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This paper aims to evaluate the main business models used for airlines' maintenance, repair and overhaul (MRO) activities and determine the activities to which these relate.

A critical literature review is used to develop a conceptual model of MRO activities. This is evaluated through a SWOT analysis before an exploratory study of eight airlines is used to confirm the applicability of the conceptual model.

Four levels of MRO outsourcing are identified; from fully outsourced to fully in‐sourced. From the exploratory study it is shown that critical MRO activities such as line maintenance are frequently in‐sourced, while activities with low demand at an airline level such as engine maintenance are often outsourced.

MRO represent around 10‐15 per cent of an airline's operational costs. By identifying the strength and weaknesses of different MRO models, it is possible to evaluate alternative MRO strategies.

Unlike other research in maintenance which was aimed mainly at the manufacturing sectors, this research provides insights into the maintenance practises in a service sector. In particular this research studies the different outsourcing levels existing in airlines' MRO. The knowledge gained by understanding the mechanism of outsourcing in airlines' MRO can be further extended to other industries and help in best configuring their maintenance units.

This paper aims to build a novel model and approach that assist an aircraft MRO procurement and overhaul management problems from the perspective of aircraft maintenance service provider, in order to ensure its smoothness maintenance activities implementation. The mathematical model utilizes the data related to warehouse inventory management, incoming customer service planning as well as risk forecast and control management at the decision-making stage, which facilitates to alleviate the negative impact of the uncertain maintenance demands on the MRO spare parts inventory management operations.

A stochastic model is proposed to formulate the problem to minimize the impact of uncertain maintenance demands, which provides flexible procurement and overhaul strategies. A Benders decomposition algorithm is proposed to solve large-scale problem instances given the structure of the mathematical model.

Compared with the default branch-and-bound algorithm, the computational results suggest that the proposed Benders decomposition algorithm increases convergence speed.

The results among the same group of problem instances suggest the robustness of Benders decomposition in tackling instances with different number of stochastic scenarios involved.

Extending the proposed model and algorithm to a decision support system is possible, which utilizes the databases from enterprise's service planning and management information systems.

A novel decision-making model for the integrated rotable and expendable MRO spare parts planning problem under uncertain environment is developed, which is formulated as a two-stage stochastic programming model.

This research aims to develop a new generic framework for estimating different maintenance costs (preventive, corrective and conditional based) and its distribution to original equipment manufacturer (OEM), customer and supply chain due to no fault found (NFF) events. The study extend the domain of NFF to military aircraft maintenance, repair and overhaul (MRO) by including broader range of cost drivers than are normally found in maintenance NFF literature.

The research applies the soft system methodology involving 80 field surveys and five in depth semi-structured interviews with practicing experts having background in military aircraft NFF MRO. For impact analysis, authors have used an agent-based model to represent and prioritize the critical NFF cost drivers during aircraft MRO based on the cost inputs of 21 technology transfer cases.

The paper provides imperial insights about how NFF cost drivers affect the OEM, customer and supply chain. It suggests that NFF cost need to be part of the commercial MRO contract, depending on its frequency pattern in different types of maintenances.

The context of the current research is military aircrafts industry and may lack generalizability to commercial aircrafts. Therefore, researchers are encouraged to test the proposed propositions further.

The developed framework will provide invaluable help in key financial decision-making during signing of MRO contract in technology transfer cases.

This paper proposed a new prediction model for NFF cost estimation across its shareholders and current status of NFF in military aircraft NFF MRO in India.

The primary objective of this study is to propose a robust multiobjective solution search approach for a mean-variance multiple correlated quality characteristics optimisation problem, so-called “multiple response optimisation (MRO) problem”. The solution approach needs to consider response surface (RS) model parameter uncertainties, response uncertainties, process setting sensitivity and response correlation strength to derive the robust solutions iteratively.

This study adopts a new multiobjective solution search approach to determine robust solutions for a typical mean-variance MRO formulation. A fine-tuned, non-dominated sorting genetic algorithm-II (NSGA-II) is used to derive efficient multiobjective solutions for varied mean-variance MRO problems. The iterative search considers RS model uncertainties, process setting uncertainties and response correlation structure to derive efficient fronts. The final solutions are ranked based on two different multi-criteria decision-making (MCDM) techniques.

