltoğlu, R., Humaira, N. and İnalhan, G., 2016. Aircraft scheduled airframe maintenance and downtime integrated cost model. Advances in operations research, 2016.

Sekaran, U, & Bougie, R. (2016). Research Methods for Business: A Skill Building Approach. John Wiley & Sons.

Staab, F. and Balle, F., 2019. Ultrasonic torsion welding of ageing-resistant Al/CFRP joints: Properties, microstructure and joint formation. Ultrasonics, 93, pp.139-144.

Stadnicka, D., Arkhipov, D., Battaïa, O., and Ratnayake, C. R. M. (2017). Skills management in the optimization of aircraft maintenance processes. IFAC-PapersOnLine, 50(1), 6912-6917. Online;

Terry, G., Hayfield, N., Clarke, V. and Braun, V., 2017. Thematic analysis. The Sage handbook of qualitative research in psychology, pp.17-37.

Tisdall, L., Zhang, Y. and Zhang, A., 2020. Development challenges facing general aviation airports: A case study of Archerfield Airport, Queensland, Australia. Case Studies on Transport Policy, 8(4), pp.1458-1467.

Vega, D.J.G., Pamplona, D.A. and Oliveira, A.V., 2016. Assessing the influence of operations’ scale on airline industry maintenance costs. Journal of transport literature, 10(3), pp.10-14.

Vinson, G., Fanton, N., Pierre-Jean, T.I.N.E., Vitry, S. and Loustaudaudine, C., Safran Electronics, Defense SAS and Safran Landing Systems SAS, 2019. Method for monitoring the ageing of a landing gear of an aircraft. U.S. Patent 10,464,690.

Wang, B., Duan, Q.Q., Zhang, P., Zhang, Z.J., Li, X.W. and Zhang, Z.F., 2020. Investigation on the cracking resistances of different ageing treated 18Ni maraging steels. Materials Science and Engineering: A, 771, p.138553.

Wang, Y., Zhou, S., Du, H. and Zhang, W., 2019. Investigation of the thermal ageing process and mechanism of benzoxazine/bismaleimide/cyanate ester copolymer. High Performance Polymers, 31(6), pp.623-630.

Yang, Z., and Yang, G. (2012). Optimization of Aircraft Maintenance plan based on Genetic Algorithm Physics Procedia, 33, 580-586.

Yi-yong, C., Li-ping, D., and Kai, Z. (2002). Analysis of preventive maintenance program improvement for in-service aircraft. International Council of the Aeronautical Sciences, 1(1), 1-6.

MacLean, L., Richman, A. and Hudak, M., 2018. Failure rates for aging aircraft. Safety, 4(1), p.7.

Tavares, S.M.O. and De Castro, P.M.S.T., 2017. An overview of fatigue in aircraft structures. Fatigue & Fracture of Engineering Materials & Structures, 40(10), pp.1510-1529.

Frequently Asked Questions

To write the introduction chapter of a dissertation:

  1. Introduce the research topic and its importance.
  2. Provide context and background information.
  3. State the research questions or objectives.
  4. Briefly outline the structure of the dissertation.
  5. Engage the reader and set the tone for the study.