Five different mean-variance MRO cases are selected from the literature to verify the efficacy of the proposed solution approach. Results derived from the proposed solution approach are compared and contrasted with the best solution(s) derived from other approaches suggested in the literature. Comparative results indicate significant superiorities of the top-ranked predicted robust solutions in nondominated frequency, closeness-to-target and response variabilities.

The solution approach depends on RS modelling and considers continuous search space.

In this study, promising robust solutions are expected to be more suitable for implementation than point estimate-based MOO solutions for a real-life MRO problem.

No evidence of earlier research demonstrates the superiority of a MOO-based iterative solution search approach for mean-variance MRO problems by simultaneously considering model uncertainties, response correlation and process setting sensitivity.

The purpose of this paper is to address three key objectives. The first is the proposal of an enhanced multiobjective optimisation (MOO) solution approach for the mean and mean-variance optimisation of multiple “quality characteristics” (or “responses”), considering predictive uncertainties. The second objective is comparing the solution qualities of the proposed approach with those of existing approaches. The third objective is the proposal of a modified non-dominated sorting genetic algorithm-II (NSGA-II), which improves the solution quality for multiple response optimisation (MRO) problems.

The proposed solution approach integrates empirical response surface (RS) models, a simultaneous prediction interval-based MOO iterative search, and the multi-criteria decision-making (MCDM) technique to select the best implementable efficient solutions.

Implementation of the proposed approach in varied MRO problems demonstrates a significant improvement in the solution quality in worst-case scenarios. Moreover, the results indicate that the solution quality of the modified NSGA-II largely outperforms those of two existing MOO solution strategies.

The enhanced MOO solution approach is limited to parametric RS prediction models and continuous search spaces.

The best-ranked solutions according to the proposed approach are derived considering the model predictive uncertainties and MCDM technique. These solutions (or process setting conditions) are expected to be more reliable for satisfying customer specification compared to point estimate-based MOO solutions in real-life implementation.

No evidence exists of earlier research that has demonstrated the suitability and superiority of an MOO solution approach for both mean and mean-variance MRO problems, considering RS uncertainties. Furthermore, this work illustrates the step-by-step implementation results of the proposed approach for the six selected MRO problems.

The life span of an aircraft is usually around 30 years in the commercial aviation industry. During this time span, aircraft needs maintenance to stay in service. The cost of maintenance, repair and overhaul (MRO) activities in its pure nature is a significant portion of operations, accounting around 10 percent of all cost drivers. The purpose of this paper is to design/develop and critically assess a comprehensive model of operations at Turkish Technic – the MRO department of Turkish Airlines.

A comprehensive systems dynamics model is designed and developed to holistically represent and critically assess the different facets of MRO operations to help in analyzing various decision scenarios at Turkish Airlines.

The developed system dynamics (SD) model presented unique opportunities to test various MRO operations’ work load and aircraft fleet expansion policy alternatives. The model can also be used as a “learning laboratory” by altering various system parameters and testing different policies. The case study results suggested that MRO operations have a direct impact on the available number of airworthy aircrafts and hence, the usable fleet seat capacity; to sustain a profitable airline fleet, the airline companies should take into account the unique characteristics/needs of MRO operations for both existing and new/prospective aircrafts.

There are several SD studies in the literature focusing on the airline industry, but the MRO operations are virtually neglected in them. Hence, the proposed SD model contributed to the extant literature. The value of the developed model stems from its potential use in the critical analysis of decision scenarios as well as being leveraged as a training/learning laboratory.

Despite many Maintenance Repair and Overhaul (MRO) organisations alluding their positive business performances to the adoption Lean initiatives, there is a paucity of direct literature that validates this assertion. Thus, the purpose of this paper is to study empirically via the use of an industry-wide survey to establish and extent of Lean adoption and to verify its suitability in mitigating prevalent MRO challenges.

The empirical study contained in this paper is facilitated by an industry-wide survey to collect data from several firms across the MRO spectrum. The analysed responses from industry leaders, professionals and executives synthesised with existing literature was used in ascertaining the extent of Lean adoption within the operational framework of the industry.

The empirical study helped in validating the suitability of Lean in MRO context. However, it was also observed that the focus of its application was skewed towards its production-orientated functions more than its service-orientated functions. Nonetheless, this paper presents results of the positive influence of Lean in MRO context.

This empirical study presented in this paper was carried out within a framework of key characteristics of operation. Although this approach is sufficient in assessing the industry’s Lean status, further assessment can also be achieved within the context of relevant performance metrics which was not included in this paper.

By exploring the industry’s Lean status within the context of operational characteristics of operation, this study provides MRO practitioners with more awareness into some of the critical factors required for successful holistic Lean realisation.

The state-of-the-art of Lean within the aviation MRO context established through this research also contributes to the wider product-centric service environment by providing a platform that facilitates strategy development which ensures Lean success within this environment.

Apart from validating the suitability of Lean in MRO contexts, by establishing the extent of Lean adoption within the context of the operational framework, this paper provides a clearer insight as to how successful Lean implementation can be achieved via a holistic implementation strategy balanced between the product-centric and service-centric aspects of the industry.

To develop a systems strategy for supply chain management in aerospace maintenance, repair and overhaul (MRO).

A standard systems development methodology has been followed to produce a process model (i.e. the AMSCR model); an information model (i.e. business rules) and a computerised information management capability (i.e. automated optimisation).

The proof of concept for this web‐based MRO supply chain system has been established through collaboration with a sample of the different types of supply chain members. The proven benefits comprise new potential to minimise the stock holding costs of the whole supply chain whilst also minimising non‐flying time of the aircraft that the supply chain supports.

The scale of change needed to successfully model and automate the supply chain is vast. This research is a limited‐scale experiment intended to show the power of process analysis and automation, coupled with strategic use of management science techniques, to derive tangible business benefit.

This type of system is now vital in an industry that has continuously decreasing profit margins; which in turn means pressure to reduce servicing times and increase the mean time between them.

Original work has been conducted at several levels: process, information and automation. The proof‐of‐concept system has been applied to an aircraft MRO supply chain. This is an area of research that has been neglected, and as a result is not well served by current systems solutions.

The institutional logic in developing countries is changing from aid toward trade, having implications for institutionally embedded supply chains (SCs) and their members. The purpose of this study is to investigate the transition from aid toward trade through a theoretical lens of institutional logics and the implications of changing logics for SC members and designs.

This is a large-scale qualitative study of the SCs of maintenance and repair operations (MRO) of water points. Empirical data were collected via 53 semi-structured interviews, observations, including photographs, and field notes from several echelons of MRO SCs in ten different Ethiopian districts.

In spite of the same underlying tenet of a unidirectional trajectory toward a business logic, the study shows that the co-existence or constellation of different institutional logics resulted in diverse practices that impacted SC design.

The research was carried out in the MRO SC at a time of changing institutional logics, thereby being able to study their transition or constellation of logics.

The research has implications for policymakers and development practitioners: when designing and implementing rural water supply programs, the presence of co-existing logics and the lack of uniform SC designs should not be viewed as a hindrance. In fact, the study showed how constellations of logics can provide ways through which water points continue functioning and providing clean drinking water to the communities.

Few studies so far have focused on institutional logics and their implications for SC design.

This paper examines the optimisation of purchasing for maintenance, repair and operating supplies (MRO) through purchase process re‐engineering. In particular, the use and development of the Internet as a channel for procurement of MRO items was examined from a transaction cost perspective. The focus of this paper is on the impact of Web/Internet based electronic commerce on the structure of MRO supply chains. The paper provides a discussion of the theoretical basis for analysis of the impact of e‐commerce on supply chain structure, and presents existing literature in the area. The empirical research involved a series of semi‐structured interviews with UK, European and US based manufacturers, retailers, government bodies, and service organisations. Respondents ranged from experienced users of e‐procurement to organisations just starting out on their pilot investigations of the contribution of Internet trading to their purchasing efficiency. The impact on supply chain configuration of greater information transparency may be posited to be one which will lead to increased outsourcing, improved procurement processes and more strategic management of MRO purchases.